The formula, and why percent beats pounds
Percentage of body weight lost measures your change against where you started, so it compares fairly across people of different sizes. Losing 5 kg is 5% for a 100 kg person but 7% for a 70 kg person — same pounds, very different progress.
What each percentage means for health
| Loss | Health effect | From 200 lb |
|---|---|---|
| 1–3% | Minimal metabolic change | 2–6 lb |
| 3–5% | Better insulin sensitivity and blood lipids | 6–10 lb |
| 5–7% | CDC diabetes-prevention threshold | 10–14 lb |
| 5–10% | Lower blood pressure, cholesterol, blood sugar | 10–20 lb |
| 10–15% | Major cardiovascular improvement | 20–30 lb |
The Diabetes Prevention Program found that a 5–7% loss cut progression to type 2 diabetes by 58%. A modest percentage is where most of the health benefit already appears.
Reading the number correctly
- Pace matters as much as total. Around 1–2 lb a week is roughly 0.5–1% of body weight per week for a heavier person — sustainable, unlike a crash.
- Fast loss is not better. More than about 2 lb a week tends to shed muscle and water and rebounds.
- Track the trend, not the day. Water, salt and hormones swing daily weight by a pound or more; weigh once or twice a week and watch the weekly move.
- It is not BMI. This measures your change over time; BMI measures weight against height at a single moment.
Common questions
How do I calculate the percentage of body weight lost?
Subtract your current weight from your starting weight, divide by the starting weight, and multiply by 100. Losing 10 lb from a 200 lb start is 10 divided by 200 times 100, which is 5 percent.
What percentage of weight loss is healthy?
Health guidelines point to 5 to 10 percent over about six months, at a pace near 1 to 2 lb a week. Even a 3 to 5 percent loss improves blood sugar, blood pressure and cholesterol.
How much do I need to lose to reach 5 percent?
Multiply your starting weight by 0.05. For 200 lb that is 10 lb; for 90 kg it is 4.5 kg. The heavier your start, the more absolute weight a 5 percent loss represents.
