What is your opinion of the “Fat Blocker” tablets for weight loss? T.C.

Fat blockers have become quite popular over the past year and are being heavily promoted in print advertising and over the Internet. Two of the most common are chitosan, a shellfish derivative, and orlistat, a prescription drug sold under the name Xenical. Fat binds to the chitosan and is carried out of the body. Orlistat blocks the action of the digestive enzyme, lipase, which is required to break fats into absorbable fatty acids.

Their use is based upon the premise that, since fat contains twice as many calories as the same amount of protein or carbohydrate, elimination of fat from the diet will result in weight loss. This approach has been shown to be ineffective. People who decrease their fat intake tend to increase their intake of other foods, particularly sugars, as their bodies seek to replace needed nutrients.

I am strongly opposed to the use of fat blockers. Studies have shown that the average person in the United States is severely deficient in essential fatty acids, obtaining only about 10 % of the optimum amount each day. Use of fat blockers will further deplete the body’s supply of these nutrients that are necessary to control inflammation, regulate blood pressure, maintain healthy skin and nails, prevent small clots from forming in the bloodstream and produce chemicals needed for proper function of the brain and nervous system. In addition absorption of fat-soluble vitamins such as A, D & E will be compromised. –Dr. Peterson