A growing number of studies point to vitamin D deficiency as a risk factor for heart attacks, congestive heart failure, peripheral arterial disease (PAD), strokes, and the conditions associated with cardiovascular disease, such as high blood pressure and diabetes.
Vitamin D supplements may help people with diseased hearts, a study suggests.
A trial on 163 heart failure patients found supplements of the vitamin, which is made in the skin when exposed to sunlight, improved their hearts' ability to pump blood around the body.
The Leeds Teaching Hospitals team, who presented at a meeting of the American College of Cardiology, described the results as "stunning".
The British Heart Foundation called for longer trials to assess the pills.
Vitamin D is vital for healthy bones and teeth and may have important health benefits throughout the body but many people are deficient.
What is vitamin D?
Vitamin D acts as a hormone, regulating more than 200 genes throughout the body. It does an impressive amount of work. For example, vitamin D:
Keeps abnormal cells from multiplying in breast and colon tissues
Helps regulate blood pressure in the kidney
Helps regulate blood sugar levels in the pancreas
What causes vitamin D deficiency? Who does it affect most?