Low levels of vitamin D don't put
older women at greater risk for type 2
diabetes, a large study of
The findings may further temper the enthusiasm for vitamin D that built up in recent years, as studies linked it to lower risks of everything from , to severe asthma, heart disease, certain cancers and depression.
The problem with those studies is that they were observational, which means that researchers simply looked at people's vitamin D intake, or their blood levels of the vitamin, and whether or not they developed a given health condition.
Those types of studies cannot
prove that vitamin D was the reason for any lower disease risk.
"You can't make dietary recommendations based on observational studies," said Dr. Jennifer G. Robinson, a professor of epidemiology and medicine at the
In an interview, she pointed to
the recent report on vitamin D from the Institute
of Medicine (IOM), an independent scientific body that advises the
It also said average Americans already have vitamin D blood levels at or above the amount that's needed for good bone health. (Read the entire article)
Drinking yogurt with extra vitamin D may help people with diabetes regulate their blood sugar, a study from Iran finds.
In the trial, 90 adults with diabetes were divided into three groups, all given daily yogurt drinks: one group received plain yogurt, one got yogurt with extra vitamin D, and one was given yogurt with extra vitamin D and calcium.
At the end of 12 weeks, "we found a relatively remarkable improvement" in blood sugar levels in the groups that got extra vitamin D, compared to the plain yogurt group, co-author Tirang Neyestani, associate professor at National Nutrition and Food Technology Research Institute in Iran, told Reuters Health in an e-mail.
Past studies on the role of vitamin D in diabetes have not been able to show cause and effect.
It's noteworthy that this study
does, and that it suggests vitamin D has a positive effect on people with type
2 diabetes, said Dr. Anastassios Pittas, assistant professor of medicine at
Tufts University School of Medicine in