A review of the week’s plant-based nutrition news 12th December 2021
This week I cover vegan diets in children, plant-based diets and migraines, food additives and gut health, plant-based meat alternatives and a one health approach to healing humans and the planet.
VEGAN DIETS FOR CHILDREN: The adequacy of vegan diets for children continues to be a topic of debate despite the fact that many dietetic organisations have agreed that when well planned, vegan diets can support health at all stages and ages of life. The VeChi diet study conducted in Germany has provided us with welcome data on the health of modern day vegan children. I have previously covered their studies on growth, development, macronutrient intake and cardiovascular risk factors for children aged 1–3 years and 5–10 years. The results have so far been very reassuring and confirm the adequacy of a healthy, plant-based diet.
This new analysis from the VeChi study included 164 omnivores, 127 vegetarians, and 139 vegans aged 1–3 years and was conducted between October 2016 and April 2018. The study specifically addressed micronutrient sufficiency in the different diet patterns. Diet was assessed over 3 consecutive days by parents who weighed and recorded all the food and beverages consumed.
Without supplementation, vegan children had the highest median intake of vitamins E, K, B1, B6, folate, and C, while omnivores had the highest intake of vitamins B2 and B12. With appropriate supplementation, which 97.1% of vegans were doing, the vegans also consumed the most vitamin B12 and D. Regarding minerals, vegans consumed the most potassium, magnesium, and iron, while omnivores consumed the most calcium and iodine. Without supplements, iodine and vitamin D intake failed to reach recommendations in all diet groups as did calcium, vitamin B2, and B12 in vegans.
All groups consumed a similar amount of fat, but vegans consumed the most polyunsaturated fatty acids and the least saturated fat. Omnivorous children exceeded the recommended intake of saturated fat (14% of calorie intake) also exceeded national recommendation on maximum cholesterol intake. Vegans consumed the most ALA (short chain omega-3 fatty acid), but the least EPA and DHA (long chain omega-3 fatty acids).
Overall, the study showed that vegans had the highest intake of several vitamins and minerals. However, nutrients that require attention include vitamin B2, vitamin B12, calcium and iron (iron intakes tend to be higher but absorption is less so may result in lower blood levels). All diet patterns require attention to obtain enough vitamin D and iodine. Vegan children had a more favourable profile of fat consumption that would be predicted to be beneficial for future cardiovascular health.
The authors conclude that vegan diets should emphasise foods containing vitamin B2 (e.g., green vegetables, nutritional yeast, nuts, legumes and fortified dairy alternatives), iron (and in combination with foods that increase the bioavailability of iron), ensure adequate iodine intake (iodised salt or supplement), vitamin B12 supplement and calcium-fortified dairy alternatives. Vitamin D supplementation is required in all diet groups when sun exposure is inadequate.
Much of this information is not going to surprise those already following a plant-based diet. The issue of vitamin B2 or riboflavin adequacy is not often discussed. The recommended dietary allowance for age 1–3 years is 500mcg. The vegan children in this study were consuming a medium of 429mcg (325–537), so not far off the recommended intakes. Vitamin B2 can be easily obtained from vegan sources including oats, almonds, soya milk (both unfortified and fortified) and green vegetables.
All in all a very reassuring study confirming that regardless of diet pattern attention needs to be paid to critical nutrients.
PLANT-BASED DIET AND MIGRAINES: It was interesting to see that this case report made the mainstream media. No one who is already consuming a plant-based diet was surprised to read about these supposed ‘remarkable results’. Many people, including from our own organisation, have reported drastic improvements or elimination of migraines on a whole food plant-based diet. Dr Leila Dehghan, PBHP UK nutritionist and education lead has shared her story of healing from migraines using a whole food plant-based diet.
The current case report is remarkable in that the patient had had to rely on medication for 12 years but within 3 months of a whole food plant-based diet, emphasising dark leafy greens, the migraines had completely resolved and he has now been free of medications for 7.5 years.
We have known for a while that certain foods can be triggers for people with migraines, although not in every case. There have been a number of studies investigating diet, foods and individual nutrients for managing migraine symptoms. For example, supplementation with coenzyme Q10, omega-3 fatty acids, and magnesium have been shown to be beneficial, but none result in elimination of the condition and none have enough evidence to be incorporated into clinical guidelines. Many patients try eliminating certain foods that commonly trigger migraines including chocolate, cheese, alcohol, coffee and citrus.
The most likely reason why a plant-based diet is a good option for people with migraine is because it is known to lower inflammation and oxidative stress, both mechanisms thought to be involved in the development of migraine disorders. There is one randomised crossover trial of a low fat plant-based diet from the Physicians Committee for Responsible Medicine which reported reduced migraine pain, duration and need for pain medication. The current case report demonstrates what is possible when adopting a whole food plant-based diet and that it is never too late to gain a benefit.
FOOD ADDITIVES AND GUT HEALTH: It is not surprising to learn that food additives can adversely affect health but its always valuable to be able to demonstrate how this occurs. Carboxymethylcellulose (CMC) is a synthetic food additive and emulsifier, which is added to many processed foods to enhance texture and promote shelf life. Despite is widespread use, very few studies have been performed to assess its impact on health.
This study was a randomised, double blind controlled feeding study in healthy volunteers. Participants were provided with an additive-free diet (n=9) or an identical diet supplemented with CMC (n=7) for 11 days. The impact of the two diets on intestinal bacteria and metabolites was assessed.
