Thursday
Sep132012

VITAMIN D: more than a vitamin & more than just bone health

Lack of vitamin D is the most common nutritional deficiency in the world. Three out of every four Americans are deficient in vitamin D, up from one out of two twenty years ago. Normally we think of a vitamin as a substance that we must get from our diet, because we are unable to synthesize it ourselves. These substances participate in biological conditions that allow the body to operate optimally. But despite its name, vitamin D isn't really a vitamin. It is in a class of its own, and acts more like a hormone. Like other hormones, it has far reaching effects that influence metabolic pathways, cellular functions, and the expression of many genes. The metabolically active form of vitamin D targets more than two thousand genes. We formerly believed that vitamin D receptors were only in bones, intestines and kidneys. We now know that vitamin D receptors are everywhere in the body. There is even proof that vitamin D receptors exist in the brain and are responsible for the production of mood-elevating serotonin. This explains how it may reduce depression.

Vitamin D in its inactive form is a cholesterol derivative located in our skin. Exposure by the sun's UVB light converts inactive vitamin D to its active form. But a recent 2012 statement from the American Academy of Dermatology does not recommend getting vitamin D by natural (sun exposure) or indoor tanning (artificial), because of the risk of skin cancers and premature aging of the skin. This statement, however, is not universally accepted by the medical community. Many physicians speak of "safe sun exposure" and vitamin D production .Experts say that  going outside wearing shorts and a tank top in midday sun and without sunscreen may give a fair skinned individual  enough radiation to produce nearly 10, 000 international units of the vitamin. Darker skinned individuals typically require more sun exposure. But practicing this 365 days of the year in northern climates is essentially impossible .Very little vitamin D can be obtained from the diet in the form of fortified foods. The amount of vitamin D found in multivitamins is grossly inadequate. Therefore, the only practical solution is to ingest the vitamin in the form of a daily supplement.

Research published this year in the Archives of Internal Medicine shows that those with the lowest vitamin D levels have more than double the risk of dying from heart disease and other causes over an eight year period compared with those with the highest vitamin D levels. Other studies have demonstrated an increased risk of heart attacks in those with low vitamin D levels.   

Other health benefits of vitamin D include the following:

* BONE HEALTH: can help prevent osteopenia, osteoporosis, rickets and fractures through calcium and phosphorous absorption.

* CELLULAR HEALTH: can help prevent certain cancers (e.g. prostate, pancreatic, breast, ovarian and colon); prevents infectious diseases, and upper-respiratory-tract infections

* ORGAN HEALTH: can help prevent heart disease and stroke, may help prevent type 2 diabetes, periodontitis and tooth loss, and other inflammatory conditions.

* MUSCULAR HEALTH: supports muscular strength

* AUTOIMMUNE HEALTH : May help mitigate the effects of multiple sclerosis, type 1 diabetes mellitus, Crohn's disease, and rheumatoid arthritis.

* BRAIN HEALTH: may play a role in preventing depression, Alzheimer's disease, and dementia.

* MOOD-RELATED HEALTH: Helps prevent seasonal affective disorder, premenstrual syndrome (PMS) and sleeping disorders.

An interesting fact is that despite vitamin D being a fat soluble vitamin, whereby excess vitamin is stored in fat cells, the obese population tends to be especially deficient in this vitamin. Why? The vitamin D gets locked inside the fat cells, unavailable for use. Moreover, obese individuals are frequently deficient in vitamin D to start with because they go outside much less. So it is not surprising that obese patients need two to three times more vitamin D than those of normal weight.

Breast cancer is the deadliest killer of woman after heart disease, and more than forty thousand women die from the disease annually. Here is a staggering statistic: Women who are deficient in vitamin D at the time they were diagnosed with breast cancer are nearly 75% more likely to die of the disease than women with sufficient vitamin D levels. In May 1999, a landmark study by Dr. Esther John based on the analysis of breast cancer statistics from the National Health and Nutrition Examination Survey published its results: Sun exposure and a vitamin D rich diet significantly lowered the risk of breast cancer.

There is also impressive data regarding the role of vitamin D in preventing death from both prostate and colon cancer.

With so many far reaching preventative effects of vitamin D, you really need to know your actual level. Indeed, the only way to know for sure the extent of your deficiency is to ask for a 25-hydroxyvitamin D test. This is the circulating form of vitamin D that the liver generates which then becomes activated by the kidneys. Keep in mind, a normal level of the active form does not mean that you have adequate levels, so be sure to request the 25(OH)D test. This gives the most accurate assessment of your vitamin D status.

What constitutes optimal levels? I concur with the recommendation given by Dr. Michael Holick, world-renowned expert on vitamin D, and author of VITAMIN D SOLUTION:  25-hydroxyvitamin D blood levels should optimally be at 50 ng/ml. and above.

Vitamin D can be found in 2 forms. Vitamin D2 is manufactured by plants or fungus, and is obtained by ingesting fortified foods, such as juices, milk or cereal. Vitamin D3 is what the body synthesizes in the skin from contact by sunlight. It can also be obtained by consuming animal products. It is the preferred form taken as a dietary supplement.

Remember>>> vitamin D is not merely a vitamin. It acts more like a hormone. Essentially all diseases of aging have one factor in common—INFLAMMATION. This includes heart disease, cancer, autoimmune disorders and Alzheimer's. Vitamin D plays an important role in preventing or mitigating this inflammation. It behooves all of us to take the driver's seat when it comes to our health and ensure that we have adequate levels of this critically important vitamin. This is the key in becoming your own medical advocate. After all, whose body is it? It's your body! It's your responsibility to strive for an optimal state of wellness. Don't give it up!

Dr. Elkin is a board-certified internist, cardiologist and anti-aging medical specialist.

VERY IMPORTANT NOTE / DISCLAIMER: I am offering—always—only general information and my own opinion on this blog. Always contact your physician or a health professional before starting any treatments, exercise programs or using supplements. ©Howard Elkin MD FACC, 2012

PrintView Printer Friendly Version

EmailEmail Article to Friend

Please click to continue