National Institutes oF Health

National Institute on Aging

Preventing Alzheimer’s Disease 

What Do We Know?
Table of Contents

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

What Is Alzheimer’s Disease? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Risk Factors for Alzheimer’s Disease . . . . . . . . . . . . . . . . . . . . . . 3

Age . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Genetics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Understanding Scientific Findings in the News . . . . . . . . . . . . . . 6

The Search for Alzheimer’s Prevention Strategies . . . . . . . . . 8

Do Exercise and Physical Activity Protect the Brain? . . . . . . . . . . . 9

Does Diet Matter? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

What Is the Effect of Other Chronic Diseases? . . . . . . . . . . . . . . . 11

What About Vitamins and Dietary Supplements? . . . . . . . . . . . . 12

Is Keeping Your Brain Active Important? . . . . . . . . . . . . . . . . . . . . 14

How Might an Active Brain Prevent Alzheimer’s? . . . . . . . . . . . 15

Other Clues to Alzheimer’s Prevention . . . . . . . . . . . . . . . . . . 17

Hormones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Immunization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

The Path to Developing New Treatments . . . . . . . . . . . . . . . . 19

Finding Out Who Is At Risk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

So, What Can You Do? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Stay Healthy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Participate in Research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22

For More Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
1

Introduction

The news is full of stories about ways to stay healthy, eat right, 

and keep fit. Along with keeping their bodies healthy, people 

want to keep their minds sharp as they age. They also want to 

avoid brain disorders such as Alzheimer’s disease. 

Currently, Alzheimer’s disease has no known cure, but recent 

research results are raising hopes that someday it might be possible 

to delay, slow down, or even prevent this devastating disease. The 

National Institute on Aging (NIA), part of the National Institutes 

of Health (NIH) at the U.S. Department of Health and 

Human Services, is the lead Federal agency for research related 

to Alzheimer’s disease, mild cognitive impairment (MCI), and 

age-related cognitive decline. This booklet summarizes what 

scientists have learned so far and where research is headed. 

There is no definitive evidence yet about what can prevent 

Alzheimer’s or age-related cognitive decline. What we do 

know is that a healthy lifestyle—one that includes a healthy 

diet, physical activity, appropriate weight, and no smoking—

can maintain and improve overall health and well-being. 

Making healthy choices can also lower the risk of certain 

chronic diseases, like heart disease and diabetes, and scientists 

are very interested in the possibility that a healthy lifestyle 

might have a beneficial effect on Alzheimer’s as well. In the 

meantime, as research continues to pinpoint what works to 

prevent Alzheimer’s, people of all ages can benefit from taking

positive steps to get and stay healthy. (See “So, What Can You 

Do?” page 21.)
2

What Is Alzheimer’s Disease?

Alzheimer’s is an age-related brain disease that gradually 

destroys a person’s memory and thinking skills and, eventually, 

even the ability to carry out the simplest tasks. Alzheimer’s 

is the most common cause of dementia, a loss of cognitive 

functioning and behavioral abilities so severe that it interferes 

with a person’s daily life and activities.

Some mild forgetfulness is normal as people get older. But

sometimes memory or other thinking problems are serious—

they make it hard to do everyday things like driving, shopping,

or even talking with a friend. For example, 

people with MCI have memory or other 

thinking problems greater than normal 

for their age and education but can still 

function independently. MCI often, 

but not always, leads to Alzheimer’s 

dementia. Research is helping scientists 

better understand cognitive changes 

related to aging.
3

Risk Factors for Alzheimer’s Disease

Alzheimer’s is a complex disease that progresses over many 

years, like diabetes, heart disease, and other chronic conditions. 

A number of factors may increase or decrease a person’s 

chances of developing the disease. These risk factors include 

age, genetics, environment, and lifestyle. The importance of 

these factors may be different for different people. Some risk 

factors can be changed or controlled while others cannot.

Research shows that Alzheimer’s disease causes changes in 

the brain years and even decades before the first symptoms 

appear, so even people who seem free of the disease today 

may be at risk. Scientists are developing sophisticated tests 

to help identify who is most likely to develop symptoms 

of Alzheimer’s. Ultimately, they hope to prevent or delay 

dementia in these high-risk individuals. (See “Finding Out 

Who Is At Risk,” page 20.)

