Wed, 23 Aug 2000

Just how safe are fiber supplements for losing weight?

Dear Clare,

I am tempted to use some of the fiber supplements on the market, especially the ones which claim they can be used to aid weight loss. But I have a few concerns:

1. What does natural fiber mean?

2. Are these products safer than using chemical laxatives, or something like Epsom salts?

3. Can they lead to dependence on them in the future, such as a sluggish bowel?


B. James


Dear Mr. James,

Your questions are interesting and you are wise to have a few concerns. Yes, fiber is a positive aid in weight loss, but I would like to recommend that you take fiber through real food instead of supplements.

When you are trying to slim, fiber can help by adding bulk to your meals at little caloric cost. It is great at making you feel "satisfied". For instance, incorporating plenty of fiber-rich foods in your diet such as vegetables, legumes, fruits and other unrefined carbohydrates, means you can fill your plate and not feel at all deprived. No hunger pangs and few calories.

1. With regard to your first question about "natural" fiber. Unfortunately, it does not actually mean anything!

Fiber supplements vary greatly and can contain a wide range of ingredients. For instance, glucomannan, which is a type of fiber from the konjac plant, or guar gum from the cluster bean or psyllium husks, which are from the seeds of the plantain plant. Other fibers include mixes of bran, inulin, citrus fiber concentrate, apple pectin and methylcellulose.

However, I suppose they are "natural" in a strict sense, as opposed to something like sawdust which is also used as an additional fiber in some weight loss products!

2. Fiber supplements, which are generally designed to make you feel full, can cause gastrointestinal upsets, esophagus problems and nutritional imbalances. Laxative abuse has no place in weight control.

By eating a healthy high-fiber diet, extra fiber should not be needed, unless advised by your doctor. Fiber should come from real foods because those foods have important antioxidant minerals, vitamins and other healthy components.

3. There is little evidence that taking fiber supplements help weight loss in the same way that high-fiber food does. Some studies show a short-term reduction in food consumed, but over time most people adapt to the added bulk in their digestive system and increase their food intake.

Nevertheless, a short-term trial of taking fiber supplements should not make you dependent on them.

Finally, do not be overly tempted by all the advertising. Why not try the really natural way first -- with food? It is healthier, it tastes better and is much cheaper, too! Good luck.

Clare E. Urwin.