The results showed that CMC consumption changed the make-up of bacteria populating the colon, including a reduction in bacterial diversity. Furthermore, faecal samples from CMC-treated participants showed a depletion of beneficial metabolites, particularly short chain fatty acids and free amino acids, that are required to maintain a healthy colon and influence health more widely. The researchers also performed colonoscopies on participants at the beginning and end of the study and showed that in some, but not all, participants consuming CMC displayed gut bacteria encroaching into the mucus layer, which has previously been observed to be a feature of inflammatory bowel diseases and type 2 diabetes.
The study should act as a warning as it shows that food additives in certain individuals can have an adverse effect in a short period of time. Of note, the dose of CMC used was much higher than most people might be consuming and would represent the level of exposure if most of the diet was obtained from processed foods. Although longer and larger studies would be desirable, this study provides a plausible hypothesis by which our reliance on processed and ultra-processed foods may be linked to a rise in inflammatory conditions in the bowel and the rest of the body. As always, the precautionary principle should apply and our diets should be centred around foods known to promote health.
We have shared a very useful factsheet on the health impacts of ultra-processed foods on our website.
NUTRITIONAL QUALITY OF PLANT-BASED MEATS: Like them or not, plant-based meat alternatives (PBMAs) are here to stay. Despite the exponential rise in these newer, more processed PBMAs that try and emulate the taste and texture of animal flesh, there has been very little research into their nutritional quality and health impacts. Last year we saw the publication of the first randomised clinical trial of PBMAs, specifically Beyond Meat products. which seemed to have some small but measurable benefits compared to organic, grass-fed beef.
This new study reports a cross-sectional survey of 207 PBMAs and 226 meat products available from 14 retailers in the UK. The PBMAs were from a variety of stores including Aldi, Asda, Iceland, Lidl, Morrisons, Sainsbury’s, Tesco, The Co-operative, Waitrose, Marks & Spencer, Boots, Holland & Barrett, Whole Foods, and Planet Organic. The study included both vegetarian and vegan products and focused on those products designed to mimic the taste, texture, and full consumer experience of meat and made of fungal or plant-based ingredients. The study excluded tofu, tempeh, falafels, vegetable fritters, vegan cheese and ready meals. Researchers collected data on on calorie content, total and saturated fat, protein, fibre, and salt per 100g from product packaging and calculated the nutrient profile of each product. These data were compared to meat products from Tesco.
The results showed that compared to meat, PBMAs had a significantly lower calorie content, total fat, saturated fat, protein, and significantly higher fibre content. However, salt content was significantly higher in most PBMAs products. Based on UK criteria, meat products were more often classified as ‘less healthy’ compared to PBMAs (40% vs 14%) and more meat products were considered high in either total fat, saturated fat, or salt compared to PBMAs (46% vs 20%). Most PBMAs did not meet the current UK salt targets.
Overall, it is likely that PBMAs are a better option for personal health than meat and it is more certain that their production is better for planetary health and of course non-human animals. These products are not necessary in the diet, but as a society we have got used to eating these types of processed foods. If you are going to buy these products, be mindful of the salt content and choose those that are higher in fibre and lower in saturated fat.
Registered plant-based dietitian Lisa Simon has written a useful article on PBMAs for our website, which you can find here.
ONE HEALTH APPROACH TO HEALTHCARE: The One Health (OH) approach holistically considers interlinked complex health issues between humans, animals and the environment. Life Cycle Assessment (LCA) is a standardised method to evaluate impacts from all food supply chain stages (i.e., from farm to-fork). This unique study uses a LCA perspective to assess the sustainability of food production and consumption and considers the impact from a OH perspective. Impact on human health is estimated according to risk factors for non-communicable diseases. Animal welfare is measured as animal life years suffered, loss of animal lives and loss of morally-adjusted animal lives.
This study from Germany compared the impact of the current Western diet pattern with three different diet scenarios: a shift to the recommendations of the German Nutrition Society (DGE), a Mediterranean diet with more fish and seafood, and a vegan diet. Impacts on environment, human health and animal welfare were assessed.
The results showed that each of the three diets would be better from a One Health perspective. However, each diet pattern had different trade offs. For example, the vegan diet scored best in most areas. However, the production of vegan food involved increased water use. The Mediterranean diet also resulted in increased water requirements due to the high amount of nuts and vegetables. In addition, if meat was completely replaced by fish, there was a negative effect on animal welfare as fish and seafood are much smaller than cows or pigs, therefore considerably more animals suffer as a result of this diet. The increased consumption of honey, which requires intensive management of bee colonies, also has a negative impact.
Overall, the vegan diet was the most beneficial scenario with greater than 50% reduction in environmental impacts (except water use), the greatest benefits to human health and of course for the animals. Reducing consumption of ready-to-eat meals and highly processed foods was also shown to have benefits from the OH perspective.The authors state; ‘It’s therefore beneficial to meet less of your overall protein needs from animal sources’.
Given the interconnected crises related to the food system, including the dramatic loss of biodiversity, pandemic risk and antibiotic resistance, we can no longer ignore the impact of diet choice on humans, non-human animals and the planet. A vegan diet is the only diet to adequately address all three aspects of the one health perspective.
There is an interesting written and podcast discussion this week in the Nature Journal on healthy diets for people and planet.