In previous studies, Cedric F Garland, professor in the Department of Family and Preventive Medicine at the University of California, San Diego, showed that low vitamin D levels were linked to a high risk of premenopausal breast cancer.

The findings, 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 establish its link with breast cancer survival rates.

ISLAMABAD- Breast cancer patients with high levels of vitamin D in their blood are twice as likely to survive the disease as women with low levels of this nutrient, scientists have found.

"Vitamin D metabolites increase communication between cells by switching on a protein that blocks aggressive cell division," said Garland. "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.”

Garland and colleagues 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.

"The study has implications for including vitamin D as an adjuvant to conventional breast cancer therapy," said co-author Heather Hofflich, UC San Diego Associate Professor in the Department of Medicine. The study is published in the journal Anticancer Research.