Alzheimer’s Prevention – Nutrition

This week’s topic in our ongoing  exploration of Alzheimer’s prevention is NUTRITION

Research into Alzheimer’s prevention has shown a significant impact of nutrition on the preservation of mental function as we age.  Studies have shown that lifestyle changes, specifically dietary changes, have a significant effect on preventing Alzheimer’s disease and preserving cognitive function as we age.

We used to believe that our genes in large part determined our health and future development of disease. However, research in the past few years in the field of epigenomics has revealed that the expression of our genes is determined by the environment in which our cells live. The great news here is that our lifestyle choices can actually change our health for the better.

Unfortunately, the average American adult consumes significantly too much unhealthy fat, added sugar, red meat, processed foods and soda. These types of foods trigger the release of the hormones adrenaline and cortisol which are damaging to the body, especially to the brain. This high consumption of unhealthy foods together with low consumption of healthy foods high in antioxidants and polyphenols contributes to cognitive decline.

By comparison, studies done on diets in the regions of “Blue Zones” in the world (Ikaria, Greece, Nicoya peninsula of Costa Rica and Okinawa, Japan) have shown significant increases in longevity as well as preservation of cognitive function.  These diets are all high in fruits, vegetables and healthy grains and contain limited or no meat.  A study done at UCLA in 2014 showed that memory loss could be reversed using a lifestyle-based therapeutic program with a comprehensive change to the diet.  Another study at Rush University showed that participants (average age 81 ) who adhered to a healthy nutrition plan had a significantly reduced risk of dementia.

Several types of eating plans have been studied to see if they could be helpful in prevention of Alzheimer’s disease.

These are the Mediterranean diet, DASH diet for lowering blood pressure, the MIND diet, ketogenic diet, gluten free diet, and vegetarian diets. 

The Mediterranean diet was found to be highly beneficial in prevention of cognitive decline. Not only was the healthy food largely responsible for this decline but also the focus on being together with family and being in touch with nature was determined to be a factor.

The DASH diet was determined to be beneficial as well, largely due to the dietary shift from high fat, high sugar, and high red meat. The reduction in blood pressure as well was determined to significantly decrease the risk of Alzheimer’s.

Although the MIND diet showed some benefit, it was found to recommend too many grains to be highly effective in prevention. This was thought to be largely due to the increase in blood sugar due to high intake of carbohydrates.

Although ketogenic diets were found to have some advantages for memory, these diets are difficult to maintain and long term risks are unknown.  In particular, carbohydrates are needed for optimal health of the body and brain.  In addition, studies clearly suggest that diets high in saturated fat are not healthy in the long run.  However, ketones produced in this type of diet have been found to be protective for brain cells and also improve function of the mitochondria in the cells (the energy power plants within the cell).  Additionally, ketones have been found to decrease the accumulation of beta amyloid deposits in the brain.  Research is underway to determine whether a revised form of this diet may be beneficial.

Gluten free diets have not been shown to specifically reduce Alzheimer’s risk.  A study done by the Mayo Clinic found that a high carbohydrate diet increased the risk for mild cognitive impairment by 89%. Gluten free diets tend to lower blood sugar levels and it is thought that this effect may improve overall health. 

Vegetarian and vegan diets tend to decrease the incidence of both heart disease and cancer.  They may have some protective effect for developing Alzheimer’s.  However, the lack of consumption of meat and fish can be a concern as these diets tend to be missing in nutrients that are important for the health of the brain long term. This may be offset with supplementation of missing nutrients.

The most important takeaways from all of the above types of diets is that it is important to avoid a diet high in trans fat and saturated fat. These fats, such as those from animal products (especially red meats), cause inflammation and produce free radicals.  Free radicals are a normal by-product of metabolism, but in high quantities they can damage and even kill valuable brain cells.

Eating foods that are high in antioxidants like vitamins C and E is a wonderful natural way to eliminate free radicals from your body. In a similar way, scientists believe that a large intake of fruits and vegetables, eating fish rich in omega-3 oils and vegetarian protein substitutes (such as soy) are protective against memory loss.

What is the ideal diet for Alzheimer’s Prevention?

The ideal Alzheimer’s prevention diet includes the following:

• 20% “good” fats. Items in this group include extra virgin olive oil, avocado, and flax seed oil
• 40% lean proteins. Look to include fish, chicken, turkey, and soy on a daily basis.
• 40% complex carbohydrates. Discover the rewards of a rainbow of fresh vegetables, whole grains, legumes, and fresh fruits.
• Superfoods for the brain – as much as you want! These superfoods, including blueberries, greens, avocados, salmon and nuts have high amounts of antioxidants and protect your brain

Remember, perfection is not the goal. Any small improvement you can make in your diet will benefit you.

For this week, try adding some superfoods to your diet.  These could be berries, greens and healthy oils, specifically extra virgin olive oil. Try making a dinner salad daily and using olive oil instead of dressing. This can be as simple as some red leaf lettuce, some chopped celery and green peppers, sliced scallion, radishes and carrots.  Or try adding some blueberries to your morning granola or cereal. 

Next week we will look at recommended supplements and gut health.