Meat and Fish
Why I think we should not eat Cooked Meat:
Meat eating animals have a SHORT digestive track and eat raw fresh meat.
A human has a LONG digestive track similar to a vegetarian animal.
Unfortunately, when meat is cooked the nutrient value is reduced drastically, It then clogs up the digestive system for several days, which means by eating protean rich alternatives to cooked meat which digest quickly, you could increase your nutrient intake drastically, potentially you could eat 3, 4, 5, veggie protean meals, in the time it takes to digest 1 meat meal.
Why I think we should not eat Fish:
Unfortunately the sea is full of man made materials and the poor fish spend their lives swimming around and eating pollution.
Why I think we should not eat Farmed Animals:
Farmed Animals including cows pigs chickens fish etc. are full of Antibiotics. If you have broken your immunity by modern living, the last thing you need is more chemicals!