Will cultured meat soon be on our plates?

Will cultured meat soon be on our plates?

OVERVIEW

  • To preserve the planet’s environment and produce enough food to meet growing global demand, experts believe that in the future there will be a need to reduce livestock farming and conventional meat consumption.
  • Cultured meat is presented as a sustainable alternative to farmed meat for those who want to protect the environment but do not want to become vegetarians.
  • For cultured meat to be consumed on a large scale, production techniques and social acceptability will have to make significant progress.

Today there are 7.3 billion human beings on our planet, and it is expected that there will be 9 billion by 2050. The Food and Agriculture Organization (FAO) estimates that in 2050, 70% more food will be required to meet the demand of the growing population. This poses a great challenge because of limited resources and arable land. Meat production (especially beef and pork) is the most resource-intensive, and experts believe it would not be responsible, or even possible, to continue to produce more and more of these foods. Even though meat consumption is declining in developed countries, it is increasing globally because consumers in developing countries are getting richer and meat is seen by the new middle class in these countries as a desirable luxury food.

Among the solutions proposed to get out of this impasse is cultured meat (or lab-grown meat), which is presented as a sustainable alternative to farmed meat for those who want to protect the environment, but who do not wish to become vegetarians. It should be noted that some experts consider that cultured meat poses certain problems and that it would not be a viable alternative to conventional meat (see here and here). We will come back to this a little later in the text.

How is meat grown?
To grow meat, you must first obtain a muscle sample from a live adult animal (by biopsy, under anesthesia) and isolate a subpopulation of cells called “stem” or “satellite” cells. These stem cells participate in muscle regeneration and have the ability to differentiate into muscle cells themselves. The muscle stem cells are then cultured in bioreactors in the presence of a nutrient medium containing growth factors that induce rapid proliferation. The cells are then transformed into muscle cells that form structures called “myotubes” no larger than 0.3 mm in length and mechanically assembled into muscle tissue and ultimately into ground meat or artificial “steak”.

Problematic use of fetal calf serum and growth promoters
The best culture medium for growing cells contains fetal calf serum, obtained from fetal blood after slaughtering a pregnant cow. The procedure usually used (cardiac puncture of the still alive calf fetus) is considered cruel and inhumane by many. This is a problem since large numbers of calves would have to be produced to meet the demand for large-scale meat cultivation, and this use is unacceptable to vegetarians and those who follow a vegan diet or lifestyle. Fortunately, it is now possible, on a laboratory scale, to grow muscle cells without the use of fetal calf serum. However, the serum-free culture will need to be adopted on an industrial scale. To replace fetal calf serum, the industry will need to use growth factors and hormones that will need to be produced on an industrial scale. The use of growth promoters is prohibited in the European Union for conventional meat production; however, you cannot grow meat without using these growth factors and hormones. Overexposure to certain growth promoters can have harmful effects on human health, but this is a subject of debate and several countries approve the supervised use of stimulators in animal production.

From cell to steak
Real muscle (meat) is made up of muscle fibres organized into bundles, blood vessels, nerves, connective tissues, and adipocytes (fat cells). Simply producing animal muscle cells is therefore not enough to recreate meat. This is why in 2013 the first dish prepared from cultivated meat was a simple burger-type patty. Industries that develop cultured meat must now attempt to recreate a 3D structure that will resemble real meat as much as possible, a task that is proving difficult. It’s about recreating the taste experience associated with eating a steak, chicken thigh or shrimp.

Researchers have recently made progress and successfully created small samples of cultured meat that mimic real meat. Using a new approach, a Japanese research group succeeded in growing beef muscle cells in long filaments aligned in a single direction, a structure that closely resembles muscle fibres. When these cultured cells were stimulated by an electric current, the filaments contracted, similar to muscle fibres. Researchers at the University of Tokyo have so far managed to produce pieces of cultured meat weighing a few grams at most. The next challenge will be to successfully produce larger pieces of cultured meat, up to 100 g, and introduce other tissues (blood vessels, fat cells) to mimic meat more convincingly. It should be noted that the culture medium used in this study contained fetal calf serum, an ingredient that cannot be used industrially for ethical and economic reasons, as mentioned above.

Cultured chicken meat
Singapore’s food regulatory agency approved the sale of meat grown by the US company Eat Just in 2020. It was the first time that the sale of cultured meat had been permitted by a state. Eat Just grows chicken meat using a process that does not require antibiotics. This cultured meat is safe because it contains very low levels of bacteria, much less than conventional chicken meat. Cultured chicken meat contains a little more protein, has a more varied amino acid composition, and contains more monounsaturated fat than conventional meat. The muscle cells are grown in 1200-litre bioreactors and then combined with plant ingredients to make chicken nuggets. The Singapore-approved process uses fetal calf serum, but Eat Just plans to use a serum-free culture medium in their future productions.

Estimation of the environmental cost of cultured meat
Cultivated meat production offers many environmental advantages compared to conventional meat, according to a study published in 2011. It would reduce greenhouse gas (GHG) emissions by 78 to 96%, use 7 to 45% less energy and 82 to 96% less water, depending on the type of product. In contrast, a more recent and rigorous study suggests that in the long term, the impact of cultured meat on the environment may be greater than that associated with livestock farming. Cultivated meat production will certainly reduce global warming in the short term since less GHGs will be emitted compared to cattle farming. In the very long term however (i.e., several hundred years), models predict that this would not necessarily be the case, because the main GHG generated by livestock, methane (CH4), does not accumulate in the atmosphere, unlike CO2 which is practically the only GHG generated by cultivated meat. Another study based on data from 15 companies involved in the production of cultured meat concludes that it is less harmful to the environment than the production of beef, but that it has a greater impact on the environment than the production of chicken, pork and plant-based “meat”. In order for the environmental score of cultivated meat to be better than that of conventional products, the industry would have to use only sustainable energy.

Cost of cultured meat
The first cultivated beef burger was produced in 2013 by a Dutch laboratory at an estimated cost of US $416,000. In 2015, the cost of production (on an industrial scale) was reduced to around $12, and it is expected that the price could be the same as conventional meat within ten years. The cultured chicken nuggets produced by Just Eat each cost $63 to produce in 2019, so industries still have some way to go for cultured meat to become affordable enough for consumers to consume on a regular basis.

Cultured meat: an alternative for Canadians?
According to a 2018 Dalhousie University survey of 1,027 Canadians, 32.2% of respondents planned to reduce their meat consumption in the next 6 months. However, cultured meat is not very popular with Canadians as only 18.3% of those consulted said that this new type of “meat” represented an alternative to real meat for them. There is hope, however, as younger consumers (40 and under) seem more likely (34%) to view cultured meat as an alternative.

Will cultured meat one day replace conventional meat on our plates? Although there is still progress to be made before this is possible, both in terms of production and social acceptability, we can hope that the important efforts made will lead to results within a decade. Ideally, for our health and that of the planet, we should reduce our consumption of meat (of all kinds) and eat mainly plants, as is the case with the Mediterranean diet and other traditional diets.

Environmental impacts associated with food production

Environmental impacts associated with food production

OVERVIEW

  • Food production is responsible for about 25% of the greenhouse gases emitted annually, with half of these GHGs coming from animal farming, mainly in the form of methane.
  • The agricultural sector is also an important source of fine particles responsible for air pollution, with the majority of these pollutants coming from ammonia generated by livestock farming.
  • Overall, a reduction in the consumption of animal products, particularly those from cattle farming, is therefore absolutely essential to limit global warming and improve air quality.

The latest report from the Intergovernmental Panel on Climate Change (IPCC) confirms that, if nothing is done, the constant build-up of greenhouse gases (GHG) in the atmosphere will cause temperatures to increase by more than 1.5ºC above pre-industrial levels over the next century, namely the target set by the Paris Agreement to minimize the negative effects of global warming. There is therefore an urgent need to drastically reduce the emission of these gases if we want to prevent the consequences of this warming, already visible today, from becoming out of control and causing an increase in the incidence of extreme climatic events (droughts, heat waves, hurricanes, forest fires), disrupting life on Earth (extinction of species, fall in agricultural yields, increase in infectious diseases, armed conflicts) and increasing the incidence of several diseases linked to excessive heat.

Carbon dioxide and other greenhouse gases
The main greenhouse gas is carbon dioxide (CO2), which now has a concentration of 417 ppm, about twice as much as in pre-industrial times. However, it should be noted that other gases, even if they are present in smaller quantities, also contribute to global warming. These gases, such as methane or certain molecules used for industrial purposes, capture heat in a much greater way than CO2 and therefore have a higher global warming potential (GWP) than CO2. For example, a tonne of methane has a GWP 28 times greater than a tonne of CO2 over a 100-year period, while the GWP of some industrial gases such as sulfur hexafluoride can reach almost 25,000 times that of CO2 (Table 1). In other words, even if many of these gases are present in minute quantities, on the order of a few parts per billion (10-9) or even per trillion (10–12), their emission is several times that of CO2 and therefore significantly contributes to warming.

Table 1. Global warming potential of various greenhouse gases.1 Values are for the year 2018, except for CO2 which is for 2020. Derived from the United States Environmental Protection Agency (EPA).2 Calculated for a 100-year period. From Greenhouse Gas Protocol. *ppm (part per million or 10-6); **ppb (part per billion or 10-9); ***ppt (part per trillion or 10–12).

To calculate this contribution to global greenhouse gas emissions, the method generally used is to convert these emissions into CO2 equivalents (CO2eq) by multiplying their quantity in the atmosphere by their respective GWP. For example, 1 kg of SF6 is equivalent to 23,500 kg (23.5 tonnes) of CO2 (1 kg × 23,500 = 23,500 CO2eq), while it takes 1000 kg of methane to reach an equivalent amount of CO2 (1000 kg × 28 = 28,000 CO2eq). When this method is applied to all gases, it is estimated that 75% of greenhouse gas emissions are in the form of CO2, the remainder coming from methane (17%), nitrous oxide (6%), and various fluorinated gases (2%) (Figure 1).

Figure 1. Distribution of greenhouse gas emissions. Adapted from Ritchie and Roser (2020).


Emissions sources
The use of fossil fuels to support human activities (transport, electricity production, heating, various industrial processes) is the main source of greenhouse gases, accounting for around three quarters of total emissions (Figure 2). This enormous “carbon footprint” implies that the fight against global warming necessarily requires a transition to “cleaner” sources of energy, in particular with regard to transport and electricity production. This is especially true in a country like Canada, where we emit an average of 20 tonnes of CO2eq per person per year, which ranks us, along with the United States and Australia, among the worst producers of GHGs in the world (Quebec, for its part, does better, with about 10 tonnes of CO2eq per person per year).


Figure 2. Contribution of the food sector to the annual production of greenhouse gases. Adapted from Ritchie and Roser (2020).

Another industry that contributes significantly to greenhouse gas emissions, but that we hear much less about, is food production. It is estimated that around 25% of all these gases come from the production and distribution of food, a proportion that rises to 33% when food waste is taken into account. The food sector involved in animal protein production alone is responsible for half of these food-related GHG emissions, mainly due to methane produced by livestock and aquaculture (31%) (see box). Livestock farming also requires large spaces, created in some cases by massive deforestation (in the Amazon, for example), which eliminates huge areas of plants that can sequester COs. Livestock farming also requires large quantities of forage plants and therefore the use of nitrogen fertilizers to accelerate the growth of these plants. The CO2 and nitrous oxide released into the atmosphere during the production of these fertilizers therefore contribute to the GHG generated by livestock.

Where does methane come from?
Methane (CH4) is the end product of the decomposition of organic matter. Methanogenesis is made possible by certain anaerobic microorganisms from the archaea domain (methanogens) which reduce carbon, present in the form of CO2 or certain simple organic acids (acetate, for example), to methane, according to the following reactions:

CO+ 4 H2 → CH4 + 2 H2O

CH3COOH → CH4 + CO2

The methane generated by livestock comes mainly from the fermentation of carbonaceous products inside the digestive system of ruminants. In these animals, the digestion of plant matter generates volatile fatty acids (acetate, propionate, butyrate), which are absorbed by the animal and used as a source of energy, and lead in parallel to the production of methane, about 500 L per day per animal, most of it being released through the mouth of the animal. Globally, livestock is estimated to emit about 3.1 Gt of CO2-eq as methane, which represents almost half of all anthropogenic methane emissions.

Aquaculture is another rapidly expanding form of farming, now accounting for over 60% of the global supply of fish and seafood for human consumption. Although GHG emissions from this sector are still much lower than those associated with livestock, recent measurements nonetheless indicate a sharp increase in its global warming potential, mainly due to an increase in methane production. In these systems, the sediments accumulate food residues used for the growth of fish and seafood as well as the droppings generated by these animals. The transformation of this organic material leads to the production of methane, which can then be diffused into the atmosphere.

Finally, it should be noted that the majority of aquaculture systems are located in Asia, where they are often established in regions previously occupied by mangroves, ecosystems located along the coasts and deltas of tropical regions. The destruction of these mangroves (very often for shrimp farming) is very harmful to global warming, because mangrove forests collectively store around 4 billion tonnes of CO2 and their elimination therefore has a concrete impact on the climate.

