Early clinical data have begun to suggest that estrogen therapy may lessen the devastation of Alzheimer's disease. Women on estrogen therapy who develop Alzheimer's disease tend to develop the disease more slowly, at a later age, and with less severity. It's not yet known whether you can start estrogen therapy at the time Alzheimer's disease is diagnosed and still obtain any significant benefit. Studies that have compared women taking tamoxifen to women taking placebo, however, showed similar reports of memory loss in both sets of women. Fatigue, anxiety, and depression have a potent effect on memory too.
Chemotherapy can affect memory.
Radiation to the breast area has no effect on short-term memory or other mental functions, but radiation to the whole brain for metastatic disease can have a profound effect. Just as it can affect anything else, our genetic makeup may influence how our memory functions. New information about the brain indicates that contrary to past belief, brain cells are not fixed in number. No matter how old you are you can still grow new brain cells. After menopause, many women begin a slow but steady weight gain.