Share this article on:

Protect Your Brain for Life: Follow these expert strategies to guard against injury and cognitive decline throughout your life.

Cohen, Marisa

doi: 10.1097/01.NNN.0000513028.61644.81
Features: Brain Health

If you could peek inside your brain at every birthday, you'd see that it's constantly changing. Brain cells develop and disappear, the connections between them strengthen and weaken over time, even the size of the brain can change as the years go by. But keeping the brain in peak condition is something we tend to think about only at the beginning of life (Which educational toys are best for my baby?), the end of life (How can I stave off dementia?), and when something goes wrong (How do I reccover from a traumatic brain injury or stroke?).

“It's never too early or too late to start protecting your brain,” says Gary Small, MD, professor of psychiatry and director of the UCLA Longevity Center at the Semel Institute for Neuroscience and Human Behavior. While it's true that certain stages of development are more critical than others, stress and injury to the brain at any age can have long-term effects, he says.

Decades of research show that the ways we maintain good heart health—exercise, nutrition, and controlling high blood pressure, diabetes, and cholesterol levels—are also crucial to brain health. Here's what's going on in your brain at crucial stages of life, and smart habits you can adopt to keep it in top shape.

Back to Top | Article Outline

Keep in Mind

It's smart to take care of your brain, but that doesn't guarantee you won't still develop a neurologic illness such as Alzheimer's disease.

The relationship between lifestyle changes and brain health is not always well understood. Moreover, these relationships can be complex and may change as a function of age, especially as they relate to Alzheimer's disease, says John C. Morris, MD, FAAN, director of the Knight Alzheimer Disease Research Center in St. Louis. For example, obesity in middle age may be a risk factor for Alzheimer's disease in late life, but in older adulthood, loss of weight is associated with a greater risk for the disease, he says. The same is true for high blood pressure: In midlife it is associated with greater risk for Alzheimer's disease, but in late life it's associated with less risk.

As much as we wish it weren't true, some people who exercise regularly, eat a heart-healthy diet, avoid brain trauma, engage in mentally challenging activities, and stay socially connected still develop Alzheimer's disease. The disease is very complex, Dr. Morris notes, and we simply do not fully understand how it develops.

Back to Top | Article Outline

LIFE STAGE: Childhood (birth to age 12)

BRAIN ACTION: The first few years of life are spent furiously growing brain cells and developing connections, called synapses, between them, until you peak at more than 100 billion neurons and 100 trillion synapses in late childhood, explains Frances E. Jensen, MD, FAAN, chair of the department of neurology at the Perelman School of Medicine of the University of Pennsylvania. (A 2-year-old has about twice as many synapses as an adult.)

“All the cellular machinery that's required for learning is set at a higher level in children and adolescents compared with adults,” Dr. Jensen says, which explains why children are so naturally curious and quick to pick up new skills like languages and music.

HEIGHTENED RISKS: Synapses can either be switched on (excitatory) or off (inhibitory), says Dr. Jensen. During childhood and adolescence, the majority are in the on position, which makes it such a fertile time for learning—but may also make it a time of increased risk for epilepsy and autism, possibly due to an overload of excitatory synapses, says Dr. Jensen.


Play it safe. Any time your child rides a bike, skateboards, or does any activity that could cause a fall, make sure he or she is wearing a helmet that fits correctly and is in good condition. Ask the store clerk to fit the helmet before you leave, and always replace the helmet after a fall or if it's cracked or missing padding. (If you live in Minneapolis and like to shop at the farmer's market on Saturdays near the headquarters of the American Academy of Neurology [AAN], you may be able to pick up a free bike helmet as part of the AAN's campaign to raise awareness of brain safety.)

Stick to playgrounds that have soft surfaces under monkey bars, swings, and slides to cushion falls, as well as guardrails to keep kids safe. If your child does experience a fall, check immediately for signs of concussion, including vomiting, headache, drowsiness, and asymmetric pupil size, and call 911 or bring your child to the emergency department immediately.

Serve a brain-healthy breakfast. Establishing good eating habits in childhood will impact your children for the rest of their lives. Incorporate whole grains, fruit, and eggs into meals. Eggs in particular are a great source of choline, a nutrient that is critical for brain development, nerve impulse transmission, and memory, according to research published in Journal of the American College of Nutrition in 2013. You can also get choline via spinach, liver, cauliflower, and Brussels sprouts, but unless your child is a truly adventurous eater, eggs are probably your best bet.

Create a cozy bedtime routine. When children snooze, the connections between the left hemisphere (responsible for math, logic, and language processing) and the right hemisphere (involved in the more creative, artistic functions) grow stronger, helping the brain mature, according to a study published in the journal Brain Sciences in 2013.

Sleep is particularly important—and often much more of a challenge—for children with neurologic disorders such as epilepsy. The best way to encourage children to get the optimal 11 to 12 hours of shut-eye per night is to have a regular bedtime, even on the weekends, and a consistent routine, such as a bath, then a story and a lullaby. A large study published in the journal Sleep last year found that children with a bedtime routine fell asleep faster, slept an average of one hour longer, and woke less often during the night than those who didn't have a routine.

