Subcutaneous and visceral fat carry very different health risks
Body fat is distributed across two fundamentally different zones that behave very differently metabolically. Subcutaneous fat sits directly under the skin and makes up most of total body fat for most people — it's the fat you can pinch between your fingers. Visceral fat sits deeper, packed around internal organs in the abdominal cavity, and is far more metabolically active than subcutaneous fat, functioning almost like an endocrine organ of its own.
Why location matters more than the total amount
Visceral fat cells release a different mix of inflammatory signaling molecules (cytokines like IL-6 and TNF-alpha) and free fatty acids directly into the portal vein, which feeds straight into the liver. That direct route is a major reason visceral fat is more tightly linked to insulin resistance, elevated triglycerides, and higher risk of cardiovascular disease and type 2 diabetes than subcutaneous fat at an equivalent overall body-fat percentage. Subcutaneous fat, while not metabolically inert, mostly stores energy without dumping nearly as much inflammatory signaling straight into liver circulation.
Why two people at the "same" body fat can have very different risk
This is why body-fat percentage alone is an incomplete health metric: two people at an identical 20% body fat can have meaningfully different cardiometabolic risk depending on how that fat splits between the visceral and subcutaneous compartments. Body-fat distribution is itself influenced by genetics, sex hormones (visceral fat tends to increase after menopause as estrogen drops, for instance), and age — not just diet and total energy balance.
A simple practical proxy
Since visceral fat isn't something you can pinch or measure at home, waist circumference relative to height is a reasonable, well-studied proxy: a waist-to-height ratio above roughly 0.5 (waist circumference more than half your height) is associated with meaningfully higher visceral fat and metabolic risk, even when the scale and overall body-fat percentage look unremarkable. It's a far more useful red flag than weight alone for this specific question.
Practical takeaway
Regular physical activity, and specifically strength training combined with cardio, is disproportionately effective at reducing visceral fat compared to subcutaneous fat — visceral fat responds fast to consistent exercise, sometimes producing a noticeable drop in waist circumference and health markers even before overall scale weight changes much. If the actual goal is reducing health risk rather than just moving a number on the scale, tracking waist circumference alongside weight is a better signal of progress.