Dementia is difficult to prevent because what causes it often is not known. However, people who have vascular dementia may be able to prevent future declines by lowering their risk of heart disease and stroke. Even if you don't have these known risks, your overall health can benefit from these strategies:

• Treat or prevent high blood pressure. To do this, you may need to take medicines or you may be able to get results from lifestyle changes such as losing excess weight, exercising, limiting alcohol, cutting back on salt, quitting smoking, and eating a low-fat and low-saturated-fat diet. For more information, see the topic High Blood Pressure (Hypertension).
• Do not smoke.
• Stay at a healthy weight. This also reduces your risk of diabetes, another risk factor for dementia.
• Keep your cholesterol in the normal range. Total cholesterol should be less than 200 mg/dL. For more information, see the topic High Cholesterol.
• Get regular exercise. For best results, try to exercise for 30 to 60 minutes at least 5 times a week. It does not need to be done all at one time; it can be a combination of exercises, such as a daily morning walk and an afternoon walk.
• Stay mentally alert by learning new hobbies, reading, or solving crossword puzzles.
• Stay involved socially. Attend community activities, church, or support groups.

In people who already have had a stroke, treating high blood pressure reduces the risk of another stroke by 20%. Taking aspirin to prevent blood clots lowers the risk of another stroke by 17%.¹⁶ For more information on how to reduce your risk for stroke, see the topic Stroke.

Some older people develop symptoms that look like dementia but are the result of taking medicines that don't work well together. You may be able to avoid this problem by making sure your doctor knows about all medicines-both prescription and over-the-counter-and all vitamin, herbal, and dietary supplements you take.

Research

• One study found that older adults who regularly participated in leisure activities that required mental effort reduced their risk of dementia. Reading, playing board games, playing a musical instrument, and dancing were all found to be helpful, but most likely any hobby that keeps the brain active would be beneficial.¹⁷
• Some evidence suggests that light to moderate alcohol use (1 to 6 drinks a week) may reduce the risk of dementia in older people.^{18, 19} Since heavier drinking can cause dementia, alcohol use is a widely debated issue.
• One study found that people age 50 or older who took cholesterol-lowering medicines called statins reduced their risk of developing dementia.²⁰ More recent studies have not found that statins reduce the risk of dementia. But these studies were of people age 65 and older.^{21, 22} Whether taking statins might help people who start them at a younger age is not known.
• Hormone replacement therapy (HRT)-a combination of estrogen and progesterone-was once believed to provide protection from dementia or cognitive impairment. But the Women's Health Initiative found that HRT actually increased the risk for Alzheimer's disease and other dementias in women age 65 and older who took it for more than 4 years.⁵ Estrogen alone (estrogen replacement therapy) had similar effects.⁶ Whether either of these therapies might help reduce the risk of later dementia when used around the age of menopause is not known.⁷