What is the difference between complete and incomplete protein?

Nikkiey explains on Ep. 338 that there are 20 amino acids in total, and nine are essential because your body cannot make them. Complete proteins give you the full set of building blocks for muscle repair, strength and body recomposition. Her list: chicken, turkey, beef, eggs, fish, Greek yogurt, cottage cheese and whey. Incomplete proteins such as nuts, seeds, rice, oats, beans and lentils still count as protein and still have value. They are just missing one or more of those key pieces.

There is some nuance between episodes. On Ep. 306, registered dietitian Abbey Sharp says the body keeps a reservoir of amino acids, so you don't need to combine specific plant proteins at the same meal. Eating a variety of protein sources is generally enough. Her exception is protein powder: whey has a good amount of leucine, the trigger amino acid for muscle protein synthesis, while most plant-based powders don't.

On Ep. 9, Nikkiey adds that whey and dairy-based powders are complete, but whole foods like chicken and meat also bring vitamins and minerals that processed powders and bars lack. Use those to fill gaps, not as most of your daily protein.