Research

Energy balance

There is no conclusive evidence that varying the relative quantities of dietary carbohydrates and fats (macronutrient partitioning) significantly affects the degree of weight loss or the duration of weight maintenance beyond the effects of total caloric intake.

Do not expect a specific macronutrient ratio (low-carb vs. low-fat) to give you a metabolic advantage for long-term weight loss if you are eating the same number of calories. The science shows that both diets work equally well for weight maintenance when calories are matched. Focus on finding a diet you can adhere to long-term, as compliance is the primary driver of success, not the specific ratio of carbs to fats.

GoodRefutesHIGH confidence
Overall, there is no conclusive evidence that the degree of weight loss or the duration of reduced weight maintenance are significantly affected by dietary macronutrient quantity beyond effects attributable to caloric intake.
Heather Seid et al. · Nutrients · 2019

Why this rating

Based on a narrative review of multiple meta-analyses and controlled inpatient/outpatient studies, though the authors note limitations in long-term outpatient data.

Source

Low Carbohydrate and Low-Fat Diets: What We Don’t Know and Why We Should Know It

Heather Seid et al. · Nutrients · 2019

DOI 10.3390/nu11112749

narrative_reviewCited 67×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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