There is a vast body of science showing the many health benefits of Vitamin D. You may be surprised to learn the important role that vitamin D plays in your overall health.
Special report:
Pediatricians group doubles recommended vitamin D dose for children:
New guidelines from the American Academy of Pediatrics call for 400 international units a day, beginning in the first few days of life, for lasting health benefits.
The American Academy of Pediatrics has doubled its recommendation for children’s daily dose of vitamin D in the hopes of preventing rickets and reaping other health benefits.
“We are doubling the recommended amount of vitamin D children need each day because evidence has shown this could have lifelong health benefits,” said Dr. Frank Greer of the American Academy of Pediatrics, which released the new recommendations at a meeting in Boston.
The new guidelines from the nation’s leading group of pediatricians call for children to receive 400 international units of vitamin D per day, beginning in the first few days of life.
Children who do not get enough vitamin D are at risk for rickets, a bone-softening disease that results in stunted growth and skeletal deformities if not corrected while the child is young. Babies who are exclusively breast-fed are at particular risk because nursing mothers tend to be deficient in vitamin D also.
Essential Nutrient, - Why vitamin D deficiency may be a hidden epidemic:
What exactly are the health benefits of vitamin D? How much does a person need? And why is the issue so often framed in terms of sun exposure—can’t you just drink fortified milk or take a multivitamin?
Let’s start with the basics: Vitamin D is a fat-soluble substance (that is, it dissolves in and can be stored by fat deposits in the body). It is present in salmon, mackerel, sardines, and cod liver oil; fortified foods including milk, breakfast cereals, and some juices; and vitamin supplements. It can also be synthesized in the skin during sun exposure. Vitamin D (in its active form, which is created after several modifications by the body) functions as a classic steroid hormone, which means it binds to nuclear receptors in various tissues to influence the expression of genes, thereby affecting a range of processes, especially the regulation of calcium.
It has long been known that vitamin D is crucial for healthy bones. The presence of vitamin D in the small intestine aids in the absorption of dietary calcium—people with vitamin D deficiency are able to absorb only a third to half as much calcium as those with sufficient levels—and calcium is vital to the hardness of bone. The two diseases traditionally associated with severe vitamin D deficiency—rickets in children and osteomalacia in adults—are characterized by deformation or softening of bone. And chronic vitamin D deficiency is strongly linked to osteoporosis, a disease defined by loss of bone density and associated with increased risk of fractures.
The common assumption has been that with the fortification of milk, instituted in the United States in the 1930s, and casual exposure to sunshine, most people get all the vitamin D they need. But a small resurgence of rickets in the last few years, particularly among African-American children, has caught the health-care community off guard. As studies have probed the issue, it has become clear that vitamin D deficiencies are far more widespread than researchers had expected. The elderly, who often receive little sun, are at particular risk, as are African Americans and other dark-skinned people, since skin pigmentation, which protects against damage by UV rays, also interferes with vitamin D production. (Those with dark skin need to spend more time in the sun to produce the same amount of vitamin D.) Infants who are exclusively breast-fed are also at high risk since breast milk, for all its virtues, contains almost none of this vitamin.
Perhaps the biggest surprise, though, has been the prevalence of vitamin D deficiency among women of child-bearing age—particularly African-American women—and among healthy children and adolescents. While severe cases early in life result in rickets, less-pronounced deficiencies may slip under the radar because they do not cause noticeable symptoms. Insufficient vitamin D can prevent proper bone development and increase the risk of disorders such as osteoporosis later in life.
Vitamin D deficiency can easily go undetected in adults as well. In the Mayo Clinic Proceedings, researchers in Minneapolis tested vitamin D levels in patients suffering from chronic, non-specific, musculoskeletal pain: 93 percent of them turned out to be vitamin D deficient—a condition very likely related to their symptoms. And of the East Africans, African Americans, and Hispanics in the study, 100 percent were vitamin D deficient!
But vitamin D’s benefits may go beyond the protection of bone and muscle. There is new research to suggest that vitamin D may also guard against an array of diseases, including colon, breast, and prostate cancers. More specific studies have examined levels of vitamin D in the blood directly, measuring them over time. Here, too, an inverse relationship has been found: lower vitamin D levels, higher risk of cancers.
Though the role of vitamin D in protecting against cancer has not been conclusively proved, the research is promising.
