The Top Science Papers of 2020 supporting plant-based nutrition
The science in 2020 supporting plant-based nutrition has been overwhelming. Sadly, the global community have not taken enough action to change our broken food system. It was a tough job, but here are my top evidence-based papers.
MILK AND HEALTH: There are so many myths surrounding non-human milk consumption, mostly propagated by the dairy industry. This review paper written by two eminent Harvard Researchers, who are not plant-based themselves, summaries the scientific data on dairy consumption. They reviewed over 100 studies on milk and health and came to the conclusion that dietary guidelines that recommend dairy consumption are not evidence-based. Here is a summary of the paper from one of the co-authors. Below are the main take home messages.
1) Normal growth and development can be obtained throughout childhood without dairy consumption
2) Overall evidence does not support a benefit of higher dairy consumption for prevention of fractures. Milk consumption in adolescence does not prevent fractures in later life and may even contribute to the higher incidence of fractures in countries with the greatest milk consumption.
3) Studies do not support the theory that milk consumption in children or adults helps maintain a healthy body weight.
4) Milk consumption is not associated with better heart health. The effect depends on what dairy is compared to and is replacing in the diet. Dairy consumption is better for heart health than red meat but less beneficial than fish and nut consumption. Impact on mortality is also based on what dairy consumption is compared to. Consuming protein from plant foods is superior to consuming dairy when it comes to reducing mortality.
5) Dairy consumption does not lower the risk of type 2 diabetes.
6) Milk consumption is associated with a higher risk of prostate cancer, especially aggressive and more fatal forms. Dairy also increases the risk of endometrial cancer in women. BUT lowers the risk of colorectal cancer due to the calcium content.
7) Lactose intolerance is common worldwide. Cow’s milk consumption may predispose to allergies, asthma and eczema and may precipitate asthma exacerbations in adults.
8) There is no evidence to suggest organic dairy consumption negates the health concerns related to non-organic milk consumption.
9) Industrial dairy production is a major contributor to greenhouse gas emission, climate change, water use and pollution and antibiotic resistance.
10) In Western, high-income countries, all nutrients found in milk can be obtained from plant sources or supplements, in the case of vitamin D. There is no requirement for humans to consume dairy, which may in fact have negative consequences for health. In low income countries, if the diet is of low quality, dairy can be a source of nutrients.
Check out all the amazing options for plant-based mylks that are now available. Here is a great review of plant-based mylks from ProVeg International.
OMEGA-3 FATTY ACIDS FOR PREVENTION OF CARDIOVASCULAR DISEASE (CVD): There has been much debate over recent years on the benefits of omega-3 fatty acids from fish and supplements for the prevention of CVD. This Cochrane review provides an up to date analysis on this question. Here are the headline findings;
- Long-chain omega-3 supplements of at least 3g/day had little or no effect on all-cause mortality, cardiovascular mortality, cardiovascular events, stroke or arrhythmia. However, the data suggests that increasing long-chain omega-3 intake may slightly reduce coronary heart disease mortality and coronary heart disease events. These effects are very small. 334 people would need to take long-chain omega-3 supplements for several years for one person to avoid dying of coronary heart disease, and 167 people would need to take omega-3 supplements to avoid one person experiencing a coronary heart disease event.
- The only benefit for CVD risk reported was that long-chain omega-3 supplements may reduce triglyceride levels by 15% in a dose-dependent way.
- There is insufficient evidence to support increasing the consumption of oily fish in the diet for CVD prevention.
- Increasing intake of the essential short-chain omega-3 fatty acids found in plant foods, alpha-linolenic acid (ALA), probably makes little or no difference to all-cause mortality, cardiovascular mortality, coronary heart disease mortality and coronary heart disease events. However, increased ALA intake may slightly reduce risk of cardiovascular disease events and arrhythmia. The effects are small; 500 people would need to increase their ALA intake for several years to prevent one person experiencing a CVD event, and 91 people would need to increase ALA to prevent one person experiencing arrhythmia.
