There's no surefire way to prevent Alzheimer’s, but research shows you can take certain steps to lower your risk. Here's a look at approaches for Alzheimer's prevention and the science behind them.
Every year, more than 900,000 Americans are diagnosed with Alzheimer’s dementia. Only five percent of these cases are a result of a genetic form of early-onset Alzheimer’s, which is not preventable. For the other 95 percent of cases: Yes, it may be possible to reduce the risk of developing Alzheimer’s. Studies show that some percentage of Alzheimer’s cases can be prevented by healthy lifestyle changes, including dealing with treatable diseases and health conditions that are associated with dementia. There’s no guarantee you can prevent yourself from getting Alzheimer’s, but these lifestyle changes could help at least slow down the disease or delay its symptoms.
Can you prevent yourself from getting Alzheimer’s?
A number of treatable health conditions including high blood pressure, midlife obesity, depression, and hearing loss are all linked to higher rates of Alzheimer’s. Aspects of a person’s lifestyle, from exposure to air pollution, to low educational attainment, to smoking, are also known risk factors. And healthy lifestyle choices, like eating a healthy diet, getting exercise, taking the right medications, and staying mentally active are all associated with lower risk.
So, while there isn’t a silver bullet way to prevent Alzheimer’s, mitigating these risk factors prevent up to one in three cases of the disease.
1. A healthy diet full of nutritious foods may have some serious sway in preventing Alzheimer’s
The link between Alzheimer’s and your diet is complicated. Observational studies which look at diet over time suggest that it is an important factor.
Eating processed foods that are high in added sugar and fat — like chips and soda — is associated with brain shrinkage, faster cognitive decline, and Alzheimer’s. On the other hand, a diet which is rich in leafy greens, legumes, fish oils, whole grains, and nuts, may reduce the risk of cognitive impairment and Alzheimer’s while also promoting heart health.
The MIND diet combines a Mediterranean-style diet with the DASH diet which was designed to improve heart health.
“The MIND diet had a pretty dramatic effect,” the late Martha Clare Morris, ScD — who was a professor at Rush University and one of the creators of the MIND diet — told Being Patient in a previous 2018 BrainTalk. “We found that people who scored in the top third for closely following the MIND diet [via questionnaire] had very little changes in their cognitive abilities over time.”
Those participants who adhered to a MIND diet were about seven and half years younger in brain age compared to participants who did not eat foods associated with this diet.
“We found that people in the highest third of scores had a 53 percent reduction in the risk of developing Alzheimer’s,” Morris said. “Even people who were in the intermediate range for adhering to the diet still had a 35 percent reduction.”
Do ketogenic diets reduce the risk of Alzheimer’s?
There is a lack of evidence that the ketogenic (keto) diet staves off Alzheimer’s. The diet is supposed to work by helping the brain use fat as fuel instead of glucose making it more efficient.
“Sticking to a ketogenic diet might provide your body with a needed alternate source of energy,” Ed Blonz, Ph.D., a nutritionist and assistant clinical professor at the University of California, San Francisco told Being Patient in a previous BrainTalk. “But doing so could deprive the body and brain of many other essential nutrients that play a role in your overall vascular health.”
During the ketogenic diet, the body uses compounds called ketones for energy. Blonz explained that the ketones lower blood pH leading to other health consequences. “In addition to messing with the body’s acid-base balance, carbohydrates get cut out of a keto diet, or down to a minimum, and this pushes many healthful foods–fruits and healthy grains — off the plate,” Blonz added.
However, the ketones themselves may be beneficial. Blonz and other scientists are studying whether ketones could prove protective.
Can intermittent fasting reduce the risk of Alzheimer’s?
Fasting in intermittent intervals could promote longevity and healthy metabolism within the brain. A person will eat during an eight or six hour window throughout the day, fasting the rest of the time. During the fast, the brain enters a low-energy protective state. In this state called autophagy — a word derived from Latin, meaning “self-eating” — cells begin to recycle existing materials and clear waste.
