People on low-carb diets saw their blood pressure drop a little bit more than those on low-fat diets, which might help their heart health.
Claim Context
In overweight adults, a low-carbohydrate diet is associated with modest reductions in systolic and diastolic blood pressure over four weeks compared to a high-carbohydrate, low-fat diet.
“Small but significant reductions was also observed in both systolic and diastolic blood pressure in the low-carbohydrate than the high-carbohydrate group.”
Evidence from Studies
No evidence studies found yet.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
Whether low-carb diets consistently reduce blood pressure more than low-fat diets in overweight adults.
A systematic review and meta-analysis of 20+ RCTs comparing isocaloric low-carb (<30% carbs) and low-fat (<30% fat) diets in overweight adults, measuring systolic and diastolic BP at 4, 12, and 24 weeks.
Causal effect of diet type on blood pressure changes in overweight adults.
A double-blind RCT of 150 overweight adults randomized to 12 weeks of isocaloric low-carb (<20% carbs) or low-fat (<20% fat) diets, with automated BP measurements at baseline, 4, 8, and 12 weeks, and sodium intake controlled.
Long-term association between dietary carbohydrate intake and blood pressure changes in free-living adults.
A prospective cohort of 2,000 adults followed for 3 years, with annual BP measurements and validated dietary assessments, adjusting for sodium intake, physical activity, and medication use.
Correlation between current carbohydrate intake and blood pressure levels in a population.
A cross-sectional survey of 4,000 adults measuring daily carb intake via food diary and BP via automated device, adjusting for age, BMI, and salt intake.
Anecdotal observation of BP reduction after adopting a low-carb diet.
A case series of 5 individuals documenting BP changes before and after 4 weeks of low-carb dieting without medical supervision.