Vitamins and Bone Health
Ensuring you have a well balanced diet which contains high quantities of the important vitamins for bone health can help you form strong and healthy bones, and maintain good bone health. Proper nutrition will not only keep your bones in top condition, but will also help to prevent bone diseases such as osteoporosis and can help to prevent stress fractures.
Vitamin D is universally known to be of great benefit for good bone health, yet this vital vitamin is primarily synthesized by the body and is not strictly necessary for it to come from the diet. Exposure to sunshine enables the body to synthesize vitamin D with is vital for the formation of strong and healthy bones. Vitamin D is not needed directly, but is vital to help with the absorption of calcium from the diet.
Aside from Vitamin D, all other vitamins must come from dietary sources. There are many vitamins which play an important role in the formation and maintenance of healthy bones and teeth. A deficiency in any of these vitamins can lead to weakened bones, and an increased chance of developing stress fractures and a host of other bone and health problems in later life.
The intake of vitamins and bone health are strongly linked, with the role of common and less well known vitamins for good bone health listed below. You should make sure that your diet is varied and includes the foodstuffs mentioned below in order to keep your bones strong and healthy and to get your recommended daily intake. If this is not possible, or you feel you may not be getting all of your vitamins on a daily basis, taking vitamin supplements can be beneficial not just for the health of your bones, but also for health in general.
Vitamin A and Bone Health
Vitamin A is consumed in two forms in the diet; retinol and beta carotene. Retinol is readily available for use by the body, whereas beta carotene first needs to be converted to retinol before it can be used. Vitamin A is important for many bodily functions, and plays an important role in the health of the eyes, reproductive health, the skin and for cellular function in addition to the formation and maintenance of healthy bones.
While a deficiency in vitamin A can be bad for the bones, there has been more concern of late about an taking an excess of this vitamin, in particular that of retinol. It is not retinol from the diet or from vitamin supplements which is the problem, but from certain skin treatments. Many creams contain retinol, which can be absorbed through the skin. When too much retinol is taken into the body it is believed to stimulate osteoclasts – the cells in the body which are responsible for breaking down bone. Research also indicates that Vitamin A may have a negative effect on vitamin D which is vital for the absorption of calcium from the diet. Too little vitamin A is bad for the bones, and too much can similarly be bad. If you are considering taking vitamin supplements you should look for those which contain beta carotene rather than retinol. It is not believed that beta carotene can be bad for the bones.
Best Dietary Sources of Vitamin A
Retinol can be found in animal products, with liver and eggs containing the highest sources of dietary retinol. Beta carotene is the most common form of this vitamin in fruit and vegetables. As a general rule of thumb, dark orange fruits and vegetables are the best sources of beta carotene. Carrots, sweet potatoes, pumpkin, squash and cantaloupe melons all contain good amounts of beta carotene, as do dark green leafy vegetables such as kale and spinach.
Recommended Dietary Allowance (RDA) of Vitamin A
The recommended daily allowance of vitamin A varies with age, with adult males requiring 900 mcg per day and women needing 700 mcg. Children need 400 mcg up to 6 months, 500 mcg from 7-12 months, 300 mcg between ages 1 and 3, 400 mcg up to 8 years old, and 600 mcg up to 14 years of age. Over 14 years of age children require the same dose as adults.
Vitamin B12 and Bone Health
A number of studies have shown that there is a strong link between levels of vitamin B12 and osteoporosis¹, not only in women but also in men. Although the mechanism by which vitamin B12 can reduce the risk of stress fractures and osteoporosis is not fully understood, ensuring sufficient levels of vitamin B12 appears to offer some protection against this bone weakening disease. The main sources of vitamin B12 are meat and dairy products; and while the required levels of this vitamin are relatively low, many people have trouble absorbing sufficient quantities from the main sources of vitamin B12. Also, since vitamin B12 is water soluble, it cannot be stored in the body and needs to be consumed on a daily basis.
Some studies have had trouble pinpointing whether it is vitamin B12 or its co-enzyme folic acid which is providing protection from osteoporosis by augmenting bone mineralization. However since B complex vitamin supplements contain folic acid alongside vitamin B12, for most people it is a moot point and taking a daily supplement provides both of these B vitamins in sufficient quantities. Recent research also shows that vitamin B6 can also be of benefit to the bones; another vitamin contained in B-complex supplements.
The B vitamins are involved in reducing levels of homocysteine in the blood, which has been strongly linked with an increased risk of developing osteoporosis. B vitamins therefore should help to reduce the risk of developing this disease.
Best Dietary Sources of Vitamin B12
The most plentiful sources of vitamin B12 is meat, liver and dairy products, with only 3 ounces of beef containing the minimum recommended intake of vitamin B12. Milk and cheese are also good sources, as are oily fish with trout and salmon especially high in this vitamin. Haddock and clams contain very high levels of vitamin B12. Vegans may need to consume products which have been fortified with vitamin B12 to prevent vitamin B12 deficiency, and the over 50’s should also try to consume increased levels of this vitamin. Brewer’s yeast is a good supplement to take to give the body a B12 boost, although B-Complex supplements will provide the full range of B vitamins. Adults and children over 14 years of age should consume 2.4 mcg of vitamin B12 per day, with 4-8 years olds requiring 1.2 mcg, and 9 to 13 year olds 1.8 mcg.
Adults who suffer from pernicious anemia or low stomach acidity tend to have trouble absorbing this vitamin, and may therefore benefit from taking B-complex supplements to ensure an adequate daily intake. Vegetarians and vegans are particularly prone to vitamin B12 deficiencies. Medical conditions which affect the body’s ability to absorb this vitamin include atrophic gastritis (up to 30% of older adults have this condition), Crohn’s disease and celiac disease.