1. How much muscle you currently have. The more muscular you are, the more amino acids your body needs to maintain your current body composition periods.
2. Your activity level.. The more you exercise, the more protein your body needs.27
3. Your age. The older you get, the more protein your body needs to maintain muscle.28
4. Your hormones. If your body has high levels of growth hormone and insulin-like growth factor 1 (IGF-1), it will use protein more efficiently than someone with low levels. These hormones decrease as you age, which is one of the reasons why older adults need more protein periods.