Vitamins: Just Do It

By Jeanie Davis / WebMD Medical News / Reviewed by Michael Smith, MD

It's an old but true analogy : Like that car that sits in your driveway, your body needs regular maintenance -- vitamins -- to keep the motor going, to help you get more miles before you're hauled off to the junkyard.

In the June 19 issue of The Journal of the American Medical Association, two Harvard researchers give us the lowdown on which vitamins work -- and which ones don't -- in the fight against heart disease and cancer. The upshot: Eating right keeps you healthy and gives you the complex vitamins your body needs to fight off cellular changes that lead to cancer,
heart disease, and osteoporosis, according to Robert H. Fletcher, MD, MSc, and Kathleen M. Fairfield, MD, DrPH, both with Harvard Medical School.

Virtually everyone in the general population is at risk, because we just don't eat right, Fletcher and Fairfield say. But elderly people, vegans, and alcoholics are at even higher risk. Multivitamin supplements play an important role in shoring up this deficiency. "We recommend that all adults take one multivitamin daily," writes Fletcher.

"This practice is justified mainly by the known and suspected benefits of supplemental folate and vitamins B-12, B-6, and D in preventing [heart disease and stroke], cancer, and osteoporosis, and because multivitamins at that dose are safe and inexpensive."And elderly people should take one multivitamin plus vitamin B-12 and D supplements, he says. Intake of these two vitamins is known to be low in the elderly.

After reviewing almost 40 years of research, the Harvard doctors found the following associations between certain diseases and vitamins:

• Heart disease -- Low folic acid levels in the blood increase the risk of heart disease. Taking folic acid supplements or eating more in the diet has been shown to help decrease this risk. Research on vitamin E has been conflicting -- with some studies showing a benefit and others not. Beta carotene supplements have not been shown to help prevent heart disease -- and may even increase the risk in smokers.
• Cancer -- Studies have shown a decrease in colon cancer in men and women taking folic acid supplements and in men with higher folic acid in their diet. Folic acid has also been shown to decrease breast cancer in women who drink alcohol regularly but not in nondrinkers. Vitamin E may be able to help decrease prostate cancer in men and deaths from this cancer.Lycopenes -- from tomatoes -- have been shown to help prevent prostate cancer as well. But beta carotene may increase lung cancer in smokers,although the research is somewhat conflicting.
• Osteoporosis -- Vitamin D along with calcium decreases bone loss and fractures in elderly people.
• Birth defects -- Folic acid decreases the risk of birth defects of the spinal cord. Doctors recommend that women begin taking folic acid supplements before getting pregnant. Although the researchers recommend a multivitamin for all adults, many studies have shown that foods are really the best way to get our daily
  supply of vitamins.

Food sources of these important vitamins:

• Folate -- dark-green leafy vegetables (like spinach), whole-grain cereals, fortified grain products (like bread and cereal), and lean meat * Vitamin B-6 -- poultry, fish, legumes, nuts, potatoes, and whole grains* Vitamin B-12 -- poultry, fish, eggs, milk
• Vitamin E -- salad oils, margarine, legumes, nuts
  
• Vitamin C is a strong antioxidant that promotes hormone production, woundhealing, and iron absorption. Though vitamin C does not seem to affect heart disease risk, it may decrease the risk of cancers of the breast, stomach, mouth, and esophagus -- mainly from a diet high in fruits and vegetables.
  

Let's face it, it's not really that hard to eat right these days. Making time for a weekly stop at the grocery store helps. Good old orange juice comes fortified with extra vitamin C and calcium. Cereal is premixed with dried fruits and nuts. Mini-carrots, already washed, are sold in handy little bags. Spinach comes pre-washed, too. Chop some into an omelet, top a sandwich with it, whatever. It's just so easy, once you get into the mindset.

How can one exercise smarter in extreme heat?

• Run earlier in the day. That's when traffic is lightest and air quality the best. Sucking in poison to overload your already taxed system is not a good idea. Pollution of over 0.15 parts per million usually warrants an advisory -- so be advised! Be especially careful in cities with the worst ozone pollution. For 2002, according to the American Lung Association, they are (in order) Los Angeles; Bakersfield, Calif.; Fresno, Calif.; Visalia-Tulare-Porterville, Calif.; Houston; Atlanta; Merced, Calif.;Knoxville, Tenn.; Charlotte, N.C.; and Sacramento, Calif.
• Wear light-colored, loose, absorbent clothing (lose the Spandex or even cotton, which can stay wet).
• Don't engage in strenuous workouts, even in a heated pool (you can get overheated and dehydrated in water.)
• Carry a frozen water bottle in the back of your shorts (feels good, too). * Seek shaded pathways.
• Exercise moderately -- 60% to 70% of maximum heart rate. Take
  breaks. Walk.
• Drink a couple of cups of room temperature water before leaving and more when returning. In between, slug back a cup or two every 20 minutes. * When it's over 90 degrees, hit the gym instead.
  

Myth: If you drink water when you exercise - you'll get cramps.

Truth: Guzzling fluids while biking, hiking, running or aerobicizing does not bloat your body or hamper your athletic performance. In fact, it helps. After an hour of exercise, your body can lose more than a quart of water, and if you don't replenish that fluid, you run the risk of
dehydration. More than simply making you feel parched, losing an excess of water during workouts can result in exhaustion, muscle cramps and loss of coordination - all of which can lead to injury and potentially fatal heatstroke. To prevent dehydration, drink eight ounces of water right before your workout, and eight ounces every 15 minutes during exercise. Afterward, gulp another eight ounces. And if you have a long, intense workout (more than 45 minutes), go for a sports drink such as Gatorade to replace lost electrolytes. (Electrolytes are nutrients that affect fluid balance in the body and are necessary in order for our nerves and muscles to function.)