The reason for this is the following：
1, apple belongs to flat fruit, and flat and cold fruit is beneficial to reduce fever and increase rich nutrition. Eating apples for children with fever helps to replenish water and play a role in cooling down and keeping out the cold.
2. Apple is also rich in vitamin C, which has the function of clearing away heat and toxic materials and can enhance the function of human immune system. In addition, eating apples and honey together, or boiling water with apples and honey, is very effective in treating sore throat.
Extended data:
Precautions for eating apples:
1. Apples should not be eaten with seafood.
Apples contain tannic acid. Eating with seafood not only reduces the nutritional value of seafood protein, but also tends to have symptoms such as abdominal pain, nausea and vomiting. Similarly, other fruits with much tannic acid, such as strawberries, bayberries, persimmons, pomegranates, lemons and grapes, should not be eaten with seafood.
2, eat apples, don't bite the apple core.
Apple core contains a small amount of harmful substance hydrocyanic acid. A large amount of hydrocyanic acid deposited in the body will lead to dizziness, headache, increased respiratory rate and other symptoms, which may lead to coma in severe cases. But don't worry too much, the hydrocyanic acid in apples mainly exists in the stone, not in the pulp.
3. Be careful to wax apples
Many apples use excessive growth promoters, erythropoietin and swelling agents in the growth process, or use excessive preservatives in storage, and even use colorants, waxing, bleaching and dyeing in sales to satisfy consumers' psychology of "judging a book by its appearance". These poisonous fruits have become public hazards that seriously threaten people's health.
References:
People's Daily Online: What fruit should I eat if I have a cold? These 8 kinds of fruits should not be eaten on an empty stomach.
People's Daily Online: Three taboos should be kept in mind when eating apples in autumn.