Japanese Study Confirms Vitamin D Reduces Cancer Risk
Vitamin D is an essential nutrient that is good for the health, and scientists continue to explore its other health benefits. In fact, a new study published in The British Medical Journal (BMJ) found that vitamin D reduces the risk of cancer.
The researchers conducted the study using data of 33,736 participants, aged between 40 and 69 years, from the Japan Public Health Center-based Prospective (JPHC) Study. A baseline survey provided detailed information on their medical history, diet, and lifestyle. Blood samples were also taken to measure baseline vitamin D levels.
The researchers divided the participants into four groups, depending on their levels of vitamin D. After that, they followed the participants for an average of 16 years, in which time they recorded more than 3,300 new cases of cancer. The study also included 4,044 randomly selected sub-cohort participants.
After cancer risk factors, such as age, weight, physical activity levels, smoking, alcohol consumption, and diet, were compensated for, the researchers found that participants with a higher level of vitamin D had a 20 to 25 percent lower risk for all cancers. For liver cancer, they showed an even bigger 30 to 55 percent lower risk of cancer, and the association was more evident in men than in women.
In addition, they found that vitamin D levels lower the risk for pre-menopausal breast cancer, but not for prostate and lung cancer.
Furthermore, they observed a ceiling effect for total cancer risk, meaning no further benefit would be obtained by further increases in vitamin D blood concentration. However, they failed to determine the optimal vitamin D concentration that reduced the risk of cancer. I’m suggesting therefore that 5,000 IU daily would seem about right.
“We observed that a higher circulating concentration of vitamin D was associated with a lower risk of subsequent cancer in a large Japanese population. Our findings support the hypothesis that vitamin D may confer protection against the risk of cancer,” said SanjeevBudhathoki, first author of the study.