Age

Age is the best known risk factor for

Alzheimer’s disease. The risk of developing

the disease doubles every 5 years after 

age 65. Alzheimer’s becomes increasingly 

common as people reach their 80s, 90s, and 

beyond. These facts are significant because 

the number of older adults is growing. 

The U.S. Census Bureau estimates that 

Americans 65 and older will grow from 
4

13 percent of the population today to nearly 20 percent in 

2030. The group with the highest risk of Alzheimer’s—those 

older than 85—is the fastest growing age group. 

Genetics

The more researchers learn about Alzheimer’s disease, the 

more they realize that genes play an important role in its 

development. Scientists have found genetic links to both 

early-onset and late-onset Alzheimer’s disease. 

Early-onset Alzheimer’s is rare, accounting for only about 

5 percent of people with the disease. Its symptoms usually 

appear when people are in their 30s, 40s, and 50s. Most cases 

of early-onset Alzheimer’s are familial, caused by mutations 

(permanent changes) in one of three known genes inherited 

from a parent.

Late-onset Alzheimer’s disease, the most 

common type, typically becomes evident 

after age 60. The causes of late-onset 

Alzheimer’s are not yet completely understood, but researchers have identified 

several risk-factor genes. One of those 

genes, called apolipoprotein E (APOE), 

has three forms, or alleles (ε2, ε3, and 

ε4). One form, APOE ε4, increases a 

person’s risk of getting the disease. It is present in about 25 to 

30 percent of the population. However, carrying APOE ε4 does 

not necessarily mean that a person will develop Alzheimer’s, 

and people without APOE ε4 can develop the disease. 

Scientists have identified a number of other genes that may 

increase a person’s risk for late-onset Alzheimer’s. More studies 

are needed to assess the role these genes may play and to 

search for additional risk-factor genes. Knowing about these 
5

genes can help researchers more effectively test possible 

treatments and prevention strategies in people who are at risk 

of developing Alzheimer’s—ideally, before symptoms appear. 

Genetic testing cannot predict who will 

or will not develop late-onset Alzheimer’s. 

Currently, it is used only in research settings and for people with a family history 

of early-onset Alzheimer’s disease. This 

type of testing is not recommended for 

people at risk of late-onset Alzheimer’s. It 

is not conclusive, and its primary value at 

this point remains in research settings.

To Learn More

The NIA’s Alzheimer’s Disease Education and Referral 

(ADEAR) Center answers questions and provides free 

publications about Alzheimer’s disease and other types

of dementia. To learn more about genetics, see the 

“Alzheimer’s Disease Genetics Fact Sheet,”

www.nia.nih.gov/alzheimers/publication/alzheimersdisease-genetics-fact-sheet.
6

Understanding Scientific Findings in the News

Results of medical research studies appear in the 

headlines every day, raising and dashing hopes that 

cures for devastating 

diseases are right around 

the corner. It can be hard 

to know what to think 

about these study findings. 

Knowing the type of study 

and how it was conducted 

can help put the results 

into perspective.

An epidemiological study is 

an observational study that looks for common factors 

that might explain why or how a disease occurs in a 

certain group of people. Scientists gather information 

about people who are going about their daily lives, 

then analyze the data to see which behaviors or 

environmental factors are linked to a disease or other 

outcome. 

Epidemiological studies can’t tell us for sure that 

these factors actually cause or prevent the disease or 

health condition. Based on epidemiological studies 

of Alzheimer’s disease, scientists can report that a 

finding is or is not “associated with” Alzheimer’s, not 

whether it directly affects development or progression 

of the disease. 

For example, some epidemiological studies have 

found that people who exercise are less likely than 

inactive people to develop Alzheimer’s disease. But, 

people who exercise tend to be healthier in other 
7

ways than those who do not exercise, such as having 

lower rates of heart disease or eating a nutritious 

diet. We don’t know if their lower Alzheimer’s risk 

results from exercise, healthier eating, reduced risk 

of other diseases, a combination of those factors, or 

something else. So, we don’t know if exercising—

including how much and how often—will directly 

lower Alzheimer’s risk.