Overall, there is insufficent data to support the role of long and short chain omega-3 fat supplementation for cardiovascular health. Of course, getting enough omega-3 in the form of ALA in the diet is essential when consuming a plant-based diet. This daily requirement can easily be met with a tablespoon of flaxseeds or chia seeds a day or 30g of walnuts.
COCHRANE REVIEW ON REDUCING SATURATED FAT INTAKE FOR CARDIOVASCULAR DISEASE (CVD): This year has seen many scientists claim that red meat and saturated fat consumption is not really that bad for health after all. This could not be further from the truth and one has to question underlying motives. The latest Cochrane review on this topic confirms the benefit of reducing saturated fat intake for CVD health. It included 15 randomised studies with around 59,000 participants and showed that reducing intake of saturated fat over a 2 year period reduces the risk of cardiovascular events by 21%. There was a greater benefit in participants with a higher intake of saturated fat at baseline and if the reductions in saturated fat intake was larger, reflected by a greater reduction in blood cholesterol. The naysayers have been quick to point out that there was little impact on all-cause mortality, coronary heart disease and stroke, although, a borderline significant reduction of 10% was observed for myocardial infarction. One of the issues is that many of the studies did not achieve a big enough dietary change. For example, the biggest randomised trial to be included in the analysis, and hence providing the greatest weight to the final result, was the Women’s Health Initiative study. This study did not achieve its aim, which was to reduce fat intake in the intervention arm to 20% of energy intake. So it shouldn’t be thought of as a low fat intervention. This is the trouble with diet interventions. Unless food is delivered directly to the participants, then people can’t and don’t stick to the prescribed diet.
So for me, the take home message has to be that reducing saturated fat intake does benefit cardiovascular health. The greater the reduction, the more you will benefit. Replacing saturated fat in the diet with unsaturated sources of fat and unrefined sources of carbohydrates is optimal. How can this be achieved? No surprises here. Minimise intake of meat, eggs and dairy and ideally cut it out of the diet completely. Don’t forget that some plant sources of saturated fat like coconut and palm oil are also not considered healthy and should be minimised.
TMAO LEVELS PREDICT FOR CORONARY HEART DISEASE. PLANT-BASED DIETS LOWER THIS RISK: A simple conclusion from a well conducted study. 760 women from the Nurses’ Health Study were followed for 14 years. Blood samples were taken at baseline and after 10 years. Those with the highest level of TMAO (trimethylamine oxide) had a greater risk of coronary heart disease. There was also a strong correlation with increasing levels over the 10 year period and an inverse association with decreasing levels — so you can change your risk over time. There was a 58–79% higher risk of developing coronary heart disease compared to those with the lowest TMAO levels.
The lowest levels of TMAO were associated with plant-based eating patterns as assessed by the Alternate Healthy Eating Index and the plant-based diet index.
So what is TMAO and what can we do about it? It is produced from gut bacteria that convert choline and carnitine from eggs and meat to TMA. Once in the bloodstream, TMA is converted to TMAO in the liver. High levels of TMAO not only increase the risk of coronary heart disease but also heart failure, renal failure and type 2 diabetes.
There is good news here. Removing red meat from the diet can bring down TMAO levels within a few weeks. Vegan and vegetarian diets are associated with lower levels of TMAO than omnivorous diet patterns. So you can alter your risk of chronic disease very easily without medications and stents but with diet change. Act now, as this study shows it’s never too late.
PLANT-BASED DIET VS ANIMAL-BASED KETO: The diet wars continue amongst proponents of a plant-based diet and a low-carb, animal-based diet. The ketogenic diet is an extreme version of a low-carb diet, in which the body uses ketones rather than glucose for energy given that carbohydrate intake is severely restricted. Some of the seminal studies on the metabolic effects of different macronutrient combinations has been conducted by Dr Kevin Hall, from the National Institute of Health (NIH). Interestingly, Dr Kevin Hall previously headed up the Nutrition Science Initiative (NSI), founded by the low-carb proponent Dr Gary Taubes. However, when Dr Hall’s research showed the complete opposite of the low-carber’s theory on the causes of obesity, he fell out with the NSI and left and the NSI has since all but collapsed.
