(HealthDay News) – Higher circulating levels of carotenoids correlate with a reduced risk of breast cancer, according to research published online Dec. 6 in the Journal of the National Cancer Institute.
A. Heather Eliassen, ScD, from Brigham & Women’s Hospital in Boston, and colleagues analyzed pooled data from eight cohort studies, comprising more than 80% of the world’s published prospective data on plasma or serum carotenoids and breast cancer. The analysis included 3,055 case subjects and 3,956 matched controls. Participant carotenoid levels were recalibrated to a common standard by reassaying 20 plasma or serum samples from each cohort together at the same laboratory.
The researchers found significant inverse associations between breast cancer and α-carotene (top vs. bottom quintile relative risk [RR], 0.87; Ptrend=0.04), β-carotene (RR, 0.83; Ptrend=0.02), lutein+zeaxanthin (RR, 0.84; Ptrend=0.05), lycopene (RR, 0.78; Ptrend=0.02), and total carotenoids (RR, 0.81; Ptrend=0.01). There was no significant association between β-cryptoxanthin and breast cancer risk. Stronger associations were found for several carotenoids and estrogen receptor negative (ER−) tumors than for ER+ tumors; for example, for the top versus the bottom quintile of β-carotene, the RR was 0.52 for ER− and 0.83 for ER+ tumors.
“This comprehensive prospective analysis suggests women with higher circulating levels of α-carotene, β-carotene, lutein+zeaxanthin, lycopene, and total carotenoids may be at reduced risk of breast cancer,” the authors write.
The study was partially funded by DSM Nutritional Products (formerly Roche Vitamins).