It also contains essential amino acids that are not made by the body but must be obtained from food sources. (wellnessmama.com)
The primary source of magnesium is from our diet as it can be obtained from foods like green leafy vegetables, nuts, spices, beans, whole grains, and cocoa. (ahealthblog.com)
The «essential» bit means we need to obtain them from food because our bodies are unable to make our own. (eat-spin-run-repeat.com)