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Diets

ketogenic diet decreases appetite

In plain terms: Does a low-carb keto diet reduce hunger?

Leans support Diets 🔬 Includes disconfirming

Part of: 🥗 ketogenic diet

RefutedContestedStrong support
consensus score 0.33

Likely — keto modestly curbs hunger by blunting the appetite spike of dieting, though some controlled trials find no real advantage.

📅 Last reviewed: 2026-07-15

Evidence ladder

How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."

Top evidence so far: All trials, pooled (Meta-analysis)

MechanismIn-vitroAnimalObservationalRCTMeta-analysis

How the studies fall

7 support 2 contradict 0 tested null 6 mixed · 15 sources, 9 independent groups

What the evidence shows

Ketosis modestly blunts appetite - mainly by preventing the hunger increase that normally accompanies calorie restriction, rather than strong active suppression.

The evidence (16)

SourceGradeStanceQualityFinding
Sommersten 2023
2023 · J Nutr
RCT supports moderate isocaloric LCHF suppresses post-fat-loss appetite increase
Lundanes J et al
2025 · study_type: RCT
RCT mixed low 8wk RCT, lipedema+obesity women: LCD (75g CHO, likely sub-ketogenic) reduced hedonic hunger 'Food Present' PFS score (p<0.001) vs no change in low-fat; between-group Food Present diff p=0.050
Cintoni M et al
2026 · study_type: RCT
RCT mixed low KOMPARC RCT (n=33) in radiotherapy patients: KD group reported increased appetite loss vs Mediterranean-diet control (patient-reported QoL), p not given for this specific item
Lyngstad
2019 · Am J Clinical Nutrition
observational supports moderate Ketosis blunted the weight-loss-induced rise in appetite in both sexes; ghrelin and hunger suppressed during the ketogenic phase.
Nymo
2017 · Int J Obesity
observational mixed moderate During ketogenic weight loss hunger was suppressed while ketosis maintained; hunger rose once refeeding lowered BHB, supporting ketosis-appetite link.
Struik
2020 · J Nutrition
RCT contradicts moderate In energy-restricted T2D, very-low-carb and high-carb diets gave comparable fasting appetite; high-carb gave GREATER daily fullness, against keto.
Sumithran 2013
2013 · Eur J Clin Nutr
RCT supports moderate ketosis after weight loss prevents the expected rise in ghrelin/hunger
Hu
2016 · Nutr Metab Cardiovasc Dis
RCT mixed moderate Low-carb preserved satiety (less PYY drop) vs low-fat, but no between-group difference in ghrelin or self-reported appetite over 1 year.
Deemer SE, Plaisance EP, Martins C
2020 · Nutrition Research
meta-analysis supports moderate NARRATIVE REVIEW, zero weight. Stated aim: 'The aim of this review is to describe the status of knowledge regarding the impact of ketosis, induced by diet or exogenous ketones (ketone esters), on appetite and the potential mechanisms involved.' Its conclusion is on the claim's side and matches the claim's own scope line: 'Ketogenic diets (KDs) have been shown to prevent an increase in ghrelin secretion, otherwise seen with weight loss, as well as to reduce hunger and/or prevent hunger.' But the authors also record that 'the exact threshold of ketosis needed to induce appetite suppression, as well as the exact mechanisms that mediate such an effect, has yet to be elucidated.' No n, no effect size, no interval — nothing pooled. Stored grade 'meta-analysis' is wrong and is flagged for cultivar to rule; the review role zeroes the row either way. Senior author C Martins also authors several other counting rows on this claim under separate group_ids (independence flag, not fixed here). Abstract only — Europe PMC reports no open-access full text.
Ghamdi
2026 · Pediatric Obesity
RCT contradicts moderate In adolescents with obesity, lowering meal carbohydrate did not alter satiety, food reward, or subsequent energy intake (null for keto appetite effect).
Lundanes
2025 · Clin Nutr ESPEN
RCT supports moderate Isocaloric low-carb diet reduced postprandial ghrelin and increased fullness vs low-fat in women with lipedema.
Stubbs
2018 · Obesity
RCT mixed moderate Exogenous ketone-ester drink raising BHB lowered plasma ghrelin and subjective hunger vs isocaloric dextrose, isolating ketones as the appetite signal.
Bahrami F et al
2026 · study_type: RCT
RCT supports moderate 3d eucaloric KD in humans: BHB rose ~10x; baseline pancreatic polypeptide 3-36 (satiety hormone) increased, authors interpret as appetite-suppressive signal vs LCD
Gibson AA, et al.
2015 · Obes Rev
meta-analysis supports moderate SR/MA of VAS appetite studies: less hunger/greater fullness despite weight loss (absolute change small)
Roekenes
2021 · Curr Opin Clin Nutr Metab Care
meta-analysis mixed moderate Review: ketogenic diets attenuate the expected hunger increase after weight loss, though the ketosis threshold and magnitude remain uncertain.
Grabowski M et al
2026 · Research Square
animal supports moderate Mouse KD 14d: reduced snack-directed behavior/food intake (caloric intake unchanged due to energy density); hypothalamic Ghsr↓, Cart/Mc3r↑; Agrp↑ in lean mice did not cause hyperphagia

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