Research
Hormonal
Older pharmacotherapies (diethylpropion, orlistat, phentermine/topiramate) result in modest weight loss (3-7%) and are associated with significant side effects, making them less effective than newer GLP-1 agonists.
Older weight loss drugs like Orlistat (Xenical) can help you lose weight (average 15% in trials) but are less effective than newer GLP-1 injections. Orlistat works by blocking fat absorption. It must be taken with meals containing fat. Side effects like oily spotting are common if you eat too much fat. It is a second-line option.
GoodQualifiesHIGH confidence
The mean weight loss achieved with approved antiobesity medications is limited to 3%–7% after 6–12 months of treatment. Very few patients manage to achieve a body mass reduction of 10%–15% relative to placebo.
Why this rating
Supported by clinical trial data cited in the review.
Source
Review on obesity management: diet, exercise and pharmacotherapy
Katya Peri et al. · BMJ Public Health · 2024
DOI 10.1136/bmjph-2023-000246
narrative_reviewCited 7×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
More from this paper
- GLP-1 receptor agonists (semaglutide, tirzepatide) produce significantly greater weight loss (10-20%+) compared to other anti-obesity medications (3-7%) and placebo.Strong
- Combining a caloric deficit (500–750 kcal/day) with moderate-to-vigorous aerobic exercise (150–420 min/week) is significantly more effective for weight loss than either diet or exercise alone.Good
Related findings · Hormonal
- Initial treatment for type 2 diabetes should be a combination of metformin and either an SGLT-2 inhibitor or a GLP-1 receptor agonist to achieve cardiorenal protection, rather than monotherapy or older agents like sulfonylureas.Strong
- For patients with specific monogenic obesity syndromes (leptin deficiency, POMC/PCSK1/LEPR mutations), targeted pharmacotherapy (recombinant leptin or setmelanotide) is highly effective and should be prioritized, unlike in polygenic obesity.Strong
- Continued weekly administration of 2.4 mg subcutaneous semaglutide prevents weight regain and promotes further weight loss in adults with overweight or obesity, whereas switching to placebo results in significant weight regain.Strong
This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →