Study Finds Vitamin D Deficiency Common in People With Diabetes

Vitamin D deficiency, long suspected to be a risk factor for diabetes and glucose intolerance, is commonly found in people with poor diabetes control, according to a new study.

''Our study could not show cause and effect," says Esther Krug, MD, an endocrinologist at Sinai Hospital of Baltimore and assistant professor of medicine at Johns Hopkins University School of Medicine, Baltimore, who presented the findings at ENDO 2010, the annual meeting of The Endocrine Society, in San Diego.

But she did find that vitamin D deficiency was common in her study, with more than 91% of participants deficient. As the deficiency worsened, so did diabetes control. Only eight of the 124 participants took vitamin D supplements, she found.

About 18 million people in the U.S. have been diagnosed with diabetes, according to the American Diabetes Association, and about 6 million more are believed to have the condition but are undiagnosed.

If you have diabetes – are at risk for diabetes – and/or want to lose weight, you owe it to yourself to read this whole article and click on the banner below for important information that can really help you.

Vitamin D Deficiency and Diabetes Risk

"People at risk for diabetes should be screened for low vitamin D levels," said Mary Ann Emanuele, M.D., F.A.C.P., study co-author and professor of medicine, division of endocrinology and metabolism, Loyola University Health System. "This will allow health care professionals to identify a nutrient deficiency early on and intervene to improve the long term health of these individuals."

Vitamin D deficiency also may be associated with hyperglycemia, insulin resistance, hypertension and heart disease. In fact, Penckofer recently published another study in Circulation that reported on the role of chronic vitamin D deficiency in heart disease. The Circulation study authors included Glen W. Sizemore, MD, emeritus professor of Medicine, Division of Endocrinology and Metabolism, Loyola University Chicago Stritch School of Medicine, and Diane E. Wallis, MD, Midwest Heart Specialists, Downers Grove, Ill.

Do Vitamin D Supplements Help?

Many of the 23 million Americans with diabetes have low vitamin D levels. Evidence suggests that vitamin D plays an integral role in insulin sensitivity and secretion. Vitamin D deficiency results in part from poor nutrition, which is one of the most challenging issues for people with diabetes. Another culprit is reduced exposure to sunlight, which is common during cold weather months when days are shorter and more time is spent indoors.

A recent review article published by researchers from Loyola University Chicago Marcella Niehoff School of Nursing concluded that adequate intake of vitamin D may prevent or delay the onset of diabetes and reduce complications for those who have already been diagnosed. These findings appeared in the latest issue of Diabetes Educator.

One study examined for this review article evaluated 3,000 people with type 1 diabetes and found a decreased risk in disease for people who took vitamin D supplements. Observational studies of people with type 2 diabetes also revealed that supplementation may be important in the prevention of this disease, provided that a dosage of 5,000 IU or more is taken.

"Management of vitamin D deficiency may be a simple and cost-effective method to improve blood sugar control and prevent the serious complications associated with diabetes," said Joanne Kouba, Ph.D., R.D., L.D.N., study co-author and clinical assistant professor of dietetics, Loyola University Chicago Marcella Niehoff School of Nursing.

Diet alone may not be sufficient to manage vitamin D levels. A combination of adequate dietary intake of vitamin D, exposure to sunlight, and treatment with vitamin D2 or D3 supplements can decrease the risk of diabetes and related health concerns. The preferred range in the body is 30 - 60 ng/mL of 25(OH) vitamin D.

Low Vitamin D, Poor Diabetes Control: The Study

Krug and her colleagues decided to look at vitamin D deficiency in the wake of reports suggesting that vitamin D has an active role in regulating pancreatic beta cells, which make insulin.

So they evaluated the medical charts of 124 people with type 2 diabetes (in which the body doesn't make enough insulin or the cells ignore the insulin) seen at an outpatient clinic from 2003 to 2008. The charts contained information on the patients' age, race, vitamin D levels, calcium intake, family history of diabetes, and results of their hemoglobin A1c blood test. The A1c provides an average measurement of blood sugar control over about a 12-week span. (For people with diabetes, the goal is 7%; for people without, the normal range is 4%-6%.).

Krug's team divided the vitamin D levels they found into four groups: normal (defined in the study as above 32 nanograms per deciliter), mild deficiency, moderate deficiency, or severe.

In all, 113 of the 124 patients (91.1%) were vitamin D deficient -- 35.5% severely, 38.7% moderately, and 16.9% mildly.

The average A1c was higher in patients with severe vitamin D deficiency compared to those with normal levels of vitamin D. Those with severe deficiency had an average of 8.1%; those with normal vitamin D levels averaged 7.1%.

