Exploring the sense and nonsense of food and health

Leave a comment

The Dangers of Herbal Supplements

Folk medicine has used herbs for  centuries to treat and prevent disease. Today, they appear to be more popular than ever. It is estimated that about 1 in 6 Americans use herbs to treat or prevent illnesses. Herbal supplements are relatively inexpensive and easy to obtain – no prescription necessary.  Prescription medicines are tested for safety and efficacy and side effects are clearly available from the manufacturers.

Doses are regulated and standardized and physicians and pharmacists are trained to be aware of drug interactions that may occur that can cause dangerous sometimes fatal results. Herbal preparations have none of these safeguards. Here is what you need to know:

  • Many botanical components are toxic by themselves or in combination with other herbal components.
  • The FDA has issued warnings about ingredients such as comfrey, kava, and aristolochic acid.
    • Ephedra found in many weight loss preparations was found to cause heart attacks and strokes and was removed from the market in 2004. Ephedra extracts not containing ephedrine are not banned (according to Wikipedia) and can be found on the Internet.
  • Herbal supplements are subject to contamination of pesticides, microbes, metals and other toxins.
  • Doses are not thoroughly tested for purity and concentrations.
  • Some supplements should not be taken two to three weeks prior to surgery, e.g. St. John’s wort can prolong and intensity narcotic drug effects.
  • Herbal supplements should not be taken during pregnancy.
  • Do not give herbs to children.
  • Do not use herbs for long periods of time.
  • Do not fall for false health claims made by the manufacturer.

Source:   Smolin, Lori A., Grosvenor, Mary B. Nutrition: Science and Applications, Third Edition.



1 Comment

Buyers Beware: Herbal Products

English: Ginkgo leaves shown in their fall col...

English: Ginkgo leaves shown in their fall color, yellow. Français : Des feuilles de Ginkgo dans leur robe d’automne. Italiano: Foglie di Ginkgo biloba nella caratteristica colorazione autunnale. (Photo credit: Wikipedia)

The botanical definition of a herb is any seed-bearing plant that does not have a woody stem and dies down to the ground after flowering. Throughout history, herbs have been used to prevent and treat disease. Herbs were once considered a part of folklore but today they are more popular than ever. It is estimated that about one in six Americans uses herbs to treat illness or boost health. The six most popular herbal medicinal products in the U.S. today are: ginkgo biloba , St. John’s wort, ginseng, echinacea, saw palmetto, and kava.

Ginkgo Biloba is also called “maidenhair.” Today it is marketed to enhance memory and to treat some circulatory diseases. Supplements have not been found to reduce the incidence of dementia or protect against cognitive decline in older patients. However, there is some evidence that it may benefit mood and attention in healthy adults.

Side effects can include GI distress, headache, dizziness, and allergic skin reactions. It also can cause bleeding, when combined with warfarin or aspirin, elevated blood pressure when combined with a thiazide diuretic and coma when combined with the antidepressant trazodon

St. John’s Wort is claimed to promote mental well-being since it does contain low doses of the chemical found in Prozac. The results of clinical trials suggest that it is effective for the treatment of depression. Side effects include sensitivity to sunlight, anxiety, dry mouth, dizziness, GI symptoms, fatigue, headache, sexual dysfunction, interactions with antidepressants, birth control pills, digoxin, warfarin, and seizure-control drugs, antibiotics, immunosuppressants, and HIV medications.

Ginseng today is popular for its effects on cardiovascular health, the central nervous system, endocrine function, and sexual function,. However, controlled trials have been questionable when investigating other claims of immune system benefits, lowering of blood glucose and blood pressure. It may not be safe for those taking warfarin and has been found to interact with other medications such as estrogens, corticosteroids, antidepressants, and morphine. Side effects include diarrhea, headache, and insomnia.

Echinacea is known for its claim to treat colds, flu and infections. It is hypothesized to act as an immune system stimulant, but there is little evidence that it is beneficial in either preventing or treating the common cold. Very few side effects have been reported, but allergies are possible.