A good way to visualize the impact of livestock farming on GHG production is to compare the emissions associated with different foods of animal and plant origin based on the amount of protein in these foods (Figure 3). These comparisons clearly show that products derived from livestock products, beef in particular, represent a much greater source of GHGs than plants. The production of 100 g of beef protein, for example, generates on average 100 times more GHGs than the same amount of protein from nuts or legumes. This is true even for beef produced in the traditional way, i.e., from animals that feed exclusively on grass: these animals grow more slowly and therefore emit methane for a longer period, which cancels out the benefits that could be associated with the sequestration of CO2 by the grass that they eat.

Figure 3. Comparison of GHG levels generated during the production of different protein sources. Based on Poore and Nemecek (2018), as modified by Eikenberry (2018).

These huge differences in GHGs associated with the production of everyday food therefore clearly show that our food choices can have a significant influence on global warming. Since the majority of GHG emissions come from livestock, it is evident that a reduction in the consumption of meat, and animal products as a whole, will have the most positive impact. These benefits can be observed even with a fairly modest reduction in meat intake, as in the Mediterranean diet, or simply by replacing products from ruminants (beef and dairy products) by other sources of animal protein (poultry, pork, fish) (Figure 4). Obviously, a more drastic reduction in meat intake is even more beneficial, whether through the adoption of a flexitarian diet (high intake of plants, but little meat and animal products), vegetarian (no animal products, with the exception of eggs, dairy products and sometimes fish), and vegan (no animal products). This remains true even if the plants consumed come from abroad and sometimes travel long distances, because contrary to popular belief, transport only accounts for a small proportion (less than 10%) of the GHGs associated with a given food.

Figure 4. Potential for mitigation of GHG emissions by different types of diets. Adapted from IPCC (2019).

It is impossible to completely decarbonize food production, especially in a world where there are over 9 billion people to feed daily. On the other hand, there is no doubt that the GHG footprint of food can be significantly reduced by reducing the consumption of products derived from ruminants, such as beef and dairy products. This is extremely important, because the status quo is untenable. According to recent models, even if GHG emissions from fossil fuels ceased immediately, we would still not succeed in reaching the target of a maximum warming of 1.5ºC due to emissions produced by the current food production system.

Another aspect that is often overlooked is how fast and significant this positive impact of a reduction in cattle breeding products can be. Even though methane is a GHG almost 30 times more powerful than CO2, its life in the atmosphere is much shorter, around 10–20 years vs. several thousand years for CO2. Concretely, this means that an immediate drop in methane emissions, for example following a drastic reduction in the consumption of beef and dairy products, can have measurable effects on GHG levels in the following years and therefore represents the fastest and most efficient way to slow global warming.

Pollution from food
In addition to contributing to global GHG emissions, another environmental impact of food production is its contribution to air pollution. This negative impact of the food sector should not be overlooked, because while the influence of global warming caused by GHGs will be felt above all in the medium and longer term, atmospheric pollutants have an immediate effect on health: air pollution is currently the 7th leading cause of premature death worldwide, being directly responsible for around 4 million deaths annually (Figure 5). In some countries, such as the United States, it is estimated that agriculture and livestock are responsible for about 20% of this air pollution-related mortality.

Figure 5. Leading causes of premature mortality worldwide. Note that air pollution is the only risk factor of environmental origin, not related to lifestyle. From GBD 2016 Risk Factors Collaborators (2016).

Fine particles of 2.5 µm and less (PM2.5) are mainly responsible for these negative impacts of air pollution on health. Due to their small size, these particles easily penetrate the lungs to the pulmonary alveoli, where they pass directly to the pulmonary blood vessels and then to all arteries in the body. They then produce an inflammatory reaction and oxidative stress that damage the vascular endothelium, the thin layer of cells that covers the inner walls of the arteries and ensures their proper functioning. The arteries therefore dilate less easily and tend to contract more, which interferes with normal blood circulation. For all these reasons, it is cardiovascular diseases (coronary heart disease and stroke) that represent the main consequence of exposure to fine particles, and alone are responsible for about 80% of all deaths caused by ambient air pollution (Figure 6).

Figure 6. Distribution of premature deaths (in millions) caused by fine particles PM2.5.
Note the predominance of cardiovascular disease as a cause of death linked to air pollution. Adapted from Lelieveld et al. (2015).

Primary and secondary particles
Fine particles can be emitted directly from polluting sources (primary PM2.5) or indirectly, following the combination of several distinct particles present in the atmosphere (secondary PM2.5) (Figure 7). Much of the primary PM2.5 is in the form of carbon soot, produced by the incomplete combustion of fossil fuels (diesel and coal, especially) or biomass (forest fires, for example). Carbon soot is also associated with various organic compounds (polycyclic aromatic hydrocarbons), acids, metals, etc., which contribute to its toxicity after inhalation. These particles can be transported aloft over very long distances and, once deposited, be resuspended in the wind. In urban areas, this resuspension also takes place under the action of road traffic. This turbulence associated with automobile traffic is also responsible for the production of another class of primary PM2.5 called fugitive road dust.

Secondary PM2.5, on the other hand, are formed from precursors such as sulfur dioxide (SO2), nitrogen oxides (NOx), various volatile organic compounds containing carbon (organic carbon) as well as ammonia (NH3). The chemical reactions that govern the interaction between these different volatile substances to form the secondary fine particles are extraordinarily complex, but let us only mention that it is well established that the presence of the ammonium ion (NH4+), derived from ammonia (NH3), neutralizes the negative charge of certain gases and thus promotes their aggregation in the form of fine particles (Figure 7). Consequently, the presence of NH3 in the atmosphere often represents a limiting step in the formation of these secondary fine particles and a reduction in these emissions can therefore have concrete effects on improving air quality.


Figure 7. Schematic representation of the mechanisms of formation of fine particles PM2.5.

It is this important role of ammonia in the formation of secondary fine particles that explains the contribution of the food production sector to air pollution. Agriculture and livestock are in fact responsible for almost all anthropogenic ammonia emissions, a consequence of intensive livestock farming, the spreading of manure and slurry, and the industrial production of nitrogen fertilizers.

An American study clearly illustrates this contribution of agricultural ammonia to the negative impacts of air pollution on health. In this study, the researchers show that of the approximately 18,000 deaths caused annually by pollution derived from the agricultural sector, the vast majority (70%) of these deaths are a consequence of ammonia emissions (and therefore secondary PM2.5), while the emission of primary PM2.5, from plowing, the combustion of agricultural residues, and machinery, is responsible for the rest. Since the vast majority of ammonia emissions come from animal faeces and the use of natural (manure and slurry) or synthetic fertilizers to grow food for these animals, it is not surprising that the production of food from livestock is the main cause of deaths attributable to pollution from agricultural sources (Figure 8).