Dr Hall conducts very rigorous studies known as metabolic ward studies in which participants are admitted to a hospital ward and live there for a set number of days, with all the food provided and undergo an array of blood and metabolic tests. His previous study showed that a ketogenic diet was associated with an increase in markers of inflammation and in LDL-cholesterol and did not improve insulin sensitivity or glucose regulation.
The current study, funded by the NIH, examined a plant-based diet vs an animal-based ketogenic diet and investigated whether ketosis (the generation of ketone bodies) increased fat loss and suppressed appetite. 20 participants, with a median age of 30 years and a median BMI of 28 were admitted to the hospital for 28 days and followed a healthy low fat plant-based diet (75.2% carbohydrate, 10.3% fat) or a low-carb diet (75.8% fat,10.0% carbohydrate) for 2 weeks and then crossed over for 2 weeks on the opposite diet. The participants were offered twice the amount of food they needed on a daily basis and were asked to eat as much as they wanted (ad libitum). The macronutrinent intakes were kept stable in each group with both groups consuming 15% of energy from protein.
So what happened to the participants? The low fat plant-based diet had a much higher glycemic load and resulted in greater postprandial glucose and insulin levels compared with the low-carb diet. However, fasting glucose and insulin decreased from baseline in both groups but this reduction did not significantly differ between the groups. Following a glucose tolerance test, the low-carb group had a relative impairment of glucose tolerance compared to the plant-based diet group. Energy (calorie)intake during the plant-based diet was spontaneously reduced by ~550–700 kcal/d compared to the low-carb diet with subjects losing weight and body fat. The low-carb group did lose more weight in the first week but this was non-fat mass (water and muscle). There were no significant differences reported in feelings of hunger, fullness, satisfaction, or pleasantness of the meals. Triglycerides increased from baseline with the plant-based diet and tended to decrease with the low-carb diet. Total and LDL- cholesterol decreased significantly on the plant-based diet as compared to both baseline and the low-carb diet. LDL particle number decreased with the plant-based diet and increased with the low-carb diet.
Conclusions: ‘The carbohydrate-insulin model of obesity predicts that consuming a diet with high glycemic carbohydrates results in increased postprandial insulin that drives body fat accumulation thereby increasing hunger and energy intake’. This theory has been disproven by the current study in which participants on a plant-based diet containing foods with high glycemic load consumed less calories and lost more fat compared to the low-carb diet group. In fact the low-carb diet worsened glucose tolerance i.e. increased insulin resistance, and resulted in unfavourable changes in blood cholesterol levels.
Of note, I am only able to locate the pre-print version of this paper so I look forward to reading the fully peer-reviewed version in due course.
WHICH SOURCE OF PROTEIN IS BEST — ANIMAL OR PLANT? Recurrent media stories try and convince us that animal sources of protein are best and of higher quality. Protein quality should not be judged on whether it contains the right levels of all the amino acids and how digestible they are, but on the impact of the protein source on health outcomes. Yet another study this year confirms improved health outcomes when animal protein is replaced by plant protein
The study reports data from the NIH-AARP Diet and Health Study in the US, including more than 400,000 men and women aged 50–71 years at enrollment in 1996 and observed for 16 years.
The results clearly showed that a higher intake of plant protein was associated with a significantly reduced risk of death from all causes and cardiovascular disease. For every 10g/1000kcal intake of plant protein, there was a 12–14% reduced risk of death. Replacing just 3% animal protein with plant protein reduced death by around 10% and replacing both egg and red meat with plant protein was shown to be beneficial.
Why is animal protein harmful? It creates oxidative stress and inflammation; it comes packaged with saturated fat; there is higher exposure to haem iron and AGE’s, which are harmful; it contributes to adverse effects on the gut microbiome and the production of higher levels of TMAO (implicated in atherosclerosis); increased levels of growth hormone such as insulin-like growth factor, implicated in cancer risk; higher consumption of branched chain & sulphur containing amino acids, which have negative health effects.
