How to Assess Your Risk Factor for Neurodegenerative Diseases + What You Can Do to Prevent Cognitive Decline

By Dr. Will Cole

There is an epidemic in America. Close to 5.2 million people in the United States and 1 in 8 people 65 and over are currently diagnosed with Alzheimer’s disease. As the sixth leading cause of death in America, this debilitating disease destroys quality of life for those diagnosed while they are still alive.

Unfortunately, there is no cure for this condition. Once you are diagnosed, there is a gradual decline in memory until, for many, not much or any memory is left at all. But is it possible to age gracefully without this disease? Or is it just a matter of time before this becomes our fate into our “golden” years?

As a leading functional medicine practitioner who consults people around the world, I’ve seen firsthand that this disease doesn’t have to be a person’s destiny - even if you are genetically predisposed to this condition as some people are.

Genetics: Suggestion or Life Sentence?

Your genetics influence almost every aspect of your health. Everything from your weight, mood, hormones, and immune system can be traced back to your DNA. And for some people, certain genetic mutations can be linked to an increase in Alzheimer’s risk.

The APOE gene controls the transportation of saturated fat in the body to areas where it is needed, and certain variants - APOE 3/4 or APOE 4/4 - control the efficiency of this transportation process. Those with APOE 3/4 have a slower transportation time and have more difficulty metabolizing saturated fat.

But those with the APOE 4/4 version of this gene have the highest risk for Alzheimer’s as this double allele makes it even more difficult for the body to metabolize saturated fats, causing them to build up in the body, whether that is in the heart as plaque or as amyloid plaque in the brain that is linked to Alzheimer’s. In fact, according to the Alzheimer’s Association, autopsy studies have shown that close to 80% of people with Alzheimer’s also had cardiovascular disease. This is especially of note for people with insulin resistance, as this condition makes the APOE44 gene variant even more detrimental.

But there is another side of the coin to this genetic puzzle. In reality, the more we learn about how health problems develop over time, the more we see that genetics are often a poor predictor of the ultimate fate of your health. Research has shown that only 33% of a person’s health is actually determined by genetics whereas the other 77% is determined by controllable factors such as lifestyle choices and diet. Talk about a relief.

Therefore, even those with the APOE gene variant don’t necessarily have to prepare for a life with Alzheimer’s in older age if the proper lifestyle adjustments are made early on. While nothing is guaranteed, we’ve seen over time in research how changing our health habits can make a dramatic impact in our health. Whether that is stopping the expression of that gene altogether, or drastically decreasing its expression, both are a win when compared to the full-blown effects of this disease.

So how do you know your risk? These tests will help you know where you stand so you can make the changes necessary to live your best life well into your future.

Assess Your Risk

1. Hemoglobin A1C and fasting blood sugar

Research actually refers to Alzheimer’s as type 3 diabetes due to the link between this condition and blood sugar imbalance. It has been found that the more degeneration in the hippocampus - the memory center of the brain - the higher blood sugar levels tend to be. In fact, those with type 1 and type 2 diabetes are more likely to be diagnosed with Alzheimer’s. Alzheimer's has even been referred to as Type 3 diabetes in the scientific literature!

Optimal Range: < 5.3%

2. Homocysteine and inflammation tests

High homocysteine levels can act as a sort of a neurotoxin, increasing blood-brain-barrier (BBB) permeability and is associated with neurodegenerative diseases. 

Optimal Range: < 7

 3. Immunological tests

Surprisingly, the immune system plays a significant role in the development of Alzheimer’s. There is a whole area of research known as the “cytokine model of cognitive function” that explains how certain foods and lifestyle factors can trigger inflammation, autoimmune responses, and degeneration in the brain.

3.Genetic testing

To know if you are genetically predisposed to Alzheimer’s, looking at your genetics will verify whether or not you have one of the variants of the APOE gene as well as methylation genes that predispose to higher homocysteine levels such as MTHFR gene variants. I have written extensivelyabout this in the past. 

Prevention tips

1. Limit saturated fats

Now this tip is mainly for those with either one of the APOE gene variants. In general, saturated fats are beneficial for your health. However, as we have seen, this isn’t the case for everyone. A perfect example of how a one-size-fits all approach doesn’t work for people’s health.

Saturated fats include sources like dairy, coconut oil, animal fats like tallow and lard, and fatty cuts of meat. These don’t have to be avoided completely but should be limited. I typically recommend between 40-50 grams of saturated fat per day for those with the APOE 3/4 gene and between 30-40 grams per day for those with the APOE 4/4 gene. Instead, focus on sources of unsaturated fat such as wild-caught fish, soaked nuts and seeds, olives, avocados, extra-virgin olive oil, and avocado oil.

2. Go keto

Healthy fats are essential for optimal brain health, and a ketogenic diet has been proven to be a powerful defense mechanism against brain deterioration. The ketones produced from ketosis have the ability to cross the blood-brain barrier and provide fuel to your brain while also demonstrating powerful anti-inflammatory abilities.

It’s been shown that diets rich in polyunsaturated fats, wild-caught fish specifically, are associated with a 60 percent decrease in Alzheimer’s disease. Contrast this to high-carb diets, which have been shown to increase the risk of Alzheimer’s disease and other neurodegenerative conditions.

My book Ketotarian, is all about how to do a ketogenic diet plant-based with vegan-keto, vegetarian-keto, and pescatarian-keto versions making it the perfect way to get the benefits of a keto diet while also limiting the amount of saturated fats for those with the APOE gene variants. I also talk about a cyclical ketotarian, which I think works very well for many people. 

3. Practice intermittent fasting

Going for periods of time without food has been shown to decrease overall inflammation in the body, including your brain. Studies have shown that intermittent fasting can protect neurons by increasing autophagy (cellular recycling), and BDNF (encouraging new, healthy neurons) in the brain from genetic and lifestyle stress factors to slow brain deterioration.