The science of satiety per calorie

Energy density

Energy density refers to how many calories a food has per gram or ounce. Foods with high energy density have lots of calories packed into a small amount of food, while foods with low energy density offer fewer calories in that same amount of food.

For example, spinach has a low energy density. One would have to consume an unrealistically large volume of spinach to overeat calories. Instead, when you eat lots of spinach, you’ll fill up your stomach and get some needed nutrients without digesting many calories. 

Potato chips, donuts, and oils have a very high energy density. You don’t have to consume many grams or ounces of these foods to get a lot of calories.

Not surprisingly, multiple studies report that lower-energy-density diets correlate with improved satiety and weight loss compared to higher-energy-density diets.

Lower-energy-density foods also tend to be higher in fiber and water, and lower in starch, sugar, and fat. This may account for some, but not all, of the satiating effect.

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Fiber content

The data on fiber are more variable, but overall, fiber appears to have a beneficial effect on short-term satiety.

It’s well accepted that the fiber in fruits and vegetables helps give bulk to food, even as it is digested. This extra bulk in your digestive tract could contribute to feelings of fullness and signals to stop eating. 

However, as mentioned previously, low-energy-density foods tend to also be higher fiber foods. It is hard to tease out the effects of fiber independent of its presence in low-energy-density foods. That may be why not all studies find independent benefit from fiber supplements.

Regardless, it appears that when higher fiber levels occur naturally in foods, they contribute to short-term satiety.

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Hedonic factor

The final major contributor to satiety is a food’s hedonic factors.

Scientific data show that certain foods have addiction-like properties, stimulating someone to eat more, despite the absence of traditional hunger. Both the level of processing and combined fat and carb content contribute to the hedonic factor.

A classic example of this would be a snack food, like potato chips, that you can’t stop eating, even after you are no longer hungry.

For many people, carbs or fat by themselves — a plain baked potato or a spoonful of canola oil — may not be tempting. But the combination of them, paired together in a potato chip, is not only tempting, but hard to stop eating. 

In addition, adding sugar to any food or drink may make it more stimulating for the brain and thereby increase cravings for more.  

By choosing foods with low levels of hedonic factors, you may be better able to control your cravings and reduce your propensity to overeat unneeded calories.

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What about carbs and glycemic index?

Carbohydrate content and the glycemic index/load of individual foods did not make our list of the top four satiety factors.

That isn’t because we feel carbs and glycemic factors are not important. Not at all. In fact, some studies report higher carb foods cause more brain reward stimulation, potentially leading to overeating. 

We believe the satiety-lowering qualities of high-glycemic foods and refined or simple carbs are already accounted for in our model. This is because they tend to have lower protein content, higher energy density, lower fiber content, and higher hedonic factors.

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Other factors

There may be other factors that affect feelings of fullness or satiety, but it is unclear if they independently impact satiety similar to the four main factors listed above. 

For instance, solid and higher-viscosity foods appear to be more satiating than liquids and lower-viscosity foods. Also, more food variety can lead to increased caloric intake and reduced feeling of fullness. Even how fast you eat may influence feelings of satiety.

However, the research into these other factors doesn’t show a strong, consistent impact on satiety, above and beyond the evidence-based impact of protein percentage, energy density, fiber content, and hedonic factors.

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What are the highest satiety-per-calorie foods?

Since satiety increases with higher protein percentage, it should be no surprise that some of the highest satiety-per-calorie foods are seafood, meat, chicken, eggs, soy, and low fat dairy. And, since satiety increases with lower energy density, fibrous vegetables are also top options.

To learn more about high-satiety-per-calorie foods, please see our guide: Higher-satiety eating: the best foods

Putting it into practice

Now that you understand the science behind satiety per calorie, it’s time to put your knowledge into practice. While you can start by exploring our recipes which now include satiety scores in the nutrition information section, and try our high protein meal plans,  it can be challenging to navigate this journey without the right tool.

That’s where Hava comes in. Our innovative satiety tool simplifies the process, offering recommendations and insights to help you make the most of higher-satiety eating. Sign up for early access to Hava now.