Estrogen is a substance found in women’s bodies to maintain their normal physiological functions. It is better known for its role in women’s reproductive function, but in fact it also has a role in the cognitive function of the brain, affecting people’s learning and memory. Many studies have found that the relationship between estrogen and Alzheimer’s is still relatively strong. As we mentioned earlier, the prevalence of Alzheimer’s disease is higher in women than in men, and this is also related to the fact that women’s estrogen levels decrease as they age. Some studies have found that postmenopausal women who use external estrogen replacement therapy have fewer Alzheimer’s than older women who do not use estrogen. There are also some studies that have also found that women who have had their ovaries removed often show some memory impairment, and the removal of the ovaries means that there is less estrogen, which also suggests that there is a relationship between the decline in estrogen and the decline in memory. Therefore, a lot of people have now started to use estrogen to treat and prevent Alzheimer’s disease. In addition, there are some endocrine diseases, such as hypothyroidism and parathyroidism, which may cause dementia.