Weight loss of 15% or more from maximum body weight is associated with increased risk of death from all causes among overweight men and among women regardless of maximum BMI.
“Associate”, here, appears to mean “correlate”. The 15% piqued my interest because it echoed this bit* from The Practical Guide: Identification, Evaluation, and Treatment of Overweight and Obesity in Adults, from the US National Institutes of Health (NIH) guidelines on “obesity treatment”:
Obese individuals typically want to lose 2 to 3 times the 8 to 15 percent often observed and are disappointed when they do not. (p32)**
Correlation does not necessarily mean causation, but this leads me to wonder whether, on average, a more than 15% loss requires more extensive changes to diet and exercise, that in turn can result in more muscle loss and other damage? Nobody knows. It’s not clear whether the correlation is a strong one (3000% more likely?) or a weak one (100% more likely?) or if it will actually mean anything in the end. But I do think we should focus more on health than on weight.
I also note they did find one group where weight loss reduced risk of cardiovascular disease: obese men who lost between 5% and 15% of their max weight. I also note that reducing risk of cardiovascular disease can be done by increasing exercise and other such changes, without focusing on weight loss.
*Posted about here.
**For convenience, I’m using PDF page numbers, which can be entered into the PDF viewer to go directly to the page in question. These do not map to the printed page numbering.