Parkinson’s disease is a degenerative disease of the central nervous system that occurs in middle and old age. The etiology of Parkinson’s disease is unknown. Since epidemiology is an important means of obtaining clues to the cause of the disease, many epidemiological investigations have been conducted in various ethnic groups around the world, and the preliminary conclusions are as follows: 1. There are racial differences in the onset of the disease, with whites being the highest, yellow next, and blacks the lowest. 2, the older the age, the higher the risk of Parkinson’s disease. The incidence of Parkinson’s disease is 10/100,000 at age 50 and jumps to at least 200/100,000 by age 80. 3. Industrialization and lifestyle do not affect the onset of Parkinson’s disease: The study found that, excluding the effects of population aging, there was no significant change in the incidence of Parkinson’s disease in the more than 40 years since 1935 to 1979. Such a conclusion basically excludes the possibility of industrialization or related lifestyle changes as a cause of Parkinson’s disease. 4. Gender: The majority of studies have concluded that men have a slightly higher prevalence than women, but several studies of the national population have found that the prevalence of men: women is as high as 3:1. Whether this is due to the influence of sex hormones or to some cultural factors (such as the tendency of men to engage in certain occupations) is not known. 5, smoking: most studies have confirmed that smoking is negatively associated with Parkinson’s disease, that is, smokers have a significantly reduced risk of developing Parkinson’s disease. 6, diet: this aspect is more controversial. Some scholars believe that coffee, niacin, nuts, pods and potatoes may reduce the risk of Parkinson’s disease; animal fat may increase the risk of Parkinson’s disease. In 1996, an autosomal dominant Parkinson’s disease family of Italian descent was discovered, which made genetics a hot spot in Parkinson’s disease research. Since then, alpha-synuclein has also been identified as an important component of the Lewy vesicles, a pathological marker of Parkinson’s disease, including sporadic Parkinson’s disease. Studies have shown that genetic factors may play an important role in Parkinson’s disease patients with onset before the age of 50, but in Parkinson’s disease patients with onset after the age of 50 (the majority of Parkinson’s disease patients with onset precisely after the age of 50), genetic factors do not play a role. 8, environmental toxins: Since the discovery of synthetic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) can cause Parkinson’s disease in the early 1980s, environmental toxins have been suspected as a possible cause of Parkinson’s disease. Since there is no natural MPTP in nature, scholars have been actively searching for other environmental factors that may cause Parkinson’s disease. Clinical epidemiological investigations have found that some environmental factors, such as rural residence, farming, drinking well water, and especially exposure to some pesticides (e.g., rotenone) and herbicides (e.g., paraquat), can increase the risk of developing Parkinson’s disease. Residues of an insecticide, Dieldrin, have even been found in the brains of Parkinson’s disease patients (not in normal human brains). However, to date, no environmental toxicant has been positively identified as the cause of Parkinson’s disease.