Metabolic and psychological response to 7-day fasting in obese patients with and without metabolic syndrome

Forsch Komplementmed. 2013;20(6):413-20. doi: 10.1159/000353672. Epub 2013 Jun 28.


Background: Extended modified fasting is a frequently practiced tradition in Europe. It is claimed to improve the cardiometabolic state and physical and psychological well-being by an evolutionary co-developed adaptation response. We aimed to investigate the cardiometabolic and psychological effects of a 7-day fast and differences of these responses between patients with or without metabolic syndrome (MetS).

Methods: We investigated 30 female subjects (49.0 ± 8.1 years, BMI 30.4 ± 6.7 kg/m(2)) with (n = 12) and without (n = 18) MetS. All subjects participated in a 7-day fast according to Buchinger with a nutritional energy intake of 300 kcal/day and stepwise reintroduction of solid food thereafter. Outcomes were assessed baseline and after fasting and included measures of metabolic and glucoregulatory control, adipokines as well as psychological well-being as assessed by Profile of Mood States (POMS) and Hospital Anxiety and Depression Scale (HADS).

Results: Mean weight decreased from 85.4 ± 18.8 kg to 79.7 ± 18.2 kg accompanied by systolic/diastolic blood pressure (BP) reduction of -16.2 mm Hg (95% CI: -9.1; -23.3 mm Hg) and -6.0 mm Hg (95% CI: -1.8; -10.3 mm Hg), each p < 0.001 and p = 0.005. Fasting led to marked decreases of levels of LDL-cholesterol, leptin, and insulin and increases of levels of adiponectin, leptin receptors, and resistin. Fasting-induced mood enhancement was reflected by decreased anxiety, depression, fatigue, and improved vigor. Patients with MetS showed some greater changes in B P, LDL-cholesterol, triglycerides, adiponectin, leptin, and sleep quality. Fasting was well-tolerated.

Conclusions: Our results point to marked beneficial responses to 7-day modified fasting and a potential role in the prevention of the MetS. Randomized trials with longer observation periods should test the clinical effectiveness of fasting in metabolic diseases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipokines / blood
  • Adult
  • Blood Glucose / metabolism
  • Blood Pressure / physiology
  • Cholesterol, LDL / blood
  • Comorbidity
  • Energy Metabolism / physiology
  • Fasting / physiology*
  • Fasting / psychology*
  • Female
  • Humans
  • Insulin / blood
  • Leptin / blood
  • Metabolic Syndrome / diet therapy*
  • Metabolic Syndrome / physiopathology
  • Metabolic Syndrome / psychology
  • Middle Aged
  • Obesity / diet therapy*
  • Obesity / physiopathology*
  • Obesity / psychology
  • Prospective Studies
  • Quality of Life / psychology
  • Receptors, Leptin / blood
  • Resistin / blood
  • Surveys and Questionnaires


  • Adipokines
  • Blood Glucose
  • Cholesterol, LDL
  • Insulin
  • Leptin
  • Receptors, Leptin
  • Resistin