Introduction: Obesity is often accompanied by a number of complications including diabetes mellitus and cardiovascular diseases. Elevated blood pressure and lipids, as well as deterioration of glucoregulation are attributed, as the most significant factors, to development of diabetes mellitus and cardiovascular complications in obese patients.
Objective: The aim of our study was to evaluate the effects of a fasting diet on blood pressure, lipid profile and glucoregulatory parameters.
Method: We included 110 patients (33 male and 77 female; mean age 35 +/- 1 years, body weight 131.7 +/- 2.6 kg, body mass index 45.4 +/- 0.8 kg/m2) who were hospitalized for three weeks for the treatment of extreme obesity with the fasting diet. At the beginning, during, and at the end of this period, we evaluated changes in blood pressure, lipid profile, as well as parameters of glucoregulation including glycaemia, insulinaemia, and insulin sensitivity by HOMA. Oral glucose tolerance test (OGTT) was performed in all patients at the beginning and at the end of the fasting diet.
Results: During the fasting diet, the body weight decreased from 131.7 +/- 2.6 kg to 117.7 +/- 2.4 kg (p < 0.001), the body mass index decreased from 45.4 +/- 0.8 kg/m2 to 40.8 +/- 0.8 kg/m2 (p < 0.001), and both systolic and diastolic blood pressure significantly declined (143 +/- 2 vs. 132 +/- 2 mm Hg, p < 0.001; 92 +/- 2 vs. 85 +/- 2 mm Hg, p < 0.001). In addition, the fasting diet produced a significant decrease in total cholesterol, LDL cholesterol, triglycerides, as well as basal glycaemia and insulinaemia (p < 0.001) Before the fasting diet, OGTT was normal in 76% of patients, whereas 21% of patients showed glucose intolerance, and 4% of patients diabetes mellitus. After the fasting diet, OGTT was normal in 88% of patients, whereas 12% of patients still had signs of glucose intolerance (p < 0.05). In addition, insulin resistance significantly (p < 0.05) increased from 54 +/- 6% to 89 +/- 13% after the fasting diet.
Conclusion: The three-week fasting diet in extremely obese patients produced a significant decrease and normalization of blood pressure, decrease in lipids, and improvement in glucoregulation including the increase in insulin sensitivity.