“You’re nothing but a pack of neurons.”

So said Dr. Francis Crick, molecular biologist and neuroscientist who was awarded a 1962 Nobel Prize for having identified the structure of DNA.  Neurons are fundamental in understanding Alzheimer’s Disease (“AD”).  And, while neuron health can be impacted by genetics, there are actions that we can take to keep our neurons healthy, and possibly reduce the risk of AD. 

Neurons are nerve cells in the brain. They are messengers, transmitting information between different areas of the brain and between the brain and the rest of the nervous system, muscles, and other organs.  They use electrical impulses to send chemical signals across tiny gaps between neurons, making our thoughts, memories, feelings, and movements possible.  Our brains have about 100 billion neurons, and a neuron makes 10,000 of these connections with other neurons.  And, while our neurons are constantly “firing,” our brains contain “supporting cells”, called astrocytes and microglia, which are removing debris to keep neurons healthy.

For people who suffer from AD, the normal function of neurons is disrupted by two proteins called beta-amyloid and tau.  These proteins inhibit neurons’ ability to communicate.  Beta-amyloid clumps into plaques which slowly builds up between neurons.  Tau accumulates, abnormally forming tangles inside neurons.  As amyloid increases, tau spreads throughout the brain.  In certain cases, microglial cells fail to clear away brain debris, affecting normal neuron function.  As neurons die, the brain shrinks.  This process starts in the hippocampus, which is the part of the brain important for memory and learning, resulting in the loss of the ability think, remember and function independently. 

Research shows that that toxic changes in the brain may begin a decade or more before cognitive problems appear.  Root causes may be genetic, environmental, or related to lifestyle.  For most people, AD arises from changes to the brain during aging.

While there is currently no cure for AD, there are therapies in development.  Some focus at the molecular level, aiming to reduce or clear the increase of tau and amyloid proteins.  Advances in brain imagery technology are helping to understand how plaques and tangles develop and spread in living people. 

Recent research about the impacts of lifestyle, diet, and social engagement on brain health have emerged, indicating that perhaps some of the root causes of AD can be controlled.  Two studies suggest that there are twelve “modifiable risk factors” that if eliminated could reduce the number of people living with dementia by up to 40%.  The report identified that the three risk factors with the largest potential impact are hearing loss, low education in early life, and smoking.  The full list of factors is:

1. Less education
2. Hearing impairment
3. Smoking
4. Hypertension
5. Obesity
6. Depression
7. Physical inactivity
8. Diabetes
9. Low social contact
10. Excessive alcohol consumption
11. Traumatic brain injury
12. Air pollution

Currently, there is a two-year clinical trial sponsored by the Alzheimer’s Association, called the U.S. POINTER study, to evaluate whether lifestyle interventions impact the risk of cognitive decline. These interventions include physical activity, cognitive and social stimulation, and healthy diet and include these “ten ways to love your brain” to reduce this risk.

• Exercise. Regular cardiovascular exercise to increase blood flow to the brain and body. Several studies have found an association between physical activity and reduced risk of cognitive decline.
• Formal Education. Learning via local college, community center, or online, at any stage of life will help reduce your risk of cognitive decline and dementia.
• No Smoking.
• Take Care or Your Heart. Taking steps to reduce obesity, high blood pressure and diabetes can help your cognitive health.
• Stay Safe! Reduce risk of brain injury by wearing a seat belt or using a helmet when participating in sporting activities. 
• Eat Healthy. A balanced diet that is lower in fat and higher in vegetables and fruit to help reduce the risk of cognitive decline.
• Sleep Well. Not getting enough sleep may result in problems with memory and thinking.
• Get Help. Reduce the risk of depression, anxiety, or other mental health concerns by seeking treatment.
• Staying socially engaged. Pursue meaningful social activities and be part of your local community, or just share activities with friends and family.
• Challenge Your Mind. Benefit your mind with activities or games that make you think strategically.

Dr Crick declared that we are “nothing but a pack of neurons” more than 25 years ago.  Considering recent studies about keeping neurons healthy to avoid Alzheimer’s Disease, he was ahead of his time.  Is it coincidence that his quote is similar to Alice’s retort, “You’re nothing but a pack of cards,” to the King and Queen of Hearts in Lewis Carroll’s Alice in Wonderland—a story about growing up?