Figure 8. Distribution of deaths caused annually by PM2.5 from the agricultural sector in the United States. Note that 70% of the mortality is attributable to livestock products, mainly due to the ammonia generated by the animals as well as by the spreading of manure, slurry and synthetic fertilizers for the cultivation of fodder plants (corn, soybeans). From Domingo et al. (2021).

When we compare the impact of different foods for the same quantity of product, we immediately see that the production of red meat is particularly damaging, being responsible for at least 5 times more deaths than that of poultry, 10 times more than that of nuts and seeds, and at least 50 times more than that of other plants such as fruits and vegetables (Figure 9).

Figure 9. Comparison of PM2.5-related mortality by food types. From Domingo et al. (2021).

In short, whether in terms of reducing GHG emissions or health problems associated with atmospheric pollution, all the studies unequivocally show that a reduction in environmental damage caused by food production necessarily involves a reduction in the consumption of products of animal origin, in particular those from cattle farming. A change that is all the more profitable as the reduction in the intake of food of animal origin, combined with an increase in the consumption of plants, is beneficial for health and could prevent about 11 million premature deaths annually, a decrease of 20%.

The impact of forest fires on human health

The impact of forest fires on human health

OVERVIEW

  • Wildfires will be increasingly frequent given climate change that is leading to higher temperatures and drought in many parts of the world.
  • Smoke from forest fires produces fine and ultrafine particles that can travel up to 1,000 kilometres and affect the health of people from afar.
  • In the short term, smoke from wildfires is mainly harmful to respiratory health. Some populations are more at risk of suffering the consequences.
  • The increase in forest fires may in turn contribute to climate disruption.

 

From British Columbia to the island of Evia, wildfires are increasingly part of the global landscape. The health impacts of these blazes on global health are unequivocal. Here is an overview of a natural phenomenon exacerbated by climate change.

The recent report of the IPCC, the Intergovernmental Panel on Climate Change, highlights that forest fires are likely to be more frequent and severe given the acceleration of climate change.1 Higher temperatures favour the development of lightning, which is the main natural cause of wildfires. A climate predicted to be drier and windier will promote combustion and the spread of forest fires.2 The fire season will therefore last longer. By 2039, the frequency of fires could increase over 37.8% of the planet with a rise of just 1.2 °C in global temperature. With an increase of 3.5 °C, 61.9% of the world territory will be affected by more frequent fires by 2100.3 In the most pessimistic climate scenario where greenhouse gas emissions continue to rise, this risk will affect up to 74% of the world’s land surface by the end of the century. The United States, Canada, Mediterranean countries, China and Australia will be particularly affected.4

In Canada, it is estimated that more than 8,000 fires occur each year. On average, more than 2.1 million hectares are destroyed annually, equivalent to the area of Victoria Island.5 In all the provinces, weather conditions will be increasingly conducive to wildfires. The areas burned could thus double by 2100.6

The smoke from wildfires is made up of carbon monoxide, carbon dioxide, nitrogen oxides, and other organic compounds. These vary according to several factors, such as the type of vegetation and the temperature of the fire.7 Fires also produce fine particles (diameter ≤ 2.5 μm or PM2.5) and ultrafine particles (diameter ≤ 0.1 μm or PM0.1) that can travel up to 1,000 km.2 It is mainly these particles that are harmful to the health of populations living at a distance from fire outbreaks. Fine particles produced by wildfires may also contain more oxidative and pro-inflammatory compounds than urban air pollution caused by burning fossil fuels.8 One study suggests that fine particles from wildfires may be 10 times more harmful to human health than those produced by other sources.9

Impact on human health

Population near forest fires
Populations near fires and first responders are at risk of direct injury from burns, heat, and direct smoke inhalation. Smoke can also irritate the eyes, cause corneal abrasions, reduce visibility, and increase the risk of traffic accidents in areas near the fires.10

Respiratory health
For local or remote populations, fine and ultrafine particles enter the respiratory tract and cause inflammation to the lungs. Exposure to fine particles mainly causes respiratory symptoms, such as coughing or difficulty breathing.7

Many exposed individuals will not have any symptoms, but some are more likely to develop them. The extent of exposure to smoke and the presence of vulnerability factors may modulate the severity of the clinical presentation, as shown in Figure 1.

Figure 1. Clinical and subclinical impact of fine particles from wildfires. From Cascio (2018).11

Patients with asthma or chronic obstructive pulmonary disease may experience more exacerbations of their respiratory symptoms, use more medications to control them, and seek more health care services.121314 People aged 65 and over, those working outdoors, and those residing in disadvantaged neighbourhoods are also more vulnerable to fine particles from fires.15 Children are also more susceptible to the harmful effects of smoke. A less well-developed immune system and a higher basal respiratory rate in children could explain this vulnerability.2

Cardiovascular health
Are the fine particles produced specifically by forest fires harmful to cardiovascular health? The answer remains to be clarified. While some studies show a significant risk of cardiovascular disease associated with exposure, others do not.1416

Among these, a study analyzing 2.5 million hospitalizations in areas 200 km from wildfires in the United States suggests that the risk of cardiovascular disease may be comparable to that of urban air pollution.17

Another study conducted on the 2015 California wildfires shows an association between exposure to smoke and increased emergency room visits related to cardiovascular diseases, such as myocardial infarction, ischemic heart disease, heart failure, hypertension, and arrhythmias. Adults 65 years of age and older were particularly affected. An association between smoke density and cerebrovascular events, such as stroke, has also been noted by researchers.18

Australian studies have also shown an association between exposure to fine particles from wildfires and the risk of cardiac arrest in the community.1920

Of note, short-term exposure (less than 3 hours) to smoke produced by burning wood has the potential to increase central arterial stiffness, heart rate and decrease heart rate variability. In other words, wood smoke could have harmful hemodynamic effects on the cardiovascular system.21

In short, fine particles from fires are added to those generated by global air pollution, well known to worsen the incidence of cardiovascular disease.

Mortality
Exposure to smoke from forest fires is associated with an increased risk of mortality from non-specific and non-accidental causes.2 In Canada, from 2013 to 2018, 620 to 2,700 premature deaths were reported to have been caused by smoke from forest fires.22 Current data do not allow us to establish a clear link between exposure to fine particles from forest fire smoke and an increase in mortality from a specific cause, such as respiratory or cardiac.

However, it should be noted that short-term exposure to fine particles caused by global air pollution is associated with an increased risk of mortality.23 Even short-term exposure to fine particles could increase the risk of myocardial infarction mortality.24 In other words, smoke from wildfires could be a risk factor for cardiovascular mortality, but this has yet to be clarified.

