Most nutrition and fitness or sports experts agree that people doing intensive exercise, whether for their own personal satisfaction or for competitive reasons, can meet their nutritional needs through a well-balanced diet consisting of good quality food and plenty of liquids. Any diet can and should be tailored to meet our individual needs. It should always stick to the same basic principles and include simple guidelines. Unfortunately, many amateur exercise fans, professional athletes, and trainers are misinformed about good nutrition and a well-balanced diet for optimum physical activity.
Protein requirements 
The Institute of Medicine recommends that adults should get 45 to 65% of their calories from carbohydrates, 20 to 35% from fat, and 10 to 35% from protein. Though research has yet to define the exact amount of protein that adults with varying intensity and duration of physical activity need, we know that exercising increases your energy (calorie) needs and thus your need for carbohydrates, protein, and fat.
Many active people feel they need to load their diets with protein. They often do this by consuming non-food sources of protein, such as diet supplements/shakes that contain an excessive amount of this nutrient. Protein supplements are expensive and don’t provide any added benefit that food cannot provide. Our bodies can get enough protein from eating foods that contain protein such as: meats, dairy products, eggs, beans/legumes, and soy products.
The impact of excess protein consumption
The body is not able to store extra protein. Protein consumed in excess of the body's needs is not used to build muscle, but, it is used for other bodily functions.
If individuals consume protein in excess of their calorie and protein needs, the extra protein will not be stored as protein. Unfortunately such extra protein is converted to and stored as fat. As a result, if individuals consume large amounts of extra protein in addition to their regular dietary intake, any weight gain would very likely be in the form of fat.
Another important point to keep in mind is that the potential for harm exists if protein is consumed in excess. Such harm is most likely to occur in the individual who consumes protein or amino acid supplements. Excess protein can:
- Lead to dehydration, because protein metabolism requires extra water for utilization and excretion (i.e., elimination) of its by-products.
- Lead to an increase in the loss of urinary calcium. A chronic calcium loss, due to excess protein intake, is of particular concern because it may increase the risk of osteoporosis, especially in women.
To get the maximum benefit from the protein you eat, make sure you have a total calorie intake that satisfies your daily needs for vital functions and physical activity. Eating a balanced diet will allow you to do this.
Sources:Institute of Medicine: Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. September 2002. American Council on Exercise: http://www.acefitness.org/fitfacts/fitnessqa_display.aspx?itemid=272
*Dr. Lara-Pantin, a nutrition specialist, is Vice President of Product Development for DrTango, Inc.