Scientists also use in vitro (test tube) studies and

animal studies to learn about disease. These types of 

studies control specific factors

that might influence a research

result. This approach allows

researchers to be more certain

about possible causes of a

disease. However, showing a

cause-and-effect relationship

in tissue samples or animals

does not mean that the

relationship will be the same

in humans. 

Randomized clinical trials are the best way to test 

directly in people the safety, effectiveness, and side 

effects of a medication or other treatment. In this 

type of research, some participants are randomly 

assigned to receive the intervention being tested—

say, medication or exercise—while others receive 

a placebo (such as an inactive pill or a control 

intervention). Any differences in outcome between 

the groups should result from the treatment rather 

than other differences between the participants.
8

The Search for Alzheimer’s Prevention 

Strategies

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 underway. 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. Observational studies 

have associated factors such as physical activity, blood pressure, 

and diabetes control with changes in risk. More research is 

needed to determine whether these factors can in fact directly 

help prevent Alzheimer’s or cognitive decline. 
9

Do Exercise and Physical Activity Protect the Brain?

Exercise and other types of physical activity have many benefits. 

Studies show that they are good for our hearts, waistlines, and 

ability to carry out everyday activities. Epidemiological studies 

and some intervention studies suggest that physical exercise 

may also play a role in reducing risk for Alzheimer’s disease and 

age-related cognitive decline.

Animal studies point to why this might be so. Exercise 

increases both the number of small blood vessels that supply 

blood to the brain and the number of connections between 

nerve cells in older rats and mice. In addition, researchers 

have found that exercise raises the level of a nerve growth 

factor (a protein key to brain health) in an area of the brain 

that is important to memory and learning. 

Researchers have also shown that exercise can stimulate the 

human brain’s ability to maintain old network connections 

and make new ones that are vital to healthy cognition. In a 

year-long study, 65 older people exercised daily, doing either 

an aerobic exercise program of walking for 40 minutes or a 

nonaerobic program of stretching and 

toning exercises. At the end of the trial, 

the walking group showed improved 

connectivity in the part of the brain 

engaged in daydreaming, envisioning 

the future, and recalling the past. The 

walking group also improved on executive function, the ability to plan and 

organize tasks such as cooking a meal.

Several other clinical trials are exploring further the effect 

of physical activity on the risk of Alzheimer’s and cognitive 

decline. Other NIA-supported research is examining whether 

exercise can delay the development of Alzheimer’s disease 
10

in people with MCI. Findings from these and other clinical 

trials will show more definitively whether exercise helps 

protect our brains from cognitive impairment.

Does Diet Matter? 

A number of studies suggest that eating certain foods may help 

keep the brain healthy—and that others can be detrimental to 

cognitive health. A diet that includes 

lots of fruits, vegetables, and whole 

grains and is low in fat and added sugar

can reduce the risk of many chronic 

diseases, including heart disease and 

type 2 diabetes. Researchers are looking 

at whether a healthy diet also can help 

preserve cognitive function or reduce 

the risk of Alzheimer’s. 

Studies have found, for example, that a diet rich in vegetables, 

especially green leafy vegetables and cruciferous vegetables like 

broccoli, is associated with a reduced rate of cognitive decline. 

One epidemiological study reported that people who ate a 

“Mediterranean diet” had a 28 percent lower risk of developing

MCI and a 48 percent lower risk of progressing from MCI to

Alzheimer’s disease. A Mediterranean diet includes vegetables,

legumes, fruits, cereals, fish, olive oil, mild to moderate

amounts of alcohol, and low amounts of saturated fats, dairy 

products, meat, and poultry. 

While some foods may stave off cognitive decline, other foods, 

such as saturated fats and refined carbohydrates (white sugar, 

for example), may pose a problem. In one study, scientists fed 

rats a “Western” diet high in fats and simple carbohydrates for 

90 days. The results: rats fed this high-energy diet performed 

significantly worse on certain memory tests than rats fed a diet 

containing one-third the fat. Notably, the rats scored poorly 
11

on tests that involve the hippocampus, a part of the brain that 

plays a major role in learning and memory.

