Adults with increased blood concentrations of antioxidants, such as beta-carotene, lutein and zeaxanthin are less likely to have depression, a new US study suggests.
To examine a potential relationship between elevated symptoms of depression and antioxidant status, serum concentrations of carotenoids and the vitamins A, C and E as well as symptoms of depression were mea-sured in 1798 US participants (age 20–85) from the National Health and Nutrition Examination Surveys 2005-6 (1). The study results showed that a higher total serum carotenoid level was associated with a significantly lower likelihood of elevated depressive symptoms, each increase in exposure leading to an overall reduction of 37 % in the odds. A dose-response relationship was observed only for total serum carotenoids. Among carotenoids, increased levels of beta-carotene (men and women combined) and lutein plus zeaxanthins (women only) showed an independent association with reduced depressive symptoms.
The researchers commented that these findings warrant further investigation as antioxidants may help to reduce oxidative damage in the brain. Evidence from epidemiological studies has triggered the hypothesis that depression may be the outcome of low serum antioxidant status and that increased intake of antioxi-dants in the diet could reduce oxidative stress, thereby reducing the incidence of elevated depressive symptoms by reducing lipid peroxidation in the brain (2).