Vitamin D is a fat soluble vitamin that is obtained extensively from exposure to sunlight and through very few foods like egg yolk, fatty fish, cod liver oil, milk, breakfast cereals that are artificially fortified by vitamin D.
After obtaining vitamin D from either source or both, the vitamin is transported via blood to the liver and kidneys where it gets broken down by a
biological process known as hydroxylation thus preparing it to be utilized by the body.
This process occurs two times, first in the liver where vitamin D is converted into calcidiol, and second in the kidney where vitamin D is converted into calcitriol. Vitamin D can also be obtained from dietary supplements.
Benefits of Vitamin D
Vitamin D has many functions to play in the body. It is necessary for the body to stay fit and healthy.
This is one of the most important functions of Vitamin D. It is responsible in increasing the body’s ability to absorb calcium. The vitamin also helps in maintaining the calcium and phosphate concentrations in the bone required for the mineralization of the bones. Vitamin D is also needed for the growth and remodeling of bones.
Maintenance of immune system
Vitamin D is responsible in maintaining the general immune function of the body and increases body resistance to many diseases and viruses.
Prevention of heart disease
Researches show that individuals having lower levels of vitamin D are at a higher risk for heart diseases. Vitamin D can lower high blood pressure and can reduce the risk of type 2 diabetes. Both these factors are responsible for heart disease.
Reduction of anxiety and depression
Vitamin D plays a vital role in reducing anxiety and depression. Vitamin D is responsible for a strong central and peripheral nervous system and also helps in the synthesis of endorphins and other hormones in the brain that are involved in the reduction of anxiety and depression.
Not only determined by the calcium levels, weight loss is also determined by the vitamin D levels in the body. Various researches have shown that those who had increased the intakes of calcium and vitamin D have lost more weight than those who have cut down these nutrients.
Benefits of Vitamin D for women
Vitamin D brings a lot of benefits for women, especially those women after menopause who are at a risk for osteoporosis, heart disease and weight gain. Since vitamin D helps absorption of calcium and is responsible for keeping the bones strong thus, when the body fails to absorb and utilize calcium the bones are weakened that can lead to osteoporosis.
In women, estrogen greatly helps in keeping the bones strong but after menopause the estrogen levels fall down considerably leading to risks for bone loss and fractures. Vitamin D supplements along with calcium supplements can minimize the risks.
Also breast cancer risks in postmenopausal women can stay at bay by the consumption of vitamin D supplements. Cancer risks in ovary, colon, pancreas and skin can also be lowered by adequate vitamin D supply in the body.
Benefits of Vitamin D for men
Besides general health, vitamin D has some more benefits for men. Researchers have found that compared to men having inadequate levels of vitamin D, men with adequate levels of vitamin D have higher levels of testosterone which is a hormone responsible for muscle mass and strength, libido and decreasing body fat.
Vitamin D also reduces risks for sarcopenia in men which is a condition of losing muscle mass and strength. Vitamin D also reduces risk for prostate cancer. Researches conducted on the effects of vitamin D on prostate cancer have shown that vitamin D controls the prostate cancer cells from attacking the healthy cells by preventing the activity of the enzymes, though this sector requires more research.
Various researches also point out that in older men aged up and above 65 years of age and with higher levels of vitamin D had lower risks of death from heart diseases than those with lower vitamin D levels.
Benefits of Vitamin D supplements
Since vitamin D is not abundant in food sources and the only powerful source being the sun, in order to maintain the adequate levels of vitamin D in the body vitamin D supplements are useful. Supplements are available as either vitamin D3 or vitamin D2.
Vitamin D3, also called cholecalciferol is the form that is synthesized in the skin due to exposure to sunlight. Vitamin D2, also known as ergocalciferol is the form synthesized by plants. Both these forms D3 and D2 both can effectively raise the levels of vitamin D in the blood.
Vitamin D supplements can be beneficial when adequate exposure to sunlight is not possible that depends on a number of factors like climate, weather, shade, pollution, using sunblocks etc. which hampers the normal synthesis of vitamin D via skin.
Also in elderly people, the levels of vitamin D falls down due to liver dysfunction or kidney diseases and other causes, those are responsible for the processing of vitamin D and preparing it for utilization.
The intake of vitamin D is measured in terms of international units. With gradual decrease in the vitamin D levels, now it is recommended that the daily intake of vitamin D by the individuals should be 600 IUs. Infants are recommended 400 IUs/ day. However, the individuals should not cross 4,000 IUs/ day of vitamin D intake.
Effects of over-dose of Vitamin D
Though synthesis of vitamin D from sunlight and food sources have no risks of over-dose and hence free from any side effects, over-dose may occur in case of consuming vitamin D supplements. Consumption of more than 40,000 IUs per day can lead to vitamin D toxicity.
This can lead to an abnormal rise in blood calcium levels which in turn can cause bone loss, kidney stones and calcification of organs. Vitamin D supplements can also accompany certain mild side effects like vomiting, fatigue, itching, gastrointestinal disturbances, dry mouth, muscle problems, urinary irregularities etc.
Research is still on as to decide the exact amount that leads to over-dose due to the supplements of vitamin D. However, vitamin D supplements should be consumed only after the consultation of your doctor and prescribed amounts should strictly be followed.