There is much confusion over satiation, satiety, and what foods to eat if you just "can't get no satisfaction". This blog lays out the basics without going into the biochemical detail.
Satiation is the process that ends an eating episode. It controls the meal size and duration. Satiety, on the other hand, is a state of non-hunger and controls subsequent hunger and food intake. Here's the extremely simplified story... When you eat, food is digested and absorbed by your GI tract. Signals are then sent to the part of your brain involved in regulation of energy intake, which stimulates satiation. You're full and you stop eating. As your digested food moves further down the GI tract to the intestine where nutrients are absorbed hormonal signals are again integrated in the brain to induce satiety and your fullness continues even after you've stopped eating.
Why is satiation and satiety so important? Because these "gut reactions" have the potential to control calorie intake. If we listen to our gut signals, as detailed in another blog, we'd stop eating when we were full and not eat again until we were physically hungry (i.e., hunger pangs). But, external factors like large portions, availability of great tasting food, eating in social situations, boredom and other psychological triggers often cause us to ignore our internal signals and eat when we are not truly hungry. While techniques to improve mindful eating have been described in previous blogs we have not discussed the potential of certain foods to enhance or reduce satiation or satiety.
So, can specific nutrients or foods be more satisfying than others? Yes! Some studies have shown that calories from protein are more satiating than calories from carbohydrate or fat. But, the characteristic of a food that appears to have the most impact on both satiation and satiety is energy density. That is, the amount of energy a food contains per weight, or calories in a portion of food. Fruits, vegetables, beans, and cooked grains are low energy density foods. High energy density foods have more fat and less water. Studies have shown that satiation and satiety are increased after consuming high volume, low energy density foods. Thus, starting a meal with two cups of leafy greens and chopped vegetables will lead to greater satisfaction and less eaten during the main meal than starting a meal with a few mozzarella sticks. Eating low energy density foods does not necessarily mean eating more volume of food. It means eating foods with more water and fiber. This can be done by adding fruits, vegetables, beans, and whole grains to meals. And reducing high-fat meats, cheeses, sauces, and dressings in meals. Need a satisfying 100-calorie snack? Choose 1 cup of grapes instead of 1/4 cup raisins or 18 peanuts.
Give it a try! Order soup (broth-based) and salad for lunch today instead of a hamburger and let us know how satiated you are and how long your satiety lasts!
Rolls, B.J. (2000). The Role of energy density composition and obesity: do we need to look beyond dietary fat?. Journal of Nutrition, 130, 268S-271S.