Understanding Food Compatibility and Incompatibility
In daily life, not all foods can be consumed together. "Proper pairing benefits health; improper pairing causes illness." In other words, foods can also "clash."
Tannins and Protein Clash: Consuming fruits like grapes, hawthorns, pomegranates, or persimmons alongside seafood may lead to nausea, bloating, abdominal pain, and diarrhea. This is because tannins in these fruits react with proteins in seafood, forming insoluble precipitates that are hard to digest. Thus, after eating seafood, one should wait at least four hours before consuming such fruits. Similarly, avoid drinking tea right after eating meat.
Fiber and Oxalic Acid vs. Iron: Animal liver, egg yolks, and soybeans contain abundant iron and should not be eaten with high-fiber vegetables like celery, radish, sweet potatoes, nor with high-oxalic-acid greens like amaranth, purslane, or spinach. Both fiber and oxalic acid hinder iron absorption from these foods.
Protein and Sugar Clash: Lysine in milk reacts with sugar under high heat, destroying amino acids. This is why eggs and sugar should not be boiled together. However, if milk is boiled and eggs are cooked first, then cooled slightly before adding sugar, this issue does not occur.
Carotene and Acetic Acid Clash: Do not add vinegar when stir-frying carrots, as acetic acid destroys carotene. Similarly, avoid using vinegar to cook other carotene-rich vegetables like snow cabbage, spinach, or Chinese mustard greens.
Oxalic Acid vs. Calcium and Magnesium: Do not eat tofu with spinach. Tofu contains magnesium chloride and calcium sulfate, while spinach contains oxalic acid. When combined, they form insoluble calcium oxalate and magnesium oxalate—white precipitates that cannot be absorbed by the body. This not only impairs calcium absorption but may also contribute to stone formation.