Does Fat or Protein Make You Full?

Eating the right combination of nutrients can make you feel fuller longer. Nutrients like protein, fat and fiber-rich carbohydrates increase satiety while helping you meet your nutritional needs. The best way to increase fullness is to include foods high in these filling nutrients in each meal and snack.

A plate of shrimp, veggies and noodles. (Image: Kanachai_morarat/iStock/Getty Images)

Protein

Protein has been shown to increase fullness. A 2005 study in "The American Journal of Clinical Nutrition" showed that a high protein diet increased satiety and decreased appetite and calorie intake. Participants in the study consumed 35 percent of total calories from protein, which is on the high end of the Institute of Medicine recommendation of 10 to 35 percent. Most adults only need 6 to 7 ounces of protein daily, about the size of about two decks of cards.

Fat

The effect of fat on satiety is complicated. When fat enters the small intestine, it slows digestion, increases fullness and decreases appetite. However, regular consumption of high-fat foods has been shown to increase the amount of calories consumed, according to a 2007 review in "The American Journal of Clinical Nutrition." This may be due to the fact that fat is more calorie dense than other nutrients like protein and carbohydrates. The Institute of Medicine recommends that 20 to 35 percent of total calorie intake should be from fat.

Other Filling Nutrients

Other nutrients like water, fiber and vitamins can affect appetite. Water and fiber-rich foods like fruits and vegetables take up more space in your stomach, making you feel fuller. Soluble fiber found in fruits, vegetables and legumes expands in the stomach and slows the rate of gastric emptying. Adequate vitamin intake may also affect appetite. Participants in a 2008 study in "British Journal of Nutrition" reported reduced appetite with multivitamin supplementation compared to those who took a placebo.

Considerations

Choosing healthy sources of protein and fat can decrease your risk of heart disease and diabetes. Unhealthy saturated fat can be found primarily in animal and dairy products. Better protein sources, lower in saturated fats, include tofu, beans and nut butters. If you are going to consume animal products, choose lean cuts of meat, skinless poultry and fish. Unsaturated fat may decrease your risk of heart disease and diabetes and come mostly from plant sources like avocados, nut butters, olives and canola oil.