Health
What Happens Biologically If You Try to Lose 20 Pounds in 3 Months?
The Answer
778 calorie daily deficit needed
The Full Picture
One pound of fat equals roughly 3,500 calories. To lose 20 pounds in 3 months (12 weeks) you need a 70,000-calorie deficit — 778 calories per day. For most people, this means cutting 400 calories and burning 400 via exercise daily. Aggressive but safe if done with whole foods and strength training to preserve muscle.
By the Numbers
Total calorie deficit needed70,000 calories
Daily deficit required778 calories
Recommended weekly loss1.5-2 lbs
Safer timeline4-5 months
Change the numbers
These numbers are just a scenario. Use our Calorie Calculator to see what your specific situation looks like.