I'm not clear on what concern is behind your question. My normal practice is to make bone broth stews and chill/reheat in repeated cycles. As long you eat/drink the whole thing you get the nutrients whether they are in the broth or still in the solid food. Some people, though, don't enjoy the flavors/textures of re-heated food while others (Me!) like them better. In most families, there are some who love leftovers and some who hate them.
For nicer cuts of meat such as muscle-beef/turkey/duck I will frequently eat them cold out of the fridge but I definitely prefer my vegetables and broth re-heated. I also eat lots of leafy salads too.
Re-cooking some foods like broths and meat soups is a time-honored way of increasing the time you can store them before they spoil (boiling for at least ten minutes is re-cooking a soup, as opposed to warming it up to make it more palatable). In this sense there is a definite advantage to re-cooking some foods. As far as reheating goes, however, I can't see any reason to re-heat a left-over or to not reheat it except for your own personal preferences.
i only eat meat for the 20+ amino acids that are relatively heat stable, so i cook and recook all meat products for well documented safety concerns. i get my nutrition from raw vegetables and raw fruit.