Eggs & Cholesterol Don’t Increase Dementia Risk, Science Says

Unbeknownst to most, healthy fats in your diet, including long-feared cholesterol, are proving to be key players in brain and psychological health. In previous generations, people believed cholesterol clogged arteries and caused heart problems. However, today we understand that the standard Western diet, which contains a large amount of hydrogenated fats and refined carbohydrates, leads to an upset in the balance of cholesterol in the body and dangerously high levels of inflammation.

As you’ll learn, cholesterol itself from whole foods like eggs or even real butter shouldn’t be feared. Rather, when it comes to fighting symptoms of aging that affect the brain or elsewhere, the focus should be on reducing intake of high cholesterol foods that disturb the natural balance and use of different cholesterols in the body. These include things like sugary treats, fried foods, processed meats or refined oils.

What New Studies Tell Us about Cholesterol & Cognitive Health

A study published in the American Journal of Clinical Nutrition is shedding light on some long-held beliefs about fat intake and brain health. Researchers from the Institute of Public Health and Clinical Nutrition at University of Eastern Finland found that neither cholesterol nor egg intake seemed to increase the risk of dementia or Alzheimer’s disease. Surprising to some of the researchers, there was actually a link between higher egg intake and better performance on neuropsychological tests of the frontal lobe and executive functioning.

The study investigated the associations of cholesterol and egg intake with dementia, Alzheimer’s, and cognitive performance. It included 2,497 middle-aged and older men (between 41 and 60 years old) from Eastern Finland. Some of the men were tested and shown to have a apolipoprotein E (Apo-E) phenotype, which is believed by some experts to be tied to a heightened risk for cognitive decline. According to Alzheimer’s News Today, the prevalence of APOE4 in Finland is particularly high, with around a full-third of the population carrying it. This is alarming considering the gene was previously thought to be a major risk factor in development of dementia. 

The long-term study followed the participants for 22 years, during which their food intake was recorded. After crunching the numbers from the the 22 year follow-up period, 337 men were diagnosed with dementia and 266 men were diagnosed with Alzheimer’s. The Apo-E4 phenotype did not modify the associations of cholesterol or egg intake; in other words it did not trigger higher rates of disease in those who were more susceptible from the start. Overall the conclusion of the study, according to researchers?

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“Neither cholesterol nor egg intake is associated with an increased risk of incident dementia or AD in Eastern Finnish men. Instead, moderate egg intake may have a beneficial association with certain areas of cognitive performance.” (1)

To further support this point, consider that earlier studies have also shown similar evidence for protective mechanisms of other healthy dietary fats. For example in 2013 the Journal of Neurology, Neurosurgery and Psychiatry published a study showing that elderly people who added more healthy fats to their diets— in the form of foods like olive oil or mixed nuts— maintained their cognitive function much better over a six-year period than those who ate a low-fat diet. According to Science Daily, the so-called “Mediterranean diet”, with a relatively high intake of fats like extra virgin olive oil, seems to improve the brain-power of older people better than advising them to follow a low-fat diet. (2)

Benefits of Dietary Cholesterol

Most adults assume that cholesterol is a leading cause of many diseases, especially coronary artery disease, however as you can see recent studies are debunking this myth. Coronary artery disease, a leading cause of heart attacks, seems to have more to do with inflammation than with high cholesterol. In fact cholesterol even has benefits, some of which include:

• Acting as a critical brain nutrient essential to the function of neurons. Cholesterol is used as a source of fuel or energy, since neurons cannot themselves generate significant amounts.
• Playing a role in building cellular membranes and the communication network of nerves.
• Serving as an antioxidant and a precursor to important brain-supporting molecules like vitamin D or steroid-related hormones. These include sex hormones such as testosterone and estrogen.
• Helping to deliver nutrients to the brain from the bloodstream via a the carrier protein called LDL (or low-density lipoprotein).

Cholesterol can become imbalanced, manifested in elevated LDL (bad cholesterol) and a low HDL (good cholesterol), when someone lives an unhealthy lifestyle. And this can in fact increase the risk for heart attack or stroke. Causes of a cholesterol imbalance include a poor diet, inactivity, diabetes, stress, and hypothyroidism.

The Eggs-Cholesterol-Dementia Myth

So if cholesterol isn’t to blame for conditions associated with cognitive decline, based on the above, then what is?

A large body of research now shows that inflammation is involved in far more disease processes than we previously had imagined, including cognitive disorders like Alzheimer’s disease or Parkinson’s. (3)

diets high in sugar and low in fiber fuel unwanted bacteria and increase the chances of intestinal permeability. This can lead to cellular changes (such as mitochondrial damage) and compromising of the immune-system compromise. Eventually widespread inflammation may reach the brain. While inflammation has its upsides, and is part of the crux of the body’s natural healing response following injury or infection, when inflammation persists it winds up causing damage to systemic pathways. 

