October
2007
The Sunshine Vitamin
Though well known and recognized, Vitamin D could easily be considered one of the most overlooked and ?taken for granted? of the basic vitamin group. Reports vary in their findings but it is claimed that one out of every seven, to one out of every eleven, adults are Vitamin D deficient. In related studies, claims of over 40% of the people hospitalized were found to be deficient in Vitamin D, and, nearly 40% of the people were diagnosed with a Vitamin D deficiency despite claims that they were consuming the recommended dose. Why are these are scary numbers for such a common, well known, vitamin?
Drink your milk then go outside and play. In an effort to eradicate the children?s bone disease known as Rickets during the 1930s milk was fortified with 400 International Units (IU) of Vitamin D per quart. Unfortunately, one cup of Vitamin D fortified milk offers only ?th of the minimum daily recommended amount, of 200 IU, for the average adult. For years milk has been considered to be a good source of Vitamin D, which it is, and since it is the most recognized dairy product many people have tended to believe that all dairy products are a good source of Vitamin D. This misnomer has slowly worked its way into the thinking of the well minded, but, unless specifically advertised, many other dairy products such as cheese, ice cream, and yogurts are not fortified with Vitamin D, with the exception of egg yolks.
The minimum daily requirement of 200 IU of Vitamin D has also been challenged. While 200 IU is considered enough to stave off Rickets by 1930s standards, contemporary research considers 200 IU woefully inadequate. By contemporary standards, 400 IU of Vitamin D, either in food or supplement form, with daily dose of sunshine is considered a safe baseline for the average adult. This Vitamin D recommendation changes for those who live in Northern climates during the winter months, or for those who receive little ultraviolet UV, or sunshine, exposure. Without the benefits of UV exposure the baseline for Vitamin D rises to 600 IU daily. Vitamin D deficiency among the elderly is also common and a concern for prevention of osteomalacea and osteoporosis since Vitamin D is essential for calcium absorption. Recommendations for the elderly can jump to 1,000 IU daily to preserve bone density but at this point it is highly recommended to consult a qualified medical professional to avoid Vitamin D toxicity.
With exposure to sunlight or UV rays a form of cholesterol is triggered or formed at the lower skin levels and synthesized into Vitamin D. As a general rule, the darker the skin pigment the longer UV exposure is necessary to acquire or manufacture the same amount of Vitamin D. Apparently a stop mechanism is also present, turning off Vitamin D production, from UV rays since those with high exposure do not experience Vitamin D toxicity. However, this is not true when taking Vitamin D supplements so avoid over or mega-dosing and consult a qualified medical professional if considering any large jumps in Vitamin D consumption. Most Calcium supplements contain Vitamin D already so be aware of how much you may be taking.
Being a fat soluble vitamin it is recommended that any Vitamin D supplement should be taken with a meal, or at least a snack, of good or neutral fat value. The primary function of Vitamin D is considered to be the absorption, or transport, of Calcium into the bloodstream through the walls of the small intestine. Without Vitamin D less than 20% of the available Calcium would be absorbed. If the body experiences a shortage in Calcium, Vitamin D also transports Calcium from the bones and into the bloodstream. Vitamin D plays a part in providing adequate levels of insulin and can be found in the Pancreas to the point that some studies suggest supplementation may increase insulin production offsetting some forms of Diabetes. Vitamin D has also been found to positively affect blood cell formation when Vitamin D receptors are found in both cancerous and normal blood cells thus reducing negative proliferation. Though not considered a cure, it has been noted that many men with prostrate cancer also demonstrate a Vitamin D deficiency, as well as many studies pointing towards Vitamin D as a cancer preventative. Vitamin D also plays a role in the proper phosphorus balance, healthy nerves, aluminum absorption, maintaining the heart muscle, and regulating proper blood pressure. ?
The liver plays an active role in the conversion of Vitamin D into its hormone form. Alcohol abuse or natural occurring liver problems may contribute to a Vitamin D deficiency since they can produce it but not necessarily activate it into the hormone form. Strict vegetarians are also at risk unless they make up for it by UV exposure. Often those experiencing seasonal depression are lacking in Vitamin D and can reverse the effects by visiting a tanning booth or changing household light bulbs with those that emit UV rays.
Cod Liver Oil is considered an excellent source of Vitamin D as well as most ocean or oily fish. Mothers who breastfeed should also be aware that there is little Vitamin D in breast milk and this risk increases with minimal UV exposure to the infant and the mother.
People affected by hyperparathyroidism, sarcoidosis, a sensitivity or hypersensitivity to Vitamin D, though usually Vitamin D deficient, should not supplement Vitamin D unless directed by a qualified health professional. A 400 to 800 IU, also depending on how much sunlight or UV exposure, should be plenty for the average healthy adult.
Those participating in highly active, extreme sports or bodybuilding may consider an above average increase but should exercise caution. Between UV exposure, and the increased use of Calcium, with Vitamin D added supplements, this should usually be enough to satisfy the bodies need under extreme conditions without having to supplement Vitamin D alone.