May 7, 2015

The Lowdown on 26 Popular Dietary Supplements

Hundreds of millions of us take dietary supplements every day, and for almost every reason under the sun.

While some of these supplements may show promise, there are repeated cautions that appear in most reviews of the topic:
  • Get what your body needs from your diet, not from pills.
  • Discuss supplements with your healthcare provider before taking them.
  • For most products, there have been no proper, scientific clinical studies to prove safety and efficacy.
  • Their long-term effects remain unknown.
  • Most supplements have many different varieties. There is continuing uncertainty about which variety (and what dosage) is best.

The special 2015 spring / summer issue of the Wellness Letter from the University of California at Berkeley includes an excellent eight-page review of the most popular products. Everything that appears in italics below comes directly from that informative publication.

Alpha-lipoic acid: A special antioxidant
The anti-oxidant ALA helps the body’s mighty mitochondria produce energy. Got issues with muscle strength or cognition? Do you suffer from heart disease, diabetes, Parkinson’s Alzheimer’s, macular degeneration, or age-related energy decline? ALA’s marketers say their product will help.  
Our take: Research has been accumulating about ALA, but so far not enough is known to recommend supplements. No one knows what dose and which form of ALA should be used for what ailment of condition.

Butterbur: Heading off migraines
Popular in Europe for many years, butterbur is extracted from the root of a shrub-like plant. It has earned some bona fides for preventing migraine headaches.
Our take: If you get migraines and conventional preventive strategies haven’t worked, butterbur may be worth a try. Petadolex is the safest option; you can’t be sure about other butterbur extracts, even if they make alkaloid-free claims. Don’t use butterbur if you are allergic to plants in the daisy family (including ragweed, marigolds, and chrysanthemums).

CLA: Can it promote weight loss?
Conjugated linoleic acid (CLA) occurs naturally in meat and dairy products. Supplements are manufactured from safflower or sunflower oil, and are typically promoted as a weight-loss aid.
Our take: Don’t take CLA supplements, especially if you have diabetes or liver disease. The risks outweigh the small potential benefits. CLA naturally found in food is fine – and may even be good for you. Full-fat dairy foods and meats from grass-fed animals are the richest food sources.

DHEA: Looking for the fountain of youth
The body’s most abundant steroid hormone (dehydroepiandrostgerone), DHEA is produced from wild yams and soybeans. If there’s something wrong with you, chances are DHEA has been touted as a treatment. Marketers claim it builds bone and muscle, reduces body fat, boosts sexual and athletic performance, improves cognition and heart health, and retards the effects of aging. No wonder people give it a try.
Our take: DHEA’s benefits are unproven and its potential risks are numerous. There are very few medical indications for it, and in those cases it should be taken under medical supervision. There is no logical reason why DHEA is not regulated as a drug like other sex hormones.

Echinacea: a daisy for colds
 Known also as purple coneflower, this supplement is sold in many varieties – tea, tablets, capsules, tinctures – and promoted as an immune system booster to treat – even prevent – colds.
Our take:  The claims about echinacea as a treatment for colds have yet to be supported by solid research. Because it may affect the immune system, some experts believe echinacea may worsen autoimmune disorders such as lupus, multiple sclerosis, and rheumatoid arthritis. If you have any of these conditions, it’s safest to avoid Echinacea – or at least talk with your health care provider before using it.

Fenugreek: Little seeds, big claims
Popular as a spice in many dishes, including curries (as is the spice turmeric, which is the source of the supplement curcumin, which I take), fenugreek is made from ground-up seeds. It’s rich in fiber and flavonoids, and is touted for a variety of uses, including managing diabetes and boosting libido.
Our take: Fenugreek has interesting properties that make it worth studying. But we recommend you limit its use to cooking and skip supplements, since their benefits are unproven and their long-term safety unknown. Keep in mind that if high-dose fenugreek does lower blood sugar, its effects could be unpredictable, which could be risky in people with diabetes.

Glucosamine: More than a placebo effect?
Our bodies manufacture glucosamine, which helps produce and maintain joint-cushioning cartilage. It’s the most popular supplement for osteoarthritis.
Our take: We recommend you forget about glucosamine – unless you are willing to pay $20 or more a month for what is probably a placebo effect. If you already take it and find it helps, continue with it, but consider stopping for a while to see if there’s a difference.

Huperazine A: Hup, hup, hooray?
Developed from a Chinese moss, this supplement seems to boost certain chemicals in the brain and is promoted as a treatment for dementia and Alzheimer’s.
Our take: Larger and larger studies are needed to confirm the current findings. But for people with dementia, huperazine A may be worth a try under medical supervision. Keep in mind there’s no evidence so far that the supplement boosts memory in healthy people or reduces the risk of dementia – which is also true, unfortunately, of all the many other supplements marketed for these purposes.

