Castellana · Reviews in endocrine & metabolic disorders 2020 · systematic review and meta-analysis · n=12 studies

Efficacy and safety of very low calorie ketogenic diet (VLCKD) in patients with overweight and obesity: A systematic review and meta-analysis.

Cited 261 times in the scientific literature.

Level 1 - systematic review of randomized trials

Systematic review and meta-analysis of clinical studies

PubMed 31705259 · doi:10.1007/s11154-019-09514-y · record verified 2026-08-29

What was done

A systematic review and meta-analysis of four databases up to May 2019 was performed to evaluate the efficacy and safety of very low calorie ketogenic diets (VLCKD) in individuals with overweight or obesity. Evaluated outcomes included body weight, BMI, waist circumference, body composition, blood pressure, HbA1c, lipid profiles, liver and renal function markers, and intervention discontinuation rates.

What was found

Twelve studies were analyzed. VLCKD led to weight loss of -10.0 kg (I² = 6%) for ketogenic phases under four weeks and -15.6 kg (I² = 37%) for phases of four weeks or longer, with weight loss remaining stable over up to two years of follow-up (p = 0.12). Significant reductions were reported for BMI (-5.3 kg/m²), waist circumference (-12.6 cm), HbA1c (-0.7%), total cholesterol (-28 mg/dl), triglycerides (-30 mg/dl), AST (-7 U/l), ALT (-8 U/l), GGT (-8 U/l), systolic blood pressure (-8 mmHg), and diastolic blood pressure (-7 mmHg). Serum sodium increased by +1.6 mEq/l, with no significant changes in LDL cholesterol, HDL cholesterol, serum creatinine, uric acid, or potassium. Overall discontinuation was 7.5%, comparable to standard low-calorie diets (p = 0.83).

Why it matters

The findings demonstrate that VLCKD provides clinically meaningful short-term weight reduction and improves key cardiometabolic and hepatic parameters without apparent renal or hepatic toxicity.

Limits

The abstract does not state the total number of enrolled individuals, whether the included studies were randomized controlled trials or uncontrolled cohorts, or provide confidence intervals for the effect estimates. Long-term nutritional safety and adherence beyond two years remain uncharacterized.

Cited by