Eating very few carbs and more fats for 12 weeks makes the dangerous belly fat around organs shrink by about a quarter in people who have too much body fat.

Scientific Claim

A very low-carbohydrate high-fat diet significantly reduces visceral adipose tissue mass by approximately 23% in overfat adults after 12 weeks, independent of exercise intervention.

Evidence Quality Assessment

Claim Status

overstated

Study Design Support

Design supports claim

Appropriate Language Strength

probability

Can suggest probability/likelihood

Assessment Explanation

The study shows association between VLCHF diet and VAT reduction, but total energy intake also decreased in VLCHF groups, so the effect may be partly due to caloric deficit rather than macronutrient composition alone. Authors acknowledge this limitation.

More Accurate Statement

“A very low-carbohydrate high-fat diet is associated with a significant reduction in visceral adipose tissue mass by approximately 23% in overfat adults after 12 weeks, though this effect may be partly due to reduced caloric intake.”

Source Excerpt

“VAT mass (g) reduced by 23.2 % (median; 95% CI: [25.9; 17.0] %) in the VLCHF group and 17.6 % [23.9; 12.0] in the VLCHF+HIIT group while these changes were not significant after 12 weeks in both the HIIT and Control groups.”

Evidence from Studies

Supporting Evidence (1)

Why it supports

The RCT design with randomization and control group shows a statistically significant VAT reduction specifically in VLCHF groups compared to HIIT and control groups. The study measured VAT mass using DXA, which has high reliability (ICC > 0.98), and found consistent reductions across multiple time points.

60

Score

Effects of a Very Low-Carbohydrate High-Fat Diet and High-Intensity Interval Training on Visceral Fat Deposition and Cardiorespiratory Fitness in Overfat Individuals: A Randomized Controlled Clinical Trial

RCT

Overstated

⚠️ Overstated

The study shows association between VLCHF diet and VAT reduction, but total energy intake also decreased in VLCHF groups, so the effect may be partly due to caloric deficit rather than macronutrient composition alone. Authors acknowledge this limitation.

More accurate phrasing:

“A very low-carbohydrate high-fat diet is associated with a significant reduction in visceral adipose tissue mass by approximately 23% in overfat adults after 12 weeks, though this effect may be partly due to reduced caloric intake.”

Source Study

Effects of a Very Low-Carbohydrate High-Fat Diet and High-Intensity Interval Training on Visceral Fat Deposition and Cardiorespiratory Fitness in Overfat Individuals: A Randomized Controlled Clinical Trial

Score: 60

DOI: 10.3389/fnut.2021.785694

Similar Assertions

Adding high-intensity interval training to a very low-carb diet doesn't make the belly fat reduction any better than just doing the diet alone in people with excess body fat.

82%

When people with excess body fat eat very few carbs and more fats, they lose about 4-5% of their muscle mass within a month, and this muscle loss continues for the full 12 weeks of the diet.

81%

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.

78%

Adding high-intensity interval training to a very low-carb diet doesn't stop the muscle loss that happens when people with excess body fat eat very few carbs for 12 weeks.

76%

Eating very few carbs and more fats for 12 weeks doesn't improve the maximum oxygen your body can use during exercise in people with excess body fat when measured in absolute terms.

72%