Krug found racial differences. ''In people of color, vitamin D levels were even lower than in Caucasians and they were associated with even poorer diabetes control," she tells WebMD.

Only 6.4% were on vitamin D supplementation. This was true, Krug says, even though they had medical coverage and saw their doctors. She suspects a lack of awareness on the part of the physicians partly explains the frequent deficiencies she found.

Aggressive screening of vitamin D levels is crucial for people with diabetes, Krug says. Once a supplement is recommended, she says, the blood levels should be rechecked to see if the supplement sufficiently increases vitamin D levels.

Other Studies Confirm These Findings

Meanwhile, over in Holland, another study also found a link between vitamin D and diabetes, plus, it confirmed that vitamin D may play a role in developing metabolic syndrome. In that study, which followed 1300 subjects, all over the age of 65, about half had vitamin D deficiency, a percentage that still exceeds that found in the general population. Plus, 37 percent had metabolic syndrome, meaning that they had hypertension, high cholesterol, high blood sugar levels, and abdominal obesity — a constellation of factors considered precursors to both heart problems and diabetes.

I’ve written before about the profound health implications of vitamin D deficiency — beyond diabetes and skeletal problems. As I’ve said, vitamin D deficiency has been implicated in the development of various cancers, cardiovascular disease, psoriasis, Lupus, multiple sclerosis, osteoporosis, arthritis, lupus, and liver, and kidney disease.

Take Vitamin D Supplements

If you clicked on the banner above – you would have learned that the real culprit with diabetes – is not with the diabetes itself – but the health complications it causes, and one of the best way to proect against these consequences is to make sure your vitamin D levels are at optimum levels.

The moral of all this research seems fairly obvious. Get enough vitamin D. It can’t hurt to supplement with 5,000 IU of vitamin D3 daily (taken with your largest meal), and it may even pay to have your blood levels of vitamin D tested, even if you assume you’re fine because you frolic in the sun every day.

In fact, a study of vitamin D levels in Hawaii in 2007 found that 51 percent of the 93 subjects were vitamin D deficient, even though these subjects had abundant exposure to sunlight year-round. The study authors wrote, "These data suggest that variable responsiveness to UVB radiation is evident among individuals, causing some to have low vitamin D status despite abundant sun exposure." Or perhaps, they were just using too much sunscreen.

IMPORTANT Supplementing with Vitamin D, even in intravenous megadoses does NOT improve blood sugar or insulin resistance in any significant way. If you want to cure your diabetes then look into the work of this New Mexican Doctor and his amazing record of success

I recommend Vitamin D3 and Vitamin D3 drops from Primal Force.

If you want to know why – just look to the Nav Bar on the left and start reading the many articles I've published about the benefits of Vitamin D, what to take, and how much to realize these benefits.

Vitamin D Does Not Cure diabetes

Insulin resistance (or insensitivity) occurs when the body's tissues stop responding as strongly to the presence of insulin. As a consequence, the cells uptake less sugar from the bloodstream, producing the elevated glucose levels characteristic of diabetes.

In another study, conducted by researchers from Massey University and published in the British Journal of Nutrition, researchers randomly assigned 81 South Asian women between the ages of 23 and 68 to take either a placebo or 4,000 IU of vitamin D once per day. All participants suffered from insulin sensitivity at the start of the study, but none were taking diabetes drugs or vitamin D supplements larger than 1,000 IU per day.

At the start of the study, the average participant had vitamin D blood levels of approximately 50 nanomoles per liter, slightly lower than the average levels in a U.S. adult (60-75 nmol/L). After six months, women in the vitamin D group exhibited significantly more insulin sensitivity and less insulin resistance than women who had received a placebo. The largest effect was seen in women whose vitamin D blood levels had reached 80 to 119 nmol/L.

According to the Vitamin D Council, blood levels should be at least 125 nmol/L for optimal health.

Second Opinion

The new study lends support to a growing body of scientific and clinical data linking vitamin D with insulin and glucose, says Ruchi Mathur, MD, an endocrinologist and assistant professor of medicine at Cedars-Sinai Medical Center, Los Angeles, who reviewed the study for WebMD.

Other research has shown that supplementing with vitamin D and calcium slows the progression to type 2 diabetes, Mathur says.

Even so, she tells WebMD, "At present, a direct link between vitamin D and type 2 diabetes is not conclusively established."

Guess what? Medical researchers want to do more research. You can either do nothing … or … decide to change your diet (using the 30 day cure for Diabetes information we recommend.

No matter what you decide – taking vitamin D supplements will help you with your overall health and improve your chances for a successful outcome.


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