This is what happens to protein when you overcook it

Overcooking protein-rich foods like chicken, fish, eggs, and paneer can impact both their nutritional value and texture. When heated excessively, proteins undergo denaturation, making them harder for the body to digest. However, this doesn't make the food unhealthy or protein-free. The primary issues arise from overcooking for extended periods at high temperatures, which can cause proteins to pack tightly and reduce accessibility of amino acids to digestive enzymes.

This can affect the efficiency of protein absorption. Texture-wise, overcooked chicken or fish can become dry and tough, while eggs may become rubbery. Methods involving very high temperatures, prolonged frying, grilling, or charring can introduce additional harmful compounds like heterocyclic amines and polycyclic aromatic hydrocarbons, further diminishing nutritional quality and safety.

To preserve both nutritional and sensory quality, cooking should be done thoroughly but not overdone, using moderate heat and stopping once the food is properly cooked.