Some scientists have focused on DHA (docosahexaenoic acid), 

an omega-3 fatty acid found in salmon and certain other fish. 

Studies in mice specially bred to have features of Alzheimer’s 

disease found that DHA reduces beta-amyloid plaques, 

abnormal protein deposits in the brain that are a hallmark 

of Alzheimer’s. Although a clinical trial of DHA showed no 

impact on people with mild to moderate Alzheimer’s disease, it 

is possible that DHA supplements could be effective if started 

before cognitive symptoms appear. 

These findings are of great interest and suggest possible areas 

for future study. The NIA supports clinical trials to examine 

the relationship between several dietary components and 

Alzheimer’s disease and cognitive decline. 

What Is the Effect of Other Chronic Diseases?

Age-related diseases and conditions—such as vascular disease, 

high blood pressure, heart disease, and type 2 diabetes—may 

increase the risk of Alzheimer’s and cognitive decline. Many 

studies are looking at whether this risk can be reduced by 

preventing or controlling these diseases and conditions 

through medication or changes in diet and exercise. 

Much of the evidence about possible ties 

between vascular diseases and Alzheimer’s 

risk comes from observational studies. 

For example, high cholesterol levels and 

obesity during midlife—known risk 

factors for heart disease—have also been 

linked to increased risk of Alzheimer’s 

disease. High blood pressure may be 

another risk factor.
12

What About Vitamins and Dietary Supplements?

Can any vitamins or dietary supplements protect the 

brain from Alzheimer’s disease and cognitive decline? 

One area of research focuses on antioxidants, 

natural substances that appear to fight damage 

caused by molecules called free radicals. Other 

studies are looking at a compound called resveratrol.

As a person ages, free radicals can build up in nerve 

cells, causing damage that might contribute to 

Alzheimer’s. Some epidemiological and laboratory 

studies suggest that antioxidants from food or dietary 

supplements help prevent this oxidative damage—

and lower the risk of 

Alzheimer’s disease—

but other studies have 

shown no effect. Vitamin 

E, vitamin C, B vitamins, 

ginkgo biloba, and 

coenzyme Q have all been 

tested in clinical trials, but 

none has proven effective 

in preventing or slowing 

down Alzheimer’s disease.

Resveratrol, a compound found in red grapes as

well as supplements, appears to have properties

that may help protect the brain. Observational 

studies have shown that moderate consumption 

of red wine is associated with a lower incidence of 

Alzheimer’s disease, and animal studies have shown 

that resveratrol can reduce beta-amyloid deposits 

in the brain. Resveratrol also appears to affect the 

biological processes of aging-related diseases, 

including Alzheimer’s. An NIA-supported clinical 

trial will test the effects of resveratrol in people with 

Alzheimer’s disease.
13

One NIH clinical trial is looking at 

how lowering blood pressure to or 

below current recommended levels 

may affect cognitive decline and the 

development of MCI and Alzheimer’s 

disease. Participants are older adults with 

high systolic blood pressure who have a 

history of heart disease or stroke, or are 

at risk for those conditions. 

Diabetes is another disease that has been linked to Alzheimer’s. 

Previous research suggests that abnormal insulin production 

(insulin is the hormone involved in diabetes) contributes 

to Alzheimer’s-related brain changes. Can restoring normal 

insulin function in the brain provide cognitive benefits? 

The results so far are mixed. One large NIH-funded clinical 

trial compared intensive glucose-lowering treatment with 

standard treatment in nearly 3,000 older adults with diabetes. 

After 40 months, the two groups showed no significant 

difference in cognitive function. But pilot testing of an 

insulin nasal spray has shown promising results. A clinical 

trial is testing this potential treatment in older adults with 

MCI or mild to moderate Alzheimer’s disease to see if it can 

improve memory and daily functioning.

Additional studies and clinical trials are looking at cardiovascular 

and diabetes medications to see if they might prevent Alzheimer’s 

disease. These therapies include aspirin, medications used to 

treat high blood pressure and other heart conditions, and the 

diabetes drugs metformin and pioglitazone. 
14

Is Keeping Your Brain Active Important?