This it not the first study to show these finding with similar results from the Nurse’s Health Study and Health Professionals follow up study, Adventist Health Study, Japanese and Finnish cohorts and the Netherlands.
When considering food and nutrients, the entirety of the data needs to be considered from observational, mechanistic and interventional studies. All therapeutic diets including the DASH, Mediterranean, vegetarian and whole food plant-based, minimize animal protein and emphasize plant foods with significant improvements in health outcomes. In the absence of malnutrition, no long term study has shown a benefit to increasing protein from animal sources. Don’t fall for media hype. The science is clear. Focus your diet on healthy plant foods. Western societies have a crisis of fibre and phytonutrient deficiency not protein deficiency and in fact we are suffering the consequences of protein excess.
MEAT CONSUMPTION AND CANCER: This paper shows once again that meat consumption is implicated in cancer development. The study analyzed data from 474 996 participants (54% women) in the UK Biobank study, followed for 7 years. Participants were aged 37–73 years and cancer-free at baseline. The results show that a 70g/day higher intake of red and processed meat was associated with a 20–40% increased risk of colorectal cancer. Although the association was less robust, red meat consumption was shown to increase the risk of prostate cancer by 18%. The data also suggested increased risk for breast cancer (10–14%) and endometrial cancer (30–48%) with higher intakes of meat, but these associations were attenuated after adjustment for BMI, suggesting overweight/obesity are likely to be causing the association. In addition, a 20% increase in risk of cancer of the lymphatic and haematopoietic tissue was found with poultry intake, although the results did not hold true after correcting for multiple testing. So once again — moderation is not the answer. 70g of processed meat is only 2 slices of bacon or 1.5 sausages.
This excellent guideline from the American Cancer Society summarises diet and physical activity guidelines for cancer prevention. The data are clear. The best foods for cancer prevention are fruits, vegetables, whole grains, beans and nuts — all the plants!
RANDOMISED STUDY OF A LOW-FAT VEGAN DIET: There are very few robust, randomised studies of a low-fat vegan diet. Most of the good studies come from PCRM. Their latest study does not disappoint and is published in a highly reputable journal thus elevating its importance.
In this study, participants aged 25–75 years with a body mass index of 25–40 were recruited through an advertising campaign. The final 244 participants selected were randomised to follow either a low-fat, vegan diet or make no dietary changes for 16 weeks. The intervention diet (approximately 75%of energy from carbohydrates, 15%protein, and 10% fat) consisted of vegetables, grains, legumes, and fruits without animal products or added fats. Vitamin B12 was supplemented (500 μg/d). The intervention group attended weekly classes for detailed instruction and cooking demonstrations and received printed materials and small food samples. No meals were provided. For both groups, alcoholic drinks were limited to 1 per day forwomen and 2 per day for men. All participants were asked to maintain their usual exercise habits and medications unless modified by their doctor. At the beginning and the end of the 16 weeks researchers measured body weight, body fat composition, insulin sensitivity, and the thermic effect of food (postprandial metabolism). In a subset of participants (n = 44), researchers also measured fat in the liver and muscle cells, which contributes to insulin resistance and fatty liver disease, using proton magnetic resonance spectroscopy.
The results showed that the vegan group lowered their body weight by 6.4 kg (about 14 pounds) and the fat inside the liver and muscle cells by 34% and 10%, respectively. They also increased their after-meal metabolism by 18.7%. There were no significant changes in the measured parameters in the control group. The decrease in liver and muscle fat correlated with improvements in insulin resistance.
Things to note, calorie intake based on self-reported assessment, reduced in both groups but more so in the vegan group with a difference of 355kcal/day between groups. Thus the better weight loss achieved was due to a combination of reduced calorie intake and increase postprandial energy expenditure. As expected, the vegan group had a higher carbohydrate and fibre intake and lower fat intake during the 16 weeks compared to the control group. It’s worth noting though that participants were not asked to restrict calorie intake and could eat as much as they liked.
