Short-Term Low Calorie Diet Intervention Reduces Serum Advanced Glycation End Products in Healthy Overweight or Obese Adults

Abstract

Background: Obesity is a metabolic and cardiovascular risk factor. A low calorie diet (LCD) is one of the treatment modalities for weight loss. Serum advanced glycation end products (AGEs) are linked to increased atherogenicity and inflammation in diseases such as diabetes and renal failure. Obesity has an inflammatory component, but interestingly there are no studies on serum AGE levels in obesity or on the effects of LCD as a therapeutic measure on these markers of glycation. Aim: We hypothesized that weight loss by caloric restriction has a beneficial effect on serum AGE levels. We investigated the prospective effects of a sole LCD intervention for weight loss on serum AGEs in a cohort of overweight and non-morbidly obese but otherwise healthy subjects. Methods: A total of 37 Japanese subjects (30 females, 7 males, mean age 48.2 ± 9.3 years) with a mean BMI of 28.3 ± 3.2 participated in this study. During the intervention period of 2 months, they were placed on an LCD (Diet’s™; 5,023 kJ/day) with meal replacement every dinner. The following data were evaluated pre- and post-intervention: AGEs, BMI, waist circumference, blood pressure, serum glucose, cholesterol, triglycerides, HDL- and LDL- cholesterol. Results and Discussion: After the intervention, BMI levels were clearly reduced by 6.3% (p < 0.001), waist circumference by 5.7% (p < 0.002) and triglycerides by 11.9 % (p < 0.002). At baseline, AGEs levels were 63 ± 11 AU for obese subjects and 63 ± 14 for control subjects (not significant). After intervention, AGEs were reduced by 7.21% (range 0–35%, p < 0.001). The percent change in AGEs was significantly and positively correlated with that of triglycerides (r = 0.42, p < 0.009), waist circumference (r = 0.40, p < 0.011), and BMI (r = 0.42, p < 0.007). We show for the first time that serum AGEs can be reduced by an LCD intervention on weight loss, a change that correlates with the reduction in triglycerides. This may plausibly be a reflection of a reduction in glycation/lipoxidation due to the caloric restriction and its metabolic consequences, or it may be due to the decreased intake of food containing glycotoxins, or a combination of both.