Caffeine and coffee effects on appetite and food intake in people
What it found
Pure caffeine taken shortly before a meal slightly reduced how much people ate, while coffee had little effect.
Evidence on gut hormones and hunger feelings was mixed across short lab studies in healthy adults.
What they found
Studies in people
Coffee and meal size
Drinking coffee 3 to 4.5 hours before a meal made almost no difference to how much people ate. Median energy intake was 3144 kJ with coffee and 3164 kJ without it across three studies.
Caffeine and meal size
Taking pure caffeine 0.5 to 4 hours before a meal led to a small drop in food eaten. People consumed a median of 3017 kJ after caffeine compared to 3446 kJ after a placebo.
Daily food intake
Two studies tracked what people ate over a full day outside the lab. Coffee drinkers consumed a median of 9772 kJ compared to 10011 kJ for those who did not have coffee, a small decrease of about 230 kJ.
Stomach emptying speed
Evidence on whether coffee or caffeine speeds up stomach emptying was unclear. The median time for the stomach to half-empty was 106 minutes with coffee and 122 minutes without it.
Gut hormones and hunger
Results for gut hormones were mixed, with some studies showing rises in one hormone and others showing no change. Studies also disagreed on whether coffee or caffeine changed how hungry people felt.
What the authors conclude
- They say the current evidence is limited and mostly unclear regarding how coffee and caffeine influence appetite and food intake.
- They call for longer, well-designed trials that account for differences in genetics, taste sensitivity, and body size.
- They note that scientists do not yet know if any short-term changes in food intake would affect body weight over time.
How it was done
Many weight-loss products list caffeine as an ingredient that curbs hunger, but scientists do not yet know if it actually changes how much people eat. The authors wanted to gather the available evidence on how coffee and caffeine affect food intake and hunger signals.
The authors gathered short-term lab studies in apparently healthy adult humans. They looked at trials where people took pure caffeine or drank coffee 0.5 to 4.5 hours before eating. The studies measured how much food people ate, stomach emptying speed, gut hormones, and hunger feelings.
What it can’t tell you
- These were short lab studies, so they cannot show whether caffeine or coffee changes eating habits over weeks or months.
- Most participants were healthy-weight adults, so the results may not apply to people carrying extra weight.
- The studies used plain instant coffee or caffeine pills, which does not reflect how most people drink coffee with milk or sugar.
Who paid
- Authors work at
- Auburn University at Montgomery, USA; Griffith University, Australia
The paper
- Title
- Caffeine, coffee, and appetite control: a review
- Type
- ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Schubert MM, Irwin C, Seay RF, Clarke HE, Allegro D, Desbrow B (2017). Caffeine, coffee, and appetite control: a review. International journal of food sciences and nutrition. doi:10.1080/09637486.2017.1320537Free full textPubMed 28446037DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error