Alzheimer's Disease and Brain Health

The brain is a curious thing. In fact, the brain is so curious that it instinctively drives humans to be curious about it. As a result, much is known about brain science and the field is advancing. Yet, much remains unknown and questions about the impact of diet and lifestyle on the brain continue to be studied. A new book by David Perlmutter, MD, “Grain Brain,” proposes that specific food groups, macronutrients and ingredients in food be avoided or eliminated from the diet completely due to his belief that they are uniquely detrimental to brain health. His perspective, however, is not shared by leading food and nutrition organizations and experts from around the world. They, on the other hand, have thoroughly examined the totality of scientific evidence and encourage a balanced diet and emphasize inclusion of all food groups for optimal health, including the health of our brains.

The nutrition science community offers science-driven dietary guidance to promote overall health, but what do experts in brain science have to say about the brain’s reaction to various diets and lifestyles? To answer these questions and more, we spoke with Heather M. Snyder, Ph.D., Director of Medical & Scientific Relations at the Alzheimer’s Association.

Q: What is Alzheimer’s disease?

A: Alzheimer’s disease is a progressive brain disease and the sixth leading cause of death in America. Symptoms of the disease include memory loss, changes in patterns of behavior, and marked differences in thinking and reasoning skills. The Alzheimer’s Association has developed the 10 Warning Signs of Alzheimer’s which you can find on our website, www.alz.org

Q: What causes Alzheimer’s disease?

A: The specific causes of Alzheimer’s are unknown at this time, but research is ongoing to identify them.

Q: Are there any factors that increase or decrease risk for the disease?

A: Age is the greatest risk factor for Alzheimer’s disease.  Approximately 1 in 9 individuals over the age of 65, and 1 in 3 over the age of 85, will develop Alzheimer’s disease.  Research suggests an increased risk of Alzheimer’s if a person has (1) a parent or sibling with the disease, (2) cardiovascular disease or diabetes; or (3) experienced a head injury or traumatic brain injury.

The strongest evidence today suggests engaging in regular physical activity may reduce an individual’s risk of developing Alzheimer’s disease or a related dementia.  Additional hints in research suggest activities that promote lifelong learning or mental stimulation, and activities that engage an individual socially, may be able to reduce an individual’s risk.  Finally, we also see some evidence linking a heart-healthy diet to potentially reduced risk of Alzheimer’s disease. 

Q: Can Alzheimer’s be prevented?

A: Currently, there is no known prevention for Alzheimer’s disease. In fact, among the top 10 causes of death in the U.S., Alzheimer’s is the only one that cannot be slowed, cured or prevented. However, there are several efforts underway to investigate the best methods of identifying an individual’s risk for Alzheimer’s disease – and clinical trials are starting soon to determine if treating those at high risk for the disease can delay the symptoms or prevent them from ever occurring.

Q: Once Alzheimer’s has been diagnosed, what can be done to slow or reverse the progression?

A: There is no way to stop or slow the progression of Alzheimer’s today.  The U.S. National Plan to Address Alzheimer’s Disease, first released in May 2012, sets forth an aggressive research agenda to prevent and effectively treat Alzheimer’s disease by 2025—a significant increase to our national commitment to ending Alzheimer’s is needed.

Q: Can you clarify the difference between Alzheimer’s and other brain health terms such as dementia and mild cognitive impairment?

A: Dementia is not a specific disease. It is the umbrella term for many brain conditions related to decline in memory, thinking and function.  Alzheimer’s disease is the most common cause of dementia – approximately 60-70% of cases. 

Mild cognitive impairment, or MCI, refers to subtle memory changes in an individual, and may be an early sign that someone will develop Alzheimer’s disease.  However, not everyone with MCI develops Alzheimer’s disease, and some people with MCI regain their functioning. 

Revised diagnostic guidelines for Alzheimer’s – published by the Alzheimer’s Association and the National Institute on Aging – suggest that Alzheimer’s disease is a continuum, with the underlying brain changes of the disease occurring 10 or 20 years before someone experiences declines in memory and thinking. The goal is that, one day, we will be able to identify someone early on who has the underlying biological changes and intervene at that time to stop or slow the disease, hopefully before they ever have dementia symptoms.

Q: Researchers continue to study the role of diet and lifestyle in overall health, but what is known about the connection between diet, lifestyle and brain health?

Revised diagnostic guidelines for Alzheimer’s – published by the Alzheimer’s Association and the National Institute on Aging – suggest that Alzheimer’s disease is a continuum, with the underlying brain changes of the disease occurring 10 or 20 years before someone experiences declines in memory and thinking. The goal is that, one day, we will be able to identify someone early on who has the underlying biological changes and intervene at that time to stop or slow the disease, hopefully before they ever have dementia symptoms.

The strongest evidence today suggests engaging in regular physical activity may reduce an individual’s risk of developing Alzheimer’s disease or a related dementia.  Additional hints in the research suggest the possible benefits of lifelong learning and/or mental stimulation, and activities that engage an individual socially. We also see evidence linking a heart-healthy diet (a balanced diet emphasizing dark leafy green vegetables, nuts, fish, and whole grains -- and low in saturated fat) to potentially reduced risk of Alzheimer’s disease. In other words, when it comes to diet and exercise, what’s good for the heart is good for the brain.

Q: Is there a “best” diet for optimal brain health?

A: There is not enough information available to say there’s a “best” diet for optimal brain health. Hints in the literature suggest that diets such as the Mediterranean diet — one that is rich in fruits and vegetables, nuts, olive oil, fish, grains (often whole grains), and small quantities of meats — may be beneficial, but this is still an ongoing area of investigation. 

When it comes to good brain health, diet is just one component. Other lifestyle behaviors may also be a factor – regular physical activity, for example. Looking at the bigger picture of health is critical for your brain.

Q: Is science close to finding a cure for Alzheimer’s?

A: Our progress toward finding a cure will be directly proportional to our investment in Alzheimer’s disease research. The Alzheimer’s Association convened a group of scientific experts to evaluate the state of the field and determine what is needed to effectively treat or prevent Alzheimer’s disease by 2025. They concluded that research funding of approximately $2 billion a year over 10 years is what is needed.  We are seeing incremental increases in the federal commitment, but we are still a long way from $2 billion annually. 

We stopped polio. We’ve found ways to treat heart disease, and can now prevent, treat, and even cure many kinds of cancer. Federal investment in basic research and treatment trials has led the way for each of those achievements, and it is needed now for Alzheimer’s disease. The Alzheimer’s Association vision is a world without Alzheimer’s disease, and we will continue to advance efforts to achieve this goal. 

Q: If you could give one piece of advice for families with loved ones afflicted by the disease, what would it be?

A: Research shows that families affected by Alzheimer’s cope better with the many changes brought on by the disease when they learn about the disease, caregiving techniques, and what to expect. Many education and support resources are available in the community, including the Alzheimer’s Association and its local chapter offices.  More information is available through our website – www.alz.org – or our 24/7 free national helpline, 800-272-3900.  They can answer questions about Alzheimer’s disease, help with local referrals, or assist in a difficult care situation with a master’s level trained clinician.

During the month of September, World Alzheimer’s Month is recognized around the globe. In November, Americans observe National Alzheimer’s Disease Awareness Month. In October, we honor both of these occurrences by taking the opportunity to learn more about Alzheimer’s and raise awareness about appropriate actions that positively influence the health of our brains. Despite many advancements, a cure for Alzheimer’s has not been found. With the increasing number of Americans entering their golden years, responsible guidance for optimal brain health is of critical importance.