Association of abdominal obesity with decreased serum levels of carotenoids in a healthy Japanese population

Background & aims: Few epidemiological studies have investigated the relationship between abdominal adiposity and serum levels of carotenoids. This study investigated the relationship between total and abdominal obesity and serum levels of carotenoids. Methods: Study population consisted of healthy Japanese males (n = 192) and females (n = 398) who attended a health examination screening (age: 49-86 years). Serum carotenoids were measured by high-performance liquid chromatography. Multiple logistic regression analysis was used to provide the multivariate-adjusted odds ratio (OR) and 95% confidence interval (CI) of obesity indices for low levels of serum carotenoids. Results: In females, High waist circumference was associated with low levels of serum canthaxanthin (OR=2.00, 95% CI=1.26-3.19) and beta-carotene (BC) (OR=2.01, 95% CI=1.23-3.28). High waist hip ratio was also associated with low levels of serum alpha- carotene and BC (OR=2.44, 95% CI=1.49-4.03, and OR =1.97, 95% CI=1.20-3.28, respectively). Similar results were obtained when body mass index was added to confounding factors. In males, however, there were no significant associations between obesity indices and serum levels of carotenoids. Conclusions: Our results suggest that abdominal fat accumulation is associated with oxidative stress as determined by low levels of serum carotenoids in females. In males, further study excluding the effect of strong confounding factors, including smoking, is needed.