Other effects on physical health
Some studies suggest that pregnant women exposed to fine particles from forest fires may be at greater risk of giving birth prematurely or having a low birth weight baby. However, the data remain limited and should be interpreted with caution.2

In addition, one study found a marked increase in the number of influenza cases a few months after intense forest fires in the Montana region (USA). This could suggest a certain vulnerability to respiratory infections following exposure to smoke.25 The fine particles produced by fires could alter the function of macrophages, cells of the immune system, reducing the body’s ability to effectively defend itself against respiratory tract infections.26 In this sense, some researchers are currently evaluating the impact of air pollution from forest fires on the transmission and severity of COVID-19 cases.272829

Overall, more studies are needed to better understand the medium- and long-term impact of wildfire smoke on human health.

Mental health
Wildfires can be devastating for the communities living nearby. Emergency evacuations and the loss of one’s physical and social environment are intense stressors that can have an impact on mental health, particularly in children and adolescents.30 People directly exposed to wildfires are at greater risk of major depression, post-traumatic stress disorder, and anxiety disorders.10 Access to psychological support services is therefore essential for populations strongly affected by forest fires.

Socio-economic impacts
Wildfires are also associated with greater use of medical resources. There are more medical consultations in emergency rooms, family medicine clinics and hospitalizations.31 In Canada, the annual health costs associated with fine particles from forest fires are estimated at between $410 million and $1.8 billion for short-term exposure. From $4.3 billion to $19 billion are attributable to chronic exposure.22 This adds to many societal costs, such as those associated with rebuilding infrastructure, contamination of drinking water by smoke ash, and loss of income.11

Environmental health
Although exacerbated by human pollution, wildland fires themselves contribute to climate change. Combined with the continued emission of greenhouse gases from human activities, the loss of vegetation reduces the absorption of carbon dioxide and thus contributes to the increase in the temperature of the earth. Forest fires could also contribute to the melting of permafrost and thus promote the emission of methane,2 a gas whose potential for warming the atmosphere is 25 times greater than carbon dioxide.32

What to do about forest fires?

Learn about air quality
In Canada, the Air Quality Health Index provides information about air quality across the country33 and the FireWork forecasting system helps predict the movement of smoke from forest fires.34 The Canadian government’s WeatherCAN application is also a weather forecasting tool accessible to the population.35 Local authorities are also responsible for issuing air quality warnings and health recommendations.

Reduce exposure to air pollution
Figure 2 summarizes the main measures to be taken to reduce the impact of wildfire smoke on health. In order to limit exposure to fine particles following a forest fire, recommendations may vary depending on the location. The net effectiveness of these interventions still needs to be clarified, as they are based on a limited number of small-scale studies.36 It is advisable to avoid outdoor activities, including physical exercise, when the atmospheric level of fine particles is too high.15

In order to reduce the infiltration of outdoor air into buildings, it is useful to close doors and windows if the heat is not too overwhelming inside. High levels of fine particles in the atmosphere can be associated with intense heat waves. If the temperature inside is too high, the heat can be harmful to health, especially in the elderly or those with chronic diseases. Setting the heating, ventilation and air conditioning systems to recirculation mode and limiting the use of the kitchen hood are also recommended measures to reduce air intake.37

Air purifiers with HEPA (high efficient particulate air) filters effectively reduce the level of fine particles and are recommended by the Government of Canada. However, these are not able to remove some polluting gases from the air. In addition, air purifiers can be expensive and therefore less accessible to everyone.2

As for wearing a mask, the surgical type is not recommended, since it does not protect against fine particles. N95 masks offer better protection, but they require an individual fit test, can give a false sense of security, and are not suitable for children. The use of these masks is recommended for workers exposed to smoke from fires.38 Finally, the creation of community smoke-free spaces is also a measure that can be implemented by local authorities when the level of air pollution increases.39

Figure 2. Key actions individuals can take to reduce exposure to wildfire smoke and its health risks. From Rongbin et al. (2020)2


Preventing climate change
Globally, the main goal to reduce forest fires and their health consequences would be to limit the global temperature increase to 1.5 °C instead of the 2° C targeted by the Paris Agreement. This limited increase would prevent more than 50% of the predicted forest fires if the global temperature rises by 2° C.4

The IPCC report highlights that even the 2° C target will be exceeded without massive and imminent interventions. Concerted government actions are therefore more than necessary to substantially reduce anthropogenic greenhouse gas emissions.

Conclusion In sum, the air pollution emitted by forest fires is associated with an increase in morbidity and mortality. Some health effects remain to be elucidated. These increasingly frequent fires reflect the impact of climate change on human health. In the short and long term, interventions and prevention measures to protect the population will be necessary in order to mitigate the social, economic and environmental consequences of these climatic upheavals.  

 

References

(1) IPCC, 2021: Summary for Policymakers. In: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Masson-Delmotte, V. et al. (eds.)]. Cambridge University Press.

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Effects of cold on cardiovascular health

Effects of cold on cardiovascular health

OVERVIEW

  • Exposure to cold causes a contraction of blood vessels as well as an increase in blood pressure, heart rate, and the work of the heart muscle.
  • The combination of cold and exercise further increases stress on the cardiovascular system.
  • Cold temperatures are associated with increased cardiac symptoms (angina, arrhythmias) and an increased incidence of myocardial infarction and sudden cardiac death.
  • Patients with coronary artery disease should limit exposure to cold and dress warmly and cover their face when exercising.

Can the sometimes biting cold of our winters affect our overall health and our cardiovascular health in particular? For an exhaustive review of the literature on the effects of cold on health in general, see the summary report (in French only) recently published by the Institut national de santé publique du Québec (INSPQ). In this article, we will focus on the main effects of cold on the cardiovascular system and more specifically on the health of people with cardiovascular disease.

Brief and prolonged exposure to cold both affect the cardiovascular system, and exercise in cold weather further increases stress on the heart and arteries. Numerous epidemiological studies have shown that cardiovascular disease and mortality increase when the ambient temperature is cold and during cold spells. The winter season is associated with a greater number of cardiac symptoms (angina, arrhythmias) and cardiovascular events such as hypertensive crisis, deep venous thrombosis, pulmonary embolism, aortic ruptures and dissections, stroke, intracerebral hemorrhage, heart failure, atrial fibrillation, ventricular arrhythmia, angina pectoris, acute myocardial infarction, and sudden cardiac death.

Mortality from cold
Globally, more temperature-related deaths were caused by cold (7.29%) than heat (0.42%). For Canada, 4.46% of deaths were attributable to cold (2.54% for Montreal), and 0.54% to heat (0.68% for Montreal).