Staying cognitively active throughout life—via social engagement or intellectual stimulation—is associated with a lower 

risk of Alzheimer’s disease. Several 

observational studies link continued 

cognitive health with social engagement 

through work, volunteering, or living 

with someone. Mentally stimulating 

activities such as reading books and 

magazines, going to lectures, and playing 

games are also linked to keeping the 

mind sharp.

In a large study of healthy older people, researchers found 

a relationship between more frequent social activity and 

better cognitive function. It is not clear whether improved 

cognition resulted from the social interaction itself or from 

related factors, such as increased intellectual stimulation, that 

generally accompany social interaction. Other studies are 

exploring these relationships.

Intellectually stimulating activities may also reduce the risk 

of Alzheimer’s, studies show. One large observational study 

looked at the impact of ordinary activities like listening to the 

radio, reading newspapers, playing puzzle games, and visiting 

museums. Investigators asked more than 

700 older nuns, priests, and religious 

brothers to describe the amount of time 

they spent doing these activities. After 

4 years, the risk of developing 

Alzheimer’s disease was 47 percent 

lower, on average, for those who did the 

activities most often than for those who 

did them least frequently. 
15

A more recent study showed that people with less education 

who engaged in activities like reading, doing crossword puzzles, 

and writing letters performed as well on memory tests as their 

better-educated peers. Having fewer years of education has 

been associated with a higher risk of dementia. More research 

is needed to see if everyday cognitive activities can reduce the 

risk of cognitive decline in people with less education.

Formal cognitive training also seems to have cognitive benefits. In the Advanced Cognitive Training for Independent 

and Vital Elderly (ACTIVE) trial, for example, healthy adults 

65 and older participated in 10 sessions of memory training, 

reasoning training, or processing-speed training. The sessions 

improved participants’ mental skills in the area in which they 

How Might an Active Brain Prevent Alzheimer’s?

The reasons for the apparent link between social 

engagement or intellectual stimulation and Alzheimer’s 

risk aren’t entirely clear, but scientists offer these 

possibilities:

•	 Such activities may protect the brain by establishing

“cognitive reserve,” the brain’s ability to operate 

effectively even when it is damaged or some brain 

function is disrupted. 

•	 These activities may help the brain become more 

adaptable in some mental functions, so it can 

compensate for declines in other functions. 

•	 People who engage in these activities may have

other lifestyle factors that protect them against 

Alzheimer’s disease. 

•	 Less engagement with other people or in intellectually stimulating activities could be the result of very 

early effects of Alzheimer’s rather than its cause.
16

were trained. These improvements persisted 10 years after the 

training was complete. 

Another approach is testing the impact of formal cognitive 

training, with and without aerobic exercise. For example, an 

NIA-funded clinical trial is investigating the effectiveness of 

cognitive training, alone and combined with aerobic exercise, 

in people with MCI to see if it can prevent or delay Alzheimer’s 

disease. Other trials are underway in healthy older adults to 

see if exercise and/or cognitive training (for example, a 

demanding video game) can delay or prevent age-related 

cognitive decline.

Other types of formal cognitive 

training are being studied in healthy 

older adults to explore their impact 

on age-related cognitive decline. 

Types of training being tested in 

NIA-funded trials include learning 

digital photography or quilting and 

volunteering at local schools.
17

Other Clues to Alzheimer’s Prevention

The quest for ways to prevent Alzheimer’s disease is part of a

broad research program that is exploring a number of 

possibilities. For example, scientists are looking at caregiver 

stress and physical frailty as possible risk factors for Alzheimer’s 

disease and MCI. Other areas of interest include hormones 

and immunization. 

Hormones

Scientists are studying hormones—especially those taken by 

older women as menopausal hormone therapy—for their 

potential ability to prevent or delay Alzheimer’s disease and 

age-related cognitive decline. Several clinical trials are testing 

forms of estrogen as well as testosterone and other hormones 

in both healthy older adults and those with MCI.

Hormones such as estrogen and progesterone have important 

effects on the brain, many of which could relate to cognitive 

aging and Alzheimer’s disease. Over the years, research has led 

to conflicting reports as to whether menopausal hormone therapy 

can prevent cognitive decline in postmenopausal women.

