Researchers have found that losing weight and taking vitamin D supplements had a greater effect than weight loss alone in reducing the kind of chronic inflammation linked to some cancers.
The researchers – from the Fred Hutchinson Cancer Research Center and University of Washington Schools of Public Health and Medicine – compared weight loss and vitamin D supplementation with weight loss alone in a clinical trial involving 218 overweight or obese postmenopausal women. The women had low levels of vitamin D at the start of the study.
Losing weight can reduce inflammation, which is believed to be a pathway for some cancers. Vitamin D deficiency has also been linked to increased risk for certain cancers and to higher levels of several markers for inflammation, including the protein interleukin-6, or IL-6.
In this year-long study, researchers assigned women to the same weight-loss program. It involved dieting and 45 minutes or more of exercise at least five times a week. Half the women received a daily oral dose of vitamin D while the other half received a placebo.
Participants who lost at least 5 percent to 10 percent of their weight and took vitamin D significantly reduced their levels of IL-6. They experienced a 37 percent reduction compared to 17.2 percent for those in the group that went through weight loss alone. The results were published in the July issue of Cancer Prevention Research.