Decrease in visceral fat following diet-induced weight loss in upper body compared to lower body obese premenopausal...

Area of Science:

• Metabolic Health
• Obesity Research
• Cardiovascular Disease Prevention

Background:

• Obesity, particularly visceral adiposity, is linked to metabolic disturbances like insulin resistance, type 2 diabetes, dyslipidemia, and hypertension.
• Visceral fat accumulation poses a greater health risk for metabolic and cardiovascular complications compared to other fat depots.
• Obesity presents with distinct phenotypes, including upper body obesity (UBO) and lower body obesity (LBO), which may influence health risks and treatment responses.

Purpose of the Study:

• To investigate the differential effects of diet-induced weight loss on visceral fat mass and metabolic parameters in obese individuals with UBO and LBO phenotypes.
• To compare the reduction in visceral fat and improvements in metabolic markers between UBO and LBO women following a very-low calorie diet.

Main Methods:

• Obese subjects (UBO and LBO phenotypes) and controls underwent a liquid, very-low calorie diet intervention aiming for 15% body weight loss.
• Measurements included specific body fat assessments (MRI, BIA), anthropometrics, and fasting metabolic parameters before and after the weight loss intervention.
• Data were analyzed to compare changes in visceral fat mass and metabolic profiles between UBO and LBO groups post-intervention.

Main Results:

• Weight loss significantly decreased total, subcutaneous, and visceral fat in both UBO and LBO women.
• UBO women experienced a greater absolute reduction in visceral fat mass compared to LBO women (223+/-32 cm² vs 122+/-91 cm²; P=0.01).
• Visceral fat levels normalized in LBO women post-weight loss, while UBO women showed significant reductions in fasting glucose, total cholesterol, and LDL cholesterol.

Conclusions:

• The obese phenotype is maintained even after significant body weight loss.
• Upper body obese (UBO) women require a more substantial weight loss to normalize visceral fat depots and associated cardiovascular risk factors.
• Targeted weight loss strategies may be necessary to effectively manage visceral adiposity and reduce metabolic and cardiovascular risks in different obesity phenotypes.