How long is it reasonable to lose 20 pounds?

A reasonable timeframe to lose 20 pounds is 10-20 weeks (about 2.5 to 5 months). This allows for safe weight loss of 1-2 pounds per week. This pace is sustainable, helps preserve muscle mass, reduces health risks, and makes it more likely you'll keep the weight off long-term. Slower weight loss also allows time to build healthy habits that last.