Vitamin D is essential for the proper formation of the skeleton. It is vital for bone growth and renewal as it helps our bodies absorb and retain calcium and phosphorus. Vitamin D is also required for nerve and muscle activity and can help combat chronic inflammation. Research is also determining that vitamin D may help keep cancer cells from growing and dividing.

If we have too little of this valuable nutrient, our bones are not able to mineralize properly. This can lead to a condition called rickets in children, which is characterized by bowed legs, knock-knees, swollen joints, and malformed skeletons. In adults, vitamin D deficiency leads to osteomalacia, a condition in which there is inadequate mineralization of the bone. Deficiency may also result in osteoporosis due to decreased calcum abosrption, and vitamin D deficiency has also been associated with muscle weakness.

Vitamin D is produced naturally in our body by exposure to the sun’s ultraviolet rays, and is also available in certain foods as well as supplements. Vitamin D is often referred to as the “sunshine vitamin” because we can make vitamin D out of a cholesterol compound that is naturally present in the skin when our skin is exposed to ultraviolet light from the sun. However, if we are not receiving the sunlight we need to manufacture vitamin D, we need to consume vitamin D fortified foods or take a vitamin D supplement.

Vitamin D production in our skin is greatly affected by the seasons and by the latitude at which we live. Here in Canada, we experience “vitamin D winter” between October and March because of the lack of sunshine and our ability to stay outdoors in the cold weather. “ Vitamin D winter” is also extended for those who live closer to the poles.

Although our bodies do have the ability to store vitamin D to a certain extent, it is wise to supplement in addition to the sun exposure we are able to obtain during the winter. In North America, on average, light skinned people need about ten to fifteen minutes of sun daily on our face and hands while darker skinned people need more, as vitamin D synthesis is poorer in dark skin. It is also important that we take care not to overexpose ourselves, which may increase the risk of skin cancer.

We know the best way to obtain vitamin D is from exposure to sunlight, but when we aren’t getting the sun we need to manufacture vitamin D there are a few foods that can help increase vitamin D intake, and there are also vitamin D supplements. Fortified dairy products, fortified orange juice, and fortified soy-milk are good sources of vitamin D. Margarine, eggs, chicken livers, salmon, sardines, herring, fish oils (halibut and cod-liver oils), and mushrooms all contain small amounts. Because dietary intake may not always provide enough vitamin D that our body requires, supplementation is necessary to obtain adequate levels.

Vitamin D isn’t only for adults either. Babies right trough teenagers need this important and essential nutrient also. As a matter of fact the American Journal of Clinical Nutrition released a study last January that found “low blood levels of vitamin D during pregnancy may result in less muscle and higher insulin resistance in children”. Even breast-fed babies and toddlers should receive the recommended dose of vitamin D drops daily.

You can visit the Health Canada website at: for a complete list of the updated Dietary Reference Intakes for both vitamin D and calcium as well as other related information.

As of July 2010, Osteoporosis Canada’s new guidelines recommend: “daily supplements of 400 to 1000 IU (international units) for adults under age 50 without osteoporosis or conditions affecting vitamin D absorption. For adults over 50, supplements of between 800 and 2000 IU are recommended. For people who need added supplementation to reach optimal vitamin D levels, doses up to the current “tolerable upper intake level” (2000 IU) are safely taken without medical supervision. Doses above that require medical supervision. A daily supplement of 800 IU should be regarded as a minimum dose for all adults with osteoporosis.”

There are two forms of vitamin D. Vitamin D2 (ergocalciferol, generally made from yeast) and vitamin D3 (cholecalciferol, manufactured from the skin of sheep, cows, and pigs, and from sheep’s wool). Vitamin D3 is the kind our body produces as a result of sun exposure. Although there is ongoing controversy among vitamin D experts about the safety and effectiveness of supplementing with vitamin D2 as opposed to vitamin D3, the basic difference between the two forms has to do with how they are manufactured and the costs associated with manufacturing. On the other hand, researchers have found vitamin D2 to be less effective as vitamin D3, so it makes sense for those who prefer to use the form of vitamin D that is not of animal origin, to increase their intakes of vitamin D2 accordingly.

Vitamin D has many health benefits and there is a vast amount of scientific evidence to prove it. Although it is most famous for its role (along with calcium) in maintaining strong, healthy bones, it is becoming increasingly clear that vitamin D provides many additional health benefits. Simply said, vitamin D is important to your health.

Author's Bio: 

A Member of The AIM Companies for over twenty-four years, Joanne Jackson takes pride in sharing her knowledge of nutrition and the AIM products with others. As an advocate of healthy eating and proper nutrition, Joanne understands that the choices we make, and choosing them wisely, is the key to wellness. Joanne holds a certificate in Nutrition: Studies and Applications, a certificate in Natural Health Fundamentals and a certificate in Sports and Fitness Nutrition. She is currently studying for her diploma as a Certified Holistic Nutritionist.