Over 40 million people globally are affected by Alzheimer’s disease. It’s the most common form of dementia in the world, according to Alzheimer’s Disease International. In America, it’s the sixth leading cause of death, according to the Centers for Disease Control and Prevention. The prevalence rates tend to be highest in North America and northern Europe and lowest in Asia and the Mediterranean region, leading researchers to wonder what the reason is. Furthermore, previous studies have shown Alzheimer’s disease to be associated with obesity, high blood pressure, high cholesterol, cardiovascular disease, and diabetes. Putting these and other findings together, doctors came to the conclusion that Alzheimer’s disease is caused by a mix of genetic, environmental, and lifestyle factors.
Currently, there is still no cure for or drug to stop Alzheimer’s disease. However, it may be possible to hold off dementia—even in people who have a genetic risk, according to a report presented by researchers at the Alzheimer’s Association International Conference. The way involves a set of healthy lifestyle choices. The results of several studies combined show that by adopting as many of the healthy habits as possible, it greatly lowers the risk of cognitive decline. One of those studies found that the reason people in the Mediterranean and Asia have lower prevalence rates than the rest of the world is because of their diet, which is one of the factors to follow.
The lifestyle behaviors include regular exercise, cognitive stimulation, a brain-healthy diet, and not smoking. People who followed four out of five of these factors will benefit. In one study by Rush University in Chicago conducted over a six-year period, participants had a 60% lower risk of developing Alzheimer’s dementia when compared to people who practiced only one or none of these habits. A second study on the matter conducted in the UK found that among people with a heightened genetic risk of cognitive decline, dementia was 32% lower in those with a healthy lifestyle. A third similar study conducted by the University of California in San Francisco found that smokers had twice the risk of developing cognitive impairment compared to non-smokers and those who had kicked the habit.
Dr. Ronald Petersen, director of the Mayo Clinic Alzheimer’s Disease Research Center who was not affiliated with the studies, said, “This reinforces the notion that some of these lifestyle factors may actually affect the trajectory of cognitive aging and the development of dementia. We certainly accept that with heart disease. We need to adopt a similar mindset for cognitive aging. For people who fear dementia is inevitable because of family history or a genetic profile, this tells them the game is not over because they have increased risk.”
The first of the set of studies, the one by Rush University, analyzed data from 1,845 participants in the Chicago Health and Aging Project and 920 from the Rush Memory and Aging Project who had no dementia at the start. Each participant was given a lifestyle score. The final score depended on how many of five possible healthy behaviors they subscribed to. Each behavior got either a zero or a one, for a maximum possible score of five.
The behaviors included:
- Do not smoke
- Exercise at a moderate to vigorous level for at least 150 minutes a week
- Consume a brain-supporting diet (i.e., the MIND diet)
- Light-to-moderate alcohol consumption
- Engage in late-life cognitive activities
The British study involved 196,383 adult participants who were already participating in the UK Biobank and who were all at least 60 and didn’t have dementia at the beginning of the study. All of them were given a dementia risk score that was based on genes that had been shown to be associated with an increased risk of dementia, as well as a lifestyle score, which was higher depending on how many of the healthy behaviors they reported. The study went on for 6 years. By the end, 668 of the participants developed dementia. The likelihood was higher among those who had a high genetic risk score, although the risk was more than halved among participants with high genetic factors but who had followed a healthy lifestyle. In other words, for every 121 cases (over a 10-year period) of individuals with high genetic risk, 1 would be prevented from following a healthy lifestyle.
The MIND Diet
Now back to the diet factor, as mentioned before, Alzheimer’s disease rates are relatively low in Japan and in Italy. What the researchers found is that these diets share an emphasis on fruits, vegetables, beans, and fish and include little red meat. This led to the formation of the MIND diet—a brain-supporting diet.
Dr. Klodian Dhana told NBC News, “The MIND diet emphasizes 15 dietary components, including 10 foods to eat daily—green leafy vegetables, other vegetables, nuts, berries, beans, whole grains, fish, poultry, olive oil, and wine—and five foods to avoid: red meats, butter and stick margarine, cheese, pastries and sweets, and fried or fast food.”
The MIND diet (Mediterranean-DASH Intervention for Neurodegenerative Delay) is not something you do for a day here and there or for a month and then stop and so forth. You have to eat this diet consistently over the years to get the best protection. The longer and more consistently you do the right thing for the healthier you’ll be.
A study was conducted to verify the MIND diet. Participants were scored for how well they followed the diet. Those in the upper 40% (following the healthy food lifestyle at least 60% of the time) got a point, while those that did not got a zero. It went on for 6 years, and 608 out of almost 2,000 of the participants developed Alzheimer’s dementia. After analyzing all the people’s data, the researchers found that the risk of Alzheimer’s was 37% lower in people who practiced two to three healthy lifestyle behaviors and 60% lower in those who practiced four to five of those behaviors compared to those with scores of zero or one.
Conclusion
It costs less to just exercise and eat good foods rather than to have to buy lots of medicine and pay doctors bills later. Even though it doesn’t prevent dementia in everyone, it may delay it, and it will at least make everyone feel their best along the way! Bottom line, a reduced risk of dementia is associated with a healthy lifestyle regardless of genetic risk. At the same time, laboratory research into hidden biological drivers of Alzheimer’s continues to uncover new molecular targets that may one day complement lifestyle prevention. And with so few medications to treat Alzheimer’s, why not live healthy just in case?
The next question the researchers want to tackle is whether healthy lifestyle behaviors slow down the pathology that gunks up the brain in people with Alzheimer’s or simply make the brain more resilient to it, said Dr. Jason Brandt, a professor in the departments of psychiatry and behavioral sciences and neurology at the Johns Hopkins School of Medicine.
