Can a person consume too much protein in a day? What would happen if a person did consume too much?
Yes, a person can eat too much protein in a day. Protein, when eaten, is digested then absorbed as amino acids. Amino acids are normally used to build protein structures in the body such as organs and muscles, but they can be converted to body fat.
For example, the adult male needs 56 grams of protein a day. That could include 3- 8-ounce glasses of milk and 4.5 ounces of meat (about the size of a quarter pound hamburger), poultry, fish, eggs, cheese, or soybeans (tofu). This would not include the protein also found in starches, grains, vegetables, and nuts. Most people in the U.S. eat too much protein and not enough vegetables, fruits, and whole grains.
Excess protein is scavenged for the glucose molecule which can be then be either used as fuel for your body or stored in your liver or muscles as glycogen. If the liver and muscle glycogen (complex glucose molecule) stores are full, then excess protein is stored as body fat. So eating excess protein can make some rather expensive body fat.
Some athletes may need more protein if they have a large muscle mass such as football players and bodybuilders. They may need almost twice the amount of protein, but this would only amount to less than 500 calories of protein per day.
Since many food sources of protein (beef, pork, poultry, and fish) take a lot of grain and water to grow, eating excess protein is also a waste of natural resources.