Omega-3, Few Differences Between Vegetarians and Vegans' Levels
Omega-3 Levels: Nearly Equal Between Vegetarians and Vegans
The levels of Omega-3 found in fish eaters, vegetarians, and vegans are similar. This was revealed by a study led by the University of East Anglia (Norwich, UK), where Alisa Welch and colleagues investigated whether excluding fish from the diet reduces the presence of these valuable molecules in the body. The research results were published in the American Journal of Clinical Nutrition.
Sources of Omega-3
Omega-3 fatty acids are present in various animal and plant-based foods, but their main source is fatty fish. Fish contain high levels of both EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), the Omega-3s active in the human body. Plant-based foods (such as walnuts and flaxseeds) are instead better sources of ALA (alpha-linolenic acid), a precursor of EPA and DHA. Once ingested, the body must convert ALA into these two fatty acids to benefit from Omega-3 effects. For this reason, Welch and colleagues analyzed whether eliminating fish from the diet (as vegetarians and vegans do) reduces EPA and DHA levels in the body.
The Study
The research involved 14,422 individuals from the EPIC (European Prospective Investigation into Cancer and Nutrition)-Norfolk study. The authors analyzed dietary habits recorded through weekly diaries to assess any correlation between diet type and Omega-3 levels in the bloodstream. Plasma concentrations of EPA and DHA were measured. This information also allowed the calculation of the conversion rate of ALA into EPA and DHA.
Results
The analyses showed that for those who do not eat fish but include other animal foods, the main source of Omega-3 is meat. Vegetarians obtain these nutrients from spreadable fats (e.g., butter or margarine), soups, and sauces. The total amount of Omega-3 consumed by fish-free eaters ranged between 57% and 80% of the intake typical of fish consumers. However, differences in plasma concentrations were much smaller. Moreover, the conversion rate of ALA to EPA and DHA was higher in fish-free eaters and in women.
An Unexpected Conversion Rate
Based on these results, the researchers concluded that diet type does not strongly influence the Omega-3 levels in the body. They hypothesize that this is possible because fish-free eaters have a higher conversion rate of ALA to EPA and DHA than those who eat fish.
