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Alli™—Weight Loss in a Pill?

Eryn Callihan

Oct 23, 2007



The 2003-2004 National Health and Nutrition Examination Survey (NHANES) suggest that 66 percent of the U.S adult population is either overweight or obese ( With rates of child, adolescent and adult obesity on the rise, obesity is quickly becoming a national health epidemic. Sedentary lifestyles and caloric, largely portioned meals, coupled with busy lives, and grueling schedules have led to this increase in obesity.

            Given today’s shocking obesity statistics, it is of little wonder Americans are quick to reach for weight loss products, fad diets, and quick fixes. In fact, according to the National Eating Disorder Center, 70 percent of women are dieting and 40 percent are continually gaining and losing weight ( Weight Watchers, Atkins, South Beach are all popularized diets that comprise a fraction of the multi billion dollar industry that thrives off of fat America. One such product, recently approved by the FDA, offers hope to overweight individuals. Approved February 7, 2007 under the brand name of Alli, this weight loss pill may help overweight and obese individuals reach their weight loss goals.


What Is Alli?


Alli is a marketed as a weight loss supplement designed to help overweight individuals lose those extra pounds in conjunction with a low-fat diet and increased exercise regime. Alli is a low dose version of Orlistat manufactured by GlaxoSmithKline, that is sold as an over the counter (OTC) pill for individuals 18 years and older.  Orlistat, previously marketed as Xenical, was approved by the FDA in 1999, and remains available in prescriptions in medications containing higher doses of Orlistat. (


How Does Alli Work?


Alli fills a special niche in weight loss products as it is designed to latch onto fat cells that are later excreted through stools.  Alli works by decreasing the absorption of fat in to the intestines therefore reducing the number of calories absorbed by the body. The exact mechanism of Alli is as follows:

1.      Fat cells enter the body through the digestion of food.

2.      The food is digested by the stomach and moved to the intestine, where Alligets to work.

3.       The intestine is lined with an enzyme, lipase, which is responsible for the break down of fats which are than stored for energy. Alli disables lipase from processing fat, which in turn must then be excreted from the body through bowel movements (


Alli™ essentially works as a lipase inhibitor in the intestines. According to a study by JW Anderson of the Department of Internal Medicine at the University of Kentucky, Alli™ blocks the absorption of approximately 25% of ingested fat and has an estimated 85% of the efficacy of the 120-mg dose for weight loss. Furthermore, because of gastrointestinal side effects, this same study found the 60 mg dose, the standard OTC dosage, is better tolerated than 120mg dosage of Alli™ (Anderson, JW). Beyond weight loss, Alli™ has also been found to contribute to decreased values of LDL’s in the blood serum ( LDL’s, known as low-density lipoproteins, are known to increase the risk of arteriosclerosis, causing harmful blockage in arteries and blood vessels. ( Often LDL is referred to as the “bad Cholesterol” due to its adverse effects on health.


Is Alli the Miracle Weight Loss Drug?


While on surface level Alli™ may seem like the miracle, weight-loss drug many Americans have been hoping for, it is crucial that the individual is knowledgeable of side effects, drug reactions and know health risk Alli™ may produce. Like most drugs on the market, Alli™ too shares a large array of adverse and fairly unpleasant side effects.


Absorption of Fat Soluble Vitamins and Essential Fatty Acids


One of the detrimental side effects of Alli™, is this drugs role in prohibiting the absorption of fat soluble vitamins. Because Alli™ blocks the absorption of fat in the intestines, it also inhibits the bodies ability to absorb fat soluble vitamins, such as vitamin D, A, and E. Benefits of vitamin D, A, and E include, but are not limited to: maintenance of skin, mucous membranes, bones and teeth, vision, retention of calcium and bone and red blood cell formation. ( Furthermore, Alli™ may inhibit the absorption of essential fatty acids such as omega- 3and 6 fatty acids.  Omega 3 fatty acids are crucial to maintaining a health body. Omega 3’s are poly-unsaturated fats that studies have shown decrease triglycerides in the system, increase HDL cholesterol, and help in preventing heart disease. Due to Allis’™ fat inhibiting mechanism, it is  disconcerting that both fat soluble vitamins and essential fatty acids may be excluded for those using Alli™ ( Mike Adams a holistic nutritionist suggests the market of Alli™, in light of this information, is a detriment to public health, and merely a money maker for pharmaceutical companies. He states,


 "I question whether the FDA has seriously looked at the risks of further  malnutrition of fat-soluble vitamins and essential fatty acids. Maybe this decision  was based on the incorrect but widely held belief in conventional medicine that  diet really has no relationship to health… [these] risks are widespread nutritional  deficiencies that exacerbate existing deficiencies and can lead to serious  degenerative disease ("


In a two year double blind study of 743 obese patients, 5.8% of the participants given 120mg dosages of Orlistat had “abnormally low concentrations of alpha carotene [a derivative of vitamin A], vitamin D, or Vitamin E” ( In addition to a decreased absorption of both fat soluble vitamins and essential fatty acids, Alli™ is known to cause rather unpleasant physical side effects.


The Unpleasant Side Effects of Alli


In researching the reviews of Alli™, the repeated complaint was the gastrointestinal disruptions Alli™ causes. As clearly stated by the FDA and the Alli™ official website (, it is recommended to take Alli™ only when eating a low-calorie, low-fat diet. Alli™ excretes fat through stools, therefore eating a diet high in fat exacerbate this process, resulting in more frequent bowel movements.  It is recommended that individuals using Alli™ eat no more than 15 grams of fat with each of their three daily meals ( As seen in the previously mentioned double blind study of 743 obese patients, urgent bowel movements, gas, and oily spotted stools are nasty side effects of Orlistat. In essence, Allis’™ threat to create sudden, uncontrollable bowel movements is enough to scare any individual into choosing lower fat foods. (

Furthermore, early studies of patients taking Orlistat found a distinct causal relationship between Orlistat and hypertension. This same study completed by Matty Persson and Sigurd Vitols stated that by 2000, there were 13 overall cases of hypertension associated with Orlistat that have been reported to the manufacturer. (


The Bottom Line


Studies show that taking Alli™ when obese or overweight helps in losing weight, particularly in the first six months.  One study performed by James Anderson, head of the UK College of Medicine Metabolic Research Group, and his colleagues, found a positive correlation between overweight patients taking 60mg dosage of Alli, and a subsequent weight loss. According to the study:


Participants took either orlistat or a placebo three times daily with meals for 16      weeks. Results of that study showed those taking OTC-strength orlistat did lose    more weight than those taking the placebo” (“Weight Loss; Does OTC diet pill Alli live up to its name?”).


Sole knowledge however of Allis' weight loss benefit is not sufficient when deciding whether to use Alli. Having reviewed much of the information on Alli, I would recommend reading and researching Alli before trying it. The adverse side effects of Alli coupled with the bodies decreased ability to absorb essential nutrients, is alarming and should be taken into serious consideration. As with any drug, the perceived benefits must out way the known health risks, and unwanted side effects. Knowledge is power so be informed before using Alli.




Works Cited

Anderson, JW. Orlistat for the management of overweight individuals and  obesity: a  review of potential for the 60-mg, over-the-counter dosage.        Expert Opin     Pharmacother. 2007 Aug;8(11):1733-42.


Weight Loss; Does OTC diet pill Alli live up to its name? (2007, July). Medical Letter on  the CDC & FDA,12.  Retrieved September 23, 2007, from Health   Module database. (Document ID: 1291748631).





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