We know that the nutrition of what we eat has to do with what that food consumed for growth and functioning and the resulting composition (this is not limited to animal products). Maybe I missed this somewhere but I'm curious if anyone has any insight on how reliable our nutritional information is. When you consider the difference of environments where things are grown and also the different methods used to produce food, it's hard to believe that the resulting foods would not have substantial nutritional variations. We have profiles for beef, grass-fed beef, pork, turkey, lamb, etc. but how varied are the sources of the information? We know that non-ruminants tend to be high in omega 6, but how much of the information is determined by the animal and how much is determined by its diet? Even something like brazil nuts. We know that brazil nuts are high in selenium and that the reason they are high in selenium has to do with the composition of the soil and environment they are grown in. Is it possible that nutrient information from brazil nuts on a particular farm 10 years ago is no longer accurate because of the toll farming takes on the soil?
Does anyone have any idea what kind of nutritional variance there might be between the cheapest ground beef you can find and the most expensive organic (but still not grass-fed) ground beef? Or might we even be getting into a different composition of food due to the processing that cheap food tends to undergo?
Your question is something I've been wondering about also. For example, when we read a nutrition label on a package of plain frozen spinach, where does the nutritional content info come from? When was the nutritional content measured, last year or last decade?
I know our soil is being depleted, so is our food as nutrient dense as it used to be?