While this approach worked in animal models, the evidence in humans is still lacking. “Fasting is not necessarily a good thing,” USC biogerontologist Dr. Valter Longo, founder of the Prolon fasting-mimicking diet said in a previous Being Patient Live Talk. “We need to find the type of interventions and the type of fasting that can work.”
Longo is currently running a study of 60 patients at the University of Genoa to see whether a particular type of fasting-mimicking diet intervention could improve brain health.
What about brain-boosting supplements?
Even though many Americans take them everyday, there is no evidence that supplements provide any benefits for the brain. Due to a lack of regulation, supplement products do not need to be tested for efficacy — sometimes even containing unmarked or illicit ingredients. Others like serine supplements may actually worsen cognitive health.
“Consumers need to avoid this whole category of brain-boosting supplements for two reasons,” Pieter Cohen, physician and associate professor at Harvard Medical School told Being Patient. “Number one, I’m not aware of any supplement ingredient that’s legal [and] can improve memory and cognitive function,” he said. “The second thing is that they may contain potent pharmaceutical drugs that are not approved for use in the United States.”
Will adopting a MIND diet lower my risk of developing Alzheimer’s?
The MIND diet is associated with a reduced risk of Alzheimer’s across many studies. While the evidence for this diet is strong, the cause and effect of this relationship isn’t clear yet.
“Many trials have not found that making people eat healthy … is translating into benefits in the ways that is expected from the epidemiological research,” said Dr. Hussein Yassine, associate professor of medicine and neurology at the Keck School of Medicine of USC, said in a press release at the time. “That means either there is no causal connection, or that these studies have not been properly designed.”
Race and socioeconomic factors are also associated with Alzheimer’s disease and diet. Black and Hispanic Americans, as well as people who earn less money are less likely to eat healthy and more likely develop other cardiovascular conditions and Alzheimer’s.
This makes it very difficult to prove that the MIND diet, and not other factors are responsible for this risk reduction.
That doesn’t mean a MIND diet isn’t worth it. It improves physical and cardiovascular health. There is also evidence that the MIND diet may reduce the likelihood of developing Alzheimer’s. Scientists just aren’t 100 percent sure yet.
2. Exercise may reduce the risk of developing Alzheimer’s
Exercise — even small amounts — can boost brain health. Aerobic exercise like running could lower the risk of developing dementia. Exercise doesn’t have to be intensive or time-consuming. Another option involves taking short breaks throughout the day. These small bursts of physical activity, called “exercise snacks” also reduce the risk of cognitive decline.
Even low-intensity exercise can reduce the risk of developing Alzheimer’s or dementia. This is great news for people who don’t have a lot of time, opportunity, or mobility to do intensive exercise. A study published in JAMA Neurology found that walking 4,000 steps a day reduces the risk of developing dementia by 25 percent.
When Jamie Tyrone found out she carried two copies of the APOE4 gene, greatly increasing her risk of developing Alzheimer’s. She founded an awareness organization called Beating Alzheimer’s By Embracing Science (BABES) and spoke with Being Patient about incorporating exercise for prevention. “I think I found a happy medium of moderate exercise and everything in moderation,” she said in a Being Patient BrainTalk. “If we address comorbidities, we will hopefully increase our cognitive reserve and push out Alzheimer’s by five years.”
Exercise promotes cardiovascular health. This helps keep the brain’s blood vessels intact, ensuring a steady flow of oxygen and energy. Exercise also stimulates the brain’s immune system and leads to the release of hormones and signaling molecules in the blood that may stave off Alzheimer’s.
“We found benefits when individuals exercised at least three times a week,” Scott Forbes, an associate professor at Brandon University who studies exercise, told Being Patient. “I believe all forms of exercise are beneficial but there does appear to be a greater benefit with higher intensity exercise.”