Intuition may lead us to believe that it is during periods of extreme cold that more adverse health effects occur, but the reality is quite different. According to a study that analyzed 74,225,200 deaths that occurred between 1985 and 2012 in 13 large countries on 5 continents, extreme temperatures (cold or hot) accounted for only 0.86% of all deaths, while the majority of cold-related deaths occurred at moderately cold temperatures (6.66%).

Acute effects of cold on the cardiovascular system of healthy people

Blood pressure. The drop in skin temperature upon exposure to cold is detected by skin thermoreceptors that stimulate the sympathetic nervous system and induce a vasoconstriction reflex (decrease in the diameter of the blood vessels). This peripheral vasoconstriction prevents heat loss from the surface of the body and has the effect of increasing systolic (5–30 mmHg) and diastolic (5–15 mmHg) blood pressure.

Heart rate. It is not greatly affected by exposure of the body to cold air, but it increases rapidly when, for example, the hand is dipped in ice water (“cold test” used to make certain diagnoses, such as Raynaud’s disease) or when very cold air is inhaled. Cold air usually causes a slight increase in heart rate in the range of 5 to 10 beats per minute.

Risk of atheromatous plaque rupture?
Post-mortem studies have shown that rupture of atheroma plaques (deposits of lipids on the lining of the arteries) is the immediate cause of over 75% of acute myocardial infarctions. Could cold stress promote the rupture of atheromatous plaques? In a laboratory study, mice exposed to cold in a cold room (4°C) for 8 weeks saw their blood LDL cholesterol level and the number of plaques increase compared to mice in the control group (room at 30°C). Furthermore, it is known that exposure to cold induces aggregation of platelets in vitro and increases coagulation factors in vivo in patients during colder days (< 20°C) compared to warmer days (> 20°C). Combined, these cold effects could help promote plaque rupture, but to date no study has been able to demonstrate this.

Risk of cardiac arrhythmias
Arrhythmias are a common cause of sudden cardiac death. Even in healthy volunteers, the simple act of dipping a hand in cold water while holding the breath can cause cardiac arrhythmias (nodal and supraventricular tachycardias). Could cold promote sudden death in people at risk for or with heart disease? Since arrhythmias cannot be detected post-mortem, it is very difficult to prove such a hypothesis. If it turns out that exposure to cold air can promote arrhythmias, people with coronary artery disease may be vulnerable to the cold since the arrhythmia would amplify the oxygenated blood deficit that reaches the heart muscle.

Effects of cold combined with exercise
Both cold and exercise individually increase the heart’s demand for oxygen, and the combination of the two stresses has an additive effect on this demand (see these two review articles, here and here). Exercising in the cold therefore results in an increase in systolic and diastolic blood pressure as well as in the “double product” (heart rate x blood pressure), a marker of cardiac work. The increased demand for oxygen by the heart muscle caused by cold weather and exercise increases blood flow to the coronary arteries that supply the heart. The rate of coronary blood flow increases in response to cold and exercise combined compared to exercise alone, but this increase is mitigated, especially in older people. Therefore, it appears that cold causes a relative lag between the oxygen demand from the myocardium and the oxygenated blood supply during exercise.

In a study carried out by our research team, we exposed 24 coronary patients with stable angina to various experimental conditions in a cold room at – 8°C, specifically a stress test with electrocardiogram (ECG) in cold without antianginal medication and an ECG at + 20°C. We then repeated these two ECGs after taking one drug (propranolol) that slows the heart rate, and then another drug (diltiazem) that causes dilation of the coronary arteries. The results showed that the cold caused mild to moderate ischemia (lack of blood supply) to the myocardium in only 1/3 of the patients. When ECG was done with medication, this effect was completely reversed. The two drugs have been shown to be equally effective in reversing this ischemia. The conclusion: cold had only a modest effect in 1/3 of patients and antianginal drugs are as effective in cold (- 8°C) as at + 20°C.

In another study in the same type of patients, we compared the effects of an ECG at – 20°C with an ECG at + 20°C. The results showed that at this very cold temperature, all patients presented with angina and earlier ischemia.

Hypertension
The prevalence of hypertension is higher in cold regions or during winter. Cold winters increase the severity of hypertension and the risk of cardiovascular events such as myocardial infarction and stroke in people with hypertension.

Heart failure
The heart of patients with heart failure is not able to pump enough blood to maintain the blood flow necessary to meet the body’s needs. Only a few studies have looked at the effects of cold on heart failure. Patients with heart failure do not have much leeway when the heart’s workload increases in cold weather or when they need to exert sustained physical effort. Cold combined with exercise further decreases the performance of people with heart failure. For example, in a study we conducted at the Montreal Heart Institute, cold reduced exercise time by 21% in people with heart failure. In the same study, the use of beta-blocker class antihypertensive drugs (metoprolol or carvedilol) significantly increased exercise time and reduced the impact of cold exposure on the functional capacity of patients. Another of our studies indicates that treatment with an antihypertensive drug from the class of angiotensin converting enzyme inhibitors, lisinopril, also mitigates the impact of cold on the ability to exercise in patients with heart failure.

Cold, exercise and coronary heart disease
It is rather unlikely that the cold alone could cause an increase in the work of the heart muscle large enough to cause a heart attack. Cold stress increases the work of the heart muscle and therefore the blood supply to the heart in healthy people, but in coronary patients there is usually a reduction in blood flow to the coronary arteries. The combination of cold and exercise puts coronary patients at risk of cardiac ischemia (lack of oxygen to the heart) much earlier in their workout than in warm or temperate weather. For this reason, people with coronary artery disease should limit exposure to cold and wear clothes that keep them warm and cover their face (significant heat loss in this part of the body) when working out outdoors in cold weather. In addition, the exercise tolerance of people with coronary heart disease will be reduced in cold weather. It is strongly recommended that coronary heart patients do indoor warm-up exercises before going out to exercise outdoors in cold weather.

Do houseplants have beneficial effects on health?

Do houseplants have beneficial effects on health?

OVERVIEW

Having and caring for houseplants can:

  • Reduce psychological and physiological stress.
  • Improve recovery after surgery.
  • Increase attention and concentration.
  • Increase creativity and productivity.

In our modern societies, where everything seems to go faster and faster, many feel the harmful effects of stress and anxiety; however, this appears to have increased since the start of the COVID-19 pandemic. During spring and summer 2020, many Quebecers took advantage of the beautiful weather to recharge their batteries in nature, either by visiting a park, camping, walking in the forest, or renting a cottage in the countryside. As winter approaches, contact with greenery becomes scarce and travel to regions with warmer climates is risky and strongly discouraged by Public Health. Apart from hiking in our beautiful coniferous forests, one of the only possible contacts with greenery during this long winter will be the green plants we take care of in our homes. Houseplants decorate and bring a natural touch to our homes, but do they have proven beneficial effects on our physical and mental health.

