Rasvakerros

Rasvakerros, or fat layer, refers to a layer of adipose tissue located beneath the skin (subcutaneous fat) and around internal organs (visceral fat). It consists largely of white adipose tissue, made up of adipocytes that store energy in the form of triglycerides and release fatty acids during fasting. The rasvakerros serves several functions: it acts as an energy reserve, provides thermal insulation, offers mechanical cushioning, and functions as an endocrine organ by secreting adipokines such as leptin, adiponectin and inflammatory cytokines that influence appetite, insulin sensitivity, inflammation and metabolism.

Distribution varies with sex, age and genetics. Subcutaneous fat lies under the skin and can shape body contour, with regional differences such as more fat around hips and thighs in women and around the abdomen in men. Visceral fat, which surrounds internal organs, is more metabolically active and more closely linked to health risks. Excess visceral fat is associated with metabolic syndrome, insulin resistance, type 2 diabetes and cardiovascular disease, while subcutaneous fat can also contribute to metabolic outcomes depending on its distribution and quality.

Measurement and assessment include anthropometric indicators like body mass index and waist circumference, but imaging methods (MRI, CT) can separate subcutaneous and visceral fat for more detailed analysis. Management of excess rasvakerros typically involves lifestyle changes that reduce overall weight and improve metabolic health, such as balanced diet and regular physical activity, while maintaining lean body mass. Conversely, very low fat reserves can impair energy balance and thermoregulation.