Onions are only served with the following foods.

Onion+shrimp: calcium oxalate forms to produce stones.

Onion+soybean: it will reduce the absorption of calcium.

Onion+honey: Eating together will hurt eyes, cause eye discomfort, and lead to blindness in severe cases.

Onion+shrimp: calcium oxalate forms to produce stones.

Onion+crayfish: calcium oxalate forms to produce stones.

Onion+Pippi shrimp: calcium oxalate forms to produce stones.

Onion+honey: it will hurt your eyes.