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, around internal organs in the abdominal cavity, and is far more metabolically active than subcutaneous fat.
Visceral fat is more tightly linked to inflammatory processes in the body and to a higher risk of cardiovascular disease and type 2 diabetes than subcutaneous fat at the same overall body-fat percentage. That's why two people with the same body-fat percentage can have very different health risk profiles — how fat is distributed between these two zones matters, not just the total amount.
A simple practical indicator is waist circumference relative to height: excess accumulation specifically around the abdomen likely points to a higher share of visceral fat, even if the scale and overall body-fat percentage look reasonable. Regular physical activity, especially combined with strength training, is effective specifically at reducing visceral fat, often even with a fairly small change on the scale.