Whenever you eat a hamburger, a flank steak or a black bean burger have you realized that you tend to fill up a lot faster? You’re not just imagining things. There is a reason that a high protein diet seems to align with weight loss and why we reach for protein packed snacks to hold off hunger until our next meal.
To understand why protein makes and keeps us full, first we need to look at how the body signals to the brain that it is full. When we eat something, our stomachs expand, stimulating receptors on the lining of the stomach that recognize how much food it contains. More food in the stomach means a longer time to digest, which means the stomach signals to the brain that it is full. When the stomach empties, those receptors are not stimulated anymore and we begin to feel hungry again.
Protein contributes to satiety (feeling of fullness) more than carbohydrates or fat, especially when combined in a high fiber meal. Why is this?
There are two mechanisms in protein that have been studied that work to keep our bellies satisfied longer. First, protein just takes longer to digest so it stays in the stomach longer than, say, a piece of white bread. White bread is mostly easily digestible sugar and will quickly move out of the stomach, whereas a piece of chicken has many different elements that need to be broken down by stomach acids and digestive enzymes before leaving the stomach.
Second, protein releases certain hormones and peptides that, when broken down, actually block the receptors that tell us we are hungry. Once that pork chop or hard boiled egg has started to break down, the hormones do their work and let our brains know we are starting to get full faster than it takes to eat a piece of cake. Literally.
On average, we should be getting about 0.8 grams of protein per kg of body weight, or 56 grams per day for men and 46 grams per day for women, for optimal satiety and health.
In combination with the correct amounts of carbohydrate and fat, protein is an essential part of any diet.
So next time you are faced with the life changing question of, “Do you want this barbeque pulled pork?” You say YES.