Some people have habits of smoking and drinking alcohol, so can these habits also lead to the development of Alzheimer’s disease? Different people have different opinions. There is no unified conclusion on the concern of smoking, alcohol consumption and the onset of Alzheimer’s disease. Some previous studies have found that smoking can reduce the onset of Alzheimer’s disease, the reasons for which are not clear. Some believe that nicotine in cigarettes has a protective effect on the brain’s nervous system, while others believe that smoking can lead to diseases in other systems of the body, thus causing people to lose their life expectancy early, so that their chances of developing Alzheimer’s disease are reduced. Later studies have found that smoking increases the prevalence of dementia. The prevailing view now is that there is no evidence that smoking is protective against Alzheimer’s disease. The relationship between alcohol consumption and dementia is also not generalizable. Studies have shown that small amounts of moderate amounts, especially wine, will reduce the occurrence of dementia because of the blood-boosting effect that can be achieved; whereas large amounts of alcohol will increase the damage to brain cells, and this can become a risk factor for the development of dementia. In addition, alcohol overdose itself can also lead to the development of alcoholic dementia. There is also a habit that many people have, which is drinking tea. We all know that tea has theophylline and tea polyphenols, both of which can dilate cerebral blood vessels and reduce platelet aggregation, and they also have antioxidant effects, which can reduce the occurrence of vascular events, and will also slow down the aging and decline of brain cells, thus arriving at reducing the occurrence of dementia. In conclusion, drinking tea is a beneficial lifestyle for the development of Alzheimer’s disease.