Dear Editor,
Thank you for your comments on our article “Stroke and Diets: A Review.” Your points are well taken in that vegans are different from ovo-lactovegetarians because they consume no eggs or dairy products although both groups eat no meat, fish or poultry. In both EPIC-Oxford study [1] and our cohort [2] vegetarians and vegans were combined as one diet group in the statistical analyses, owing to the small number of vegans.
Our cohort [2] is different from other studies (including the EPIC-Oxford), our participants do not smoke, drink alcohol, besides being on Taiwanese diets which (both omnivores and vegetarian) are quite different from the typical Western diets in that they included more soy, rice, wheat, salt but less meat, milk products (cheese) [3]. In our study, both the study and control groups stay on similar diets except the study group omits meat due to religious reasons. This allows us to study the unique contribution of meat to the incidences of stroke. Even though our groups consume very little milk products, strict vegans by definition are rare, therefore we combined both in our study.
As mentioned in the discussion section of our study [2] there are controversies regarding the association between vegetarian diets and hemorrhagic strokes. We believe that other potential confounding factors such as phytochemicals, Vitamin B 12, homocysteine, and especially, alcohol intake should be considered. In the EPIC-Oxford study, nearly 80% of vegetarians in the EPIC-Oxford study drink varying degrees of alcohol but most participants in our studies avoid alcohol.
We agreed totally with your point that there are differences between vegan and ovo-lactovegetarians and further studies are necessary to demonstrate the health effects of eggs and milk products.
Financial support and sponsorship
Nil.
Conflicts of interest
Dr. Chin-Lon Lin, an editorial board member at Tzu Chi Medical Journal, had no role in the peer review process of or decision to publish this article.
REFERENCES
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