There have been reports indicating that high protein diets can be detrimental to your health. These concerns have no scientific substantiation whatsoever. Learn more
How Much Protein Is It Safe For Me To Take?


A study conducted by the International Society of Sports Nutrition reviewed the position stand of protein and exercise for trained individuals. The article outlined seven specific points relating to the intake of protein for healthy, exercising individuals. The Recommended Daily Allowance (RDA) of protein according to U.S. government standards is 0.8 gram per kilogram (2.2 pounds) of ideal body weight for the adult.

This protein RDA is specified to meet the majority of the populations protein needs. Since athletes and trained individuals have a higher demand for nutrients-particularly protein-it was necessary to reevaluate the current needs of this demographic.


The following points have been approved by the Research Committee of the Society.

Vast research supports the contention that individuals engaged in regular exercise training require more dietary protein than sedentary individuals.
Protein intakes of 1.4 - 2.0 g/kg/day for physically active individuals is not only safe, but may improve the training adaptations to exercise training.
When part of a balanced, nutrient-dense diet, protein intakes at this level are not detrimental to kidney function or bone metabolism in healthy, active persons.
While it is possible for physically active individuals to obtain their daily protein requirements through a varied, regular diet, supplemental protein in various forms are a practical way of ensuring adequate and quality protein intake for athletes.
Different types and quality of protein can affect amino acid bioavailability following protein supplementation. The superiority of one protein type over another in terms of optimizing recovery and/or training adaptations remains to be convincingly demonstrated.
Appropriately timed protein intake is an important component of an overall exercise training program, essential for proper recovery, immune function, and the growth and maintenance of lean body mass.
Under certain circumstances, specific amino acid supplements, such as branched-chain amino acids (BCAAs), may improve exercise performance and recovery from exercise.


Protein Intake Recommendations


The RDA for healthy adults (0.8 g/kg body weight per day) was created to allow for an individual's differences in protein metabolism-since people's metabolic rate can vary due to numerous factors. That recommendation for protein intake covers that vast majority of society-approximately 97.5%- which may be adequate for non-exercising individuals. Since exercise breaks down additional foodstuffs coming from protein, carbohydrates and fats, trained individuals require more calories-especially coming from protein to accommodate recovery and muscle maintenance.


Most studies related to protein requirements use nitrogen balance assessments and amino acid tracer studies. This has one primary disadvantage for trained individuals because nitrogen balance studies may underestimate the amount of protein needed for optimal performance related to exercise. All athletes whether endurance, resistance, or any other form of training require additional protein to fuel their metabolism.

For endurance training individuals, recommended protein intakes range from of 1.0 g/kg to 1.6 g/kg per day depending on the intensity and duration of the endurance exercise, as well as the training status of the individual. Strength/power exercise is thought to increase protein requirements even more than endurance exercise, particularly during the initial stages of training and/or sharp increases in volume. Recommendations for strength/power exercise typically range from 1.6 to 2.0 g/kg/day.

Little research has been conducted on exercise activities that are intermittent in nature (e.g., soccer, basketball, mixed martial arts, etc.).

The position of the International Society of Sport Nutrition is that exercising individuals ingest protein ranging from 1.4 to 2.0 g/kg/day.

Protein Intake Recommendations:

Endurance Exercise: should ingest levels at the lower end of this range

Intermittent Activities: should ingest levels in the middle of this range

Strength/Power Exercise: should ingest levels at the upper end of this range.


Safety Of Protein Intakes Higher Than RDA


Within the media there has been widespread reports that high levels of protein intake puts heavy stress on the kidneys. There has been other reports indicating that high protein diets increase excretion of calcium-leading to an increased risk of osteoporosis. Both of these concerns have no scientific substantiation whatsoever. Most of the cited sources relate to studies done on animals and patients with co-exiting renal (kidney) disease. For healthy individuals-with no disease or impairment-higher levels of protein intake for exercising individuals are safe, and desired for optimal performance.



Protein Quality And Common Types Of Protein Supplements


To obtain supplemental dietary protein, exercising individuals often ingest protein powders. Powdered protein is convenient and, depending on the product, can be cost-efficient as well. Common sources of protein include milk, whey, casein, egg, and soy-based powders. Different protein sources and purification methods may affect the bioavailability of amino acids. Bioavailability can be best defined as how well your body breaks down and absorbs protein in the blood stream.

Commercially, the two most popular types of proteins in supplemental form are whey and casein. The differences in the digestibility and absorption of these protein types may indicate that the ingestion of "slow" (casein) and "fast" (whey) proteins differentially mediate whole body protein metabolism due to their digestive properties.

The recommendation of the International Society of Sport Nutrition is that individuals engaging in exercise attempt to obtain their protein requirements through whole foods. When supplements are ingested, we recommend that the protein contain both whey and casein components due to their high protein digestibility corrected amino acid score and ability to increase muscle protein accretion.