Vitamin D, also known as the sunshine vitamin, is a pro-hormone (a hormonal precursor) essential for calcium metabolism and building of strong bones. Vitamin D is required to prevent rickets, an illness that causes softening and weakening of bones in children. Adequate Vitamin D status during childhood and adolescence also help reduce the risk of osteoporosis in later life. Studies have also linked vitamin D deficiency to type I diabetes, high blood pressure, obesity, rheumatoid arthritis, asthma, bronchitis, Crohn's disease, multiple sclerosis and cancers of the breast, colon, prostrate and ovaries.
Sources of vitamin D:
About 80 to 90% of the vitamin D requirement is provided by synthesis of vitamin D in body when the skin is exposed to ultraviolet B radiation from sun and about 10 to 20% from dietary sources. Food sources of vitamin D include oily fish such as salmon, mackerel, sardines, cod liver oil, liver and organ meats, egg yolk. Fortified foods such as cereals, milk, orange juice, also provide some amount of Vitamin D.
Causes of vitamin D deficiency
Despite the abundant sunlight exposure in a tropical country like India, studies have shown that about 70 to 98% of Indian children and adolescents suffer from Vitamin D deficiency. Some of the reasons for the deficiency are:
- Competitive studies have decreased the amount of time children spend playing out in sun.
- Outdoor play time has been replaced with computers and smart-phones.
- The levels of pollution in India has increased substantially and has reduced the exposure of ultraviolet B rays from sun.
- Increased use of sun blocking creams in children and adolescents to prevent tanning reduces vitamin D synthesis drastically
- Wearing scarves on head for religious and cultural reasons also reduces exposure to sunlight.
- Lack of playgrounds in schools in metropolitans like Mumbai and Delhi.
- No vitamin D fortification.
Prevention is better than cure
Some simple steps to prevent vitamin D deficiency:
- Encourage your child to walk or use the bicycle instead of using rickshaws, buses or private cars to go to school.
- Encourage your child to go play in the sun for at-least half an hour every day.
- Avoid over-using sun blocking creams when the kids go down to play
- Schools should conduct physical training classes in open playgrounds with abundant sunlight
- If you have an infant (child less than 1 year of age) sunbathe him for 10 to 15 minutes daily
To conclude, here's a popular nursery rhymes that highlights the importance of sunlight exposure and vitamin D "The sun looks like an orange. Both are round and they both give us energy. The sun warms you up and orange juice cools you down. But both are good for your health. One gives you Vitamin C and the other gives u Vitamin D."