The pressure to move to plant-based and vegan diets for the good of the planet has several nutritional drawbacks. This article looks at how it will worse the already-low intake of essential nutrient choline, involved in brain health.
Many other key brain nutrients in addition to choline are difficult if not impossible to obtain in sufficient quantities from vegan, many vegetarian and other 'plant-based diets'. Examples include Vitamin B12, the long-chain omega-3 fatty acids EPA and DHA, active Vitamin A, Vitamin D3, Vitamin K2, zinc and iron.
Despite this, 'plant-based' diets are increasingly promoted in the media as the best solution to the huge challenge of feeding an ever-increasing population on a finite planet.
Earlier this year, the EAT-Lancet Commission's 'flexitarian' recommendations received so much media coverage it would be easy to think they were official public health dietary guidelines. Instead, of course, they reflect the opinions of the academic researchers involved, along with those of some of the food companies working with the EAT Foundation.
Eat-Lancet’s dietary recommendations were put forward as the only way to save the world while keeping everyone healthy. However, according to several well-informed critiques, which explain and reference in detail the actual scientific evidence, the largely vegan/vegetarian diet recommended by the EAT-Lancet consortium would be likely to do exactly the opposite - not least owing to the highly processed oils and starches it included.
Calls to eat more vegetables, fruits, nuts and seeds are not controversial - provided these are not in ultra-processed forms. These foods are seriously lacking from the typical modern, western-type diet, and provide much-needed dietary fibre, as well as many important nutrients and phytonutrients.
But animal-derived foods (i.e. fish, meat, eggs and dairy products) remain the richest sources of almost all essential nutrients. Any diet that excludes these foods (or absolutely minimises them, as the 'EAT' diet does) will therefore inevitably make it more difficult - and for some nutrients such as Vitamin B12, impossible - to obtain adequate intakes without supplementation and/or fortification.More articles on the potential risks vs benefits of plant-based and vegan diets can be found here.
The momentum behind a move to plant-based and vegan diets for the good of the planet is commendable, but risks worsening an already low intake of an essential nutrient involved in brain health, warns a nutritionist in the online journal BMJ Nutrition, Prevention & Health.
To make matters worse, the UK government has failed to recommend or monitor dietary levels of this nutrient—choline—found predominantly in animal foods, says Dr. Emma Derbyshire, of Nutritional Insight, a consultancy specialising in nutrition and biomedical science.
Choline is an essential dietary nutrient, but the amount produced by the liver is not enough to meet the requirements of the human body.
Choline is critical to brain health, particularly during fetal development. It also influences liver function, with shortfalls linked to irregularities in blood fat metabolism as well as excess free radical cellular damage, writes Dr. Derbyshire.
The primary sources of dietary choline are found in beef, eggs, dairy products, fish, and chicken, with much lower levels found in nuts, beans, and cruciferous vegetables, such as broccoli.
In 1998, recognising the importance of choline, the US Institute of Medicine recommended minimum daily intakes. These range from 425 mg/day for women to 550 mg/day for men, and 450 mg/day and 550 mg/day for pregnant and breastfeeding women, respectively, because of the critical role the nutrient has in fetal development.
In 2016, the European Food Safety Authority published similar daily requirements. Yet national dietary surveys in North America, Australia, and Europe show that habitual choline intake, on average, falls short of these recommendations.
"This is....concerning given that current trends appear to be towards meat reduction and plant-based diets," says Dr. Derbyshire.
She commends the first report (EAT-Lancet) to compile a healthy food plan based on promoting environmental sustainability, but suggests that the restricted intakes of whole milk, eggs and animal protein it recommends could affect choline intake.
And she is at a loss to understand why choline does not feature in UK dietary guidance or national population monitoring data.
"Given the important physiological roles of choline and authorisation of certain health claims, it is questionable why choline has been overlooked for so long in the UK," she writes. "Choline is presently excluded from UK food composition databases, major dietary surveys, and dietary guidelines," she adds.
It may be time for the UK government's independent Scientific Advisory Committee on Nutrition to reverse this, she suggests, particularly given the mounting evidence on the importance of choline to human health and growing concerns about the sustainability of the planet's food production.
"More needs to be done to educate healthcare professionals and consumers about the importance of a choline-rich diet, and how to achieve this," she writes.
"If choline is not obtained in the levels needed from dietary sources per se then supplementation strategies will be required, especially in relation to key stages of the life cycle, such as pregnancy, when choline intakes are critical to infant development," she concludes.