The potential role of vitamin D in forestalling other diseases, particularly autoimmune conditions such as multiple sclerosis, Type 1 diabetes, and rheumatoid arthritis, has generated widespread interest as well. The strongest studies have tested the role of vitamin D directly, with some fairly suggestive results. Although individual mechanisms are not well-established, it is known that active vitamin D interacts with cells of the immune system and very likely plays an anti-inflammatory role in the body.
Most vitamin D experts also argue that moderate UVB exposure—without sunscreen—is a key part of achieving adequate blood levels (except for people with a history of skin cancer or with medical conditions that make them abnormally sensitive to sun). The main reason for this is simply a pragmatic one: It is difficult to eat enough salmon and drink enough milk to attain the amount of vitamin D recommended. Children and adolescents drink much less milk than they used to, and, between lactose intolerance and calorie counting, most adults don’t drink milk at all. In addition, the vitamin D content in fortified milk has been found to be erratic, often differing from the amount promised on the label.
Only a small amount of casual sun exposure is needed to trigger enormous vitamin D production. Exact amounts are difficult to pinpoint since they depend on a person’s skin type and age, as well as on latitude, season, time of day, and amount of skin exposed. Slightly more time is required for people with dark skin. In addition, when vitamin D is obtained through sun exposure, there is no risk of toxicity, since UV light breaks down any excess vitamin formed. (For instance, this is why lifeguards, do not suffer from overdoses of vitamin D.)
Of course, any favorable mention of UV light is likely to cause some skin-cancer experts to balk. What also worries dermatologists is that a change in public health dogma may cause confusion, leading people to believe that if some is good, more sun is better.
In the end, however, it doesn’t seem terribly hard to find a middle ground. It is true that UV exposure can cause skin cancer; it is true that this reality has been distorted, perhaps deliberately, by commercial interests; and it is true that vitamin D is available in the form of oral supplements—for those determined to seek it out. But it is also true that many people simply aren’t getting enough of this crucial vitamin. And for most people, given its myriad benefits, both proven and potential, the advantages of a little sunshine very likely outweigh the risks.
Vitamin D:
Boosts Your Immunity:
Vitamin D is a potent immune system modulator. There is plenty of scientific evidence that vitamin D has several different effects on immune system function that may enhance your immunity and inhibit the development of autoimmunity.
Maintains Your Calcium Balance:
Maintenance of blood calcium levels within a narrow range is vital for normal functioning of the nervous system, as well as for bone growth, and also maintenance of bone density. Vitamin D is essential for the efficient utilization of calcium by the body.
Aids Your Cell Differentiation:
Cellular differentiation results in the specialization of cells for specific functions in your body. Differentiation of cells leads to a decrease in proliferation. While cellular proliferation is essential for growth and wound healing, uncontrolled proliferation of cells with certain mutations may lead to diseases like cancer. The active form of vitamin D inhibits proliferation and stimulates the differentiation of cells.
.Blood Pressure Regulation:
Adequate vitamin D levels may be important for decreasing the risk of high blood pressure. Again, more studies on vitamin D and hypertension are needed.
Has a Role in Insulin Secretion:
The active form of vitamin D plays a role in insulin secretion under conditions of increased insulin demand. Limited data in humans suggests that insufficient vitamin D levels may have an adverse effect on insulin secretion and glucose tolerance in type 2 diabetes. Still more studies are needed on the role of vitamin D and diabetes.
Vitamin D and Diseases:
According to the National Institutes of Health, vitamin D may play a role in the following diseases.
Vitamin D and Osteoporosis:
Osteoporosis is most often associated with inadequate calcium intake. However, a deficiency of vitamin D also contributes to osteoporosis by reducing calcium absorption. Adequate storage levels of vitamin D help keep bones strong and may help prevent osteoporosis in older adults, in those who have difficulty walking and exercising, in post-menopausal women, and in individuals on chronic steroid therapy.
Vitamin D deficiency, which is often seen in post-menopausal women and older Americans, has been associated with greater incidence of hip fractures. In a review of women with osteoporosis hospitalized for hip fractures, 50 percent were found to have signs of vitamin D deficiency. Daily supplementation with 20 800 IU of vitamin D may reduce the risk of osteoporotic fractures in elderly populations with low blood levels of vitamin D.
