Research

Energy balance

Orlistat, a lipase inhibitor, promotes modest weight loss (approx. 2-3 kg over 24 weeks) by blocking the absorption of dietary fat, but is associated with gastrointestinal side effects and potential fat-soluble vitamin deficiencies.

Orlistat is an older weight loss drug that works by blocking fat absorption. It leads to modest weight loss (around 2 kg over 6 months) and requires taking a capsule with each meal. Common side effects include oily stools and abdominal pain, which can be managed by keeping dietary fat low. You should also take a multivitamin at a different time of day to avoid nutrient deficiencies.

GoodSupportsHIGH confidence
Orlistat works by blocking gastric and pancreatic lipases... This results in a smaller amount of free fatty acids in the digestive tract being absorbed into the bloodstream... At the recommended dosage, orlistat decreases the dietary fat absorption by approximately 30%.
Patryk Gryszkiewicz et al. · Journal of Education Health and Sport · 2023

Why this rating

Cites randomized studies showing statistically significant reduction in body weight vs placebo.

Source

Review of upcoming and currently available anti-obesity drugs in Europe

Patryk Gryszkiewicz et al. · Journal of Education Health and Sport · 2023

DOI 10.12775/jehs.2023.30.01.005

narrative_reviewCited 2×
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DOI resolved against Crossref · corpus check 2026-06-10

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