These findings are in line with previous studies that have shown a plant-based/vegan diet naturally lowers calorie intake, increases fibre intake, reduces weight and insulin resistance and lowers fat accumulation in the cells. These are all key mechanims by which chronic illness can be prevented.
The authors conclude ‘A low-fat plant-based diet is an effective tool for reducing body weight and increasing insulin sensitivity and postprandial metabolism’.
PLANT-BASED MEAT ALTERNATIVES (PBMA) AND CARDIOVASCULAR DISEASE (CVD) RISK FACTORS: We know that PBMA’s are better than eating animal meat for the environment and of course the animals. But to date there are very little data on the human health impacts. It has been suggested that these PBMA are ‘healthier’ as many are lower in saturated fat, don’t contain inflammatory animal protein and some have fibre too. However, most are still considered ultraprocessed foods, which we know can have detrimental health effects and many have a high sodium content. So its great to see a study that compares PBMA’s with meat and measures biomarkers related to CVD. The primary study outcome was differences in serum TMAO after 8 weeks of PBMA (Plant) compared to animal meat (Animal). Secondary outcomes were differences in fasting plasma IGF-1 concentrations, metabolic markers (blood lipids, glucose, and insulin), blood pressure, weight, and microbiota composition.
The study highlighted was a single-site, randomised crossover trial with no washout period. 36 participants were instructed to consume ≥2 servings/day of Plant compared with Animal for 8 weeks each, while keeping all other foods and beverages as similar as possible between the 2 phases. All Plant products were supplied by Beyond Meat. All Animal products were supplied by a San Francisco–based organic foods delivery service; the red meat sources were grass-fed.
Compared to the organic, grass-fed animal meat, PBMAs led to significant reductions in TMAO, LDL and body weight. It was interesting that the reduction in TMAO depended on the order of intervention with TMAO concentrations significantly lower for those that received the Plant diet second. A wash out period before the crossover may have been a useful part of the study to understand this order effect. Fasting concentrations of IGF-1, insulin, glucose, HDL cholesterol, and triglycerides, and blood pressure, were not significantly different between the Plant and Animal phases.
Now we have to be skeptical given the study was funded by an unrestricted grant from Beyond Meat. But here are some relevant points;
1) Beyond Meat was not involved in study design or analysis of the data. 2) The lead author, Christopher Gardner, is a highly respected and experienced scientist and nutrition researcher 3) The study protocol, including statistical analysis, were published online before the study commenced 4) The results are entirely plausible 5) The study design is robust and the non-meat aspects of the diets were controlled for as much as possible in free living conditions 6) The study compared plant-based meat to animal-based meat, so they chose to compare like for like as much as possible. They could have biased the results by comparing plant-based meat to processed meats like bacon, sausage and deli meats for example, but instead chose to compare to organic, grass fed meat which would, at least in theory, give ‘better results’ than factory farmed meat or processed meat.
So all in all, these are encouraging results. Of course common sense tells us that the best diet is one composed of minimally processed whole plant foods and these newer processed PBMA’s should be kept to a minimum in the diet.
American Medical Association Calls for Dietary Guidelines To Indicate ‘Meat and Dairy Products Are…
In response to the Scientific Report of the 2020 Dietary Guidelines Advisory Committee (DGAC), the American Medical…
THE AMERICAN MEDICAL ASSOCIATION CALLS FOR MEAT AND DAIRY TO BE OPTIONAL IN THE US DIETARY GUIDELINES: We are eagerly awaiting the 2020–2025 US dietary guidelines has they usually have a global impact. The report from the Scientific Advisory Committee has been published. In the meantime, The AMA have endorsed the wealth of evidence on diet and health and call for meat and dairy to be optional in the new dietary guidelines. Meat heavy diets are contributing to obesity, CVD, cancer and type 2 diabetes. Dairy consumption is just not necessary and guidelines recommending the continued consumption excludes communities of colour who are more likely to be lactose intolerant. This is a very welcome recommendation and in line with the 2019 Health Canada dietary guidelines that is a plant-predominant diet in which dairy has been completely removed.