Stress reduction
A systematic review in 2019 identified some 50 studies on the psychological benefits of houseplants, most of these studies being of average quality. The most noticeable positive effects of houseplants on participants are an increase in positive emotions and a decrease in negative emotions, followed by a reduction in physical discomfort.

In a randomized, controlled crossover study of young adults, participants saw their mood improve more after transplanting an indoor plant than after performing a task on the computer. In addition, participants’ diastolic blood pressure and sympathetic nervous system activity (physiological response to stress) were significantly lower after transplanting a plant than after performing a computer task. These results indicate that interaction with houseplants can reduce psychological and physiological stress compared to mental tasks.

Plants in the office
In 2020, a Japanese team carried out a study on the effects of plants in the workplace on the level of psychological and physiological stress of workers. In the first phase of the study (1 week), workers worked at their desks without a plant, while in the intervention phase (4 weeks), participants could see and care for an indoor plant that they were able to choose from six different types (bonsai, Tillandsia, echeveria, cactus, leafy plant, kokedama). Participants were instructed to take a three-minute break when feeling tired and to take their pulse before and after the break. During these 3-minute breaks, workers had to look at their desks (with or without an indoor plant). Researchers measured psychological stress with the State-Trait Anxiety Inventory (STAI). The participants’ involvement was therefore both passive (looking at the plant) and active (watering and maintaining the plant).

The psychological stress assessed by STAI was significantly, albeit moderately, lower during the intervention in the presence of an indoor plant than during the period without the plant. The heart rate of the majority of patients (89%) was not significantly different before and after the procedure, while it decreased in 4.8% of participants and increased in 6.3% of patients. It must be concluded that the intervention had no effect on heart rate, which is an indicator of physiological stress, although it slightly reduced psychological stress.

A study of 444 employees in India and the United States indicates that office environments that include natural elements such as indoor plants and exposure to natural light positively influence job satisfaction and engagement. These natural elements seem to act as “buffers” against the effects of stress and anxiety generated by work.

Recovery after surgery
It appears that houseplants help patients recover after surgery, according to a study in a hospital in Korea. Eighty women recovering from thyroidectomy were randomly assigned to a room without plants or to a room with indoor plants (foliage and flowering). Data collected for each patient included length of hospital stay, use of analgesics to control pain, vital signs, intensity of perceived pain, anxiety and fatigue, STAI index (psychological stress), and other questionnaires. Patients who were hospitalized in rooms with indoor plants and flowers had shorter hospital stays, took fewer painkillers, experienced less pain, anxiety, and fatigue, and they had more positive emotions and greater satisfaction with their room than patients who recovered from their operation in a room without plants. The same researchers performed a similar study in patients recovering after an appendectomy. Again, patients who had plants and flowers in their rooms recovered better from their surgery than those who did not have plants in their rooms.

Improved attention and concentration
Twenty-three elementary school students (ages 11–13) participated in a study where they were put in a room with either an artificial plant, a real plant, a photograph of a plant, or no plant at all. The participants wore a wireless electroencephalography device during the three minutes of exposure to the different stimuli. Children who were put in the presence of a real plant were more attentive and better able to concentrate than those in the other groups. In addition, the presence of a real plant was associated with a better mood in general.

Productivity
A cross-sectional study of 385 office workers in Norway found a significant, albeit very modest, association between the number of plants in their office and the number of sick days and productivity. Workers who had more plants in their office took slightly fewer sick days and were a bit more productive on the job. In another study, American students were asked to perform computer tasks, with or without houseplants, in windowless rooms. In the presence of plants, participants were more productive (12% faster in performing tasks) and less stressed since their blood pressure was lower than in the absence of houseplants.

What about air quality?
Do plants purify the air in our homes? This is an interesting question since we spend a lot of time in increasingly airtight homes, and materials and our activity (e.g. cooking) emit pollutants such as volatile organic compounds (VOCs), oxidizing compounds (e.g. ozone), and fine particles. A NASA study showed that plants and associated microorganisms in the soil could reduce the level of pollutants in a small, sealed experimental chamber. Are these favourable results obtained in a laboratory also observable in our homes, schools and offices? Some studies (this one for example) conclude that plants decrease the concentrations of CO2, VOCs and fine particles (PM10). However, these results have been called into question by researchers (see this study) who question the methodology used in previous studies and who believe that plants are ineffective in improving the indoor air quality of our buildings. According to these researchers, it would be better to focus research efforts on other air-cleaning technologies as well as on the beneficial effects of plants on human health.

Conclusion
Indoor plants can provide health benefits by reducing psychological and physiological stress. Owning and maintaining plants can improve mood and increase attention and concentration. New, more powerful and better controlled studies will be needed to better identify and understand the effects of plants on human health.

Beyond Burger, Impossible Burger and other products that mimic meat: are they good for health and the environment?

Beyond Burger, Impossible Burger and other products that mimic meat: are they good for health and the environment?

Red meat: An issue for human health and the health of the planet.
Consumption of red meat and processed meat is associated with an increase in all-cause mortality and mortality from cardiovascular diseases, diabetes, respiratory diseases, liver and kidney diseases, and certain cancers. On the contrary, consumption of white meat and fish has been associated with a decreased risk of premature death. Another troubling aspect with the production of red meat is that it is harmful to the global environment.

In traditional European agricultural societies, meat was consumed once or less than once a week, and annual meat consumption rarely exceeded 5 to 10 kg per person. In some rich countries (U.S.A., Australia, New Zealand), meat consumption now stands at 110–120 kg per person per year, > 10 times more than in traditional agricultural societies. Livestock farming occupies more than 30% of the world’s land area, and more than 33% of arable land is used to produce livestock feed. World consumption of red meat is rising sharply, especially in developing countries. This has adverse consequences for the environment and represents an unsustainable situation according to several experts.

The main harmful effects to our planet caused by meat production (Potter, BMJ 2017)

  • Depletion of aquifers (producing 1 kg of meat requires more than 110,000 L of water).
  • Groundwater pollution.
  • Decrease of biodiversity.
  • Destruction of rainforest for livestock and the production of greenhouse gases by livestock. Both combined contribute more to climate change than fossil fuels used for transport.
  • Production of 37% of methane (CH4) from human activity (with 23 times the global warming
    potential of CO2).
  • Production of 65% of nitrous oxide (N2O) from human activity (almost 300 times the global
    warming potential of CO2).
  • Production of 64% of ammonia (NH3) from human activity, which contributes significantly to
    acid rain and acidification of the ecosystem.

