Spinach contains a lot of oxalic acid, which can easily combine with calcium or other metal ions to form insoluble substances. Preserved eggs contain a lot of iron and calcium, which is easy to cause digestive difficulties after eating with spinach.

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Nutritional value of spinach

1, spinach leaves contain chromium and an insulin-like substance, which is very similar to insulin and can keep blood sugar stable.

2. Spinach contains a lot of beta carotene, vitamin B6, folic acid and potassium, which has a positive effect on preventing cardiovascular and cerebrovascular diseases.

3. Spinach contains protein, carbohydrate, fat, carotene, vitamin C, vitamin A, vitamin K, vitamin B, calcium, phosphorus, iron, potassium, magnesium and other nutrients. Among them, carotene and vitamin K are rich. Among vegetables, spinach contains more protein.