Research

Mixed

There is no clinically relevant difference in individual response heterogeneity (variability in body mass change) between low-carbohydrate and low-fat diets.

If you are choosing between a low-carbohydrate and a low-fat diet for weight loss, do not expect one to be inherently more 'unpredictable' or variable in its results than the other. The variability in how much weight people lose is similar for both approaches. Therefore, the choice should be based on preference, adherence, and health markers rather than an expectation of superior or inferior individual response variability.

GoodRefutesMEDIUM confidence
Evidence is insufficient to suggest the response heterogeneity to low-CHO diets differs from that observed with low-fat diets.
Ella S. Smith et al. · Obesity · 2020

Why this rating

High-quality systematic review and meta-analysis of 25 RCTs with 3,340 participants, though the confidence intervals for the variance estimate were wide.

Source

A Systematic Review and Meta‐Analysis Comparing Heterogeneity in Body Mass Responses Between Low‐Carbohydrate and Low‐Fat Diets

Ella S. Smith et al. · Obesity · 2020

DOI 10.1002/oby.22968

Meta-analysis · 25 studiesCited 19×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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