Moaning about the temperature is a common pastime during a Winnipeg winter, but the cold weather has more of an influence on your health than you might think.

The lack of sunlight reaching our skin is cause for concern when it comes to our intake of vitamin D.

Most of the vitamins and minerals we require are not too difficult to incorporate into our diet when we know which foods they are found in. Vitamin D, however, is a special case.

Although it is found in a few natural foods, vitamin D is in its most potent form when our skin synthesizes it from sunlight. And this is simply not an option during many months of the year.

Vitamin D is essential for the absorption of calcium and phosphorous, two minerals that we need for strong bones and teeth. Even if we consume the recommended amounts of calcium and phosphorous in our diet, when we consume inadequate amounts of vitamin D the minerals can not be properly absorbed.

We need all three of these nutrients to protect and strengthen our bones, as well as to prevent many dangerous conditions and diseases such as osteoporosis, rickets, multiple sclerosis and several types of cancer.

A recent study published in the U.S. Journal of Clinical Endocrinology and Metabolism suggests that vitamin D is directly related to the development of muscle power and force.

Good food sources of vitamin D include egg yolks, milk, cod and halibut liver oil, salmon and tuna (among other types of fish) and green leafy vegetables. Other food products such as butter and orange juice are now being fortified with it as well.

Because few of us eat all of these foods on a regular basis and in large enough quantities, it might be a good idea to take a vitamin D supplement. Remember, however, that a supplement is not a replacement for real food and should only be used to complement your diet.

Vitamin D is a fat-soluble vitamin, meaning it is not flushed out of our system the way water-soluble vitamins are. This tends to be a good thing when our intake of the vitamin is reduced, as our body holds onto it and retains it.

Fat-soluble vitamins can also be dangerous when we consume too much all at once; our bodies keep the nutrient in our system and may reach toxicity levels.

When it comes to vitamin D, this is generally a danger that only comes from taking too many supplements, as it is highly unlikely that we consume enough foods with vitamin D in them on a regular basis to reach that extreme.

Over-zealous supplementation can lead to kidney stones, nausea, headaches, fatigue, and even weak bones and muscles (the very thing we’re trying to prevent!), among other symptoms.

University of Winnipeg student Sagan Morrow writes a health and wellness blog.

Published in Volume 63, Number 20 of The Uniter (February 12, 2009)