There is an old saying: food is the paramount necessity of the people. As long as we are alive, we have to eat. However, only if the diet is reasonable and scientific, can it promote the health of our body. On the contrary, if you eat improperly, it will cause harm to the body. In the following passage, we will introduce eight kinds of food, which you should not eat too much.

1. Preserved duck egg
During the working process of preserved duck egg, a certain amount lead should be added in. If you eat too much preserved duck eggs, it can cause lead poisoning, and may even lead to calcium deficiency.

2. Stinky tofu
During the fermentation process, stinky tofu is easily contaminated by microbes. At the same time, it contains a large number of volatile hydrogen sulphide, which is a kind of decaying substance after the protein is decomposed in the body. Therefore, eating too much stinky tofu is harmful to human body.

3. Deep-fried dough sticks
Deep-fried dough sticks contain alum, which is a kind of inorganic acid with aluminum in it. If you eat deep-fried dough sticks everyday, the aluminium will be difficult to be discharged through the kidney, thus it will cause harm on the brain and nerve cells, and even lead to senile dementia.

4. Instant noodles
Instant noodles contain food color and preservative, which are not beneficial to the body if you eat too much.

5. Pork liver
1000 grams of pork liver contain more than 400 milligrams of cholesterol. According to experts, excessive intake of cholesterol not only will lead to arteriosclerosis, but also can aggravate cardiovascular disease.

6. Roast beef and mutton
When the beef and mutton are toasted and smoked, they will produce some harmful substances such as benzopyrene, which is a kind of carcinogen. Although roast beef and mutton taste delicious, for the health of your body, do not eat too much of these foods.

7. Pickled vegetables
Pickled vegetables not only lack of nutrition, but also contain a kind of carcinogenic substance--nitrosamine. As a result, experts suggest people should eat more fresh vegetables in daily life, and eat less pickled food.

8. Monosodium glutamate (MSG)
One person should not take in more than 6 milligrams of MSG every day. If you take in too much, it can increase the content of glutamate in the blood, and inhibit the utilization of calcium and magnesium by the body. This not only can cause symptoms such as short-term headache and nausea, but can also bring adverse effect on human reproductive system.