Study finds vitamin D boosts breast cancer survival
SAN DIEGO — According to recently released research, breast cancer patients were twice as likely to survive the disease if they had high levels of vitamin D in their blood.
University of California, San Diego School of Medicine researchers reported the findings in the March issue of Anticancer Research.
“Vitamin D metabolites increase communication between cells by switching on a protein that blocks aggressive cell division,” said Cedric F. Garland, professor in the department of family and preventive medicine. “As long as vitamin D receptors are present, tumor growth is prevented and kept from expanding its blood supply. Vitamin D receptors are not lost until a tumor is very advanced. This is the reason for better survival in patients whose vitamin D blood levels are high.”
In prior studies, Garland showed that low vitamin D levels were linked to a high risk of premenopausal breast cancer. That finding, he said, prompted him to question the relationship between 25-hydroxyvitamin D — a metabolite produced by the body from the ingestion of vitamin D — and breast cancer survival rates.
Garland and colleagues then performed a statistical analysis of five studies of 25-hydroxyvitamin D obtained at the time of patient diagnosis and their follow-up for an average of nine years. Combined, the studies included 4,443 breast cancer patients.
Women in the high serum group had an average level of 30 nanograms per milliliter (ng/ml) of 25-hydroxyvitamin D in their blood. The low group averaged 17 ng/ml. The average level in patients with breast cancer in the United States is 17 ng/ml, researchers said.