The Claim

Very-low carbohydrate diets, defined as less than 30% of total energy from carbohydrates, are associated with significantly higher low-density lipoprotein (LDL) cholesterol levels—on average 0.35 mmol/L higher—compared to moderate-low carbohydrate diets (40–45% energy from carbohydrates), particularly when the reduction in carbohydrates is replaced with saturated fats, suggesting a potential increase in cardiovascular risk with extreme carbohydrate restriction.

Source: The Effects of Different Degrees of Carbohydrate Restriction and Carbohydrate Replacement on Cardiometabolic Risk Markers in Humans—A Systematic Review and Meta-Analysis

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
46score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Quantitative
1 study reviewed
In plain English

Eating very few carbs—like on a strict keto diet—can raise your 'bad' cholesterol, especially if you're replacing those carbs with lots of saturated fats like butter and red meat.

See the scientific wording

Very-low carbohydrate diets (<30% energy from carbs) are associated with significantly higher LDL cholesterol levels—on average 0.35 mmol/L higher—compared to moderate-low carbohydrate diets (40–45% energy from carbs), particularly when carbohydrates are replaced with saturated fats, indicating potential cardiovascular risk with extreme carbohydrate restriction.

What the research says

1 study
  1. Study: The Effects of Different Degrees of Carbohydrate Restriction and Carbohydrate Replacement on Cardiometabolic Risk Markers in Humans—A Systematic Review and Meta-Analysis

    The study shows that very-low carb diets raise bad cholesterol more than moderate-low carb diets, especially when people eat more saturated fat instead of carbs, which matches the claim.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

Fit Body Science verdict — we translate health claims into clear verdicts backed by peer-reviewed research.

Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.