Vital Information
By Dr. Beth Gruber, CarbSmart Contributor
Posted 3/21/2003
We've been talking about diet medications, and most recently, about Fen/phen. There seems to be a constant hunt for chemicals that will make one slim. Today we'll take a look at some of the herbal preparations for obesity that are vying for our consumer dollars.
Before looking at the specifics of herbal remedies, we have to face certain facts straight on: just because these products are called 'herbs' and are considered to be 'natural' does not necessarily mean they are safe and free from side effects. Just because a product comes from a natural source, rather than being concocted in a chemistry laboratory, does not necessarily mean it is safe. Consider that heroin, poisonous toad stools, and hemlock are all natural products.
Herbs Markets As Food Supplements
Herbal products are typically marketed as 'food supplements', and as such, may be mislabeled, or in some cases, adulterated. Some may contain ingredients or quantities of ingredients that are not listed on the label. For example, during an investigation by the Texas Department of Health a particular product was labeled "no side effects", and listed wild Chinese ginseng as the only ingredient. Laboratory analysis, however, found that tablets contained other ingredients, and taking the recommended dosage would result in the patient receiving about 11 times the usual recommended dosage for an over-the-counter drug used to aid in serious breathing difficulties.
Some herbal remedies are based on less-than-factual concepts. As I mentioned very briefly a few articles ago, kelp (a type of seaweed) as recommended to treat obesity is based on erroneous ideas. Kelp powder and tablets are offered with the idea that the iodine in the kelp will stimulate thyroid hormone production. However, such stimulation would only occur in persons with iodine deficiency, and iodine deficiency is very rare in developed countries since the widespread use of iodized salt.
Although many useful medicines have been derived from herbs and other plants, claims of therapeutic benefit with regard to obesity often overstate the existing scientific evidence even more than the claims for drug-type chemicals.
Many herbal products contain multiple ingredients and are promoted based on anecdotal claims of weight loss. One such product called a 'dieters herbal combination' contains chickweed herb, safflower florets, burdock root, parsley herb, kelp, papaya leaves, licorice root, fennel seeds, echinacea purpurea herb, black walnut hulls, and hawthorn berries. The customer is told that the remedy was formulated by a 'master herbalist', whatever that is. But, there is no actual proof that any of these herbs have anything whatsoever to do with weight loss.
The blossoms of wall germander (Teucrium chamaedrys) have long been used in folk medicine for obesity. Preparations include herbal teas, a medicinal liquor of germander mixed with other herbs, and capsules containing powdered germander alone or mixed with green tea.
Green tea is also touted as having an effect on weight loss. Green tea has generally been considered to be safe, but recently there has been some question about it contributing to liver toxicity. Since green tea can be taken in capsule form, it may be that those who had problems with it were merely taking too much.
A Carbohydrate Substance To Help Weight Loss?
Pectin, the same ingredient used in causing jam to gel, is not exactly an herbal product, but it does come from a vegetable source. Or more precisely, it comes from a fruit source. Pectin, a purified carbohydrate product obtained from the inner portion of the rind of citrus fruits, is a bulk-forming agent that absorbs water. It is often present in multi-ingredient preparations for the management of diarrhea, constipation, and also for obesity. It is said to decrease the rate of carbohydrate absorption by delaying the emptying of the stomach, thereby inducing a feeling of fullness. As far as I know, there have not been any low carbohydrate diet studies on the use of pectin as a weight loss aid. Before I would recommend it for use, I would want to see studies that show how much of the carbohydrate in the pectin is actually available for digestion.
Heat-Producing Herbs
Most of the herbal preparations urged for weight control fall into a category called thermogenic agents (thermo = heat; genic = creation, as in the word genesis). These herbs are said to cause the body to create more heat, and thereby cause a burn-off of more calories. This ought to result in weight loss, all other things being equal. These are the products that promise to speed up your metabolism.
Do they do it? Is metabolism sped up? Well, that depends on just what you mean by a speedier metabolism. There will be a drug-like effect in most people, similar that caused by a 'caffeine jag' or by a drug such as Speed. Some people who typically have a body temperature lower than normal report an actual rise in their body temperature while taking thermogenic agents.
The degree of heat production in the body is determined by the sympathetic nervous system. (The word 'sympathetic', as it relates to the nervous system, does not mean having sympathy or feeling sorry for someone. It refers to control of parts of the metabolic activities of the body, such as heart rate and blood flow.) Chemicals that act on the sympathetic system, be they drugs or herbs, are said to be sympathomimetic (sim-path-o-ma-METIC), which is to say that they mimic the effect of the body's own actions that stimulate the sympathetic nervous system.
A group of herbal products that fall into the group of thermogenic agents and sympathomimetic are sometimes known as The Stack. Next time we will discuss Stacking. Join me, won't you?
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