The sunshine vitamin may improve heart function in people with chronic heart failure, according to results from a double-blind study published in the Journal of the American College of Cardiology. For the study, researchers recruited 229 patients who had chronic heart failure due to left ventricular systolic dysfunction (failure of the heart to pump blood to the body) and a vitamin D deficiency. The patients were randomly assigned to receive either a 4,000 IU vitamin D3 supplement or a non-calcium-based placebo every day for one year. At the beginning and end of the study, researchers measured how far the patients could walk in six minutes and how much blood the patients’ hearts pumped with each heartbeat. At the end of the study, researchers found that:

• For patients taking the vitamin D3 supplement, heart function improved: the amount of blood pumped with each heartbeat increased by about 6%. There was no change in heart function seen in those taking the placebo.
• Left ventricle size diminished in the vitamin D3 group but not in the placebo group. In chronic heart failure, the left ventricle size increases as pumping capacity decreases, so a decrease in ventricle size indicates long-term improvement in heart function.
• Despite these positive changes, taking the vitamin D3 supplement was not associated with improvement in the patients’ walking distances.

This is the first evidence suggesting that vitamin D3 improves heart function in people with chronic heart failure. Older people, who have a higher risk of heart failure, have extra reason to watch their vitamin D levels, as our ability to make vitamin D declines with age. It’s also a good idea for people of all ages to keep an eye on their vitamin D status, since research has associated low levels with shorter lifespans, poor bone health, and more injuries in active people. Besides sunlight, sources of vitamin D include fish oil, eggs, and fortified cereals and milk. A vitamin D supplement may also be a good choice, but be sure to check with your doctor before adding any new supplement to your routine.

Source: Journal of the American College of Cardiology