Efficacy and safety of very-low-calorie ketogenic diet: a double blind randomized crossover study.
Efficacy and safety of very-low-calorie ketogenic diet: a double blind randomized crossover study. C Colica, G Merra, A Gasbarrini et al. European Review for Medical and Pharmacological Sciences 2017 May;21(9):2274-2289.
To evaluate the safety and efficacy of two types of short-term, very low calorie ketogenic diets (VLCK diet 1 and VLCK diet 2)
Each arm lasted 3 weeks, with 3-week washout between diets.
"VLCK diet 1 - with amino acid supplement Targets E: men 650-700kcal/d; women 450-500kcal/d, adjusted for ideal weight Carb: men 10%E (<20g/d); women 15%E (<20g/d) Protein: men 50-55%E; women 35-45%E - half protein intake came from supplement Fat: men 35-40%E; women 45-50%E Intake NR"
"VLCK diet 2 - with placebo supplement; lower protein, higher carb than VLCK diet 1 Targets E: men 650-700kcal/d; women 450-500kcal/d, adjusted for ideal weight Carb: men 15-20%E (<20g/d), women 20-25%E (<20g/d) Protein: men 45-50%E; women 25-35%E Fat: men 35-40%E; women 45-50%E Intake: NR"
"Primary: body composition Secondary: metabolic profile (lipids, HOMA-IR, weight, BMI) andexpression of Peroxisome Proliferator-Activated Receptor (PPARγ), which is involved in adipogenic transcription and has anti-inflammatory effects."
Both diets reduced weight and BMI but not total percentage of body fat. Results for other measures of body composition were mixed. NSS changes in lipid profile, FBG, and PPARy. Both diets improved insulin and insulin sensitivity levels.
"HOMA-IR WG: Y both diets BG: NR VLCK diet 1: -62.1%, p=0.01 VLCK diet 2: -59.4%, p=0.02 Quantitative Insulin Sensitivity Check Index WG: Y VLCK diet 1 only BG: NR VLCK diet 1: +18.2%, p=0.02 VLCK diet 2: NSS "
"PPARγ WG: N BG: NR Neither diet showed SS changes in gene expression analysis for PPARγ levels."
Neither diet showed negative effects on bone mineral composition or renal function.
52% dropout rate
"21-days VLCKDs not impair nutritional state; not cause negative changes in global measurements of nutritional state including sarcopenia, bone mineral content, hepatic, renal and lipid profile."
AHA - American Heart Association;
ALT - alanine aminotransferase;
AMDR - acceptable macronutrient distribution range;
AST - aspartate aminotransferase;
BG - between study groups;
BHOB - beta-hydroxybutyrate;
DBP - diastolic blood pressure;
E- energy, caloric intake;
eGFR - estimated glomerular filtration rate;
FBG - fasting blood glucose;
GGT - gamma-glutamyl transferase;
HDL-C - high-density lipoprotein cholesterol;
iGFR - isotope glomerurar filtration rate;
LDL-C - low-density lipoprotein cholesterol;
NAFLD - non-alcoholic fatty liver disease;
NR - not reported (or data needed for calculation not available);
N - no;
NA - not applicable;
NS - not specified;
NSS - not statistically significant;
SBP - systolic blood pressure;
SS - statistically significant;
TG - triglyceride;
total C - total cholesterol;
V - varied, mixed;
WG - within a study group;
WMD - weighted mean difference;
Y - yes
Number of People in Studies:
3,296 Enrolled in randomized controlled trials on 25% or less carbohydrates
2,626 Completed randomized controlled trials on 25% or less carbohydrates
79.67% 82% completion of studies
Duration of Trial
1 -2 years
# of Trials
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