Beta-carotene may reduce breast cancer risk in women

Increased dietary intakes of alpha- and beta-carotene may reduce the risk of breast cancer among female smokers, a news study suggests.

The study, which followed 36,664 women for almost a decade, reports that increased dietary intakes of alpha- and beta-carotene was associated with a 60 percent reduction in hormone-sensitive breast cancer in female smokers (1). No link between dietary carotenoids and overal breast cancer risk was shown.

The results suggest female smokers could benefit from increasing their intakes of carotenoid-rich foods, particularly those rich in alpha- and beta-carotene. The potential protective effect of alpha-carotene and beta-carotene against breast cancer may be mediated through their antioxidant properties, the researchers commented. A protective effect of carotenoids may also be more pronounced among smokers because tobacco smoke induces oxidative stress.

The role of carotenoids, and beta-carotene in particular, in cancer is controversial, with some studies reporting that the intake of very high doses of beta-carotene supplements over years may increase the risk of lung cancer in heavy smokers.

Hormone-sensitive tumors are stimulated to grow by the female hormones estrogen and progesterone. Over one million women worldwide are diagnosed with breast cancer every year, with the highest incidences in the US and the Netherlands. China has the lowest incidence and mortality rate of the disease.

1. Larsson S. C. et al. Dietary carotenoids and risk of hormone receptor-defined breast cancer in a prospective cohort of Swedish women. European Journal of Cancer. February 2010.