Iron: The Popeye mineral
This mineral – element “Fe” on the Periodic Table – is essential for life, carrying oxygen in the blood and regulating muscle function. While good diets provide more than adequate levels, iron deficiency can lead to dangerous anemia. Those most at risk include pregnant and premenopausal women, blood donors, vegans, long-distance runners, and people who take proton pump inhibitors for acid reflux or heartburn.
Our take: People at risk for iron deficiency should take a multivitamin / mineral containing iron. Doctors may advise a higher-dose iron supplement for certain conditions. But don’t take high-dose iron on your own – certainly not just because you are tired and think you may be anemic. And make sure you keep iron supplements out of the reach of kids: They are a leading cause of childhood poisoning deaths.

Jojoba: Does it do the job?
During periods of food scarcity, North American native peoples used the seeds of this shrub to suppress appetite. Now, it’s touted as a weight-loss aid.
Our take: Until well-designed clinical studies show that jojoba supplements are safe and effective for weight loss, don’t take it.

Kava-kava: Caution-caution ahead
This root from a tall shrub in the pepper family produces a mildly intoxicating brew with a long history of ceremonial and medicinal use on South Pacific islands. Its relaxing effect has been marketed to relieve anxiety, stress, and insomnia.
Our take: The risks of kava outweigh any benefits, especially if you have any kind of liver condition or take medication that can affect liver function. Other names kava may go by on supplement labels include kawa, ava, kew, tonga, yangona, and intoxicating pepper. If you suffer from ongoing anxiety or sleep problems, consult your health care provider, rather than take kava.

Lysine: Help for herpes?
Found in red meat, fish, and dairy products, lysine is an amino acid thought to suppress – or even prevent – the outbreak of cold sores caused by the herpes virus.
Our take: We do not recommend lysine. Its effect is unproven, and there are safe and effective supplements. Take them only when you feel a cold sore coming on, not continually.

Melatonin: For jet lag and better zzz’s
Called the “darkness” hormone because the pineal gland produces it at night, melatonin helps regulate circadian rhythm, the sleep / wake cycle. Light suppresses its secretion.
Our take: If you take melatonin, do so only occasionally and short term, since its long-term safety (and effectiveness) is unknown. Prolonged use may, for instance, undermine the body’s ability to produce its own melatonin. Like other sleeping pills, melatonin can produce a “hangover effect” and drowsiness the next day. If you have chronic insomnia or another sleep disorder, get medical advice.

Niacin: A vitamin for cholesterol control?
Niacin is one of the B vitamins. While statins are more effective than niacin in lowering “bad” LDL cholesterol, niacin has been promoted for raising “good” HDL cholesterol. The latest 2014 guidelines no longer recommend this vitamin across the board.
Our take: Statins remain the first-line choice because they lower LDL most and have been proven to prevent heart attacks and strokes. But if you can’t tolerate statins, you and your doctor may want to consider niacin, among other choices.

Omega-3s: Still fishing for answers
Marketers promote these fish-oil capsules to prevent heart attacks and strokes, to improve brain function, and to alleviate depression. After multivitamins, they are the most popular dietary supplement.
Our take: Recent studies on omega-3s have largely been disappointing, and the proposed cardiovascular benefits, in particular, now seem uncertain. A better bet is to get omega-3s from two or three servings of fatty fish a week, though the American Heart Association continues to advise people with heart disease or high triglycerides to continue taking supplements after consulting their doctors. Supplements have few, if any, side effects – and some of the proposed benefits may still pan out in future research.

Policosanol: A Cuban “statin”
Obtained mostly from sugarcane wax (hence the Cuba connection), this supplement can also be derived from beeswax, wheat germ, and rice bran. It is promoted as a treatment for high cholesterol.
Our take: We don’t recommend policosanol. Besides the questions about its efficacy, there’s little or no research about its long-term safety. In contrast, statin drugs have been well studied and are proven to be effective – and their side effects are known, so you can be monitored for them. What’s more, many generic statins are cheaper than many supplements.

Quercetin: The queen of antioxidants
Found in tea, red wine, fruits, and vegetables, this anti-oxidant, anti-inflammatory flavonoid is used to treat heart disease and diabetes. It is also touted to boost energy and athletic performance.
Our take: If you eat lots of fruits and vegetables, you’ll get a fair share of quercetin. Skip the supplement – the research, though sometimes encouraging, is still too limited. It’s uncertain how bio-available the quercetin in some supplements even is, compared to dietary quercetin. And it’s possible that quercetin works best in synergy with other flavonoids in foods, not as an isolated compound.

