Sunday, February 08, 2009

HEALTH WITH MALAYSIAKINI: Vitamin D for powerful muscles in teens

Vitamin D can boost muscle power
and force in adolescent girls,
says anew study.

7 Feb 2009,
the times india

The research will be published in The Endocrine Society’s Journal of Clinical Endocrinology & Metabolism (JCEM).

Vitamin D deficiency has been shown to have a significant negative impact on muscle and bone health, and can lead to conditions including osteoporosis and rickets.

"We know vitamin D deficiency can weaken the muscular and skeletal systems, but until now, little was known about the relationship of vitamin D with muscle power and force," said Dr. Kate Ward, Ph.D., of the University of Manchester in the U.K., and lead author of the study.

"Our study found that vitamin D is positively related to muscle power, force, velocity and jump height in adolescent girls."

To reach the conclusion, researchers followed 99 adolescent girls between the ages of 12 and 14 years.

[Vitamin D for powerful muscles in teens
Times of India, India ]

Ward and her colleagues took blood samples to measure the girls’ serum levels of vitamin D. Many of these girls were found to have low levels of vitamin D despite not presenting any symptoms.

Researchers used a novel outcome measure called jumping mechanography to measure muscle power and force. Jumping mechanography derives power and force measurements from a subject’s performance in a series of jumping activities.

Ward says this method of testing is ideal as the muscles required to jump are those most often affected in subjects with vitamin D deficiency. Girls without vitamin D deficiency performed significantly better in these tests.

"Vitamin D affects the various ways muscles work and we’ve seen from this study that there may be no visible symptoms of vitamin D deficiency," said Ward.

"Further studies are needed to address this problem and determine the necessary levels of vitamin D for a healthy muscle system,” the researcher added.

How much is enough?
Meanwhile, skeptics doubt many of the health claims and question the need and even the validity of widespread testing. They recall how large doses of vitamins C and E were supposed to prevent cardiovascular disease. Beta-carotene was supposed to prevent lung cancer. Selenium kept prostate cancer at bay. None of it turned out to be true, and some of the advice even proved harmful.

Vitamin D was discovered 87 years ago by team of scientists at Johns Hopkins University who cured mice with rickets by feeding them cod liver oil. Oily fish like sardines remain one of the few natural food sources of vitamin D.

It was later found that certain wavelengths of ultraviolet light prompt our bodies to synthesize vitamin D, eventually making a hormone called calcitriol that, among other things, controls how the body uses calcium and mineralizes bone.

[Experts: We're in Vitamin D Deficiency Crisis
NBC Bay Area, CA ]