Different response of body weight change according to ketonuria after fasting in the healthy obese.

The relationship between obesity and ketonuria is not well-established. We conducted a retrospective observational study to evaluate whether their body weight reduction response differed by the presence of ketonuria after fasting in the healthy obese. We used the data of 42 subjects, who had medical records of initial urinalysis at routine health check-up and follow-up urinalysis in the out-patient clinic, one week later. All subjects in the initial urinalysis showed no ketonuria. However, according to the follow-up urinalysis after three subsequent meals fasts, the patients were divided into a non-ketonuria group and ketonuria group. We compared the data of conventional low-calorie diet programs for 3 months for both groups. Significantly greater reduction of body weight (-8.6 ± 3.6 kg vs -1.1 ± 2.2 kg, P < 0.001), body mass index (-3.16 ± 1.25 kg/m(2) vs -0.43 ± 0.86 kg/m(2), P < 0.001) and waist circumference (-6.92 ± 1.22 vs -2.32 ± 1.01, P < 0.001) was observed in the ketonuria group compared to the non-ketonuria group. Fat mass and lean body mass were also more reduced in the ketonuria group. In addition, serum free fatty acid concentration after intervention in the ketonuria group showed significant more increment than in the non-ketonuria group. The presence of ketonuria after fasting may be a predicting factor of further body weight reduction.