Some animal and observational studies comparing women 

who did and did not take estrogen have shown that the 

hormone may benefit cognition. However, clinical trials of 

estrogen and progestin in older women have generally failed 

to show similar beneficial effects. In fact, one large study 

showed that prolonged treatment with these hormones 

actually increased the risk of dementia in women 65 and older.
18

Researchers now wonder if it may be 

better for women to start taking 

hormones closer to menopause. NIAfunded clinical trials are studying the 

timing of menopausal hormone therapy 

on cognition and other health factors. 

Other hormones being studied in clinical 

trials for their effects on Alzheimer’s and 

cognitive decline include testosterone, 

which is being tested in older men with MCI and low levels of 

the hormone; growth hormone releasing hormone (GHRH), 

in healthy older adults and those with early MCI; and DHEA, 

in healthy postmenopausal women.

Immunization 

The idea of a vaccine to prevent Alzheimer’s disease is under 

scrutiny as well. Early vaccine studies in mice were so successful 

in reducing deposits of Alzheimer’s-related proteins in the brain 

and improving performance on memory tests that investigators 

conducted preliminary clinical trials in humans with Alzheimer’s 

disease. These studies had to be stopped, however, because lifethreatening brain inflammation occurred in some participants. 

Scientists continue to refine this approach, hoping to maintain 

the vaccine’s possible benefits while reducing side effects. Several 

pharmaceutical companies are testing potential vaccines for 

safety and effectiveness in clinical trials. 

The NIA is also supporting a clinical trial testing whether 

intravenous immunoglobulin (IVIg), a blood product containing naturally occurring antibodies that is used to treat 

immune-system disorders, may improve cognition by clearing 

Alzheimer’s plaques from the brain. 
19

The Path to Developing New Treatments

Clinical trials will ultimately tell us what prevents or delays 

Alzheimer’s and cognitive decline. But other areas of research 

are critical for developing successful prevention strategies. 

Basic studies of the cellular and molecular roots of Alzheimer’s 

are revealing a wide range of processes that interfere with, 

or enhance, the function and survival of nerve cells in the 

brain. These basic research discoveries point to new targets for 

Alzheimer’s treatment. 

Translational studies build on the 

findings from basic research to 

develop new drugs and interventions. 

More than 60 projects in the NIA’s 

translational research portfolio have 

supported early drug discovery and 

early clinical development of new 

treatment compounds for Alzheimer’s. 

The goal is to expand possible avenues 

for Alzheimer’s prevention and treatment and, eventually, to 

increase the number of therapies that can be tested in humans. 
20

Finding Out Who Is At Risk

Several clinical trials of medications and other therapies 

have failed to improve memory and other thinking 

skills in people diagnosed with Alzheimer’s disease. 

Scientists want to try some of these interventions 

earlier in the disease process, in cognitively normal 

people at high risk of developing Alzheimer’s, to see if 

they can prevent or delay the onset of the disease.

To conduct such studies, researchers must first figure 

out which people without Alzheimer’s symptoms are in 

fact at risk of developing the disease. Because the brain 

damage caused by Alzheimer’s begins years before 

memory loss and other symptoms may appear, scientists 

are developing methods to detect biological changes 

related to Alzheimer’s disease at its earliest stages.

Researchers are finding that changes in certain proteins 

in blood and cerebrospinal fluid and results of brain 

scans can indicate early Alzheimer’s-like changes in the 

brain. Understanding more about these “biomarkers” 

may reveal how Alzheimer’s disease begins and develops. 

Biomarkers also may help scientists track whether 

certain medications have their intended effects early in 

the course of the disease.

An NIA-led public-private partnership—the Alzheimer’s 

Disease Neuroimaging Initiative (ADNI)—is examining 

the relationship between these biomarkers and cognitive 

changes in older participants who are cognitively 

normal or have MCI or Alzheimer’s. Scientists hope 

the results will help identify ways to determine the 

risk of Alzheimer’s disease more accurately in people 

without dementia symptoms. 
21

So, What Can You Do?

You can do many things that may keep your brain healthy 

and your body fit—and help scientists find ways to prevent 

Alzheimer’s.

