How much protein can your body use at one time for building muscle?

Q. I am a 37 year-old man who is getting back into body building and considering a protein supplement. How many grams of protein can the body digest and use at a time?

A. Body builders and people who exercise vigorously rarely need more than 0.75 grams of protein per pound of body weight daily. For a 180-pound man, that would be a total of 135 grams of protein per day.

A person who rarely exercises needs half that amount - about 0.37 grams per pound of body weight per day.

Regarding how much protein can be digested and absorbed in the intestine at one time, there is no specific maximum amount. However, the body will only use what it needs (0.75 grams per pound of weight for a body builder).

To build muscle, the maximum amount of protein to take at one time is 25 to 30 grams. Additional protein can be absorbed and used for other bodily functions.

When we eat high amounts of protein, the body (especially the kidneys) needs to work hard to get rid of all the nitrogen in proteins.

Too much dietary protein can have adverse consequences. These include:

• dehydration
• gout
• kidney stones.

A question body builders and athletes often ask is whether the type of protein matters. There is no definite proof that one type of protein builds more muscle than any other type. Fish, vegetable, bean, and nut proteins are healthier. They don't contain the saturated fats that accompany animal proteins.

If you are looking for a protein supplement, one that contains a mixture of casein and whey is a reasonable choice. They are broken down into peptides (small pieces of protein) and amino acids, which are more easily absorbed.

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