Gut peptides PYY3-36, GIP, and GLP-1 released after meals were strongly associated with feelings of fullness and satisfaction, though adding avocado to meals actually decreased GLP-1 levels.
P < 0.001Strong associations between PYY3-36 and GIP levels and multiple appetite sensation measures after meals
What the researchers found
In a crossover trial comparing three lunch meals (control, avocado-inclusive, avocado-added):
- The avocado-added meal decreased the 3-hour GLP-1 AUC compared to control (P = 0.03)
- PYY3-36 and GIP showed negative associations with hunger, desire to eat, and 'how much could you eat' (all P < 0.001)
- PYY3-36 and GIP showed positive associations with fullness, satisfaction, and composite appetite score (all P < 0.001)
- GLP-1 was negatively associated with hunger and positively associated with satisfaction and composite score (all P < 0.05)
- Ghrelin (the hunger hormone) results were not highlighted as significant
Why it matters
Understanding how different foods affect satiety peptide release is key to designing diets that naturally promote fullness and reduce overeating. This study shows that the relationship between food composition and gut peptide responses is complex — adding a healthy fat like avocado doesn't necessarily increase appetite-suppressing peptides like GLP-1.
How the study worked
Randomized 3×3 crossover design with 26 healthy overweight adults. Three test meals separated by one week: avocado-free control, isocaloric avocado-inclusive, and higher-calorie avocado-added. Blood samples collected at multiple time points measured ghrelin, PYY3-36, GIP, and GLP-1. Appetite sensations assessed via visual analog scales at matching time points. Mixed models and regression analysis evaluated differences and associations.
What this study cannot tell us
Small sample (26 participants) limits statistical power. Single-meal acute testing may not reflect chronic dietary patterns. The avocado-added meal was higher in calories than the control, confounding the comparison. Only overweight adults were studied; normal-weight or obese individuals may respond differently. The clinical significance of the GLP-1 decrease with avocado is unclear.
How to read the evidence
This is a small randomized crossover trial in humans — a solid design for acute postprandial studies, though the small sample size and single-meal design limit the strength of conclusions.
When this study was published
Published in 2018 in Eating Behaviors. While a few years old, the findings on gut peptide-appetite associations remain relevant to current understanding of satiety peptide physiology.
The bigger picture
This study illustrates how the gut peptide system — GLP-1, PYY, GIP, and ghrelin — orchestrates appetite regulation in response to food. As GLP-1 receptor agonist drugs become mainstream for weight loss, understanding how diet naturally modulates these same peptides could inform complementary nutritional strategies.
Questions still open
- Why did adding avocado (a healthy fat) decrease GLP-1 levels rather than increase them?
- Could dietary strategies that maximize PYY and GIP release enhance the effectiveness of GLP-1 receptor agonist medications?
- Do different types of dietary fats (monounsaturated vs. saturated) have different effects on gut peptide release?
Common questions
What gut peptides control appetite after eating?
Should I eat avocado for appetite control?
Read the original research
Postprandial gut hormone responses to Hass avocado meals and their association with visual analog scores in overweight adults: A randomized 3 × 3 crossover trial.
Eating behaviors, 31, 35-40
Citation
Haddad, Ella; Wien, Michelle; Oda, Keiji; Sabaté, Joan. (2018). Postprandial gut hormone responses to Hass avocado meals and their association with visual analog scores in overweight adults: A randomized 3 × 3 crossover trial.. Eating behaviors, 31, 35-40. https://doi.org/10.1016/j.eatbeh.2018.08.001