Eating very few carbs and more fats for 12 weeks makes people with excess body fat lose about 6-9 centimeters from their waist size.
Scientific Claim
Very low-carbohydrate high-fat diets significantly reduce waist circumference by approximately 6-9 cm in overfat adults after 12 weeks of intervention.
Evidence Quality Assessment
Claim Status
overstated
Study Design Support
Design supports claim
Appropriate Language Strength
probability
Can suggest probability/likelihood
Assessment Explanation
While the study shows association between VLCHF diet and waist circumference reduction, the total energy intake also decreased in VLCHF groups, so the effect may be partly due to caloric deficit rather than macronutrient composition alone.
More Accurate Statement
“Very low-carbohydrate high-fat diets are associated with significant reductions in waist circumference by approximately 6-9 cm in overfat adults after 12 weeks of intervention, though this effect may be partly due to reduced caloric intake.”
Source Excerpt
“Waist circumference (cm) decreased by −6.3 (−8.6; −4.7)** in the VLCHF group and −9.4 (−11.8; −7.9)** in the VLCHF+HIIT group”
Evidence from Studies
Supporting Evidence (1)
The RCT design shows statistically significant reductions in waist circumference specifically in VLCHF groups compared to control and HIIT groups. The study measured waist circumference using bioelectrical impedance analyzer, which has established reliability for this measurement.
⚠️ Overstated
While the study shows association between VLCHF diet and waist circumference reduction, the total energy intake also decreased in VLCHF groups, so the effect may be partly due to caloric deficit rather than macronutrient composition alone.
More accurate phrasing:
“Very low-carbohydrate high-fat diets are associated with significant reductions in waist circumference by approximately 6-9 cm in overfat adults after 12 weeks of intervention, though this effect may be partly due to reduced caloric intake.”