What Makes a Food Filling?
Satiety is a term used to explain the feeling of fullness and loss of appetite that happens after eating.
A scale called the satiety index measures this effect. It was developed in 1995, in a study that tested 240-calorie servings of 38 different foods.
The foods were ranked according to their ability to satisfy hunger. Foods that scored higher than 100 were considered more filling, while foods that scored under 100 were considered less filling.
What this means is that eating foods that score higher on the satiety index can help you eat fewer calories overall.
Filling foods tend to have the following characteristics:
High in protein: Studies show that protein is the most filling macronutrient. It changes the levels of several satiety hormones, including ghrelin and GLP-1 .
High in fiber: Fiber provides bulk and helps you feel full for longer. Fiber may slow down the emptying of the stomach and increase digestion time.
High in volume: Some foods contain a lot of water or air. This may help with satiety as well (9,12).
Low in energy density: This means that a food is low in calories for its weight. Foods with a low energy density are very filling. They typically contain a lot of water and fiber, but are low in fat (3, 6, 9, 10).
Whole, unprocessed foods are also generally more filling than processed foods.BOTTOM LINE:Filling foods tend to have certain characteristics, such as being high in protein or fiber. These types of foods tend to score high on a scale called the satiety index.
1. Boiled Potatoes
Potatoes have been demonized in the past, but are actually very healthy and nutritious.
Cooked, unpeeled potatoes are a good source of several vitamins and minerals, including vitamin C and potassium .
Potatoes are high in water and carbs, and contain moderate amounts of fiber and protein. They also contain almost no fat .
Compared to other high-carb foods, potatoes are very filling.
In fact, boiled potatoes scored a 323 on the satiety index, which is the highest number of all 38 foods tested. They scored nearly 7 times higher than croissants, which scored the lowest (1
One study found that eating boiled potatoes with pork steak led to lower calorie intake during the meal, compared to eating the steak with white rice or pasta .
Some evidence indicates that part of the reason why potatoes are so filling is because they contain a protein called proteinase inhibitor 2 (PI2). This protein may suppress appetite .
BOTTOM LINE:Boiled potatoes are very filling, and scored the highest of all the foods on the satiety index. They can fill you up and help you eat fewer calories in total.
Eggs are incredibly healthy and nutrient-dense.
Most of the nutrients are found in the yolks, including the antioxidants lutein and zeaxanthine, which may benefit eye health .
Eggs are a great source of high-quality protein. A large egg contains around 6 grams of protein, including all 9 essential amino acids.
Eggs are also very filling and score high on the satiety index .
One study found that eating eggs for breakfast, rather than a bagel, increased fullness and led to less calorie intake over the next 36 hours .
Another study found that a protein-rich breakfast of eggs and lean beef increased fullness and helped people make better food choices .
BOTTOM LINE:Eggs are a nutritious, high-protein food with a powerful impact on fullness. They may help you eat less for up to 36 hours after a meal.
Oats, eaten as oatmeal (porridge), are a popular breakfast choice. Oatmeal is fairly low in calories and a great source of fiber, particularly a soluble fiber called beta-glucan. It also scores high on the satiety index, ranking 3rd overall .
One recent study found that participants felt more full and less hungry after eating oatmeal, compared to ready-to-eat breakfast cereal. They also ate fewer calories during lunch .
Oatmeal’s filling power comes from its high fiber content and its ability to soak up water.
Soluble fiber, such as the beta-glucan in oats, can help you feel full. It may also help release satiety hormones and delay the emptying of the stomach .
BOTTOM LINE:Oatmeal is a very filling breakfast choice. It may help you eat fewer calories in the following meal and delay emptying of the stomach.
Fish is loaded with high-quality protein.
Fish is also rich in omega-3 fatty acids, which are essential fats that we must get from food.
According to one study, omega-3 fatty acids may increase the feeling of fullness in people who are overweight or obese .
Additionally, some studies indicate that the protein in fish may have a stronger effect on fullness than other sources of protein.
On the satiety index, fish scores higher than all other protein-rich foods, including eggs and beef. Fish actually had the second highest score of all the foods tested .
Another study compared fish, chicken and beef protein. The researchers found that fish protein had the strongest effect on satiety .
BOTTOM LINE:Fish is rich in protein and omega-3 fatty acids, which may increase the feeling of fullness. The protein in fish may have a stronger effect on fullness than other types of protein.
Liquids have often been considered to be less filling than solid foods, although the evidence is mixed (28, 29).
However, soups are a bit different. Research shows that soups may actually be more filling than solid meals containing the same ingredients (30, 31).
In one study, volunteers consumed a solid meal, a chunky soup or a smooth soup that had been put through a food processor.
The feeling of fullness and the rate at which the food left the stomach were then measured. The smooth soup had the greatest impact on fullness and the slowest rate of stomach emptying, followed by the chunky soup .