Vitamin D supplements could help prevent type 2 diabetes in those who possess a certain gene.
Figures show 4.6 million people in the UK have a diabetes diagnosis, but an estimated 6.3 million people have non-diabetic hyperglycemia, more commonly known as pre-diabetes, according to Diabetes UK.
If left untreated, pre-diabetes can develop into type 2 diabetes, yet vitamin D may help delay or prevent that progression.
Known as the sunshine vitamin, it’s found in the sun’s UVB rays, as well as oily fish, mushrooms and red meat and is vital for keeping bones, teeth and muscles healthy. But scientists say it also plays a role in blood sugar control.
A study by researchers at Tufts University in Massachusetts found pre-diabetic adults with certain variations in the vitamin D receptor gene had a 19 per cent lower risk of developing diabetes when taking a high daily dose of vitamin D.
If left untreated, pre-diabetes can progress into type 2 diabetes, but vitamin D could help, study finds (Getty/iStock)
“Diabetes has so many serious complications that develop slowly over years. If we can delay the time period that an individual will spend living with diabetes, we can stop some of those harmful side effects or lessen their severity,” said Bess Dawson-Hughes, senior scientist at Tufts University.
For the report, published in JAMA Network Open, researchers analysed data from the D2d study, a clinical trial which tested the effect of 4,000 units of vitamin D per day versus placebo in more than 2,000 US adults with pre-diabetes. They hoped to see if a daily high dose would lower the chance of these particularly high-risk individuals from developing diabetes.
Vitamin D circulating in the blood is converted into its active form in the body before binding to the vitamin D receptor, a protein that helps cells respond to the vitamin.
The researchers wondered whether genetic differences in this receptor might explain why some people benefited from vitamin D while others did not. The pancreas’s insulin-producing cells have vitamin D receptors, suggesting the vitamin may help influence insulin release and blood sugar control.
Researchers split participants into two groups: those who appeared to benefit from vitamin D supplementation and those who did not.
They found those with a gene variation, called AA, found in 30 per cent of the population, did not respond to daily treatment with a high dose of vitamin D. But the same treatment in adults with two other variations, AC and CC, saw a significantly reduced risk of developing diabetes.
“Part of what makes vitamin D appealing as a potential preventive tool is that it is inexpensive, widely available, and easy for people to take,” Professor Anastassios Pittas from Tufts University School of Medicine said.
However, study authors cautioned against taking high doses of vitamin D to prevent pre-diabetes without medical advice. The NHS urges people not to take more than 100 micrograms (4,000 IU) of vitamin D a day, as too much can cause calcium to build up in the body, weakening the bones, damaging the kidneys and the heart.