Protein digestion doesn't happen all at once, and it can take up to 90 minutes to be fully absorbed by the small intestine. The body can start to digest protein within 15 to 30 minutes.
Many people opt for whey protein as it is absorbed into the body faster than other types of protein, which makes it ideal for bodybuilders. If more than 15 grams of protein are consumed in an hour, any protein past the initial 15 grams may not be absorbed and may become waste product instead. Protein is essential for muscle growth and post-exercise muscle recovery.