The following stories appear in full on today's Vidyya Medical News Service Web site.
On Tuesday, Vidyya reported that fruits and vegetables do not provide as much of the essential vitamins as previously thought. As a result, new recommendations have been issued for several known vitamins and minerals. To round out this week, we will be presenting information on six of the substances that have been the target of the new recommendations. Today's issue features information on vitamins A, D and E. Tomorrow's issue will contain updated knowledge regarding magnesium, selenium and zinc.
For more information: A Two Issue Look At Vitamins And Minerals
Vitamin A is a family of fat-soluble vitamins. Retinol is one of the most active, or usable, forms of vitamin A, and is found in animal foods such as liver and eggs. It can be converted to retinal and retinoic acid, other active forms of the vitamin A family. Some plant foods contain orange pigments called provitamin A carotenoids that the liver can convert to retinol. Beta-carotene is a provitamin A carotenoid found in many foods. Lycopene, lutein, and zeaxanthin are also carotenoids commonly found in food, but the body cannot convert them to vitamin A.
For more information: Facts About Dietary Supplements: Vitamin A And Carotenoids
Vitamin D, calciferol, is a fat-soluble vitamin. It is found in food, but also can be made in the body after exposure to ultraviolet rays from the sun. Vitamin D exists in several forms, each with a different activity. Some forms are relatively inactive in the body, and have limited ability to function as a vitamin. The liver and kidney help convert vitamin D to its active hormone form. The major biologic function of vitamin D is to maintain normal blood levels of calcium and phosphorus. Vitamin D aids in the absorption of calcium, helping to form and maintain strong bones. It promotes bone mineralization in concert with a number of other vitamins, minerals, and hormones. Without vitamin D, bones can become thin, brittle, soft, or misshapen. Vitamin D prevents rickets in children and osteomalacia in adults, which are skeletal diseases that result in defects that weaken bones.
For more information: Facts About Dietary Supplements: Vitamin D
Vitamin E is a fat-soluble vitamin that exists in eight different forms. Each form has its own biological activity,
the measure of potency or functional use in the body. Alpha-tocopherol is the most active form of vitamin E in humans, and is a powerful biological antioxidant. Antioxidants such as vitamin E act to protect cells
against the effects of free radicals, which are potentially damaging by-products of the body’s metabolism. Free radicals can cause cell damage that may contribute to the development of cardiovascular disease and cancer.
Studies are underway to determine whether vitamin E might help prevent or delay the development of those chronic diseases.
For more information: Facts About Dietary Supplements: Vitamin E
To further support the possibility that therapy to resynchronize the
failing heart's beating action may lengthen life span, in addition to keeping
patients more healthy, Medtronic, Inc., today announced enrollment
of the first patients in a major new European study with implications for
thousands of the world's heart failure patients.
European Study To Evaluate Hospitalization, Survival Of Patients Who Get Cardiac Resynchronization And Optimal Drug Therapy For Heart Failure
Today's Vidyya articles are:
As always, we hope you enjoy the issue.