"How Much Protein Do I Need?"

The RDA guideline for protein is 0.8 grams per kilogram of bodyweight per day. So if you weigh 190 pounds (86 kilograms) you'd need about 69 grams of protein. That's fine for inactive couch potatoes, but is that enough for athletes, bodybuilders, and lifters? No. In fact, it's not even close.

Lifters and athletes concerned with their performance or physique require more protein than what's recommended by the RDA. It's a myth that the RDA protein recommendations are adequate for ass-kicking individuals.

Here's Why: Nitrogen Balance

RDA protein recommendations are too low for certain groups. Those recommendations were never intended for people attempting to enhance performance, maintain, or gain muscle. (In fact, a higher protein intake may have positive benefits regarding different health ailments including obesity, type-2 diabetes, osteoporosis, heart disease and muscle wasting.)

The RDA guideline reflects the minimum daily needs of protein required to maintain short-term nitrogen balance in healthy, moderately active people. Nitrogen balance compares the amount of nitrogen coming into the body (from dietary protein) to the amount being lost. It's often used as a measurement of protein balance since protein is 16 percent nitrogen.

If you're consuming the same amount of nitrogen that you're losing, you're in nitrogen balance. If you're consuming more than you're losing, you're in positive nitrogen balance. If you're losing more than you're consuming, you're in negative nitrogen balance and are losing protein. Not good.

Nitrogen balance studies often involve examining urinary nitrogen levels. About 90 percent of the nitrogen in urine is urea and ammonia salts – the end products of protein metabolism. The remaining nitrogen is accounted for by other nitrogen-containing compounds.

This nitrogen balance method is useful, but it has problems: Urine collections tend to underestimate nitrogen losses, dietary intake tends to be overestimated, miscellaneous skin and hair losses are prone to error, and the response to increased protein intake varies tremendously.

The Science

1. In a review published in the International Journal of Sports Nutrition, researchers concluded, "Those involved in strength training might need to consume as much as 1.6 to 1.7 grams of protein per kilogram per day (approximately twice the current RDA) while those undergoing endurance training might need about 1.2 to 1.6 grams per kilogram per day (approximately 1.5 times the current RDA)."
2. Another article published in Nutrition & Metabolism argued that the dietary guidelines should be improved and reflect new understandings about protein requirements. According to researcher Donald Layman, "A growing body of research reveals that dietary protein intakes above the RDA are beneficial in maintaining muscle function and mobility." Diets with increased protein have been shown to improve health when it comes to treatment or prevention of obesity, type-2 diabetes, and other conditions.
3. A review published in the International Journal of Sport Nutrition and Exercise Metabolism was conducted to evaluate the effects of dietary protein on body composition in energy-restricted resistance-trained athletes, and to provide protein recommendations for these athletes.

The researchers concluded that "...the range of 2.3 to 3.1 grams per kilogram of FFM (fat free mass) is the most consistently protective intake against losses of lean tissue." So, for every kilogram on your body that's not fat, you should be consuming 2-3 grams of protein in order to preserve lean tissue. So if you have 190 pounds of lean tissue, up to 258 grams of protein would be optimal for you.