The Effects of Short-Term Caloric Restriction on Cardiometabolic Health in Overweight/obese Men and Women: A Single-Arm Trial.

Overweight and obesity (Ow/Ob) is a risk factor for cardiometabolic disease. Caloric restriction (CR) have been investigated but little is known about the acute effects of CR and often such diets are not standardized. Thus, we aimed to assess the impact of a new standardized 3-day CR diet (590 kcal/d intake) on cardiometabolic health in weight-stable Ow/Ob individuals. In a single-arm design, 15 Ow/Ob men and women were assessed pre-post a 3-day standardized CR diet; specifically, body weight/composition (%body fat, visceral fat score (Vfs), blood pressure (BP), and vascular stiffness (VS), resting energy expenditure (REE), substrate utilization (respiratory quotient, RQ), and blood glucose/lipid profile). CR lowered body weight (93.1 +/- 15.2 to 90.67 +/- 14.4 kg, p < 0.001, d = 1.9), %fat (37.2 +/- 7.5 to 35.8 +/- 7.5%, p = 0.002, d = 1.1), and Vfs (13.1 +/- 4.5 to 12.2 +/- 3.9 a.u., p = 0.002, d = 1.1), but not body water (46.3 +/- 3.6 to 46.0 +/- 3.6%, p = 0.29). CR lowered VS (29.8 +/- 17.5 to 21.5 +/- 14.5%, p = 0.05, d = 0.6), but not BP (p > 0.05). Blood glucose (86 +/- 7 to 84 +/- 11 mg/dL, p = 0.33) and lipids (total cholesterol (196 +/- 49 to 203 +/- 54 mg/dL, p = 0.16) and TC/HDL (4.9 +/- 2.4 to 6.1 +/- 4.7, p = 0.13)) were unchanged. RQ decreased with CR (0.84 +/- 0.01 to 0.76 +/- 0.00, p < 0.001, d = 1.9), though REE was unchanged (p = 0.83). The 3-day CR diet significantly improved fat metabolism, body weight and composition, and vascular stiffness.