Other potential negative effects associated with red meat include accelerated sexual development, caused either by the consumption of meat and fat, or by the intake of growth hormones naturally present in meat or added to livestock feed; more extensive antibiotic resistance caused by their use to promote animal growth; a reduction in the food available for human consumption (for example, 97% of the world’s soybeans are used to feed livestock); and higher risks of infections (such as bovine spongiform encephalopathy or “mad cow disease”) due to faulty practices in intensive farming.

Experts agree that we will have to reduce our consumption of red and processed meat in order to live longer, healthier lives, but especially so that our planet is in better condition and can support human activity long term. Eating mostly cereals, fruits, vegetables, nuts, and legumes, and little or no meat is probably the ideal solution to this environmental problem, but for many, red meat is a delicious food that is hard to replace. To satisfy meat lovers who still want to reduce their consumption, companies have recently developed products made only from plants whose appearance, texture and taste are similar to meat, whereas others are trying to produce artificial meat from in vitro cell cultures.

New plant-based patties: Beyond Burger and Impossible Burger
Plant-based burgers have long been available in grocery stores, but these meatless products are intended for vegetarians and consumed mainly by them. New products made from plants, but designed to have the same appearance, texture, and taste as meat have appeared on the market recently. These meat alternatives target omnivorous consumers who want to reduce their meat consumption. Among the most popular products, there is the Beyond Burger, available at the fast food chain A&W and recently in most supermarkets in Quebec, as well as the Impossible Burger, which will soon be on the menu at fast food chain Burger King under the name “Impossible Whopper.”

The main ingredients of Beyond Burger are pea protein isolate, canola oil and refined coconut oil. This food also contains 2% or less of other ingredients used to create a meat-like texture, colour and flavour, as well as natural preservatives (see box). It is an ultra-processed food that does not contain cholesterol, but almost as much saturated fat (from coconut oil) and 5.5 times more sodium than a lean beef patty. Nutrition and public health experts have suggested avoiding coconut oil in order not to increase blood LDL cholesterol (“bad cholesterol”) and maintain good cardiovascular health (see “Saturated fats, coconut oil and cardiovascular disease”). Moreover, the nutritional contribution of these two products is similar (calories, proteins, total lipids).

Beyond Burger ingredients: Water, pea protein isolate, canola oil, refined coconut oil, 2% or less of: cellulose from bamboo, methylcellulose, potato starch, natural flavour, maltodextrin, yeast extract, salt, sunflower oil, vegetable glycerine, dried yeast, gum arabic, citrus extract, ascorbic acid, beet juice extract, acetic acid, succinic acid, modified food starch, annatto.

Impossible Burger ingredients: Water, soy protein concentrate, coconut oil, sunflower oil, natural flavours, 2% or less of: potato protein, methylcellulose, yeast extract, dextrose, food starch modified, soy leghemoglobin, salt, soy protein isolate, mixed tocopherols (Vitamin E), zinc gluconate, thiamine hydrochloride (vitamin B1), sodium ascorbate (vitamin C), niacin (vitamin B3), pyridoxine hydrochloride (vitamin B6), riboflavin (vitamin B2), vitamin B12.

The Impossible Burger is made from soy protein, coconut oil and sunflower oil. It also contains ingredients that are used to create a meat-like texture, colour and flavour, as well as vitamins and natural preservatives. Among the ingredients added to mimic the colour and flavour of meat is soy leghemoglobin, a hemoprotein found in the nodules on the roots of legumes that has a similar structure to animal myoglobin. Rather than extracting this protein from the roots of soybean plants, the manufacturer uses leghemoglobin produced by yeast (Pichia pastoris) in which the DNA encoding for this protein has been introduced. The use of P. pastoris soybean leghemoglobin was approved by the US Food and Drug Administration in 2018. The fact that the leghemoglobin used is a product of biotechnology rather than from a natural source does not appear to pose a particular problem, but some researchers suspect that the heme it contains could have the same negative health effects as those associated with the consumption of red meat, i.e., an increased risk of cardiovascular disease and certain types of cancer. A causal link between heme and these diseases has not been established, but population studies (see here and here) indicate that there is a significant association between heme consumption and a rise (19%) in mortality risk from all causes. In contrast, non-heme iron from food (vegetables and dairy products) is not associated with an increased risk of mortality.

Beyond Burger and Impossible Whopper, served with mayonnaise and white bread, are not suitable for vegans (eggs in mayonnaise) or a particularly healthy option because of the saturated fat and salt they contain. However, the manufacture of these products requires much less energy and has a much smaller environmental footprint than real red meat, which is their strong selling point. According to one study, the production of a Beyond Burger patty generates 90% less greenhouse gas emissions and requires 46% less energy, 99% less water and 93% less arable land than a beef patty.

We believe that it is preferable, as much as possible, to obtain unprocessed fresh plant products and to do the cooking yourself, in order to control all the ingredients and thus avoid ingesting sodium or saturated fat in excessive amounts, as is the case with most ultra-processed products, including these new meatless patties. Fatty and salty foods taste good to a large majority of human beings, and the food industry takes this into account when designing the ultra-processed food products it offers on the market. If you want to eat a “burger” without meat, why not try to prepare it yourself with black beans (recipes here and here), oats, lentils or quinoa?

Production of “meat” in the laboratory
In vitro “meat” production involves culturing animal muscle cells (from undifferentiated cells or “stem cells”) in a controlled or laboratory environment. The first beef patty produced in a laboratory in 2013 cost 215,000 pounds (Can$363,000), but the price has dropped considerably since then. However, this product is not yet ready to be commercialized, as there are still several technological problems to solve before it can be produced on a large scale. Moreover, if the current experimental product can be used to successfully mimic ground meat, we are still far from being able to grow cells in a three-dimensional form that looks like a steak, for example.

The technology could be used to produce, for example, “Fugu” (puffer fish) meat, a delicacy prized by the Japanese, but which can be deadly if the chef or specialized companies do not prepare the fish properly. Indeed, tetradoxine contained in the liver, ovaries and skin of the fugu is a powerful paralyzing poison for which there is no antidote. Laboratory-made fugu meat would not contain any poison and would be safe for consumers.

Another example of an advantageous application would be the production of duck foie gras. A majority of the French (67%) are against the traditional method of production by gavage, which makes the animals suffer. One company (Supreme) is developing a method to obtain fatty liver from isolated duck egg cells.

Other companies are developing methods to produce egg white and milk proteins by fermentation rather than using animals. Although this “cellular agriculture” still seems a little “futuristic”, it could become increasingly important in the food industry and help reduce the production of meat that is harmful to our planet.