Some people think that the side effects can only be caused by drugs and medical treatments. The daily foods we eat can supplement essential nutrients and increase the weight for us without any other dangers. In fact, the foods in our daily life can also cause side effects among us. Generally speaking, the side effects include ten aspects, namely, peculiar smell, acne, allergy, candidiasis, heartburn, high cholesterol, renal calculus, decreasing memory, edema and headache. 

According to the medical research, the intake of red meet can produce peculiar smell inside the human body. The saturated fatty acid can increase the subcutaneous fat, which can stimulate the production of acne. The scientists have proved that the frequent intake of milk can cause acne. Allergy is the first side effect caused by the foods. Most foods can cause allergy, such as milk, eggs, peanut, fish and soy bean. The excessive reproduction of yeast inside the human body can cause the infection of saccharomycetes. The intake of foods can affect the normal level of yeast to cause the candidiasis. Sugar, vinegar and carbohydrates can induce this disease. Various kinds of foods can cause heartburn and stimulate the secretion of gastric juice, such as tomato, vinegar and chocolate. The high intake of animal foods can increase the cholesterol inside the human body and raise the risks of getting heart disease, as the content of cholesterol inside the animal foods is rather high. Therefore, people should not eat the animal foods like animal liver and eggs excessively. What's more, the foods containing high animal protein and low fibers can cause the formation of renal calculus. Therefore, people should decrease the intake of the foods containing salt, animal protein and oxalic acid and increase the absorption of calcium in daily life. At the same time, the intake of the foods containing too much copper should also be decreased, as the excessive supplementation of copper can affect the normal memory of people. The edema and headache can be respectively caused by the excessive intake of salt and the excessive intake of amino acids tyramine and tolbutamine. The foods like smoked foods should be avoided as far as possible.

In short, people should learn to understand the characteristics of various foods so as to eat foods in a healthy way. The side effects can not be completely avoided. What people can do is to try their best to reduce the harms.