Stay Healthy

Many actions lower the risk of chronic diseases and boost 

overall health and well-being. As we learn more about the 

role they may play in Alzheimer’s disease risk, health experts 

encourage all adults to:

● exercise regularly 

● eat a healthy diet rich in fruits and vegetables 

● engage in social and intellectually stimulating activities 

● control type 2 diabetes 

● lower high blood pressure levels 

● lower high blood cholesterol levels 

● maintain a healthy weight

● stop smoking

● get treatment for depression

Scientists do not yet know if these 

healthy habits can directly prevent or 

delay Alzheimer’s disease or age-related 

cognitive decline. As research continues, 

it’s important to note the many benefits 

these habits have for overall health and 

well-being. 
22

Participate in Research

Whether or not you have signs of Alzheimer’s, you can 

take one more important action—volunteer to participate 

in clinical trials and studies. Volunteers want to make a 

valuable contribution that will help scientists, people with 

Alzheimer’s, and their families. People who participate in 

this kind of research also have regular contact with medical 

experts who have lots of experience and 

a broad perspective on the disease. 

To learn more about clinical trials or 

to find study sites near you, contact 

the NIA’s Alzheimer’s Disease Education and Referral (ADEAR) Center at 

1-800-438-4380 or visit www.nia.nih.

gov/alzheimers/clinical-trials.

A Word of Caution

Because Alzheimer’s disease is so devastating, some 

people are tempted by untried or unproven “cures.” 

Check with your doctor before trying pills or any 

other treatment or supplement that promises to 

prevent Alzheimer’s. These “treatments” might be 

unsafe, a waste of money, or both. They might even 

interfere with other medical treatments that have 

been prescribed.
23

For More Information

Alzheimer’s Disease Education and Referral (ADEAR) Center

P.O. Box 8250

Silver Spring, MD 20907-8250

1-800-438-4380 (toll-free)

www.nia.nih.gov/alzheimers 

The NIA’s ADEAR Center offers information and publications 

for families, caregivers, and professionals on diagnosis, 

treatment, patient care, caregiver needs, long-term care, 

education, training, and research related to Alzheimer’s disease. 

Staff members answer telephone, email, and written requests 

and make referrals to local and national resources. Visit the 

ADEAR website to learn more about Alzheimer’s and other 

dementias, find clinical trials, and sign up for email updates. 

Alzheimer’s Association

225 North Michigan Avenue, Floor 17

Chicago, IL 60601-7633 

1-800-272-3900 (toll-free)

1-866-403-3073 (TDD/toll-free)

www.alz.org

The Alzheimer’s Association is a national nonprofit 

organization with local chapters that provide education and 

support for people with Alzheimer’s disease, their families, 

and caregivers. The Association also funds research on 

Alzheimer’s.
24

Alzheimer’s Disease Cooperative Study

University of California, San Diego

9500 Gilman Drive M/C 0949

La Jolla, CA 92093-0949

1-858-622-5880

www.adcs.org

The Alzheimer’s Disease Cooperative Study (ADCS) is a 

consortium of NIA-supported medical research centers and 

clinics that develop and conduct Alzheimer’s clinical trials. 

Alzheimer’s Foundation of America

322 8th Avenue, 7th Floor

New York, NY 10001

1-866-232-8484 (toll-free)

www.alzfdn.org 

The Alzheimer’s Foundation of America is a group of 

organizations that help individuals with Alzheimer’s disease 

or other dementias. Services for consumers include a tollfree hotline that offers information and referrals, educational 

materials, conferences for caregivers, and a free quarterly 

magazine for caregivers. 

ClinicalTrials.gov

www.clinicaltrials.gov

ClinicalTrials.gov is a registry of federally and privately 

supported clinical trials. Users can search for clinical trials 

and find information about each trial’s purpose, who may 

participate, locations, and other details.
For more information about 

Alzheimer’s disease, please contact:

Alzheimer’s Disease Education and 

Referral (ADEAR) Center

www.nia.nih.gov/alzheimers 

1-800-438-4380 (toll-free)

adear@nia.nih.gov

National Institute on Aging
National Institute on Aging

National Institutes of Health

NIH...Turning Discovery Into Health®

U.S. Department of Health and Human Services 

Publication No. 12-5503

September 2012