The Truth Behind 9 Popular Vitamin Supplements

Should you take supplements?Your body responds best to vitamins and minerals found in food. But not all essential nutrients are easily absorbed, which means some of us may not be getting what we need. Determine if you need to add to your diet with the latest research on nine popular vitamins and supplements.

Vitamin E
Vitamin E is an antioxidant, a substance that protects against the effects of free radicals - cell-damaging molecules that can play a role in heart disease, cancer and other diseases. Vitamin E also boosts your immune system. However, you may not need to add it as a supplement, warns Andrea N. Giancoli, RD, spokesperson for the Academy of Nutrition and Dietetics. "Most people get enough vitamin E from the foods they eat," say Giancoli. "Good sources are vegetable oils, nuts, seeds, and leafy greens. Vitamin E is also added to foods like cereals as a natural preservative." Another reason to stick with food sources: Vitamin E supplements may be harmful for people who take blood thinners and other medicines.

Vitamin C
Much controversy surrounds the idea that vitamin C can alleviate the common cold. But according to the National Institutes of Health, the majority of evidence shows that consuming large amounts may shorten a cold's course by about one day. "A high dose is 4,000 mg per day. I recommend taking four, 1,000 mg pills with lots of clear liquids," says Sarah Brett, RD, who teaches nutrition at the University of Idaho. "Vitamin C is water-soluble, so it works more effectively to flush out the virus when you drink a lot of fluid." Start at the first sign of symptoms.

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Calcium
As a dynamic tissue, bone is always in flux, either releasing calcium or depositing it. Your body needs enough of the mineral so that it does not have to take more from the bone than it can handle. But if you are 40 or older, do not assume you should be taking a calcium supplement. Data from almost 24,000 participants in the European Prospective Investigation into Cancer and Nutrition study found too much, as little as 2000 mg per day, can boost your risk of heart attack. ""Before reaching for a supplement, take an inventory of how much calcium you're already obtaining from the foods you eat regularly," says Giancoli. The recommended daily dose is 1000mg for women under 50 and 1200 mg for those over 50 and in menopause. If you eat three servings of dairy a day, you are likely getting adequate amounts. For a list of foods with the bone-strengthening mineral visit the NIH website.

Vitamin D
This important vitamin helps your body absorb calcium. If you don't get enough vitamin D, or your body doesn't absorb it well, you increase the risk for osteoporosis. Skin makes vitamin D when exposed to the sun, but sunscreen can reduce its production by 95 percent. Vitamin D is present in only a few fortified foods such as milk, yogurt, and orange juice, as well as fatty fish like salmon and tuna. For all these reasons combined, the National Osteoporosis Foundation recommends taking a daily 400 IU vitamin D supplement.

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Omega-3 Fatty Acids
For years experts have been telling us that to get enough heart and brain-protecting omega-3 fatty acids, we had to take supplements. The reason: Few foods contain these essential nutrients. But several new, large studies found participants showed no cognitive or cardiovascular benefit after taking the capsules. (The explanation is unclear; some researchers suggest that, overall, fish eaters have better diets.) Now, experts say to eat hearty doses of fish instead. "The recommendation is to eat fish at least twice a week. Salmon, mackerel, trout, and sardines have the highest amounts of these essential oils, but you can also opt for white fish like tilapia, halibut, and sea bass," says Giancoli. Allergic to fish or just not a fan? Partake in more flax, soy, canola, and walnuts.

Echinacea
Like Vitamin C, echinacea's effectiveness in preventing colds is up for debate among researchers. Several clinical studies report that taking echinacea as either a tea or supplement is not effective; however, others found it can decrease the odds of developing the cold by 45 to 58 percent. "The problem is that scientific studies have used different types of echinacea plants and different methods of preparation, so it's not surprising that results vary," says Brett. With no potential risks, it might be worth a try. "I've found echinacea seems to be most effective if started when symptoms are first noticed and continued for 7 to 10 days," says Brett. Daily dosage is two to four cups of tea or two, 2,000 mg pills per day.

Ginkgo
Although ginkgo is touted as a memory enhancer, most reports render those claims false. In fact, researchers at the University of Hertfordshire in the U.K - the first to look at the effect of the ancient plant on healthy people across all age groups - found zero impact on the cognitive functions regardless of age, dose taken, or length of time taking the supplement. This supports other recent studies indicating that ginkgo does not ward off Alzheimer's disease either. "Instead, boost your brainpower by tackling a new skill like learning to play a musical instrument or becoming a social media pro," says Brett.

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Black Cohosh
Exactly how Black Cohosh works is unknown, but the National Institutes of Health found that it significantly reduces the frequency of menopausal hot flashes. "Taking 40 to 100mg per day has shown to be comparable to a prescription of low-dose transdermal estradiol," says Brett. Though she warns it is not for everyone: Black cohosh should not be used by pregnant or lactating women, those with a history of breast cancer or hormone- sensitive conditions such as uterine and ovarian cancer, endometriosis, or uterine fibroids. The herb might also be linked to liver failure and autoimmune hepatitis.

Garlic
This odiferous root plant has been shown to have a bevy of health benefits when eaten fresh, (rather than aged or in supplement form). Fresh garlic may lead to lower blood pressure and a reduced risk of atherosclerosis, colon, rectal and stomach cancers, according to the U.S. National Library of Medicine. How to nosh on garlic without reeking? Chew on a few sprigs of parsley.

How do you ensure your body gets all the vitamins and minerals it needs? Let me know in the comments!

-by Holly St. Lifer

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