Background
Methods
Search strategy and eligibility criteria
Data extraction and quality assessment
Data synthesis
Results
Source | Population | Type of KD | Comparator | Duration of diet | No. of included studies | Total participants | Outcomes | AMSTAR-2 rating |
---|---|---|---|---|---|---|---|---|
Alarim et al. 2020 [36] | T2DM adults with overweight or obesity | KD | LCD or RD | 4–8 months | 8 | 653 | Body weight, BMI, FPG, HbA1c, LDL-C, HDL-C, TC, TG | Critically low |
Amini et al. 2021 [37] | Individuals > 18 years old | KD or K-LCHF | LCD, LFD, HCD, or RD | 2 weeks to 24 months | 18 | 1835 | Body weight, BMI, muscle mass, waist circumference, fat mass, body fat percentage, visceral adipose tissue, | Moderate |
Ashtary-Larky et al. 2022 [38] | Individuals > 16 years old | KD or K-LCHF | RD or KD | 3 weeks to 3 months | 13 | 244 | BMI, muscle mass, fat mass, body fat percentage | Critically low |
Bueno et al. 2013 [1] | Adults with obesity | KD | LFD or RD | 3–6 months | 13 | 1415 | Body weight, HDL-C, LDL-C, TG, FPG, HbA1c, fasting insulin, SBP, DBP, CRP | Moderate |
Cao et al. 2021 [39] | Athletes | K-LCHF | HCD | 4–6 weeks | 10 | 139 | VO2 max, maximal heart rate during exercise, respiratory exchange ratio | Critically low |
Castellana et al. 2020 [15] | T2DM adults with overweight or obesity | VLCKD | LCD | 1–2 months | 13 | 801 | Body weight | Low |
Choi et al. 2020 [2] | Adults with overweight or obesity, some with T2DM | KD, K-LCHF, or VLCKD | LCD, LFD, HCD, or RD | 120 min to 24 months | 14 | 734 | Body weight, BMI, waist circumference, HDL-C, LDL-C, TC, TG, FPG, HbA1c, fasting insulin, HOMA-IR, SBP, DBP, CRP, creatinine, C-peptide | Critically low |
Lee et al. 2021 [40] | Adults with overweight or obesity | KD | RD | 1–6 months | 7 | 255 | Body weight, BMI, fat mass, muscle mass, waist circumference, HDL-C, LDL-C, TC, TG, FPG, VO2 peak | Critically low |
Lee et al. 2021 [17] | Athletes | KD | RD | 2–24 weeks | 8 | 158 | Body fat percentage, muscle mass, HDL-C, TC, TG, FPG, fasting insulin, heart rate, VO2 max, respiratory exchange ratio, | Critically low |
Lopez-Espinosa et al. 2021 [41] | Adults with obesity | KD, K-LCHF, or VLCKD | LCD, LFD, or HCD | 24–96 weeks | 10 | 943 | BMI, HDL-C, LDL-C, TC, TG | Critically low |
Muscogiuri et al. 2021 [42] | Adults with overweight or obesity | VLCKD | LCD | 2–4 weeks | 15 | 835 | Body weight, BMI, fat mass, muscle mass, waist circumference, FPG, HbA1C, HOMA-IR, total cholesterol, triglyceride, HDL-C, LDL-C | Critically low |
Rafiullah et al. 2022 [35] | T2DM adults | KD | RD | 1–32 weeks | 10 | 800 | Body weight, LDL-C, TG, HbA1c | Critically low |
Sainsbury et al. 2018 [34] | T2DM adults with overweight or obesity | KD | LCD or LFD | 12–24 weeks | 25 | 2784 | HbA1c | Low |
Smith et al. 2020[43] | Adults with obesity, some with dyslipidemia | KD | LDF or RD | 12–96 weeks | 25 | 3340 | Muscle mass | Critically low |
Sourbron et al. 2020 [16] | Children and adolescents (age 1–18 years) with refractory epilepsy | KD or MAD | RD | 3–16 months | 7 | 539 | Seizure frequency reduction | Critically low |
Vargas-Molina et al. 2022 | Athletes or resistance trained adults | KD | RD | 8–12 weeks | 5 | 111 | Body weight, muscle mass | Critically low |
Yang et al. 2021 [44] | Adults with cancers | KD or K-LCHF | RD | 6–24 weeks | 6 | 325 | Body weight, HDL-C, LDL-C, TC, TG, FPG, insulin, adverse effects | Critically low |
Description and summary of associations
Source | Outcome | Population | Intervention | Duration of KD | Comparator | No. of studies (sample size) | Metric | Random effect size (95% CI) | P value | I2, % | GRADE rating | Clinical importance (MCID threshold) |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Sourbron et al. 2020 [16] | Seizure frequency reduction ≥ 50% from baseline | Children or adolescents (age 1–18 years) with refractory epilepsy | KD or MAD | 3–16 months | RD | 5 (n = 374) | RR | 5.11 (3.18 to 8.21) | < .001 | 0 | High | N/A |
Rafiullah et al. 2022 [35] | Triglyceride, mg/dL | Adults with T2DM | KD | 3 months | RD | 4 (n = 283) | MD | -18.36 (-24.24 to -12.49) | < .001 | 0 | High | Yes (MCID 7.96 mg/dL) |
Rafiullah et al. 2022 [35] | Triglyceride, mg/dL | Adults with T2DM | KD | 12 months | RD | 5 (n = 445) | MD | -24.10 (-33.93 to -14.27) | < .001 | 0 | High | Yes (MCID 7.96 mg/dL) |
Rafiullah et al. 2022 [35] | LDL-C, mg/dL | Adults with T2DM | KD | 12 months | RD | 4 (n = 389) | MD | 6.35 (2.02 to 10.69) | .004 | 0 | High | Yes (MCID 3.87 mg/dL) |
Rafiullah et al. 2022 [35] | HbA1c, % | Adults with T2DM | KD | 3 months | RD | 6 (n = 388) | MD | -0.61 (-0.82 to -0.40) | < .001 | 44.0 | Moderate | Yes (MCID 0.50%) |
Castellana et al. 2020 [15] | Body weight, kg | T2DM adults with overweight or obesity | VLCKD | 4–6 weeks | LFD or RD | 2 (n = 142) | MD | -9.33 (-15.45 to -3.22) | < .001 | 0.1 | Moderate | Yes (MCID 4.40 kg) |
Cao et al. 2021 [39] | Respiratory exchange rate | Athletes | K-LCHF | 4–6 weeks | HCD | 2 (n = 15) | SMD | -2.65 (-3.77 to -1.54) | < .001 | 0.8 | Moderate | N/A |
Lee et al. 2021 [17] | Total cholesterol, mg/dL | Athletes | K-LCHF | 11–24 weeks | RD | 2 (n = 41) | MD | 1.32 (0.64,1.99) | < .001 | 0 | Moderate | No (10.05 mg/dL) |