Higher betaine intake tended to be associated (only a trend p=0.08) with a decreased risk of coronary heart disease mortality in Japanese men after controlling for covariates.

Background: Dietary intakes of betaine and choline may reduce the risk of cardiovascular disease; however, epidemiologic evidence is limited. Seafood is a rich source of betaine and is a popular traditional food in Japan.Objective: We examined the associations of betaine and choline intakes with cardiovascular disease mortality in a population-based cohort study in Japan.
Methods: Study subjects were 13,355 male and 15,724 female residents of Takayama City, Japan, who were aged ≥35 y and enrolled in 1992. Their diets were assessed by a validated food frequency questionnaire. Deaths from coronary heart disease and stroke were identified from death certificates over 16 y.
Results: During follow-up, we documented 308 deaths from coronary heart disease and 676 deaths from stroke (393 from ischemic and 153 from hemorrhagic strokes). Compared with the lowest quartile, the second, third, and highest quartiles of betaine intake were significantly associated with a decreased risk of mortality from coronary heart disease in men after controlling for covariates. The HRs were 0.58 (95% CI: 0.36, 0.93), 0.62 (95% CI: 0.39, 0.998), and 0.60 (95% CI: 0.37, 0.97), respectively. The trend was not statistically significant (P = 0.08). There was no significant association between betaine intake and the risk of mortality from ischemic stroke. In women, betaine intake was unrelated to mortality from coronary heart disease and stroke (P = 0.32 and 0.73, respectively, for interaction by sex). There was no significant association between choline intake and cardiovascular disease mortality in men or women.
Conclusion: Overall, we found no clear evidence of significant associations between choline and betaine intakes and cardiovascular disease mortality in Japanese men and women.

Nagata, C., et al., Choline and Betaine Intakes Are Not Associated with Cardiovascular Disease Mortality in Japanese Men and Women. The Journal of Nutrition, 2015.