Vitamins can be divided into two groups; water soluble and fat soluble. Water soluble vitamins make up 9 of the 13 vitamins used by humans. Water soluble vitamins (B complex and vitamin C) dissolve readily in water and are easily excreted from the body. They are not stored by the body and should be consumed daily. Fat soluble vitamins are absorbed in the intestinal tract with the aid of fats or lipids. These vitamins are stored by the body when they are not used, so daily consumption is not necessary.

Vitamins A, D, E and K make up the fat soluble vitamin group. These vitamins are not easily destroyed by food preparation, cooking, or storage like water soluble vitamins. Because of this and the fact that the body stores excesses in the liver and fatty tissues of the body, deficiencies are rare in the US.

Vitamin A is a nutrient necessary for proper bone, eye and tooth development. It is also responsible for many other bodily processes, including night vision and keeping the mucous membranes in the lungs, sinuses, mouth, nose and throat moist. Vitamin A is found mainly in fish, liver and dairy products. Deficiency can cause night blindness, blindness, and severely dry eyes and skin.

The human body can convert beta-carotene into vitamin A. So, other sources for getting your vitamin A include yellow and orange fruits, like mangoes and apricots. Vegetable sources include carrots, pumpkins, and dark green leafy vegetables. Because toxicity is more of a concern than deficiency, many dieticians recommend getting vitamin A from beta-carotene sources. You can check the label of your multi-vitamin to see if the vitamin A is in the form of beta-carotene.

If too much beta-carotene is stored in the liver, it can prevent the liver from storing other fat soluble vitamins. Also, once it is stored there, it cannot be converted into vitamin A. Therefore, you should be careful about how much you take if you are supplementing. Always work with your doctor when you’re on a vitamins and supplements regimen.

Vitamin D is necessary for the body to absorb and use calcium. Vitamin D is crucial in the development, restructuring, and healing of bones. Vitamin D is usually added to dairy products, but can also be obtained from sun exposure or oily fish, like cod, salmon and sardines.

Deficiency is more common with vitamin D than any of the other fat soluble vitamins. Our need for vitamin D increases as we age and our absorption of it decreases. Many people have trouble absorbing it or have difficulty maintaining adequate levels of vitamin D, so they are advised by their physician to take it in the form of vitamin D-3 instead. This is the form of vitamin D that is normally produced in the skin with sun exposure.

Insufficient levels of vitamin D have been associated with an increased risk of autoimmune disease, high blood pressure, depression, and even cancer. When you visit your doctor, have them test your vitamin D levels and advise you on whether or not you should supplement.

Part 2 in the series “Fat Soluble Vitamins” will review the vitamins E and K. Remember to ask your doctor about supplementing with vitamins before you start to avoid drug interactions. If you do take vitamins and supplements, you can buy vitamins, wholesale vitamins, or discount vitamins online to reduce the cost of supplementing.

About the Author: Phil Le Breton is owner at Wholesale Nutrition. He has a strong interest in helping people achieve greater brain and body health with vitamins and supplements. Wholesale Nutrition has provided the world with discount vitamins and the best vitamin C since 1970. Visit http://www.nutri.com to buy high-quality, low-cost wholesale vitamins today!