Get the lead out. Although lead poisoning has been greatly reduced in the United States over the past few decades, it's still a risk for some children. A report published in 2016 in the Journal of Pediatrics found that children who eat paint or soil, spend time outside the United States, or have a developmental delay or sickle cell disease may be at increased risk of lead poisoning.

Although lead-based paints have been mostly outlawed, several municipalities have detected lead in their water supply when old pipes or fixtures corrode. If your home was built before 1978, have it tested for lead; don't let children play in areas with chipping paint; and run the water for a few minutes before cooking or drinking. If you're concerned, ask your pediatrician to run a simple blood test for lead levels.

Expose your child to music early. A study from Northwestern University published in the Journal of Neuroscience in 2014 found that after at-risk children participated in a community music class for two years, the precision with which their brains processed sounds improved; researchers theorize this could lead to better learning and language skills. Enroll your child in piano, violin, or ukulele lessons, sign up for a youth choir, or take your little ones to a mom-and-me music class.

Back to Top | Article Outline

LIFE STAGE: Adolescence (ages 13 to 19)

BRAIN ACTION: In adolescence, the brain is refining and paring down cells and strengthening connections. “We call this process pruning, and it's ‘use it or lose it’ based on your environment and experience,” says Dr. Jensen. During this period, the brain is rapidly producing myelin, a protein that insulates the axons, the fibers that extend from neurons, so the different parts of the brain can communicate with each other at optimal speed.

HEIGHTENED RISKS: Adolescence is one of the most important periods for brain development, but it's also the riskiest. The myelin tracks that are created more toward the back of the brain—the areas that spark risk-taking, emotion, and sexuality—are developing much faster than front-of-brain functions such as reasoning, judgment, and impulse control. “There are more synapses, but they aren't connected to the frontal lobe, which tells the impulsive part of the brain, ‘Bad idea, don't do that!’” says Dr. Jensen. Add the typical peer pressures of high school, and addiction becomes a particular risk.

The late teens and early 20s are also the time when many mental illnesses and psychiatric disorders, including depression, schizophrenia, and bipolar disorder, come to the surface. Many of these conditions involve dysfunctions of the prefrontal cortex, the area of the brain responsible for personality expression, decision-making, and moderating social behavior. And while you may be born with a genetic predisposition to one of these diseases, the symptoms won't appear until the prefrontal cortex is mature and connected to the rest of the brain, says Dr. Jensen.


Schedule regular family meals. Teens are more likely to binge drink than adults, and the effects of alcohol on an adolescent brain can be devastating. A study from Duke University Medical Center published in Alcoholism: Clinical & Experimental Research in 2015 found that repeated alcohol exposure during this stage results in long-lasting changes in the part of the brain that controls learning and memory.

One surprisingly simple way to keep your kid from the temptations of alcohol and drugs: Eat dinner together. Teens who had fewer than three family dinners a week were almost four times more likely to try tobacco, more than twice as likely to use alcohol, and two and a half times more likely to use marijuana than teens who dined with their families at least five times a week, according to a 2012 report based on a national telephone survey of more than 1,000 teenagers conducted on behalf of Columbia University's National Center on Addiction and Substance Abuse.

Encourage sports, safely. Much has been written lately about the devastating effects of concussions on teen athletes. Traumatic brain injuries can cause changes to thinking, memory, and language, and can lead to epilepsy, Parkinson's disease, and other neurologic conditions, according to the US Centers for Disease Control and Prevention (CDC). But the benefits of team sports—for cardiovascular, brain, and social-emotional health, avoiding addiction, and gaining a sense of community and accomplishment—outweigh the risks, says Sandra Bond Chapman, PhD, chief director of the Center for Brain Health at the University of Texas at Dallas.

Sticking to non-contact sports such as track and swimming is one way to protect the brain, but even if your child plays football, ice hockey, or soccer, the key is to use the proper protective equipment and to recognize and treat concussions as soon as they happen. “We know what to do if you tear a ligament or break an ankle, but too many head injuries go ignored and untreated,” Dr. Chapman says.

The most important thing is to take the athlete off the field immediately. A 2013 report from the Institute of Medicine warned against a culture of “playing through the pain,” and pointed out that injuring the brain again before it has had time to rest and heal can be devastating or even fatal.

Get the meningitis vaccine. Young people between ages 16 and 23—especially those living in large groups, such as at a sleepaway camp or in a college dorm—are at increased risk of contracting meningitis, which can cause brain swelling and seizures and can lead to permanent brain damage if untreated. That's why the CDC recommends all 11- and 12-year-olds get the vaccine, plus a booster shot at age 16.

Turn off tech before bed. It was hard enough for teenagers to get their recommended nine hours of sleep each night before the age of Instagram and Snapchat; now many are up all night watching videos on their phones and chatting with friends. Sleep deprivation can lead to depression and more impulsive behavior, says Dr. Chapman. Make it a house rule that everyone—including parents—leaves phones out of the bedroom at night and turns off all electronic devices.

Stock your fridge with herbal iced teas and fizzy water. