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Should you be taking Vitamin D this winter?

This edition of Health and Wellness offers a quick rundown of the latest research on the subject
question thinking woman

Most likely. The standards set for nutritional minimums peg vitamin levels at those that prevent disease. Vitamin C prevents scurvy so you need a certain amount. Vitamin D is largely to prevent “rickets” (disease of weakened bones). But nutritional therapy can be used to enhance health, not just prevent problems.

Vitamin D is often called the “sunshine vitamin” as that is an urban human’s primary source. It takes about 20 minutes of direct exposure to sunlight a day to encourage your body to produce the chemical. The angle of the sun during six months of the Canadian year does not allow for enough exposure. There are Vitamin D rich foods but most of us don’t consume adequate quantities of oily sea creatures to qualify.

Here is a quick run down of the latest research that supports supplementation for Vitamin D:

1. Increase muscle mass and prevent fracture: A summary of the evidence comes from a combined analysis of 12 fracture prevention trials that included more than 40,000 elderly people, most of them women. Researchers found that high intakes of vitamin D supplements—of about 800 IU per day—reduced hip and non-spine fractures by 20 per cent, while lower intakes (400 IU or less) failed to offer any fracture prevention benefit.

Vitamin D may also help increase muscle strength, which in turn helps to prevent falls, a common problem that leads to substantial disability and death in older people. Once again, vitamin D dose matters: A combined analysis of multiple studies found that taking 700 to 1,000 IU of vitamin D per day lowered the risk of falls by 19 per cent, but taking 200 to 600 IU per day did not offer any such protection.

2. Prevent heart disease. The heart is basically a large muscle, and like skeletal muscle, it has receptors for vitamin D. So perhaps it’s no surprise that studies are finding vitamin D deficiency may be linked to heart disease. The Health Professional Follow-Up Study checked the vitamin D blood levels in nearly 50,000 men who were healthy, and then followed them for 10 years. They found that men who were deficient in vitamin D were twice as likely to have a heart attack as men who had adequate levels of vitamin D. There’s evidence that vitamin D plays a role in controlling blood pressure and preventing artery damage, and this may explain these findings.

3. Prevent Cancer. Nearly 30 years ago, researchers noticed an intriguing relationship between colon cancer deaths and geographic location: People who lived at higher latitudes, such as in the northern U.S., had higher rates of death from colon cancer than people who live closer to the equator. Since then, dozens of studies suggest an association between low vitamin D levels and increased risks of colon and other cancers. (1,27)  The evidence is strongest for colorectal cancer, with most (but not all) observational studies finding that the lower the vitamin D levels, the higher the risk of these diseases. Yet finding such associations does not necessarily mean that taking vitamin D supplements will lower cancer risk.

4. Boost Your Immune System. Vitamin D levels have been linked to less diabetes, multiple sclerosis, tuberculosis and especially respiratory infections. In fact, a recent randomized controlled trial in Japanese school children tested whether taking daily vitamin D supplements would prevent seasonal flu.

Given the high rates of vitamin D deficiency in North America, the strong evidence for reduction of osteoporosis and fractures, the potential cancer-fighting benefits of vitamin D, and the low risk of vitamin D supplementation, the recommend is widespread for vitamin D -3 supplementation of 2000 IU per day. The supplement is inexpensive and available in any pharmacy. You may not notice a big difference immediately (although personally I find it helps directly with Seasonal Affective Disorder or seasonal depression due to lack of light), but the long term results are worth it. Supplementation may not be necessary in the summer if you are outdoors, without sunscreen, for that 20 minutes direct exposure.

(Information for this article was researched from this source: