So let's say you just can't stomach organ meats, even though you have really, really tried. Are there any good substitutes out there, like say foods that will provide you the same nutrients or supplements that you can take that will have the same effect?
I don't know if it would be as effective as eating organ meats but I used to take something called Simplex F, which seemed to have a bit of every organ, it might be just for girls though, I think I remember it saying ovary on the ingredient list. I know I've seen other brands with an organ sampling, usually claiming to be "synergistically blended" for adrenal or thyroid support. I take one for thyroid sometimes.
There are also liver pills you can take. Most I've seen are from grassfed cows in Argentina, they're cheap too as far as supplements go. You can also make your own capsules of any organ meat you think you're lacking, just slice it thin, dry it out in the oven, grind it up, and pack it into capsules. Tastebuds completely bypassed.
If you are trying to get the vitamin D and A I think you could get that from grassfed butter and cod liver oil.
Shellfish. They're nutritionally flabbergasting. Calorie for calorie, oysters are pretty comparable to liver -- super high in iron, B12, copper, zinc, selenium, vitamin D, etc. Mussels aren't too shabby either.
Well the main thing you want from liver is vitamin A, so take a 10kiu retinol supplement daily and you got that covered.
For the b vitamins/copper eat some tubers/fruit.
If you feel liver has some special property you could get powdered liver which is supposedly very rich in Cytochrome p450. Its pretty easy to down in milk/water or with some food.
How you cook organ meats and seafood is even more important. You can nutritionally destroy salmon by steaming it because it allows for PUFA putrifaction to increase the six to three ratio of the fish. Seems counterintuitive until you understand the biochemistry of cooking.
Samething holds true of liver and oysters.