PLANT-BASED DIETS FOR KIDNEY DISEASE: This is a phenomenal contribution to the literature by fellow plant-based physicians.
The topic of plant-based diets (PBD) for kidney disease has not been discussed enough and continues to be clouded by prevailing myths. This paper brings us right up to date and it is clear that PBDs should be front and centre of a lifestyle approach to maintaining kidney health.
Why? PBDs prevent the very causes of kidney failure — hypertension and type 2 diabetes. If you have established kidney failure, PBDs will slow the progression because of its lower acid load, lower protein and higher fibre content. All these factors reduce the load/strain on the kidneys. PBDs reduce the level of uraemic toxins, promote a healthy gut microbiome and reduce inflammation.
If you have established kidney disease, fruits and vegetables can be as beneficial or more so than sodium bicarbonate to reduce acid load and PBDs may help prevent the need for dialysis. The concerns about high potassium and phosphate and low protein in PBDs have been overstated and with some adjustments, PBDs can be suitable for those on dialysis too.
All in all, this paper should be practice changing around the world. Of course, any diet change in a patient with kidney disease should be supported by a specialist dietitian or healthcare professional. Please read the full paper, which is free online.
FRUIT AND VEGETABLE CONSUMPTION AND TYPE 2 DIABETES: This paper reports data from the EPIC-InterAct study and includes 9754 incident cases of type 2 diabetes in a subcohort of 13662 participants. It investigates objectives plasma biomarkers of fruit and vegetable intake and risk of type 2 diabetes. Previous studies that have investigated the association between fruit and vegetable intake and the risk of type 2 diabetes have relied on self-reported dietary questionnaires, with inconsistent findings and only weak reductions in risk (7–10% reductions). To overcome the issues with measuring intake from food frequency questionaires, this study measured plasma levels of vitamin C and carotenoids. In the analysis, higher plasma concentrations of vitamin C, total carotenoids, alpha-carotene, beta-carotene, and an overall biomarker score was associated with a 42–55% reduction in risk of type 2 diabetes, while higher concentrations of lycopene, lutein, and beta-cryptoxanthin was associated with a 21–35% reduction in risk. The findings strongly suggest that higher fruit and vegetable consumption is inversely associated with the incidence of type 2 diabetes, regardless of whether this increase in consumption is from a level below or above the recommended five a day threshold. The authors conclude; ‘The public health implication of this observation is that the consumption of even a moderately increased amount of fruit and vegetables among populations who typically consume low levels could help to prevent type 2 diabetes’.
This study completely dispels the myth that eating fruit can cause type 2 diabetes because of the high fructose content. This makes no sense in the context of the data we now have and on the basis of just plain old common sense. The fructose content is irrelavant when fruit is considered as a whole package with fibre and phytonutrients. In fact, not eating enough fruits and vegetables is detrimental to health and there is no such thing as eating too much fruit.
COULD CRUCIFEROUS AND FERMENTED VEGETABLES HELP TO REDUCE MORTALITY FROM COVID-19? This is the hypothesis proposed in this paper. A number of studies have suggested the dietary factors may be important in reducing the morbidity and mortality from SARS-CoV-2 infection. In part because unhealthy diets are associated with increased risk of chronic health conditions, including overweight/obesity, cardiovascular disease and type 2 diabetes that predict for a worse outcome. In addition, healthy diets centred around whole plant foods are better at supporting the immune system and reducing inflammation, oxidative stress, insulin resistance and enhancing endothelial dysfunction, all thought to be important for recovery from the virus. Based on ecological studies, countries consuming the most cruciferous and fermented vegetables have a lower death rate from COVID-19. A study in pre-print found that For each g/day increase in consumption of fermented vegetables of the country, the mortality risk for COVID-19 was decreased by 35.4%. A further study showed that the consumption of cabbage and cucumber reduced the risk of death from COVID-19. These studies are hypothesis generating but can not yet prove a direct effect.
