Satiety Index
Satiety Index — The satiety index is a numerical ranking of how filling individual foods are per calorie consumed, originally developed by Susanna Holt and colleagues at the University of Sydney in 1995. Foods are scored relative to white bread (set at 100); a higher index indicates greater satiety per calorie. Boiled potatoes scored highest in the original study at 323.
What is the satiety index?
The satiety index is a research-derived measure of how full a food makes a person feel per calorie. The methodology was first published in Holt et al., 1995, in the European Journal of Clinical Nutrition. In the original study, healthy participants ate isocaloric (240 kcal) portions of 38 different foods; their fullness was scored every 15 minutes for two hours after each test meal.
Each food’s satiety score is expressed relative to white bread, which is set at 100. Selected results from the original study:
- Boiled potatoes: 323
- Fish: 225
- Oatmeal: 209
- Oranges: 202
- Apples: 197
- Eggs: 150
- White bread (reference): 100
- Cake: 65
- Croissants: 47
How is satiety determined?
Satiety is influenced by several factors that the index implicitly captures:
- Protein content — high satiety per calorie
- Fiber content — slows gastric emptying
- Water content — adds volume without calories
- Energy density — calorie-dilute foods produce more fullness per calorie
- Palatability and processing — heavily processed, hyperpalatable foods score lower
These overlapping factors mean that boiled potatoes (high water content, moderate fiber, modest energy density) outperform calorie-equivalent croissants (low water, low fiber, high energy density).
Why satiety matters for weight management
For users tracking calories with the goal of weight loss, choosing higher-satiety-index foods improves dietary adherence by reducing hunger between meals. This is conceptually related to the protein leverage hypothesis and aligns with research showing that low-energy-density, high-protein, high-fiber meals reduce ad libitum calorie intake.
The original satiety index has not been formally updated, and a single 1995 study with ~12 participants per food has obvious limitations. It remains, however, a useful conceptual tool. See also glycemic index and macronutrient.