Vitamin D and Cancer:
Laboratory, animal, and some preliminary human studies suggest that vitamin D may be protective against some cancers. Several studies suggest that a higher dietary intake of calcium and vitamin D correlates with lower incidence of cancer. In fact, for over 60 years researchers have observed that greater sun exposure reduces cancer deaths. The inverse relationship between higher vitamin D levels in blood and lower cancer risk in humans is best documented for colon and colorectal cancers.
Additional clinical trials need to be conducted to determine whether vitamin D deficiency increases cancer risk, or if an increased intake of vitamin D is protective against some cancers.
Vitamin D and Alzheimer’s disease:
Alzheimer’s disease is associated with an increased risk of hip fractures because many Alzheimer’s patients are homebound, frequently sunlight deprived, and older. With aging, less vitamin D is converted to its active form. One study of women with Alzheimer’s disease found that decreased bone mineral density was associated with a low intake of vitamin D and not enough sunlight exposure.
Other Diseases Vitamin D Deficiency May Affect:
Autoimmune Diseases - Diabetes, Multiple Sclerosis and Rheumatoid Arthritis:
Diabetes mellitus, multiple sclerosis, and rheumatoid arthritis, are each examples of autoimmune disease. Autoimmune diseases occur when the body launches an immune response to its own tissue, rather than a foreign pathogen. Treatment with vitamin D has beneficial effects in animal models of all of the above mentioned diseases.
The results of several studies also suggest that adequate vitamin D intake may decrease the risk of autoimmune diseases. Evidence from animal models and human studies suggests that maintaining sufficient vitamin D levels may help decrease the risk of several autoimmune diseases, but more studies are needed to draw any solid conclusions.
Vitamin D and Hypertension (High Blood Pressure):
The results of clinical studies suggest an inverse relationship between serum vitamin D levels and blood pressure. Data from these studies suggest that conditions that decrease vitamin D synthesis in the skin, such as having dark skin and living in temperate latitudes, are associated with increased prevalence of hypertension. In randomized controlled trials of vitamin D supplementation, a combination of 1,600 IU/day of vitamin D and 800 mg/day of calcium for eight weeks significantly decreased systolic blood pressure in elderly women by 9% compared to calcium alone, but supplementation with 400 IU/day or a single dose of 100,000 IU of vitamin D did not significantly lower blood pressure in elderly men and women. Data from controlled clinical trials are too limited at this point to determine whether vitamin D supplementation will be effective in lowering blood pressure or preventing hypertension.
Vitamin D Toxicity:
It is very rare to have a vitamin D overdose. Vitamin D toxicity induces abnormally high serum calcium levels, which could result in bone loss, kidney stones, and calcification of organs like the heart and kidneys if untreated over a long period of time. Because the consequences of hypercalcemia are severe, the Food and Nutrition Board established a very conservative UL of 2,000 IU/day for children and adults. See Table below:
Infants 0-12 months - 1000 IU
Children 1-18 years - 2000 IU
Adults 19 years and older - 2000 IU
Vitamin D Drug Interactions:
The following medications should not be taken at the same time as vitamin D because they can decrease the intestinal absorption of vitamin D:
Cholestyramine (Questran), orlistat (Xenical), colestipol (Colestid), mineral oil, and the fat substitute Olestra. The oral anti-fungal medication, ketoconazole, inhibits the 25(OH)D3-1-hydroxylase enzyme and has been found to reduce serum levels of 1,25(OH)D in healthy men . The induction of hypercalcemia by toxic levels of vitamin D may also precipitate cardiac arrhythmia in patients on digitalis (Digoxin).
The following medications increase the metabolism of vitamin D and may decrease serum D levels:
Phenytoin (Dilantin), phenobarbital (Luminal), (Tegretol), fosphenytoin (Cerebyx), and rifampin (Rimactane).
Vitamin D3 Supplements:
It is not always practical to get your vitamin D from sunshine, and quite difficult to get adequate amounts from your diet so for many people, a vitamin D supplement is a practical way to ensure adequate levels of this important protector are always available in your bloodstream.
Since a large body of science shows vitamin D works closely with calcium and magnesium, it is best to take your vitamin D in combination with calcium and magnesium to maintain a proper balance.
Taking care of you naturally, the way life was meant to be.
Posted: October 15th, 2008 under Alternative Medicine, Home Remedies, Natural Health, Vitamin D, natural cures.
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