First, long-term consumption of vegetable oil.
It has been determined that the peanut and corn oil are easily mixed with aflatoxin, which is a kind of strong carcinogen. If the cottonseed oil has not been processed, it may contain gossypol, which will cause poisoning. The erucic acid in rapeseed oil is not conducive to the health of people who suffer from high blood pressure and heart disease. Therefore, do not take in too much vegetable oil in daily diets. The correct proportion between vegetable oil and animal oil should be 1 to 0.3.

Second, using dried shrimp to make soup directly.
When the dried shrimp is processed, it is easily infected with a number of carcinogens. If using the dried shrimp to make soup directly, it is not conducive to human health. Experts suggest that you can change the water after the dried shrimp has been boiled for a few minutes, or add 1 to 2 tablets of vitamin C in the soup, which can block the synthesis of carcinogens in the body.

Third, eating too many soybean products.
Experimental results show that excessive intake of soybean protein can resist 90% of the normal amount of iron absorption, which may lead to iron deficiency anemia, showing different degrees of dizziness, fatigue and other symptoms of anemia. In addition, soybean products are rich in methionine. If people take in a lot of soybean products, the methionine, under the action of the enzyme, will change into homocysteine, which will damage the artery wall cells, leading to the hardening of the arteries.

Fourth, adding too much seasoning in the dish.
Pepper, cassia, clove, fennel, ginger and other natural spices have certain mutagenicity and toxicity. Eating too much of these seasoning can cause the distortion of human cells, leading to the formation of cancer, and it may cause some side effects such as dry mouth, sore throat, lassitude, insomnia and so on. What's more, it can also induce hypertension, gastroenteritis and many other pathological changes.

Fifth, adding sugar in the cold dishes.
When making cold dishes, some people like to add in some sugar, so as to improve the taste of the dishes. In fact, such a habit is very harmful to human health, because there are a large number of mites existing in granulated sugar, soft sugar or other sweet food. If the contaminated sugar has not been processed through heat treatment, these mites will enter into human body along with the food and stay in the gastrointestinal tract. These mites will release a great amount of toxins, which may stimulate the intestinal wall and cause spasm, thus leading to abdominal pain.