Vitamin Deficiency

This is a significant advantage,because vitamin D is a particularly difficult nutrient to obtain in a regular diet. The only edible substance which contains the vitamin is fish liver oil.

Dr Surender Kumar,chairman of the department of endocrinology and metabolic diseases at Sir Ganga Ram Hospital,said,“There is a misconception that dairy products contain vitamin D. There are only two known sources of vitamin D,fish liver oil and sunlight. It helps to expose the whole body to the sun for about half an hour every day until the skin is mildly red. We thought earlier that this was important only for bone health,but we now know that cardiovascular health,immunity and even cancer prevention could be among its roles.”

Figures for the incidence of vitamin D deficiency are fuzzy and incomplete,and there is no consolidated national estimate. Whatever is known is,however,alarming enough for numerous articles in medical journals over the last few years to call for a national programme — similar to the interventions for deficiencies of vitamin A and iodine — to tackle the problem.

Some doctors estimate that if a blood vitamin D level of 30 nanogram per decilitre is taken to be the deficiency cut-off,up to 90% Indians could be deficient.

Figures from small-sample studies extrapolated to the entire population appear to corroborate this estimate. A study done in 2000 found that 90 per cent of apparently healthy subjects in Delhi were suffering from hypovitaminosis D (deficiency).

Vitamin D helps in the mitigation of diabetes and high blood pressure,and plays an important role in immunity the prevention of some cancers — even though UV rays necessary for vitamin D synthesis in the skin have also been associated with skin cancer.

At the molecular level,vitamin D is now believed to modulate all these functions by its role in the regulation of the calcium receptor in the cell membrane. This decides the intracellular levels of calcium.

Calcium is a potent agent in all cellular functions of the body along with other ions like sodium and potassium.

A recent study published in the British Medical Journal says that people who take at least 500 mg of calcium supplements every day are 30 per cent more likely to suffer a heart attack,though excess calcium ingested in food does not seem to have quite the same effect on cardiac health.

In a way,the study reinforces the role of vitamin D in regulating calcium levels.

Dr Kumar has a simple explanation for the lack of vitamin D in Indians. “The rich do not get enough sun because they live in AC houses,work in AC offices and travel in AC cars,while the poor have too much melanin in the skin for sunlight to penetrate and vitamin D to form,” he says.

To counter the lack of vitamin D in natural food items,many developed countries including the US and Canada have been fortifying milk with vitamin D. That,experts say,is one of the ways India can consider to tackle this problem.

In an editorial published in November 2011 in the Journal of the Association of Physicians of India (JAPI), Dr Vikram Londhey of Mumbai’s Topiwala National Medical College and BYL Nair Charitable Hospital wrote,“Although there is adequate sunshine in India,high temperatures during the daytime and sultry and humid climate in many areas are the deterrents to follow the advice about sun exposure. Hence,food fortification with vitamin D is a good option to solve this problem. Food fortification and public health policies for vitamin D supplementation and dietary guidelines for adequate calcium for Indian population should be formulated and implemented.”