I often hear friends and family say “Protein gives me energy,” or “I feel more energized when I eat something with protein.” I too feel this way after eating a meal that is predominantly made of protein; however, this perceived benefit isn’t exactly consistent with what we know about the basic definition of protein and its role in nutrition. But does protein give you energy?
When we look at protein’s role in the body, protein does not usually get used for energy (that role is mainly played by carbohydrate-containing foods). Protein is made up of “building blocks” called amino acids. Many of these amino acids are essential, meaning we must get them from our diet because our bodies cannot make them. This is one reason why eating high-quality protein (i.e., protein foods that contain all the essential amino acids, such as dairy foods like milk, cheese or yogurt) is important for health. When digested, these amino acids are used to help maintain healthy muscles, bones and other systems and structures in the body. This is an important role, and the reason why many scientists have suggested that consuming higher protein diets from high-quality sources is important, particularly as we age.
So why do people associate eating protein with feeling “energized?” Perhaps there are a few reasons that may have some scientific basis:
- Eating a diet higher in protein may help us feel fuller. The science is well established that, in general, protein is more satiating than an equal amount of calories from carbohydrate or fat. This is true after a single meal and, as part of a higher protein diet, could contribute to satiation throughout the course of a day. Therefore, it is possible that when people perceive having more energy when eating a higher protein diet, rather than an increase in energy what they may really be experiencing is a lack of hunger. It is possible this may be interpreted as “increased energy,” but this assumption would need to be scientifically tested.
- Protein may help us avoid a “sugar crash.” Many of us can identify with the “sugar crash” that can occur when eating meals high in sugar. You may get a burst of initial energy, but then later you may feel sluggish. Some research has shown that eating a protein-rich meal or a meal balanced with protein and certain carbohydrate results in a smaller rise in blood sugar than a carbohydrate-rich meal. In fact, one study even found that consuming whey protein before a meal resulted in a smaller increase in blood sugar after the meal. Therefore, consuming meals that balance the protein-to-carbohydrate ratio may help avoid this “sugar crash,” and this may lead to the perception that protein “improves energy.”
- A higher protein diet was found to improve sleep quality during weight loss. A recently published study found that eating a greater proportion of calories from protein while dieting improved self-reported sleep quality in overweight and obese adults. This is the first study to have found such a relationship between protein and sleep, so more research is needed to confirm these results, but if these data are true for other populations, it could contribute to feeling more energized while eating a higher protein diet.
While there are a number of potential explanations for why people may perceive “more energy” when eating protein, one thing is clear: quality dietary protein -- as is found in dairy foods like milk, cheese and yogurt -- is important for overall health. In addition to high-quality protein, the dairy food group contributes nutrients such as calcium, vitamin D and potassium in Americans’ diets. So continue to enjoy your favorite protein foods, whether for perceived “energy” or other important health benefits.