Vitamin D can reduce risk for diabetes and may even add years to your life, new research suggests. But most people aren’t getting enough of this inexpensive nutrient, which costs as little as 7 cents a pill and is produced naturally when we’re out in the sun.
Vitamin D deficiency can actually be fatal, according to a new analysis published in American Journal of Public Health. The researchers found that people with low levels of 25-hydroxyvitamin D (the main form of vitamin D found in blood) were twice as likely to die prematurely than those with higher levels.
Two of out three Americans have potentially “hazardous” vitamin D deficiency
“Three years ago, the Institute of Medicine (IOM) concluded that having a too-low blood level of vitamin D was hazardous,” lead study author Cedric Garland, DrPh, professor in the department of Family and Preventive Medicine at UC San Diego reported in a statement.
The IOM study only looked at risk for bone disease, while the new analysis is the first to link low levels to risk for premature death from all causes. And while the IOM found that the danger zone was a blood vitamin D level of 20 nanograms per milliliter (ng/ml), the analysis found that about half of the participants at risk for early death had a vitamin D blood level of 30 ng/ml.
That’s alarming, since two-thirds of the US population has an estimated level below 30 ng/ml, according to Dr. Garland.
“This study should give the medical community and public substantial reassurance that vitamin D is safe when used in appropriate doses up to 4,000 International Units (IU) per day,” remarked Heather Hofflich, DO, professor in the UC San Diego School of Medicine’s Department of Medicine.
Dr. Hofflich cautions, however, that patients should consult their medical provider before changing their intake of vitamin D and also advises having blood levels of 25-hydroxyvitamin D checked annually.
The analysis pooled data from 32 studies that included 566,583 people from 14 countries. The participants’ average age when their blood was drawn was 55 and they were followed for an average of nine years.
The sunshine vitamin could be inexpensive weapon against diabetes
Another new study, presented in abstract form at the American Diabetes Annual Meeting in San Francisco, reports that vitamin D supplements dramatically improve insulin sensitivity in obese people with insulin resistance, the disorder that leads to type 2 diabetes.
Specifically, during the randomized, double-blinded study, patients with low levels of the sunshine vitamin exhibited a 34 percent improvement in sensitivity to their own insulin after treatment with supplements, reports study author Meredith Hawkins, MD, professor of medicine at Einstein and attending physician, endocrinology at Montefiore Medical Center.
Supplementation also significantly reduced fibrosis (stiffening and scarring) in the patients’ adipose (fatty) tissue. Adipose tissue fibrosis is believed to contribute to both insulin resistance and inflammation in obese people, adds researcher Akankasha Goyal, another of the study authors and a research fellow in Dr. Hawkins’ lab.
In other words, explains Dr. Hawkins, the patients’ fatty tissue becomes metabolically more normal, suggesting that in people who are migrating towards type 2 diabetes—but don’t yet have the full-blown disease—vitamin D may be an inexpensive weapon to diabetes risk.
However, the study found that vitamin D is only beneficial for people with deficiency. During the 8-week study, patients either received once-a-week oral doses of vitamin D3 oil or a placebo oil.