The highlighted review proposes plausible mechanims by which fermented and cruciferous vegetables may be important. Within fermented foods there are live bacteria and it is particularly the Lactobacillus species that are dominant. These bacteria have been associated with improved gut health, immune function and reduced inflammation and oxidative stress. Cruciferous vegetables also have potent anti-inflammatory and anti-oxidant effect in part due to the generation of sulforaphane. Both fermented and cruciferous vegetables are thought to act by upregulating the anti-oxidant transcription factor Nrf2.
Although no recommendation can be made from these early data, the consumption of both fermented vegetables and cruciferous vegetables are definitely good for general health. So no harm in loading up on cabbage, kale, broccoli and cauliflower or kimchi, sauerkraut and water kefir, whilst we await further data.
VEGAN AND VEGETARIAN DIETS AND BONE HEALTH: For obvious reasons this study has caused waves in the media and vegan community. The paper brings us a new analysis from the EPIC-Oxford study, one of the longest running and largest studies investigating the health of vegetarians and vegans. There is a lot to digest in the paper with some quite complicated analysis.
This was a robust study design with rigorous analysis of the data. Two of the authors are vegan. The results show an increased rate of fracture in those not consuming meat. This is not exclusive to vegans and includes vegetarians and fish eaters, but the effect is more pronounced in the vegan group. For vegans the impact is greatest for hip fractures with a 2.3 times elevated risk compared to meat eaters. Vegans have a 1.43 times elevated risk of developing any fracture compared to meat eaters. The points of interest are that bone mass index (BMI) had a major influence on fracture risk with a BMI less than 22.5 associated with the increased risk. For vegans with a BMI greater than 22.5 this risk disappears. The fracture risk was also only increased in women (who made up more than two-thirds of the participants) and not men. Vegans in this study had a lower than recommended calcium intake and a lower use of HRT in women, factors that are relevant to the risk of bone fractures. The mean calcium intake for vegans was around 600mg so not meeting UK recommendations for 700mg per day. We also know from prior reports from the EPIC-Oxford cohort that the vegans had lower B12 and vitamin D intakes compared to the non-vegans. Only around 50% of vegan participants in this study were taking dietary supplements, which means that 50% were relying on food sources of vitamin B12 and vitamin D, which we know are inadequate. These participants were recruited in the 1990’s at a time when fortification of plant-based alternatives was not common, in contrast to the fortification of cow’s dairy with vitamin D for example.
The major limitation is that the study can not tell us the cause of the fractures i.e. are they due to poor bone health or due to accidents. There was also no determination of bone mineral density. The study did not correlate fracture rates with vitamin D status, a major factor in bone health. So, overall the study does not prove a causal relationship between diet and fractures but an association. Having said that, we need to pay attention to these results rather than discount them.
For me the take home messages are the importance of adopting a healthy vegan diet, paying attention to nutrients such as calcium, zinc, B12, vitamin D. A healthy vegan diet is one that is composed of a variety of fruits, vegetables, whole grains, beans, nuts and seeds and minimises processed/packaged foods. It’s also helpful to incorporate fortified foods and drinks such as soya milk, yogurt and calcium-set tofu. Weight bearing physical activity and muscle strengthening are also vitally important for bone health and may need to be emphasised more for those on a 100% plant-based diet, along with other healthy lifestyle practice that impact bone health; avoiding alcohol and tobacco smoking, limiting caffeine and fizzy drinks. It may also be beneficial to aim for the middle of the BMI range rather than a BMI of <20.
We must not forget that the same EPIC-Oxford study has shown us that a vegan diet is associated with around a 50% reduction in risk of high blood pressure, significantly lower levels of blood cholesterol, a 25–30% reduction in ischaemic heart disease (this includes vegetarians as well), 19% reduction in cancer risk and a 30–40% reduction in risk of type 2 diabetes in those not eating meat. These are all major causes of death and disability in the UK and a far greater risk to personal and public health than bone fractures.
