Can your body only absorb 30 grams of protein at a time?
You may have heard that your body needs 20-40 grams of protein at each meal in order to optimize muscle protein synthesis (this is the body’s system of rebuilding, synthesizing, and repairing skeletal muscle). Overall protein intake recommendations range from about 1.3-2.2 grams/kilogram of body weight per day are usually recommended throughout the sports nutrition scientific literature.
Splitting up protein intake into regular meals, in some studies, seems to be more effective than eating very little protein and one meal and making up the rest at another meal.
Does this mean you should only eat 20-30 g of protein per meal?
No! But you can! You can also eat more than that.
There seems to be some confusion around this concept: the recommendation to eat around 20-30 grams of protein per meal DOES NOT MEAN your body can only absorb or utilize that much! It simply means, according to current research, this seems like a good distribution pattern for eating protein throughout the day if you are focused on muscle building and recovery.
Some studies have shown that eating about 30 grams, or around 2-3 grams of leucine, was adequate to stimulate muscle protein synthesis. Beyond 40 grams did not further stimulate muscle protein synthesis. This doesn’t mean it is wasted or your body can’t absorb more; this just means it seems like the useful threshold to stimulate muscle protein synthesis.
What happens if I eat more than 30 g of protein in one meal?
Your body can actually absorb more than 30 grams, and theoretically can absorb an unlimited amount. Your body uses protein for a variety of processes–not just skeletal muscle building and repair. Your gut actually uses quite a bit of protein just to function. Your organs use protein. Even your bones use protein! If you eat more than your body needs at a given moment, some protein is broken down into amino acids and circulates as an “amino acid pool” –sort of like raw materials your body can use to build proteins later for various purposes. If there is a lot of excess protein it can be excreted in stool.
So don’t worry if you eat more than 30 grams of protein in one meal. It likely will not be wasted. Your body is smart and resilient; it knows how to use nutrients you give it!
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