While protein is an essential nutrient for your body, eating too much of it may cause negative side effects. Many weight loss and blood sugar-balancing diets promote consuming large amounts of protein and limiting intake of carbohydrates. In reality, your body probably doesn't need the excess protein and doesn't have the ability to store it as protein for later use. Eat a balanced diet of complex carbohydrates, lean protein and healthy fat to meet your nutrient needs and avoid side effects.
According to the Institute of Medicine, most adults need only about 0.8 grams of protein per kilogram of body weight, or 0.36 grams per pound. However, if you're pregnant, exercise heavily or are an athlete you may need between 1 and 1.8 grams of protein per kilogram of body weight. Your body is unable to store protein and relies on regular daily intake to maintain muscles and other body tissues and also for production of enzymes.
Consuming excess protein may cause weight gain, if you're eating excess calories. When you intake more calories than your body burns in a day, whether from protein, fat or carbohydrates, the excess calories get stored as fat. Roughly 3,500 calories make up 1 pound of body fat, according to MayoClinic.com. If you're eating more protein than you need, but not eating extra calories, the calories from protein get used as energy by your body and not stored as fat.
Dehydration and Calcium Loss
According to the American Council on Exercise, excess protein intake may cause dehydration because protein metabolism requires water. This means your need for water increases when you eat excess protein, and if you're exercising heavily or not drinking enough, you may end up dehydrated. ACE also notes that protein increases urinary calcium excretion. Over time, this chronic loss of calcium may lead to osteoporosis. To avoid these side effects, limit your protein intake to within the normal range, or be sure to consume extra fluids and extra calcium.
Excess Saturated Fat Intake
Another problem with eating excess protein is getting too much saturated fat, according to Iowa State University. You get saturated fat from animal sources, such as beef, pork, poultry skin, dairy products and butter. Consuming too much saturated fat may raise your cholesterol level and increase your chances of heart attack and stroke. To limit your saturated fat intake, choose lean proteins, such as boneless, skinless chicken breast, fish or low-fat dairy. Vegetarian foods, such as beans, nuts and seeds, also provide low-saturated fat protein.