Saw Palmetto today is marketed to treat prostate enlargement and therefore improve urinary flow. There is some evidence of its effectiveness with mild to moderate improvement in urinary symptoms and flow measures; however, other trials report no improvement. There appears to be no drug interactions and only mild side effects of abdominal pain, decreased libido, headache, fatigue, nausea, and rhinitis.

Kava is marketed today to relieve stress and anxiety. A review of the effectiveness concluded that administration is effective in reducing anxiety. However, using this herb may not be the safest way to relieve stress. In 2002 the FDA issued a warning about kava since it may cause liver damage, including hepatitis, cirrhosis, and liver failure. It has been taken off the market in many European countries and in Canada, Australia, and Singapore.

Things to consider when taking any herbal product:

  • If you are taking other medications, consult your physician before taking herbs.
  • Do not take any herbal supplement for two weeks before surgery.
  • Do not take herbs if you are pregnant.
  • Do not give herbs to children in any form.
  • Do not assume herbal products are safe; many can be toxic.
  • Read the label ingredients and the list of precautions.
  • Start with low doses and immediately stop if side effects occur.
  • Do not take combinations of herbs.
  • Do not use herbs for long periods of time.

SOURCE: Smolin, Lori A, Grosvenor, Mary B. Nutrition: Science and Applicatons Third Edition. Wiley, 2013.

1 Comment

Are Herbal Supplements Safe?


Herbalism (Photo credit: Nomadic Lass)

Throughout history, healers have procured their remedies from the forest, garden and plant world.  Some “natural” products may be harmless while others are potentially toxic.  Other dangerous problems may arise when the dose is dangerous from improper doses not regulated to any great extent.  Herbal products may be mislabeled, adulterated by prescription drugs or contaminants (e.g. lead) or vary greatly in potency.

Overall, herbal products should be used with great caution and in consultation with a person’s primary physician.  Pregnant and nursing women, children under 2 years of age, those over 65, and anyone with a chronic disease (e.g. diabetes or heart disease) should not take herbal supplements unless their physician  consents to the practice and monitors them for potential complications.

Ginseng, for example, a common herbal supplement may cause hypertension, asthma attacks, irregular heartbeat, insomnia, headache, nervousness, GI tract upset, or reduced blood clotting. That’s quite a list of possible side effects especially when studies have not confirmed any benefit.

Even some herbal teas may be harmful.  Avoid any tea containing senna or comfrey.  Diarrhea and/or liver damage can occur depending on the dose.


Enhanced by Zemanta

Leave a comment

The “Crazy” World of Diet Supplements

Herbal supplements

Herbal supplements (Photo credit: Ano Lobb. @healthyrx)

A popular herbal supplement, Aristolochia, commonly sold as birthwort has recently been linked to kidney failure and kidney and bladder cancer.  This herb is commonly prescribed in Taiwan as part of traditional medicine and it was recently observed that nearly 12% of that country’s population suffers from chronic kidney disease.  Now the herb has been conclusively associated with these diseases through gene analysis.

This herb is not marketed in the U.S. since 1994 following FDA warnings. Since cancer may take years to develop, it still may be a causative substance even since it’s ban. In the case of supplements, manufacturers must ensure safety, efficacy, and proper labeling but this regulation does not appear to be enforced. Due to the passage of a supplement law, Congress may be allowing similar problems to occur in the U.S. by not requiring “natural” substances such as some herbs to be labeled for safety and effectiveness, as they should be.  In 2009, the U.S. Public Health Service added aristolochic acid to the list of human carcinogens. But how many other “birthworts” are out there?

Another supplement toxic alert involved only two young soldiers who died suddenly from heart attacks during workouts, having taken two products called “Jack3d” and “Oxyelite PRO  that contain the unregulated amphetamine- like dimethylamylamine, DMAA as the suspected cause. Since then, these two supplements were banned from military bases.  However, you can still buy these products at GNC and Vitamin Shoppe as well as bodybuilding websites.

