We put 10 of the most common nutrition questions to Prof Grant Schofield and Dr Caryn Zinn. Here’s question 5: Is eating plants only healthier than eating meat and plants?
This is a massive, controversial question. To find the answer, we need to first of all look at populations of people and ask, the people who only plants, are they healthier than the people who eat plants and meat? And at first glance that appears to be true – that the plant eaters are generally healthier than the non-plant eaters. Unfortunately, that study is massively confounded by the fact that there’s a healthy eating effect of choosing plant-based eating.
When looking at populations, people who go for the plant-based or vegan diet tend to have other really positive health behaviours going on. They generally smoke less, and they exercise more. The overall quality of unprocessed and less ultra-processed food is better. That’s why these diets give the impression of imparting a greater health benefit than eating mostly meat.
To find out which way of eating is healthier, we would need an experiment where we randomise people into equal nutrient quality diets, but one eating plants only and one eating plants and meat. To our knowledge, no such experiment has been done.
“My own scientific opinion is that you actually run the risk of nutrient deficiencies, being a human omnivore. Now, it seems to me that through our evolutionary heritage, humans are obligate omnivores. They eat plants and animals and when you look at the nutrient profiles coming from fresh plants and animals, those satisfy what we need as humans to be healthy and happy. So, avoiding meat might run the risks of such deficiencies,” says Prof Grant Schofield.
Bottom line, we think you can be equally healthy as a plant-only versus a meat and plants eater, as long as you supplement properly and do your homework. And as long as you’re eating whole, unprocessed foods and you’re looking after yourself in both conditions.
Prof Grant Schofield and Dr Caryn Zinn are the lead instructors in the Certificate of Advanced Nutrition.