Vitamin supplement may delay diabetes in select groups, researchers say

High-dose vitamin D supplements could help reduce diabetes risk among certain groups, according to new research from Tufts University.

In a large clinical trial, researchers performed genetic testing of more than 2,000 U.S. adults with prediabetes after they received 4,000 units per day of vitamin D supplements, then compared them to a placebo group.

An earlier study showed no significant reduction in diabetes risk in the group receiving vitamin D supplementation, but when the researchers looked closer, they found a benefit for certain genetic groups.

For the new study, the Tufts researchers compared participants who appeared to benefit from vitamin D supplementation to those who did not, then examined how outcomes differed across three common variants of the vitamin D receptor gene.

DEMENTIA RISK COULD DIP WITH COMMON VACCINE, STUDY SUGGESTS

People who had certain versions of a vitamin D-related gene (called AC or CC) were 19% less likely to get diabetes when they took vitamin D compared to people who took a placebo, according to a university press release.

Participants with another genetic variant (AA) showed no benefit from supplementation.

Vitamin D seems to work by attaching to a specific "receiver" in the body called the vitamin D receptor, the researchers discovered. These receptors are found in many places, including the pancreas, the organ that makes insulin.

The findings were published last week in JAMA Network Open.

DIABETES PREVENTION LINKED TO SPECIFIC TYPE OF EXERCISE, STUDY SHOWS

"Our finding is an example of the emerging science of precision nutrition or precision medicine, in which an intervention can be tailored to the needs of individuals according to their genetic makeup and disease risk," Bess Dawson-Hughes, the study’s lead author and a senior scientist at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, told Fox News Digital.

"Taking a vitamin D supplement daily is an easy, inexpensive and generally safe approach to reducing diabetes risk," she added. "In principle, this could involve a single, relatively inexpensive genetic test."

There were some limitations to the study, the researchers noted, including that this was a secondary analysis rather than a primary randomized comparison.

"Like any other first observation, this finding needs to be replicated in a future study," the researcher said.

CLICK HERE FOR MORE HEALTH STORIES

The study only included individuals with prediabetes, which could limit relevance to broader populations. The results seen in specific genetic groups need to be confirmed in more studies before doctors can use them in patient care.

The authors emphasized that people should not start taking high doses of vitamin D as a diabetes prevention strategy based on this study.

"It is too early to make specific recommendations for the general population," Dawson-Hughes said. 

CLICK HERE TO SIGN UP FOR OUR HEALTH NEWSLETTER

Current recommendations suggest that most adults get about 600 IU of vitamin D daily (ages 1–70) and 800 IU for those over 70. However, previous studies have shown that taking very high doses can be harmful for older adults.

"There is some evidence, from my laboratory and others, that the relatively high blood levels of 25-hydroxyvitamin D needed to achieve the diabetes risk reduction have been associated with an increased risk of falling in older adults," Dawson-Hughes noted.  

"I would not advise older adults to take a daily dose of 4,000 IU of vitamin D without first consulting with their doctors."

This new study raises another question, according to Dawson-Hughes: Would vitamin D supplementation in adults with the responsive genotypes lower the risk of developing prediabetes, the forerunner to Type 2 diabetes? 

TEST YOURSELF WITH OUR LATEST LIFESTYLE QUIZ

"This is important because prediabetes is not a benign condition," she said. "Adults with prediabetes also have an increased risk of cardiovascular disease."