Higher levels of vitamin D in the blood are associated with a lower risk of getting colon cancer. This is according to a study published by the Journal of the National Cancer Institute. Another study concludes that high doses of vitamin D can slow the growth of colon cancer.

The international group of researchers combined data from 17 prospective studies, a type of study that people follow over time to try to find out why some of them get colon cancer. The analysis is the largest so far, with data from around 12,800 people. All participants were tested for vitamin D levels in their blood prior to diagnosis.

31% higher risk of colon cancer due to vitamin D deficiency

The study found that people with a vitamin D deficiency, according to the National Academy of Medicine (NAM) definition, had a 31% higher risk of colorectal cancer during the time they were followed. This was on average five and a half years (the full range was 1-25 years). The lowest risk of colorectal cancer was found in people who had a circulating vitamin D level that was even higher than the NAM recommendation for sufficient concentrations.

According to Marji McCullough, ScD, RD, American Cancer Society epidemiologist and co-author of the study, the findings indicate that there may be a target range of circulating vitamin D levels that may be associated with the lowest risk of colon cancer. Marji McCullough: “What is optimal for colorectal cancer can differ for what is optimal for bone health.” However, these findings do not change current public health policy. “This major study can contribute to the evidence being reviewed by scientific committees that establish recommendations for nutrients,” said McCullough.

Vitamin D can delay colon cancer progression

A new study concludes that high doses of vitamin D can significantly slow the progression of colon cancer. In the study, the researchers recruited 139 people with previously untreated metastatic colon cancer and split them into two groups: high-dose vitamin D and low-dose vitamin D. The high-dose group took 8,000 IU of vitamin D every day for 14 days, before transferring switch to 4000 IU per day. The low-dose group took 400 IU per day during the study. Both groups also received standard chemotherapy during the trial. “The results of our study suggest an improved outcome for patients receiving vitamin D supplementation, and we look forward to starting a larger study to confirm these exciting and provocative findings,” Dr. Charles Fuchs, senior study author and director of the Yale Cancer Center in New Haven, Connecticut.

Vitamin D and magnesium

Do you want to increase your vitamin D level? Make sure there is enough magnesium in the body, because vitamin D and magnesium work together. Vitamin D cannot be converted without sufficient magnesium.

Source: Journal of the National Cancer Institute, Medical News Today, JAMA network