Two-thirds of all Americans take some sort of dietary supplement and Americans spent about $11.8 billion on vitamins and minerals in 2010. While medications undergo safety and efficacy testing in order to receive approval by the FDA for release to market, dietary supplements do not. The 1994’s Hatch – Harkin Act, the Dietary Supplement Health and Education Act (DSHEA), was passed by Congress and subsequently released potentially harmful substances into the marketplace under the guise of “dietary supplements” many of which have not been evaluated for safety or effectiveness.

Supplements made from products available on the U.S. market prior to 1994 can be sold with no agency review, including a wide variety currently available. Sellers of products containing substances unavailable prior to 1994 need only advise the FDA and do not require approval to be sold

There have been approximately 51,000 new ingredients brought to market since DSHEA passed, of which about 0.3% or 170 out of 51,000 have documented safety tests.  Any claims made by the manufacturer is accompanied by “This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease”.

Weight Loss Products

Not only may some supplements may be downright dangerous, others such as some OTC weight loss products just plain don’t work.  Most of these products have never been tested for safety or efficacy.  Ephedra was the ingredient in many of these products that is now banned by the U.S. government since it caused serious health problems and in some cases deaths. Many supplements have been revised to include non-ephedra ingredients but are similar to ephedra and still may be dangerous.  From the Tufts Health & Nutrition Letter:

  • 5-hydroxytryptophan (5-HTP).. 5-HTP has not been proven to effectively promote weight loss and is under constant scrutiny for safety. In larger doses, 5-HTP may have a negative effect on the liver.
  • Chitosan (KITE-o-san). This dietary supplement is made from chitin, a starch found in the skeleton of shrimp, crab, and other shellfish making it not absorbed and binding to some fat in the diet. Several studies, however, found no more weight loss from Chitosan than from a placebo (sugar pill).
  • Chromium is thought to enhance the effect of insulin and therefore the breakdown of carbohydrates. It has been touted as a weight loss aid and a fat burner. Much of the evidence is inconclusive on chromium’s effect on weight loss. Several studies have failed to show any benefit in weight loss after taking this mineral.
  • Glucomannan. Made from the root of Amorphophallus Konjac, glucomannan is said to contribute to weight loss by delaying the absorption of glucose from the intestines. Small limited studies have shown glucomannan to be effective in decreasing body weight. This effect is believed to be due to a “feeling of fullness” which may be due to the swelling of the glucomannan in the gut once it has been exposed to liquids. However, esophageal obstruction has been reported in several people taking glucomannan. Glucomannan and glucomannan-containing products have been banned in several countries due to the high incidence of gastrointestinal obstruction.
  • Garcinia (hydroxycitric acid). An ingredient found in at least 14 weight loss supplements comes from a plant native to India and Southeast Asia. To date, the best available data show this product is not effective in weight loss.
  • Yerba Mate. Also known as Paraguay tea, yerba mate is a strong brain stimulant (the doses typically used mimic that of 100 to 200 mg of caffeine). The principle side effects reported are excessive stimulation and high blood pressure. It has not been proven to promote weight loss.
  • Guar Gum. Also known as guar, guar flour, and jaguar gum, guar gum is a dietary fiber obtained from the Indian cluster bean. It has been noted to decrease appetite by providing a “feeling of fullness.” However, like glucomannan, guar gum may cause obstruction of the esophagus. The water-retaining capacity of the gum permits it to swell to 10- to 20-fold and has led to gastrointestinal obstructions. Reviews of multiple studies show it has no effect on weight loss.

It is very possible that sometime in the future, some unregulated substance will kill a number of people or cause a dangerous health problem that could have been prevented by a more careful scrutiny of “dietary” supplements.  At the very least, more people are also affected by wasting their money on often expensive products that have never been shown to live up to their claims.  Buyers beware!

Enhanced by Zemanta