Meta AnalysisHumann = 24 studies2013
Body weight loss reverts obesity-associated hypogonadotropic hypogonadism: a systematic review and meta-analysis.
Plain-language summary
This study set out to see how losing weight affects testosterone in men with obesity. It pooled 24 trials comparing low-calorie diets against bariatric surgery, measuring changes in total testosterone and other hormones. Both routes raised testosterone and surgery raised it more, 8.73 against 2.87 nmol/L. The more weight a man lost the more his testosterone rose, and the rise was larger in younger, non-diabetic men with a greater degree of obesity. A second meta-analysis in this library asks the same question of the same literature, so the two overlap rather than confirming each other independently.
Key findings
- Both low-calorie diets and bariatric surgery raised total testosterone levels.
- Bariatric surgery led to a bigger testosterone increase than diet.
- More weight loss meant more testosterone gain.
- Younger, non-diabetic men with severe obesity saw the biggest hormone improvements.
How to analyze the study yourself
- Study type
- Meta-analyses pool results from multiple studies to spot patterns, but they rely on the quality of the original studies and cannot prove cause and effect.
- Population
- Obese men, especially younger, non-diabetic men with severe obesity.
- Funding
- Not reported
- Takeaway
- This study found that losing weight raises testosterone in men with obesity, whether the weight came off through a low-calorie diet or through bariatric surgery, and that the more weight a man lost the more his testosterone rose. If you are carrying excess weight and your testosterone is low, losing weight is the first thing to change, and if surgery is on the table it is worth raising with your doctor.