Yes, vitamin D has made the news once again.
According to a study published online in JAMA Oncology, women with higher vitamin D levels in their blood following a breast cancer diagnosis had significantly better survival rates.
While vitamin D—which is also referred to as the “sunshine vitamin”—is mostly known for its role in the proper development of bones and teeth, a vitamin D deficiency has been linked to an increased risk of various cancers, as well as chronic conditions such as asthma.
Over a seven-year period, researchers from Kaiser Permanente and Roswell Park Cancer Institute analyzed blood samples of 1,666 women who had been diagnosed with invasive breast cancer in 2006 (the year the study began). The samples were provided within two months of their diagnosis. The participants also answered questions about their diets and lifestyles, as well as other risk factors (i.e., race, obesity, age).
Investigators followed up with these women five times throughout the study period. They learned that in addition to lower overall mortality among all breast cancer survivors studied, there were even stronger positive associations among premenopausal women in the highest third of vitamin D levels for breast-cancer-specific (63 percent better) and recurrence-free (48 percent better) participants during a median follow-up of seven years.
“I think these findings are intriguing, and I agree that it’s consistent with what we’ve learned about vitamin D over the last few years — that it does seem to have a role in maintaining the immune system,” said Dennis R. Holmes, MD, breast cancer surgeon and researcher and interim director of the Margie Petersen Breast Center at the John Wayne Cancer Institute at Providence Saint John’s Health Center in Santa Monica, Calif. “We haven’t had strong data to indicate that there was a link to breast cancer — one that was compelling, at least — but this finding is certainly compelling,” he told Yahoo Beauty.
The scientists in this latest study did not examine the effects of vitamin D consumption from food versus supplements. However, their research supports recommended daily levels of vitamin D — 600 IU for those 1 to 70 years old and pregnant or breastfeeding women, and 800 IU for those over 71 years old.
But there is conflicting information from the medical community regarding the proper daily dosage for this nutrient. In fact, just this week, experts wrote in the New England Journal of Medicine that misunderstandings about the recommended amount of vitamin D have led to misinterpretation of blood tests and many people thinking they need more than they really do.
Holmes believes that most people, especially those who are health-conscious, are not receiving enough of the vitamin. “The normal healthy lifestyle we pursue tends to include eating less dairy products [fortified milk is a common source],” he explains. Other common practiced healthy behaviors include swapping soy milk for regular milk, as well as wearing sunscreen, “and those things are undermining the effort to increase vitamin D and maintain normal vitamin D levels.”
He advises speaking with your doctor about whether or not a blood test (25-Hydroxyvitamin D, or the 25OHD) should be performed. “And if the physician encourages it — which I think many will — to supplement appropriately.”