What Is Alli?The Alli diet pill (pronounced AL-lye) is an over-the-counter version of a medication called Orlistat or Xenical, previously available only by prescription. It is the first over-the-counter weight-loss medication to be approved by the FDA. It costs about $1.50 to $2 per day (3 pills per day).
How Does Alli Work?Alli blocks part of the fat in the food eaten in a meal. That fat is eliminated in the feces instead of being absorbed to be used by the body. The literature says it blocks about 25% of the fat eaten in a meal. However, the real secret to how it works is that people get uncomfortable effects if they eat more fat than recommended.
How Much Weight Is Lost on Alli?Alli was tested on a group of mildly to moderately overweight people as part of a diet and exercise plan. Those taking Alli lost an average of 10 1/2 pounds over the 16 weeks of the study, as opposed to an average of little less than 7 pounds for the placebo group. The advertising literature says that you can lose 50% more with Alli than you would by diet alone -- they get this figure from that research. But remember that that number is an average, and the study only lasted 16 weeks.
What Are Some of the Problems With Alli?
"Treatment Effects" - Note that these are not called "side effects," because they are more or less the intended effects of taking Alli. Basically, if you eat too much fat at a meal, you will be pretty uncomfortable. The exact amount of fat that will trigger these effects varies per person, but it is recommended to eat no more than 15 grams of fat per meal. Treatment effects include:
- gas with oily spotting (it is advised not to "pass gas" unless you are on the toilet)
- loose stools
- more frequent stools that may be hard to control ( The patient information states, "Until you have a sense of any treatment effects, it's probably a smart idea to wear dark pants, and bring a change of clothes with you to work.")
Lack of absorption of vitamins - Fat-soluble vitamins can be flushed out along with the fat, so it is advised to take supplements of vitamins A, D, E, and K, and beta-carotene. What is not addressed is that many phytonutrients also need fat to be absorbed, so people taking Alli may be getting less of these valuable substances as well.
What Doesn't Alli Do?It doesn't control appetite, increase metabolism, or block any calories other than fat. It doesn't change blood glucose or blood insulin.
What Diet is Recommended with Alli?It's a little hard to tell, beyond it being low in fat and calories. They are pretty cagey about not revealing the recommended diet before buying the product. Certainly they don't advise more than about 15 grams of fat per meal. Snacks should be low in fat. Calories are in the range of 1200 to 1800, depending on the person. The web site doesn't tell how much carbohydrate or protein is advised.
How Much Fat Is 15 Grams?It is difficult to get any nutrient-rich diet to be lower than 10% fat -- this is with no "extra" fat or "fatty" foods (such as the dark meat of chicken) at all. For a 1,500-calorie diet, that's about 17 grams of fat. This means that any added fat would need to be limited to 10 grams per meal. This is the amount of fat in 2 teaspoons of olive oil, 1 oz of cheese, or 2 tablespoons raw almonds. Or you could have a 3 oz hamburger (15 grams fat) and some almost fat-free vegetables or other truly fat-free food.
Why Should Alli Not Be Used With a Low-Carb Diet?The weight loss effect of Alli operates in a totally different way than that of low-carb diets. There are several reasons why those following a low-carb way of eating should not take Alli, including:
1) Low-carb diets should not be low in fat - You have to get your calories from somewhere, and if it's not from carbs, some of it is going to be from fat.
2) Low-carb diets work partly because protein and fat are more satisfying than carbohydrate. Therefore, people on low-carb diets naturally eat fewer calories. Alli limits calories by limiting fat.
3) Low-carb diets also work because they lower blood glucose and insulin. Alli does not help with this. In fact, it could conceivably raise blood glucose, to the extent that people replace fat with carbohydrates.
If you are still interested in trying Alli after reading this article, be sure to read this patient information first. It will inform you about whether you should consult your health care provider, drug interactions, side effects, and more.
GlaxoSmithKline Web site, accessed July 2007
Anderson, JW, Schwartz, SM, Hauptman, J, et al. "Low-dose orlistat effects on body weight of mildly to moderately overweight individuals: a 16 week, double-blind, placebo-controlled trial." Annals of Pharmacotherapy. 40.10 (2006):1717-23.
Brown, Melody, Ferruzzi, Mario Nguyen, Minhthy et al. "Carotenoid bioavailability is higher from salads ingested with full-fat than with fat-reduced salad dressings as measured with electrochemical detection." American Journal of Clinical Nutrition. 80.2 (2004):396-403