Visceral fat
Deep fat stored around the internal organs (liver, pancreas, intestines), metabolically active and far more dangerous to health than subcutaneous fat.
The body stores fat in two places:
- Subcutaneous fat: under the skin (thighs, hips, arms), relatively inert and less harmful
- Visceral fat: deep inside, wrapping around the organs of the abdomen, and metabolically dangerous
The original angle (a toxic endocrine organ): the major discovery: visceral fat is NOT a simple inert store, it is an active endocrine organ that constantly secretes molecules:
- Pro-inflammatory cytokines (TNF-α, IL-6) → chronic low-grade inflammation
- Molecules that worsen insulin resistance
- Free fatty acids that flood the liver (→ fatty liver)
It is therefore at the heart of metabolic syndrome, type 2 diabetes and cardiovascular risk. Visceral fat “communicates” harmfully with the whole body.
The TOFI phenotype (thin outside, fat inside): a major counter-intuitive point: you can be a normal weight, even slim, and still have too much visceral fat (“Thin Outside, Fat Inside”). These “metabolically obese normal-weight” people have hidden risks that a normal BMI masks. Conversely, some overweight people who mostly have subcutaneous fat are metabolically healthier (“metabolically healthy obesity”).
This is why waist circumference is a much better indicator than weight or BMI (>94 cm for men, >80 cm for women is a warning sign in Europe).
The good news (it melts first): visceral fat is the first to be mobilised with exercise and a better diet. A few kilos lost reduce visceral fat disproportionately and improve all metabolic markers, even before any visible weight loss.
The levers:
- Physical activity (above all; very effective on visceral fat, even without weight loss)
- Cut back on sugars and fructose (which feed the liver and visceral fat)
- Sleep and stress management (cortisol promotes visceral fat storage)
- A diet rich in fibre and protein