Some fat-blockers may be ineffective and a few are even potentially dangerous
A lot of manufacturers market various over-the-counter diet drugs as “fat blockers” that can help you lose weight. Unfortunately, most of these supplements are ineffective and a few are even potentially dangerous. Prescription and over-the-counter strength orlistat is the only proven fat blocking drug, but both versions have some potentially unpleasant side effects.
If you take prescription-strength orlistat while dieting and exercising, you should lose at least 13 to 15 lbs each year. The drug, marketed as Xenical, literally blocks the fat from the food you eat so it passes out undigested through your bowel movements. However, Xenical does not give you a license to eat lots of fatty foods and lose weight. If you must eat a meal with more than about 15 g of fat, skip your dosage or risk embarrassing side effects such as uncontrollable bowel movements and oily gas.
You can buy over-the-counter orlistat or Alli if you are over the age of 18. Taking Alli in conjunction with a reasonable diet and exercise program should help you lose at least 11 to 13 lbs each year. However, a few users have claimed that Alli caused them severe liver injuries. FDA officials could not find a definite link between orlistat and liver injury, but advise patients to seek emergency medical help if they experience light-colored stools, dark-colored urine or jaundice.
People who do not have a gallbladder are advised not to take any form of orlistat or other fat blockers, because people without a gallbladder already have problems digesting fats. Diabetics and people with kidney problems need to think twice – or better yet speak to a doctor – before taking either Alli or Xenical.