Weight-loss products abound on the shelves of drugstores, health food stores, even supermarkets. They contain a range of ingredients. Some of these ingredients are utterly ineffective, and some are completely unsafe. Other ingredients do decrease appetite or increase fat loss, but their long-term safety has not been established.
What makes the products especially troublesome is that they are sold without prescription. Nor is it known if the weight that’s taken off comes back, as is the case with most diets.
The ingredients in these products, like the “fat blockers”, how do they work?
Over-the-counter fat blockers prevent a certain amount of dietary fat from being absorbed from the intestine. In controlled studies, some people took chitosan, a fat blocker made from the exoskeletons of shell fish, while others received a placebo, a blank pill that looked exactly the same. The studies showed that the chitosan did seem to have some effect on weight loss. In other clinical studies, large doses of chitosan caused a sharp drop in the blood levels of vitamin E, intensified the loss of calcium from bones, and resulted in the loss of other minerals.
Here are some of the ingredients in popular products that promise weight loss in a pill.
- Cassia (senna) and garcinia (camboge).
These act as laxatives and can be dangerous. People who have a history of intestinal obstruction and/or inflammatory intestinal disease should not take them.
A very expensive treatment for cellulite, cellasene is made of herbs, seed extracts, fish oil, soy lecithin. It is considered dangerous for women who are pregnant or lactating, people with thyroid conditions, and people on blood thinners.
- Chromium picolinate
It’s biological role is not well understood, although it appears to play a role in insulin metabolism. It is known to be toxic in large doses.
- Conjugated linoleic acid (CLA)
It is a mixture of polyunsaturated fatty acids that form in the intestines of cattle. In animals, CLA increased the percentage of muscle and decreased the percentage of fat. In human adults, CLA has no effect.
- Hawthorn, ginseng and ginkgo biloba
According to studies, these have no effect on weight loss.
- Hydroxycitric acid (HCA)
It is an extract of a tropical fruit, Garcinia cambogia, HCA can block the body’s fat metabolism by inhibiting the enzymes that turns citric acid to fat. It also has a laxative effect and has been shown to be toxic in animal studies. For weight loss in humans, HCA has no consistent effect.
- L-arginine and L-ornithine
These amino acids are said to help metabolize fat when taken with L-lysine before bedtime. No studies have shown that these amino acids have any measurable effect.
An amino-acid that plays a role in fat metabolism at the cellular level. Some overweight people may have low levels of this acid, but supplements have not been proven to affect weight loss.
- Phenylpropanalomine (PPL)
It suppresses appetite by increasing the brain level of a chemical called Dopamine, which is essential to the normal functioning of the central nervous system. You should not take PPL if you have heart disease, thyroid disease, kidney disease, or high blood pressure, or if you’re pregnant and breastfeeding.
Made in the body and found in some foods. Large doses of pyruvate can cause a slight fat decrease and slight muscle increase, but it has an insignificant effect on total weight loss.
- Willow (Salix)
Willow contains salicin, a naturally occurring salicylate. In lab studies, salicylate doubled the effect of ephedra but had no effect on fat loss when administered alone.