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Does Alli Work?

Stella Mosko

Feb 11, 2008





Released in 2007 by manufacturer GlaxoSmithKline, Alli is the first FDA-approved non-prescription diet pill. Each Alli capsule contains a 60 mg. dose of orlistat, a drug that has been proven to prevent fat breakdown. Users are instructed to take this pill thrice daily with meals.


How does Alli work?

††††††††††† Orlistat, the active ingredient of Alli, works by binding to the bodyís lipases, enzymes in the gastrointestinal tract that digest fat compounds. This binding process prevents lipases from hydrolyzing triglycerides, a common type of lipid. As a result, approximately 25% of fat eaten will not be digested. Undigested fat cannot be absorbed and will be excreted via bowel movements.


Risks and side effects

††††††††††† The most common side effects of Alli include gas, oily spotting, loose as well as more frequent bowels, reduced bowel movement control, menstrual irregularity, headache, and anxiety. However, most of these symptoms can be alleviated if fat intake is reduced to 30% of daily calories.

††††††††††† By its mechanism of preventing fat digestion, Alli also prevents fat-soluble vitamins A, D, E, K, and beta-carotene, from being absorbed. To prevent deficiencies users should take a vitamin supplement.

††††††††††† Despite the majority of studies showing that the use of Alli is safe, users should at least be aware of a few objections. Roche, the pharmaceutical company for Xenical (orlistat pills double the strength of Alli, available only by prescription) conducted research revealing that the drug caused aberrant crypt foci (ACF) in the linings of rat colons. According to Dr. Sidney M. Wolfe of Public Citizens Health, there is a positive correlation between occurrences of ACF and colon cancer. Also, according to the American Journal of Medicine, orlistat presents a minor risk of liver toxicity.


Easy and effective weight loss?

††††††††††† GlaxoSmithKline strongly encourages users to reduce their fat ingestion to 30% of their daily calories in order to reduce Alliís unpleasant side effects. The average daily energy consumption for adults is 2,000 calories; therefore, if taken as recommended, Alli will only save users 150 calories per day. Considering that one pound of body fat is the equivalent of 3,500 calories, this amount seems insignificant.

††††††††††† Nonetheless, GlaxoSmithKline has performed studies that reflect Alliís effectiveness. Their results yielded 50% of users who lost at least 5% of their body weight and 20% who lost at least 10% of their body weight. However, Dr. Gareth Williams puts these results into perspective- he points out that these clinical studies are often conducted with the most motivated subjects, who are probably following the healthy advice in the Alli manuals in order to maximize the drugís effects.

††††††††††† A more indicative study was comprised of subjects who all made positive lifestyle changes, such as consuming healthier foods and increasing their exercise. After 4 years, the orlistat users lost an average of about 15 lbs, while the placebo group lost about 8 lbs.



††††††††††† If you follow the recommendations made by the manufacturers of Alli and reduce your percentage of daily fat intake, it is probable that you will lose weight without the aid of the pill. This likelihood is due to the fact that 1 gram of protein or carbohydrate provides 4 calories of energy, while 1 gram of fat provides 9.




Weight loss is unquestionably healthy for obese people, but the studies on orlistat debunk the false assumptions that Alli use will provide drastic benefits. Obese men are characterized as being 25% overweight, and the women as being 30% overweight; therefore, shedding a mere couple of pounds does not give way to major health rewards. A more effective and much less expensive solution to weight loss is to make lifestyle changes, which will also help to ensure that results are maintained.




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