Obesity is associated with an altered autonomic nervous system response to nutrient restriction

Objective Heart rate variability (HRV) reflects the balance of activities of sympathetic and parasympathetic components of the autonomic nervous system. We compared HRV parameters in response to a prolonged fast in obese versus normal weight humans. In addition, the effect of weight‐loss was evaluated in obese individuals. Design Intervention study. Patients The study subjects included 14 nondiabetic obese (12 females/2 males, aged 30 ± 3 years, Body Mass Index (BMI) 35·2 ± 1·2 kg/m2) and 12 lean subjects (10 females/2 males, aged 27 ± 3 years, BMI 23·3 ± 0·5 kg/m2). Measurements HRV was examined 75 min after standardized breakfast and after a 48‐h fast in 14 nondiabetic obese and 12 lean subjects. The postprandial measurement was repeated in 12 obese subjects after weight‐loss. Results In lean subjects, fasting decreased high‐frequency (HF) power by 43% (P