D is for Heart Health
Sunshine vitamin may help prevent heart failure
You may be aware that Vitamin D is important for bone health. But a growing body of evidence suggests that Vitamin D may also be good for heart health.
Research by Beth Israel Deaconess Medical Center cardiologist
Peter Kang, MD, is helping to shed light on the ways that Vitamin D may be able to prevent the development of congestive heart failure, a widespread problem in the U.S. population.
Congestive heart failure develops when the heart's pumping ability is diminished, resulting in inadequate amounts of oxygen-rich blood reaching the body. Symptoms of congestive heart failure can include fatigue, diminished exercise capacity, shortness of breath and swelling, all of which can greatly impede a patient's quality of life.
Sources of Vitamin D include sunlight, fatty fishes like salmon, beef liver, eggs, fortified foods like milk, and dietary supplements.
"Heart failure occurs in epidemic proportions in the developed countries and, unfortunately, despite significant progress in the treatment of heart failure, it is the leading cause of hospitalization and death in the United States," explains Kang, who is also an Associate Professor of Medicine at Harvard Medical School.
"Vitamin D is an interesting molecule," he adds. "It's actually a steroid-like hormone with multiple functions." Kang notes that while these include well-known functions such as bone metabolism and mineral regulation, it has also been shown that Vitamin D is involved in such functions as immune regulation. And, he adds, "Studies now strongly support the association of Vitamin D deficiency with an increased risk of developing heart diseases, including cardiac hypertrophy and heart failure."
Cardiac hypertrophy develops when the heart's muscle grows thicker, leading to a decrease in the size of the heart's chamber and eventually resulting in diminished pumping ability and the development of congestive heart failure.
"We wanted to learn whether treatment with Vitamin D could help prevent cardiac hypertrophy from developing into full-blown heart failure," says Kang.
Kang and his colleagues had previously shown that Vitamin D therapy blocks the development of cardiac hypertrophy and cardiac dysfunction. More recently, he and his colleagues studied a group of laboratory rats that had developed cardiac hypertrophy. The animals were given a Vitamin D compound together with an ACE inhibitor drug (the standard treatment for patients with chronic heart failure.) A second group of animals were treated with only the ACE inhibitor.
"Based on the results of this latest research, as well as our earlier findings, it seems that Vitamin D deficiency may be an under-recognized, non-classic risk factor for heart failure, but a risk factor that is readily correctable," he notes. "Although these findings are clinically important, it's also important to note that the molecular mechanisms that are involved in Vitamin D signaling are still poorly understood, and the doses of Vitamin D that would be needed for beneficial cardiac effect are not clearly known. More work needs to be done to better answer these questions, and to help guide our efforts to target Vitamin D therapy as a potentially viable and novel strategy for treating patients with cardiac hypertrophy and heart failure."
Posted August 2011