Sunshine for the heart
Exercise and a healthy diet apart, you also need 45 minutes of sunshine each day to keep your heart healthy and strong. Rhythma Kaul writes.Updated: Sep 29, 2013 03:43 IST
Exercising and a healthy diet is not enough, you also need 45 minutes of the mid-morning sun for a healthy heart. It’s well established that Vitamin D, the “sunshine vitamin” that the skin synthesises on exposure to sunlight, is needed to build healthy bones, but now there is evidence that link the vitamin to heart health.
“Vitamin D-deficiency increases cholesterol deposition in the arteries, resulting in the hardening of the arteries. It also raises a person’s blood pressure, and all these factors together increase the risk of a heart attack by nearly 70%,” said Dr Ashok Seth, chairman, cardiac sciences, Fortis Escorts Heart Institute. A random survey of 871 people who came to the heart hospital for a preventive health check up in a month showed 84.3% were vitamin D-deficient, with nearly 70% of them suffering from moderate to severe deficiency.
The ‘D Heart Survey’ threw up other surprising findings. Younger people – between 30 years and 39 years – were the worst affected, with 94.5% of the deficit affecting people in this age group. One in four people were at high risk for heart disease with a little more than one in three – 36% – having low HDL (good cholesterol) levels.
“Normal vitamin D levels – 30.0 to 74.0 nanograms per milliliter (ng/mL) – halve the chances of developing heart disease and lower the chances of a heart attack by 70% from the baseline,” says Dr Seth.
The jury, however, is still out on whether vitamin-D deficiency is a risk factor for heart disease. “Low vitamin D levels are associated with left ventricular hypertrophy (enlargement of the muscle of the heart’s main pumping chamber), vascular dysfunction, and renin–angiotensin system activation (to regulate blood pressure). Despite a large body of experimental, cross-sectional, and prospective evidence implicating vitamin D deficiency in the pathogenesis of cardiovascular disease, a causal relationship remains to be established,” reported the European Heart Journal in April, 2013.
“There may not be a direct impact as such but vitamin D is known to provide relief from symptoms such as fatigue, muscular ache, cramps etc that are common side-effects of medicines that we prescribe to people for lowering cholesterol. The deficiency worsens these symptoms,” says Dr K K Talwar, chairman-cardiology, Max Healthcare.
Though the cause and effect is yet to be established, screening for vitamin-D levels is a standard test for people with heart disease. “Correcting the deficiency is necessary but supplementation should be taken only on prescription as an excess of vitamin D causes toxicity. The dosage has to be monitored regularly by a doctor,” Dr Talwar added.
Doctors recommend to opt for the sun to meet the daily vitamin D requirement. The process of vitamin D synthesis takes about 45 minutes, and the best time is between 10am and 2pm, with head, face, limbs and upper part of the body exposed to direct sunlight.
One must be careful that it has to be done without any break as the whole process gets reversed if one leaves the sun even for 5 min. “Foods fortified with vitamin-D, such as milk, are needed to meet the gap,” says Dr Rajesh Malhotra, professor, orthopaedics department, AIIMS.