BMI 45: What It Means and What to Do
A body mass index of 45 places you in the Obese Class III category according to WHO and CDC standards. The average BMI for US adults is 29.8 (men: 29.4, women: 30.1).
BMI Scale Position
Your BMI: 45 — Very high risk; associated with significantly reduced life expectancy
BMI Category
Obese Class III
Healthy BMI Range
18.5–24.9
BMI to Lose to Reach Normal
20.1 BMI
Approx. Lbs to Lose (5ft9 ref)
~156 lbs
Weight Loss Timeline to Reach Normal BMI (5'9" reference)
A BMI of 45 at 5'9" corresponds to approximately 305 lbs. Reaching the midpoint of the normal range (BMI 22) at this height requires losing roughly 156 lbs.
−500 cal/day
156 weeks
36.0 months
1.00 lbs/week
−750 cal/day
104 weeks
24.0 months
1.50 lbs/week
FDA recommendation: 1–2 lbs/week. Deficits over 1,000 cal/day require medical supervision. Actual height and weight vary; use the BMI Calculator for your exact numbers.