Vitamins are healthy. This we already know. Vitamin D has its place in our world as much as its cousins, C, B,E, & A do.
The importance of vitamin D was (more or less) reached around the turn of the 20th Century when other vitamins were also becoming known during various clinical tests. In D's case, it was the fourth time such a breakthrough was discovered, so alphabetically, it made sense that this was to be named... D! It came about from attempting to rid sick dogs of rickets, a disease which causes severe skeletal deformities. High doses of cod liver oil, was deemed the most effective. It was unknown at that time that the properties of vitamin D could be linked to UV light, thereby causing a synthesized effect in humans. As these benefits became clear, D would adopt the nickname, "the sunshine vitamin".
Vitamin D is responsible for promoting the absorption of calcium in our bodies. This process aids in bone formation as well. As with most things we ingest, there's always a happy medium to be achieved for maximum benefit. Overdosing is as bad with vitamins, as it is with drugs or alcohol. Studies have shown that too much, or even too little of vitamin D can cause the body to function abnormally and age prematurly. The importance of vitamin D, is such that most people above infant age living in North America, should have about 600 units per day. For those over 70 years old, the RDA is 800. Most bottled forms of D sold over the counter are often 1000 IU's. If consumed as a multivitamin, it's usually in the RDA range. Those who would benefit from receiving it in pill form, are those who either have a known deficiency, spend a lot of time indoors, or perhaps fall within the elderly range. More on that in a moment. Recommendations for European consumption are double that of the American/Canadian RDA.
Receiving vitamin D via UV rays, and the suggested amount of time that someone needs to be exposed, has been difficult to average. It is believed however that being exposed to direct sunlight between 10 AM and 3 PM, for up to 30 minutes, WITHOUT using sunscreen, should provide an ample amount of the vitamin. The exposed skin should be the face, the arms, legs or the back. It's also noteworthy to know that outdoor exposure is key. UV rays cannot penetrate glass, so sitting indoors by a sunny window doesn't count! Sunscreen with an 8 or above SPF, appears to sufficiently block the UV rays that provide vitamin D. It would seem then that sunscreen manufacturers are going overboard by either falsely marketing their products, or, in order to charge more, are giving us the impression that we need a sunscreen protection factor of at least 40 or above! Naturally if we're told to restrict our exposure to UV rays, then vitamin D needs to come from other sources. Considering the importance of vitamin D, we definitely need to receive the right amount no matter what form it comes in.
Getting beneficial amounts of vitamin D (other than through a pill) shouldn't be a problem. Not surprisingly though most people don't consider cod liver oil a delicacy - although it's loaded with vitamin D. Other tastier sources include many forms of fatty fish. This includes swordfish, salmon, tuna and sardines. Many products are vitamin D fortified, most namely milk, and in recent years, orange juice as well. Breakfast cereals, eggs, and yogurt also provide a healthy dose.
There are a host of reasons why some individuals may have a vitamin D deficiency. Those of advanced years will often make up the largest group. Older skin is not as capable of synthesizing vitamin D as efficiently as someone younger. In most cases, a doctor can determine if you're getting enough of the vitamin, and will prescribe a higher daily dose if necessary.
Vitamin D can be received in many enjoyable ways. As with everything though, moderation is key.
