Do ketogenic diets really suppress appetite? A systematic review and meta-analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of clinical trials
PubMed 25402637 · doi:10.1111/obr.12230
What was done
Authors conducted a systematic review and meta-analysis of studies evaluating subjective appetite ratings using visual analogue scales (VAS). Appetite was compared before the intervention (during energy balance) and during adherence while in ketosis, examining both very-low-energy diets (VLEDs) and ketogenic low-carbohydrate diets (KLCDs).
What was found
The abstract reports no numerical values, effect sizes, or confidence intervals. Adherence to VLEDs was associated with less hunger and greater fullness/satiety. Adherence to KLCDs was associated with less hunger and a reduced desire to eat. The absolute reductions in subjective appetite ratings were described as small, but occurred despite active energy restriction.
Why it matters
Weight loss through caloric restriction typically triggers a compensatory increase in appetite. Establishing that ketosis blunts or prevents this expected increase provides a clinical rationale for using ketogenic protocols to aid short-term dietary adherence.
Limits
The abstract does not state the number of included studies, total participant count, or exact quantitative effect sizes. Appetite assessment relied solely on subjective visual analogue scales rather than objective biomarker measurements, and the minimum threshold of ketosis needed to suppress appetite was not established.
Cited by
- supports Starting a ketogenic diet lowers blood glucose and insulin levels, causing an immediate loss of water weight followed by an automatic reduction in caloric intake.