Resveratrol: Reserving judgment
Several decades ago, researchers identified this polyphenol as the ingredient in red wine that protected the French – noted consumers of delicious high-fat foods – from heart disease. Found naturally in grapes, peanuts, blueberries and other plant foods, it is promoted as a treatment for many things, including diabetes, cancer, Alzheimer’s, and cardiovascular disease.
Our take: While resveratrol is a promising compound, so far there have been no clinical trials on its effects on diseases and longevity in humans. Many studies are underway. The supplements appear to be safe, but their long-term effects are an open question. No one knows yet what doses are optimal or who would benefit. Until more is known, get your resveratrol from your diet.

St. John’s wort: Uplifting news
Scientists have studied this yellow-flowering weed for a long time. In Germany, doctors are required by law to write prescriptions for it, if they think their depressed patients will benefit. In America, people with mood issues simply buy the popular product over the counter.
Our take: Depression is a serious condition and you should not self-diagnose or self-medicate. Despite debate about the magnitude of the effect of prescription antidepressants, these drugs are still a first-choice treatment, especially for more severe depression. Still, St. John’s wort may be an option for mild to moderate depression, though if you are already taking a prescription antidepressant, you should not switch on your own or combine the two. A word of caution: The herb increases sun sensitivity when taken at high doeses or with sun-sensitizing drugs, and it can interfere with many drugs, including statins, the blood thinner warfarin, and oral contraceptives.

Tryptophan: To try or not to try
This amino acid from protein-rich food follows an interesting life cycle in the body; the brain first converts it into 5-HTP and then into the neurotransmitter serotonin, which affects sleep and mood. As a result, tryptophan is touted as a treatment for insomnia and depression.
Our take: Don’t take L-tryptophan (or closely related 5-HTP, also sold as a supplement). The pills may pose health risks, besides the risk of contamination. And a large intake of any single amino acid may interfere with the absorption or utilization of other amino acids.

Ubiquinone (CoQ10): Can you count on it?
A potent antioxidant with impressive anti-inflammatory properties, this compound supports the body’s mitochondria to produce energy. It’s been marketed as a treatment for a variety of illnesses and conditions, including heart disease, high blood pressure, Parkinson’s, diabetes, and cancer.
Our take: The claims for CoQ10 are overblown, and there’s no reason to take the supplement if you are healthy. No one knows how much to take or which formulation, if any, is best. Its long-term safety is still unknown. If you have heart disease, high blood pressure, or Parkinson’s disease and are considering CoQ10, discuss it with your health care provider first.

Valerian: An ancient sleep aid
This plant with pink or white flowers -- also called heliotrope – has been popular for millennia as a sleep aid. It has also been used in perfume making for centuries.
Our take: We don’t recommend valerian. It may not be more effective than a placebo, and you may not even be getting the “real thing” when you buy the supplements.

Wolfberry: berry big claims
Popular in Asia for centuries, these “super food” berries are hyped as promoters of good eyesight, agility, and longevity.
Our take: There's no evidence to support the use of wolfberry supplements to treat any medical conditions. No doubt, the berries are healthful, but there’s nothing magical about them to support their often-inflated prices (especially when sold as dried berries or in juices). All berries are nutricious and high in antioxidants.

AstaXanthin: Okay, so it doesn’t start with X
Several years ago, Dr. Oz’s endorsement  sent sales of this orange-red pigment soaring. It’s been touted as a treatment for heart disease, acid reflux, and joint problems. It’s also marketed to enhance muscle endurance, promote healthy eyes and skin, and retard the aging process.
Our take: There’s not enough solid evidence behind astaxanthin to recommend it. Though the supplements seem to be safe, that’s what we used to think about another carotenoid, beta carotene, which, at high doses, has been shown to increase lung cancer risk in smokers. Plus, unpleasant side effects – including unnatural orange-colored skin – are possible.

Yohimbe: Better sex in a bottle?
This centuries-old aphrodisiac comes from the bark of a West African tree. Yohimbe dilates blood vessels, increases blood flow, and may improve erections.
Our take: Because of safety concerns and the variability of the active ingredient, yohimbe should not be used.

Zinc: Nothing to sneeze at
The enzymes that regulate important functions – cell division, wound healing, immunitiy – need zinc. The popular mineral is widely used to treat colds, improve prostate health, and prevent some eye conditions, like macular degeneration.
Our take: If you are a vegan or are for any reason not consuming adequate zinc, consider taking a basic multi containing zinc (not a separate high-dose zinc supplement). If you want to try zinc lozenges when you have a cold, start as soon as you have symptoms. If you have AMD [age-related macular degeneration], talk to your eye doctor about the AREDS [Age-Related Eye Disease Study] formula. There’s no evidence that zinc or any supplement can prevent AMD or cataracts or otherwise protect healthy eyes.

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