Summary of some studies comparing vegetarians, vegans and omnivores

  • Vegans live longer – lower BMI, cholesterol and glucose versus omnivores. Reduced risk of cardiovascular disease and cancer compared to omnivores. Dinu M, et al. vegetarian, vegan diets and multiple health outcomes: a systematic review with meta-analysis ofobservational studies. Crit Rev Food Sci Nutr. 2016 Feb 6:0
  • But why?
  • Micronutrient status in different diets
    • Omnivores had low intake of Magnesium, vitamin C, vitamin E, Niacin and folic acid
    • Vegans had low zinc, calcium, vitamin D, B12, iodine, selenium and protein
    • Vegetarians had low vitamin iodine, selenium, B6, B3 and protein

Schupbach R, et al. Micronutrient status and intake in omnivores, vegetarians and vegans in Switzerland. Eur J Nutr. 2015 Oct 26

Antioxidant status sim8ilar between groups. Halda S, et al. Influence of habitual diet on antioxidant status: a study in a population of omnivores and vegetarians. Eur J Clin Nutr. 2007 Aug; 61(8):1011-22.

Elorinne AL, et al. Food and Nutrient intake and Nutritional Status of Finnish Vegans and non-vegetarians. PLOS ONE. February 3, 2016

Kristensen NB, ety al. Intake of Macro- and Micronutrients in Danish vegans. Nutrition journal (2015) 14:115

    • Vegans have the most acidic diet. Omnivores are apparently acidic because of the consumption of meat and dairy as “acidic foods” (we discuss the acid / alkaline diets in the podcast). The acid they are referring to is uric acid. Studies comparing the different diets has shown the vegan diet to be the most acidic with the highest levels of uric acid. The best diet for acidity is a predominate vegetarian diet supplemented with fish for protein. Schmidt JA, et al. Serum uric acid concentration in meat eaters, fish eaters, vegetaruians and vegans: a cross-sectional analysis in the EPIC-Oxford cohort. Plos One. 2013; 8(2)
    • Vegans associated with lower bone mineral density, possibly linked to inadequate Vitamin D and calcium. Possibly linked to acidity and hormonal changes i.e. lower free testosterone, lower thyroid hormone production, lower intake of collagen peptides. Ambroszkiewicz J, et al. The Influence of vegan diet on bone mineral density and biochemical bone turnover markers. Pediatr Endocrinol Diabetes metab. 2016; 16(3):201-4
    • A vegan diet in men will mean less free testosterone. Lower free testosterone in vegans because of significantly elevated SHBG. This is handy for PCOS and acne especially considering that vegan diet also increases insulin sensitivity making a vegan diet a good strategy for PCOS as long as they use a low GI, high fat and fibre version of a vegan diet and not just high bread and cereal version. The lower androgen activity in vegans may make it harder to burn muscle and burn fat or get the gains in the gym that some athletes are chasing though. Key TJ, et al. Testosterone, sex hormone binding globulin, calculated free testosterone and oestradiol in male vegans and omnivores. Br J Nutr. 1990 Jul;64(1):111-9
    • Gut flora is different between groups but genetics and ancestry had greatest influence on gut flora changes in response to changing diets. Wu GD et al. Comparative metabolomics in vegans and omnivores reveal constraints on diet-dependant gut microbiota metabolite production. Gut. 2016 Jan; 65(1):63-72
    • Acid and Alkaline diet explained on the podcast. With initial theory of acid and alkaline foods being based on the pH of the ash of burnt food in a crucible determining its acidifying or alkalizing properties in the body is bad science and false and almost 60 years later people are still quoting from this research and ignoring more recent discoveries. How much acid is from our food? How much acidity is because of inadequate buffering minerals? How much of our acidity is controlled by the functional effects of foods for detoxification, elimination and efficient energy production? Did you know that most of the acidity in our body is metabolic waste created on a cellular level from poor energy production and inadequate oxygenation? Did you know that blood pH hardly changes or we die? We also discussed the extremes of pH necessary within the digestive tract for efficient digestion and absorption.
    • Also discussed Raw versus cooked foods and which is best for you.


Related Podcast – Listen here:

Episode 66 – Are Vegan Diets Better?