The long-term influence of orlistat on dietary intake in obese subjects with components of metabolic syndrome

J Hum Nutr Diet. 2009 Feb;22(1):55-63. doi: 10.1111/j.1365-277X.2008.00920.x.


Background: Orlistat is a lipase inhibitor that reduces the intestinal absorption of fat and may enhance the effects of dietary and behavioural therapy on weight loss and maintenance. The present study examined the effect of orlistat on dietary intake, especially fat intake, during long-term weight maintenance.

Methods: Subjects comprised 44 men and women (aged 18-63 years; body mass index 37.5 +/- 4.3 kg m(-2)) included in the Scandinavian Multicenter study of Obese subjects with the metabolic syndrome, a 3-year clinical trial of orlistat or placebo following an 8-week, very low energy diet (VLED). Two months after the end of the trial when the use of orlistat was optional, 33 subjects remained in the study. A dietary interview based on a validated food frequency questionnaire was conducted before the VLED, after 1 year of treatment with orlistat or placebo and 2 months after the end of the trial.

Results: At 1 year, dietary intake did not differ between the orlistat and placebo group. Energy percent (E%) fat was reduced and E% carbohydrate was increased within both groups. Two months after the end of the trial, E% fat was 32.6% (SD 6.2%) in subjects that chose to take orlistat and 27.7% (SD 5.5%) in subjects not taking orlistat [between group difference -5.0% (95% confidence interval -9.2 to -0.7); P = 0.021].

Conclusions: The use of orlistat compared with placebo in a lifestyle modification programme does not appear to influence dietary intake. Subjects that chose to take orlistat after the end of the programme did not comply with dietary recommendations and this may hamper the effect of the drug.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Anti-Obesity Agents / adverse effects
  • Anti-Obesity Agents / therapeutic use*
  • Combined Modality Therapy
  • Diet, Reducing
  • Dietary Fats / administration & dosage*
  • Dietary Fats / metabolism
  • Energy Intake / physiology*
  • Female
  • Humans
  • Lactones / adverse effects
  • Lactones / therapeutic use*
  • Lipid Metabolism / drug effects
  • Male
  • Metabolic Syndrome
  • Middle Aged
  • Obesity / diet therapy
  • Obesity / drug therapy*
  • Orlistat
  • Patient Compliance
  • Treatment Outcome
  • Weight Loss
  • Young Adult


  • Anti-Obesity Agents
  • Dietary Fats
  • Lactones
  • Orlistat