3. Treating cardiovascular conditions
High blood pressure, cholesterol, and diabetes in mid-life are all associated with an increased risk of developing Alzheimer’s disease and other dementias. These cardiovascular conditions are more common in Black and Hispanic Americans.
Treating these conditions involves a mix of exercise, diet, and medications. The medications used to treat these conditions are linked to a reduction in Alzheimer’s risk.
Blood pressure-lowering medications are prescribed when blood pressure reaches 130/80 mm Hg. Blood pressure medications that cross into the brain could reduce the chance of developing dementia by 19 percent.
Statins are another class of drugs that promotes cardiovascular health by lowering the levels of bad cholesterol in the blood. Getting cholesterol under control with statins is linked in some, but not all, clinical trials to a reduction in Alzheimer’s risk.Still, statins are linked to many other cardiovascular benefits.
Heather Ferris is a clinical endocrinologist and scientist at the University of Virginia who studies cholesterol metabolism and its relationship to Alzheimer’s. “Epidemiological studies showed that people taking statins were less likely to develop Alzheimer’s disease,” she said. “But people on statins are accessing the health care system, so there are a lot of other potential factors that could be playing a role in this difference.”
Wendy Nelson, Ph.D. is a leader in biotech who found out she carried two copies of the APOE4 gene. Being a scientist, Nelson wanted to do whatever she could to reduce her risk of developing the disease. “I have gone on low-level rosuvastatin to decrease cholesterol,” she said in a recent Being Patient Live Talk.
There is some evidence that diabetes treatments could help keep the aging brain. These drugs help get blood glucose under control, helping the brain maintain health metabolism for longer. Scientists are now testing whether these drugs could stave off cognitive decline in the early stages of Alzheimer’s.
4. Keeping the brain active protects against Alzheimer’s and cognitive decline
Low educational attainment, hearing loss, social isolation, and depression are major risk factors for Alzheimer’s that impact brain health and function. Keeping the brain sharp and healthy can help mitigate these risks.
Keeping the brain mentally active by reading or doing puzzles (even while sitting down) could reduce the risk of developing dementia. Even games like Super Mario Brothers or The Last of Us which aren’t designed to improve brain health still provide a protective boost. Musicians and people who speak more than one language are also less likely to develop Alzheimer’s.
Many older Americans with hearing loss could reduce their risk of developing Alzheimer’s through the use of hearing aids. Improving hearing ability makes it easier to engage in group settings and participate in other activities, such as playing music. All of these activities engage problem solving and memory, stimulating the process of neuroplasticity. Essentially, they help the brain strengthen existing connections and build new connections.
Depression and other psychiatric conditions during mid-life could increase the risk of developing Alzheimer’s or dementia. Depression could also accelerate the aging process in the brain, leading to earlier onset of dementia. There is also more overlap between depression and Alzheimer’s — three in five people diagnosed with depression will experience some form of cognitive impairment.
Fortunately, treating depression through a combination of lifestyle changes, psychotherapy, and antidepressant medications can lower the risk of developing Alzheimer’s as well.
The bottom line: Health-forward lifestyle changes can lower Alzheimer’s risk — and if you’re genetically predisposed to Alzheimer’s, they could at least help delay the disease’s onset.
Some people will get Alzheimer’s no matter how healthy their diet is and how much they exercise — this is the fate in our genetics. However, there are many different risk factors that increase one’s chances of developing Alzheimer’s. Many of them are modifiable, meaning that it is possible to lower the risk of developing the disease. And if you do have a higher genetic risk of developing Alzheimer’s, these lifestyle changes could help to delay the disease’s onset or slow the rate of cognitive decline. Don’t forget that, while Alzheimer’s affects one in 10 U.S. adults over the age of 65, many people live “normal” lives for years or even decades after an Alzheimer’s diagnosis.
The most successful approaches for reducing the risk integrate multiple approaches encompassing a healthy diet, exercise, managing cardiovascular health, and keeping mentally active. These healthy practices do not guarantee that an individual will not get Alzheimer’s.