What is considered the most filling food?

November 27, 2025 •

3 min read

According to a groundbreaking 1995 study from the University of Sydney, the most filling food tested was the boiled potato. The concept of 'satiety' explains why some foods keep you feeling full longer than others, a crucial factor for appetite control and weight management. This article explores what is considered the most filling food based on scientific research and nutritional factors.

Quick Summary

Explore the science behind satiety, including the groundbreaking Satiety Index study that ranked boiled potatoes highest. Understand how protein, fiber, and water content impact fullness, and discover a list of foods to help curb your appetite.

Key Points

Boiled Potatoes are Top Tier: The Satiety Index study from 1995 found that boiled potatoes were the most filling food tested, with a score of 323%.
Protein is Powerful: High-protein foods like fish, eggs, and lean meat are exceptionally good at suppressing appetite and regulating hunger hormones.
Fiber Adds Bulk: Dietary fiber, found in fruits, vegetables, legumes, and whole grains, slows digestion and adds volume, promoting a lasting feeling of fullness.
Water Content Is Crucial: Foods with high water volume, such as soups and most fruits, increase stomach distension and signal fullness with fewer calories.
Preparation Matters: How a food is prepared can alter its satiety level significantly; for instance, a boiled potato is much more filling than a fried one.
Combine for Maximum Effect: The most filling meals often combine protein, fiber, and high water content to create a low-energy-density, high-volume meal.

The Science Behind Satiety and the Satiety Index

Satiety, or the feeling of fullness and satisfaction after eating, is influenced by a complex interplay of hormonal and physiological factors. A 1995 study published in the European Journal of Clinical Nutrition developed the Satiety Index, ranking 38 foods based on how full participants felt after eating 240-calorie portions over two hours. Foods were compared to white bread, which had a score of 100. Foods scoring above 100 were more satiating, and those below 100 were less so. Factors contributing significantly to fullness included high protein and fiber content, high water or air volume, and low energy density.

The Most Satiating Foods According to Research

The boiled potato ranked highest on the Satiety Index with a score of 323%. Other top-ranking foods included:

Fish (Ling): 225%
Porridge (Oatmeal): 209%
Oranges: 202%
Apples: 197%
Brown Pasta: 188%
Beef: 176%
Eggs: 150%

Key Nutrients That Maximize Fullness

Certain nutrients are particularly effective at keeping you full.

The Role of Protein

Protein is considered the most satiating macronutrient, affecting hunger and fullness hormones like ghrelin, peptide YY, and GLP-1.

The Power of Fiber

Fiber, especially soluble fiber, slows digestion and adds bulk, contributing to lasting fullness.

Why Water Content Matters

Foods with high water content are often less energy-dense, allowing for larger portions with fewer calories, increasing stomach volume and signaling fullness. Water incorporated into food, like in soups, can be more effective than drinking water separately.

High Satiety vs. Low Satiety Foods: A Comparison


Food Item	Satiety Index Score (vs. White Bread=100)	Key Satiety Factor(s)	Preparation Note
Boiled Potato	323%	High water, volume, complex carbs, resistant starch	Best prepared without added fats.
Ling Fish	225%	High-quality protein, low energy density	A lean protein source.
Porridge (Oatmeal)	209%	Soluble fiber (beta-glucan), high water absorption	Preparation with water or low-fat milk is key.
Eggs	150%	High-quality protein, nutrient density	A protein-rich breakfast helps control appetite.
Cheese	146%	Protein, fat, texture	Often consumed in smaller portions due to high energy density.
Whole Wheat Bread	157%	Higher fiber than white bread	Slower digestion than refined grains.
White Bread	100%	Standard reference food for comparison	Quickly digested, providing short-term satisfaction.
White Pasta	119%	Processed carbohydrate, lower fiber than brown pasta	Less satiating than brown pasta.
Doughnuts	68%	High fat and sugar, low fiber	Processed and energy-dense, leading to low satiety.
Croissant	47%	Very high fat, low fiber	The lowest-ranking food on the Satiety Index.

How Food Preparation Affects Fullness

The way food is prepared significantly impacts satiety. For example, boiled potatoes are much more filling than fried potatoes (116% on the index) because frying adds energy-dense fat. Whole fruits are more satiating than juice due to their fiber content. Incorporating water, as in soups, increases volume and promotes greater fullness.

Conclusion: Building a Filling and Nutritious Diet

To effectively manage appetite, build meals around high-satiety foods combining protein, fiber, and water. Starting with soup or salad, prioritizing lean protein, choosing whole grains, and snacking on options like nuts or berries can help. Mindful eating and hydration also play a role in recognizing fullness. Strategic food choices and preparation can enhance meal satisfaction and support health goals.

Healthline provides further insight into why protein is the most satisfying macronutrient.

Frequently Asked Questions

The Satiety Index is a ranking of 38 common foods based on their ability to satisfy hunger, with white bread assigned a baseline score of 100%. Foods were ranked based on how full subjects reported feeling after consuming isocaloric (240-calorie) portions.

Boiled potatoes are very filling due to their high water content, volume, and low energy density. They are also a good source of complex carbohydrates and contain a type of protein, proteinase inhibitor 2 (PI2), which may help control appetite.

Both are crucial, but studies show protein is the most satiating macronutrient, having a strong impact on hunger hormones. Fiber provides bulk and slows digestion. Combining the two, as found in legumes and nuts, is an especially effective strategy.

While most liquids are less filling than solid foods, some liquids, like soups, are an exception. The water is incorporated into the food matrix, which slows gastric emptying and provides more lasting fullness than just drinking water alongside a meal.

Yes, nuts are highly satiating despite being energy-dense. Their high protein, fiber, and healthy fat content promotes a feeling of fullness. Studies show that including nuts as a snack can curb appetite without causing weight gain.

Processed snacks are typically low in fiber and water while being very high in energy-dense fats and refined carbohydrates. This combination leads to a quick spike in energy followed by a rapid crash, leaving you feeling less satisfied and hungry again soon after.

A high-protein breakfast, such as eggs or Greek yogurt, is highly effective at reducing hunger and calorie intake later in the day. Combining protein with high fiber, like oatmeal with nuts and berries, also provides a powerful start to your day.