Healthy Lean Mass Percentage by Age
What is normal at 20, 40 and 60, and what to aim for.
By Menang7, owner of LeanMassCalculator.com
Lean Mass vs Muscle Mass →Lean mass percentage tends to fall with age as muscle shrinks and fat rises. These ranges are general guides, not diagnoses.
Your lean mass percentage is the share of your body weight that is not fat: muscle, bone, organs and water. It is simply 100 minus your body fat percentage.
Lean mass % by age
| Age | Men: lean mass | Men: body fat | Women: lean mass | Women: body fat |
|---|---|---|---|---|
| 20–29 | 80–88% | 12–20% | 72–80% | 20–28% |
| 30–39 | 78–86% | 14–22% | 70–78% | 22–30% |
| 40–49 | 76–84% | 16–24% | 68–76% | 24–32% |
| 50–59 | 74–82% | 18–26% | 66–74% | 26–34% |
| 60+ | 72–80% | 20–28% | 64–72% | 28–36% |
The ranges at a glance
Lean Body Mass vs Muscle Mass
Lean mass is more than muscle. Learn what each one measures and which is better to track as you age.
Check your range
Why women have a lower lean percentage
Women naturally carry more essential body fat, linked to hormones and reproduction, so a healthy range for women sits below that for men.
Staying in the healthy range
Frequently asked questions
Roughly 76–86% for men and 68–78% for women in midlife.
Higher fat with low muscle is linked to metabolic risk. Talk to a doctor if you are concerned.
Muscle tends to shrink and fat tends to rise as we get older, especially without resistance training and enough protein.
Subtract your body fat percentage from 100. For example, 22% body fat means 78% lean mass. Use a DXA scan, smart scale or skinfold test, or the Body Fat Calculator for an estimate.
No. Lean mass also includes bone, organs and water. Muscle is roughly half of it.
Related
About Menang7, the author
This article is part of LeanMassCalculator.com, developed, owned and maintained by Menang7. For questions about these ranges or the calculators, Menang7 is the person to look for.
For personal medical or nutrition decisions, please also speak with a doctor or registered dietitian.