The effect of low-carbohydrate ketogenic diet in the management of obesity compared with low caloric, low-fat diet

Clin Nutr ESPEN. 2022 Jun:49:522-528. doi: 10.1016/j.clnesp.2022.02.110. Epub 2022 Feb 24.

Abstract

Background & aims: Previous studies comparing low-carbohydrate ketogenic diet (LCKD) and low caloric fat low diets (LCLF) in obesity management are still controversial. This study evaluated the effect of LCKD in weight reduction compared to the LCLF diet among Omani obese adults.

Methods: This prospective cohort study was conducted at the National Diabetes and Endocrine Centre (NDEC), Royal Hospital, Muscat, Oman, between 2015 and 2017. We included 200 (100 in each group) obese patient with Body Mass Index (BMI) more than 30kg/m2, who attended the outpatient department and met the inclusion criteria were enrolled in the study for six months follow-up. Anthropometric, biochemical and clinical data was gathered before starting the diet. Follow-up outcomes included reduction in weight, fat mass and visceral fat, lipid profile and HbA1c. Data were analysed using SPSS-24.

Results: The LCKD group showed a significant reduction of 13.0 kg (95% CI: 11.0-15.1) in body weight compared to 4.7 kg (95% CI: 3.4-5.9) in the LCLF group with p-value<0.001. LCKD group showed a significant reduction of 4.0% (95% CI: 3.3-4.7) in fat mass, compared to 1.4% (95% CI: 0.83-1.9) in the LCLF group with p-value<0.001. In addition, LCKD group showed a significant reduction of 2.5L (95% CI: 2.0-2.9, P < 0.001) in visceral fat compared to 1.2L (95% CI: 0.86-1.56) P < 0.001) in the LCLF group with p-value<0.001. Combined with significant reduction in HbA1c with 0.69% (95% CI: 0.5-0.89, P < 0.001) in LCKD and a reduction of 0.74% (95% CI: 0.47-1.2, P < 0.001) in LCLF. Furthermore, this diet has not increased lipid profile with a mean reduction of 0.19 mmol/L (95% CI: 0.003-0.37, P < 0.001) in total cholesterol and mean change of 0.04 mmol/L (95% CI: 0.12-0.21) in LDL level. In addition, it has not increased uric acid with a mean reduction of 20.8 umol/L (95% CI: 4.8-36.7), (P = 0.01).

Conclusion: LCKD seems superior to LCLF in weight, fat mass and visceral fat reduction. In addition, this diet does not increase serum cholesterol and uric acid, which encourage the use of this diet in obesity management.

Keywords: Fat mass; Low calorie low fat; Low carb ketogenic diet; Muscle mass; Obesity; Visceral fat.

MeSH terms

  • Adult
  • Cholesterol
  • Diet, Fat-Restricted*
  • Diet, Ketogenic*
  • Glycated Hemoglobin
  • Humans
  • Lipids
  • Obesity
  • Prospective Studies
  • Uric Acid

Substances

  • Glycated Hemoglobin A
  • Lipids
  • Uric Acid
  • Cholesterol