Skip Navigation Bar
NIH MedlinePlus the Magazine, Trusted Health Information from the National Institutes of Health

Alzheimer's Disease

What Do We Know About Preventing Alzheimer's?

How Alzheimer's Changes the Brain

Healthy brain compared to Alzheimer's-affected brain

Currently, the most definite diagnosis of Alzheimer's disease is made after death, by examining brain tissue for plaques and tangles. The brain also shrinks (See illustration). Scientists now realize that many other cellular changes also occur in the brain, such as inflammation and blood vessel disease.

Unlike age and genetics, certain health and lifestyle factors associated with Alzheimer's disease risk may be controlled. Scientists are exploring prevention strategies to determine whether or not things like exercise, diet, and "brain games" can help delay or prevent Alzheimer's disease and age-related cognitive decline. They are also investigating how certain medical conditions, such as high cholesterol, high blood pressure, and diabetes, influence risk for cognitive impairment.

So far, studies have not demonstrated that, over the long term, health or lifestyle factors can prevent or slow Alzheimer's disease or age-related cognitive decline. Similarly, clinical trial results do not support the use of any particular medication or dietary supplement to prevent these conditions.

Promising research in these areas is under way. The NIA supports more than 30 clinical trials, including many that are investigating possible ways to prevent or delay Alzheimer's disease or age-related cognitive decline. Learn more about what the research shows about preventing Alzheimer's at

Latest NIH Research

  • NIH's National Institute on Aging (NIA) leads the federal government's research efforts on AD. Scientists at NIA-supported Alzheimer's Disease Centers and other research institutions conduct clinical trials and carry out a variety of studies, looking at the causes, diagnosis, and management of AD. NIA also sponsors the Alzheimer's Disease Cooperative Study, a group of leading AD researchers throughout the United States and Canada who conduct clinical trials on promising AD treatments.
  • Today, at least 70,000 volunteers are urgently needed to participate in more than 150 active clinical trials and studies in the United States that are testing ways to understand, treat, prevent, or cure Alzheimer's disease. All kinds of people, including healthy volunteers, are needed.
  • One current trial, Anti-Amyloid Treatment in Asymptomatic Alzheimer's Disease Trial, or A4, is among a new generation of clinical trials testing therapies that might prevent, or at least delay, Alzheimer's disease in cognitively normal people at risk for the brain disorder. Previous trials have tested a variety of drugs in people who already had Alzheimer's dementia, but results have shown no significant improvement in cognition or daily functioning. This study is currently seeking volunteers to participate. Visit:
  • To learn more about participating in trials or studies, read Participating in Alzheimer's Research: For Yourself and Future Generations You can also contact the NIA Alzheimer's Disease Education and Referral (ADEAR) Center at 1-800-438-4380 or go to to search currently available research studies.
  • You can also ask your doctor, who may know about local research studies that may be right for you, or sign up for a registry (such as the Alzheimer's Prevention Registry, or a matching service (such as ResearchMatch,, or the Alzheimer's Association's TrialMatch, to be invited to participate in studies or trials when they are available in your area.
Read More "Living with Alzheimer's Disease" Articles

Living with Alzheimer's Disease / What Are the Signs of Alzheimer's Disease? / Preventing Alzheimer's Disease / Quiz: Alzheimer's Disease / Treatment

Winter 2015 Issue: Volume 9 Number 4 Page 11