Changes of Visceral Fat Mass are Allometrically Related to Total Body Fat Independent of Gender or Weight Loss Intervention

Abstract

Fat accumulation in the visceral adipose tissue (VAT) is believed to be particularly dangerous because it is highly correlated with cardiovascular and metabolic risk factors. We investigated whether or not some weight loss interventions are better than others at targeting the reduction of VAT. We hypothesized that changes of VAT are allometrically related to changes of total fat mass (FM), regardless of the type of intervention, as defined by the differential equation dVAT/dFM = k VAT/FM where k is a dimensionless constant. We performed a systematic search of the published literature for weight loss studies that measured FM changes along with VAT changes via MRI or CT imaging. 37 studies satisfied our search criteria, representing 1407 men and women using a variety of weight loss interventions. The allometric equation accurately modeled the data with k = 1.3 ± 0.1 and the model had an R^2=0.73. The same equation applied for both genders as well as a wide variety of weight loss interventions including bariatric surgery, caloric restriction with or without exercise, and exercise alone. We conclude that changes of VAT are primarily determined by FM changes as well as the initial VAT to FM ratio.