Fat mass
Fat mass
Definition
Fat mass is the total weight of adipose tissue in your body. It includes essential fat (necessary for survival) and storage fat (energy reserve).
💡 Fat is NOT the enemy. It's necessary for hormones, brain, organ insulation. But excess harms health and performance.
The 2 types of fat
| Type | Function | Min % |
|---|---|---|
| Essential fat | Hormones, brain, organs | 3-5% (men), 10-13% (women) |
| Storage fat | Energy reserve | Variable |
The 2 fat distribution patterns
- Subcutaneous fat: under the skin (visible, "pinchable")
- Visceral fat: around organs (invisible, dangerous)
Visceral fat is far more risky for health (cardiovascular disease, diabetes type 2, chronic inflammation), even at apparently "normal" weight (TOFI: thin outside, fat inside).
Healthy fat mass values
| Category | Men | Women |
|---|---|---|
| Athlete | 6-13% | 14-20% |
| Fit | 14-17% | 21-24% |
| Healthy | 18-24% | 25-31% |
| Overweight | 25-29% | 32-37% |
| Obese | 30%+ | 38%+ |
⚠️ Going below 6% (men) or 14% (women) for extended periods causes hormonal disruption, low energy, immune drop.
How to lose fat without losing muscle
- ✅ Moderate caloric deficit: -300 to -500 kcal/day
- ✅ High protein: 2-2.5 g/kg to protect muscle
- ✅ Heavy strength training: signal to keep muscle
- ✅ Cardio (low to moderate): helps the deficit without burning muscle
- ✅ Quality sleep: lack of sleep favors fat retention
- ✅ Patience: 0.5-1% body fat per month is healthy and sustainable
Common mistakes
- ❌ Aggressive cut → loses fat AND muscle
- ❌ Cardio-only without strength training → muscle loss
- ❌ Pursuing ultra-low fat year-round (impossible)
- ❌ Trusting BMI alone (says nothing about composition)
- ❌ Skipping post-cut maintenance phase → yo-yo
Key takeaways
Fat mass is necessary in the right amount, harmful in excess. Aim for a healthy and sustainable range (10-17% men, 20-25% women), prioritize visceral fat reduction. Health first, aesthetics second. Slow and steady = success.
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