A long-term rise in inflammation is tied to a range of health conditions such as obesity, diabetes, cancer, depression, coronary artery disease and many more. In the case of memory loss, such as with Alzheimer’s, inflammation is exactly what is happening in the brain of a patient who experiences a decline in normal neural functions.

Many biochemicals are related to inflammation, both in the brain and elsewhere in the body. These biochemicals include the types called cytokines, small proteins released by cells that affect the behavior of other cells. Examples of cytokines tied to cognitive impairment include C-reactive protein, interleukin six (IL-6), and tumor necrosis factor alpha (TNF-α).

What about genetics— don’t they have a say in determining if someone loses their memory? While certain genetic factors are tied to a higher risk for diseases like Alzheimer’s or Parkinson’s, they are far from the whole story. We’ve learned that even people with a family history of these disorders can do a lot to influence the expression of their genes, helping to turn off or suppress “bad” genes and potentially activate those that are protective.

What Are Other Ways to Prevent Memory Disorders?

• Eat An Inflammatory Diet— As described above, persistent inflammation is highly tied to cognitive decline. An anti-inflammatory diet helps to improve gut health, feed the brain and cells with energy, and to balance production of mood-boosting neurotransmitters. Aim to eat mostly or all unprocessed foods— especially fresh veggies, healthy fats like coconut or olive oil, probiotic foods, nuts, seeds and plant foods high in antioxidants and fiber.

• Improve Gut Health— Experts are also now uncovering how inflammation stemming from poor gut health, or alterations in the gut microbiota (sometimes called leaky gut syndrome), can pave the way for the development of disease. For example GABA, one important chemical manufactured by the gut bacteria, is an amino acid that serves as a neurotransmitter in the central nervous system and regulator of memory and moods. GABA and related chemicals help to regulate nerve activity and brain waves. A healthy diet and following the steps below will set the scene for better balance of gut microbiota.

• Maintain Normal Blood Sugar (Glucose) Levels—Maintaining healthful blood sugar levels (in other words decreasing risk for type 2 diabetes which partly develops from prolonged elevated blood sugar) prevents a stir-up of inflammation in the bloodstream. Those with type 2 diabetes are under a lot of metabolic stress and have a harder time bringing glucose from the bloodstream into their cells, which affects the central nervous system, nerves and brain. High intakes of processed sugar can be toxic and contribute to glycation, a biological process that causes sugar to bind to proteins and certain fats, resulting in deformed molecules that can be hard to regulate. (4) There’s some evidence that Traditional Chinese herbs along with other anti-inflammatory spices, fresh veggies and compounds found in tea, coffee, wine, and dark cocoa/chocolate have anti-diabetic qualities, and therefore many benefits for cognitive and gut health.

• Exercise Regularly— Exercise is practically natural medicine for your brain and nervous system. It reduces inflammation, can protect you from depression or anxiety, and even seems to lower risk for diabetes, gut alterations and low immune function. According to the Mayo Clinic, based on many studies, “A rapidly growing literature strongly suggests that exercise, specifically aerobic exercise, may attenuate cognitive impairment and reduce dementia risk.” (5) You’ll get the most brain-protective benefits from exercise by aiming for at least 150 minutes weekly.

• Manage Stress—  Too much stress can take a major toll on your immune and central nervous systems. High levels of uncontrolled, chronic stress are tied to increased inflammation and of course various mood-related problems due to neurotransmitter changes. (6) In areas of the world where people live the longest (and often times happiest) lives, stress is controlled through things like social support, spirituality, meditation, exercise and having a strong life purpose.

Final Thoughts

• Although previous studies have suggested that a high-fat diet might be a risk factor for certain cognitive problems that occur in older age, new studies are finding the opposite to be true. A recent study found that neither cholesterol nor egg intake seems to be associated with a higher risk of dementia or Alzheimer’s disease (AD) in older men, even when the men have a gene that was thought to increase risk.
• The study also found that higher egg intake was actually associated with better performance on neuropsychological tests and executive functioning.
• Considering cholesterol is known to have certain benefits— including serving as an antioxidant and providing a fuel source for the brain and neurons— it’s not totally surprising that other studies show diets high in healthy fats can be protective over cognition and memory.
• Rather than reducing cholesterol or fat intake, you can lower your odds for suffering from memory loss in older age by eating an inflammatory diet, improving gut health, preventing diabetes and exercising.

Read Next: The Heart-Healthy, Disease-Preventing Health Benefits of Eggs