PLANT-BASED DIETS FOR CHILDREN: This new factsheet on plant-based eating for children is excellent and endorsed by the BDA, the professional body representing dietitians in the UK. I strongly urge you to download, read and keep for future reference. It covers all the essential nutrients necessary for growth and development, dispells myths on the need for dairy and fish in the diet and provides information on supplements. The conclusion ‘Reducing consumption of animal-source foods at a population level in the UK, and prioritising high quality plant foods in the diet will lead to better outcomes for people and the planet. …
THE SIXTH MASS EXTINCTION: We were warned back in 2015 that we have entered the sixth mass extinction. Did we listen? Did we take action? It seems not. The same scientists published research in 2020 showing that the loss of species from this planet is accelerating and this poses a direct threat to human existence on the planet. Human impact on the planet has led to hundreds of species becoming extinct, with even more at the brink of extinction. They report that in the 20th century, around 543 land vertebrates became extinct and they predict that in the next 2 decades the same number again could also suffer the same fate. This loss of wildlife, a result of population growth, habitat destruction, the wildlife trade, pollution and climate change, poses an ‘existential threat to civilization’. The legal and illegal wildlife trade is responsible for many of the endangered species and the COVID-19 pandemic is just one disastrous consequence. Their warning is stark and clear; ‘There is time, but the window of opportunity is almost closed. We must save what we can, or lose the opportunity to do so forever. There is no doubt, for example, that there will be more pandemics if we continue destroying habitats and trading wildlife for human consumption as food and traditional medicines. It is something that humanity cannot permit, as it may be a tipping point for the collapse of civilization. What is at stake is the fate of humanity and most living species. Future generations deserve better from us’.
As individuals, the most important action we can take to help reverse this ecological crisis is to adopt a plant-based diet. This was endorsed by Sir David Attenborough in the documentary version of his witness statement — A life on our planet.
SUSTAINABLE DIETS; HOW ARE WE DOING?: Our diet choice is no longer just a matter for personal health. The global food system is a major contributor to climate change with animal agriculture being particularly harmful due to its contribution to greenhouse gas emissions, land use change, loss of biodiversity, species loss, water pollution etc. Livestock farming and aquaculture is responsible for around 58% of the greenhouse gas created by global food, and takes up 80% of farmland despite contributing just 18% of the world’s calorie intake. A shift to a plant-based food system is accepted as necessary to meet the Paris Agreement and Sustainable Development Goals. So how are we doing? Sadly not well at all. This stark report from the Eat Forum highlights the lack of progress since the publication of the Eat-Lancet commision report on healthy, sustainable diets in January 2019. The current report focuses on the G20 countries and concludes that dietary habits in these countries are destroying the planet. If the whole world ate in this way we would need the resources of 7 planets to feed the global population. If these countries continue to eat in such a way then we will not be able to keep global warming below 1.5°C. Food related green house gas emissions need to be cut in half by 2050 to keep us within planetary boundaries. The good news is that what is good for the planet is also good for our health. Centring our diet around fruits, vegetables, wholegrains, legumes, nuts and seeds whilst reducing drastically or eliminating animal-derived foods will improve personal health and help heal the planet for future generations.
PREVENTING THE NEXT PANDEMIC: 2020 will be remembered for the COVID-19 pandemic that caused a global health and economic crisis. The UN environment programme warns us that unless we address the root cause of pandemic infections i.e. wildlife trade, destruction of animal habitats and factory farming — future pandemics are inevitable. They lay out recommendations for decision makers and identify seven human-meditated factors that are driving the emergence of zoonotic infections. 1) increasing human demand for animal protein; 2) unsustainable agricultural intensification; 3) increased use and exploitation of wildlife; 4) unsustainable utilisation of natural resources accelerated by urbanisation, land use change and extractive industries; 5) increased travel and transportation; 6) changes in food supply; and 7) climate change.
We need to first focus on our own actions and then continue to campaign and demand change from those in power. Lead by example and others will follow. We have the answers to many of our global problems but we still need to unify in implementing the necessary actions. Delaying these difficult decisions will be catastrophic for human existence.
I hope the papers presented persuade you that for your own health and the health of the planet, a plant-based diet is the only choice and that you can be confident that a 100% plant-based diet can help maintain optimal health.
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