The development of Alzheimer’s disease

Alzheimer’s disease (AD) is the most common form of dementia, causing progressive mental decline over many years starting around the age of 65; though rare early-onset dementia can start around age 35. This mental decline is caused by damage to the brain concentrated in the hippocampus, the portion of our brain responsible for forming memories and regulating mood and emotions.

The damage to the hippocampus is characterized by the accumulation of two types of protein: tau tangles, or tangles of nerve fibers, and amyloid-beta plaques. There is also a significant loss of connections between neurons in those who develop AD, affecting cognition as well as muscle and nerve coordination in the body.

Early warning signs for AD will vary from person to person but could include:

• Memory loss
• Decline in cognition, such as difficulty coming up with the right words
• Impaired judgment or reasoning
• Confusion or forgetfulness
• Taking longer than normal to complete tasks
• Mood and personality changes

There is indeed a genetic component to whether someone is at risk for developing Alzheimer’s disease, such as the presence of certain mutations of apolipoprotein E (APOE). The presence of this gene mutation does not dictate whether someone will go on to develop AD – it simply means they are at an increased risk. There are other genes, such as those that regulate inflammation and cleanup plaque in the brain, that also contribute to the potential development of this disease.

Genetics may “load the gun,” but environment “pulls the trigger,” which means that the expression of certain genes will depend a lot on your diet, lifestyle, and environment. Living a preventive health lifestyle is key, especially when it comes to taking care of your long-term health and protecting your body from such progressive diseases.

We’ll explore the role that diet, lifestyle, and our environment – including “primary food,” the things in our life that aren’t food but still nourish us – play in reducing the risk of developing Alzheimer’s disease. If you’re young, you may not think you have to worry about Alzheimer’s, but it’s never too early to start thinking about how to protect your health long-term.

The role of diet

The foods we eat (and don’t eat) is one piece of living a preventive health lifestyle. A general disease-prevention diet is high in:

• Colorful fruits and vegetables
• Quality protein, whether animal- or plant-based
• Healthy fats, such as omega-3s found in fatty fish, chia seeds, and walnuts
• Complex carbohydrates found in non-starchy vegetables, such as sweet potatoes, as well as in grains, such as quinoa
• Adequate fiber, including prebiotics that feed gut bacteria
• Anti-inflammatory foods, many of which are included above, as well as herbs, such as turmeric

You’ll notice that this way of eating is free from processed foods and sugar. Dr. Mark Hyman, functional medicine physician and IIN visiting teacher, refers to Alzheimer’s disease as type 3 diabetes due to sugar’s toxic effects on the brain. He says that an overconsumption of sugar and an underconsumption of fat (did you know the brain is 60% fat?) causes inflammation to run rampant in the body and the brain. This inflammation doesn’t happen overnight – Dr. Hyman explains that it takes years to develop, which is why catching potential warning signs for Alzheimer’s disease is not only possible but very important.

When it comes to a specific diet to prevent the onset of AD, doctors often turn to the MIND diet, which stands for Mediterranean-DASH Intervention for Neurodegenerative Delay. The Mediterranean diet is rich in healthy fats, such as olive oil and nuts, and focuses on consumption of vegetables, fruits, beans, and fish or poultry as main sources of protein. The DASH diet takes a similar approach, developed to decrease blood pressure, a risk factor for developing AD. Observational studies have shown that adhering to the MIND diet is associated with a slower rate of cognitive decline and a reduced risk of AD.

In general, by limiting your consumption of processed foods high in sugar and foods high in saturated fat and focusing on a balanced yet varied whole foods diet, you’ll set your body and your brain up for success! One last tip – focusing on your gut health can also help reduce your risk for developing AD. Emerging research demonstrates that the gut-brain axis, or the communication between the gut microbiome and the brain, can be affected by gut dysbiosis and dysfunction, leading to inflammation that spreads to the brain.

The role of preventive lifestyle practices

When it comes to popular lifestyle practices that can prevent disease, exercise is at the top of the list. Engaging in regular exercise is one of the best ways to keep your body and your brain healthy:

• Exercise improves your blood sugar – In the short-term, exercise improves insulin sensitivity, which means your muscles are better able to utilize available glucose. In the long-term, this increased insulin sensitivity leads to a lower A1C, an indicator of average blood sugar levels over time that can be used to diagnose pre-diabetes and diabetes. Research has shown that the risk of developing Alzheimer’s disease is 65% higher in those who have diabetes than those without diabetes.
• Exercise improves blood pressure and vascular health – Regular physical activity helps promote better blood pressure because blood vessels are better able to dilate, improving structure and function of our vascular system. Dysfunction of the vascular system can prevent plaque buildup in the brain from getting cleared, and research has demonstrated that an unhealthy vascular system can contribute to neuroinflammation.
• Exercise can decrease inflammation – In a study published in Brain, Behavior, and Immunity, researchers found that just 20 minutes of moderate exercise decreased the levels of pro-inflammatory cytokines in participants’ blood. Reducing overall inflammation in the body is important in the prevention of not just AD but many lifestyle-related chronic conditions.

In addition to keeping your body active, it may also be helpful to keep your mind active as part of a preventive lifestyle. Your brain is a muscle, and just as your arms, legs, back, and core need strengthening, so does your brain! While research is inconclusive around whether doing mental exercises to keep your mind sharp can prevent the development of dementia and Alzheimer’s disease, there is an argument to be made for regularly challenging your brain to prevent boredom, improve emotional well-being, and improve quality of life.

Other positive lifestyle behaviors that can reduce your risk of disease include not smoking, drinking alcohol moderately, and taking steps to improve your physical environment, such as eliminating toxins from the home. 

The role of primary food

Fulfilling areas of our lives that impact our well-being, such as fostering positive relationships, engaging in creative activities, learning new things, experiencing joy, and having a career that aligns with our passions, can sometimes feel a bit more complicated than nourishing ourselves through a nutritious diet, but they are incredibly important.

These areas of our health, what we at IIN refer to as “primary food” (making the actual food on our plate “secondary”), have been shown to affect the health of our brain:

Relationships – Studies support the association between having a strong social network and support with positive cognitive function, including working memory.

Creativity – Learning something new, such as picking up a musical instrument or a new language, may help slow cognitive decline. This could also include playing games, solving puzzles, or taking a class. For those who may go on to develop Alzheimer’s disease, brain training could mean less time in a state of cognitive decline.

Education – In an observational cohort study, researchers looked at survey data of more than 21,000 U.S. adults and found there was an association between attainment of higher education and decreased prevalence of dementia, meaning those who stayed in school longer were less likely to develop dementia.

Joy – Cultivating a sense of joy in our everyday lives is crucial for our psychological well-being, which is positively associated with better cognitive function. Joy provides an opportunity for an individual to learn new skills, forge new relationships, and improve resilience, all things that add up to a healthy mental and emotional state.

It’s not too late to start implementing healthier habits.

Though Alzheimer’s disease is not necessarily a fun topic to talk about, it’s important to be reminded of how our short-term choices can impact our long-term health. It can seem daunting to make all these changes at once, especially when many changes won’t produce “quick results.” Shifting toward a preventive health lifestyle is all about mind-set, which can take time to cultivate and settle in. The key is being kind and patient with yourself. Better yet, speak to an accountability buddy or Health Coach, who can help you reach your health goals and create sustainable habits. It’s never too late to get started – your body and mind will thank you!