A Fat Blocker Diet

As the Mayo Clinic notes, there are only two ways to lose weight: reduce your daily calorie allowance or burn more calories than you consume. To assist you, the weight loss industry provides a multitude of diet plans, pills, equipment and advice that vary with regard to safety, effectiveness and degree of personal involvement required. One such offering, available as a prescription or over-the-counter diet plan, is the fat blocker diet. Always consult your personal physician before starting a fat blocker diet.

Problem

An overabundance of fat in your diet puts both your weight and health at risk. At nine calories per gram, dietary fat has more than twice the calories per gram of carbohydrates and protein, both of which contain four calories per gram. In addition, saturated and trans fat increase your risk of developing serious medical conditions, such as high cholesterol and heart disease.

Types

A fat blocker diet can include either a drug called a lipase inhibitor or a natural substance called chitosan -- both prevent your digestive system from metabolizing most dietary fat.

In 1999, the U.S. Food and Drug Administration approved a lipase inhibiting drug called orlistat in 120 mg prescription strength for obesity management, followed by approval of a 60 mg over-the-counter strength version in 2007 for overweight, but not yet obese, individuals. According to the Mayo Clinic, orlistat disables the fat digesting enzyme lipase, preventing fat from breaking down and being absorbed by your intestines. The drug manufacturer GlaxoSmithKline manufactures and markets these drugs under the trade names Xenical and Alli.

Chitosan is a natural substance derived from the shells of sea crustaceans such as shrimp, lobster and crabs. According to Jamie Fritch at Vanderbilt University, chitosan prevents fat metabolism by binding to fat molecules and converting them into a form the human body cannot metabolize. Chitosan is available as an over-the-counter weight loss supplement under trade names such as Proactol and LipoSan.

Effectiveness

According to the Mayo Clinic, orlistat is moderately effective, with an average yearly weight loss of 5 to 7 lbs. greater than with diet and exercise alone using the prescription version and approximately 3 to 5 additional lbs. using the over-the-counter version. The Mayo Clinic declines to rate the effectiveness of products containing chitosan due to a lack of reliable evidence proving it really works.

Side Effects

The U.S. National Library of Medicine and National Institutes of Health list several possible side effects of both prescription and over-the-counter strength orlistat that include urgent bowel movements, gas, oily spotting, headache and stomach pain. To reduce or avoid these effects, you must decrease your consumption of dietary fat to no more than 30 percent of your daily calorie allowance and avoid foods with a fat content of greater than 30 percent.

Fritch states the products containing chitosan appear to have no known side effects at this time. However, because of a lack of scientific evidence relating to its use, Fritch urges you to use caution when using this fat blocker.

Always consult your own doctor to discuss if beginning a fat blocker diet is right for you.

Warning

If you choose to use orlistat, it is important to understand that both the prescription and over-the-counter strength versions involve a level of risk associated with fat-soluble vitamin absorption. The U.S. National Library of Medicine and National Institutes of Health state that in addition to preventing fat metabolism, orlistat also blocks absorption of the fat-soluble vitamins A, D, E, K and beta-carotene. To prevent your body from becoming deficient in these vitamins, both organizations recommend talking to your doctor before taking this drug, and taking a daily multivitamin containing these nutrients, two hours before or after taking an orlistat pill, or just before bedtime.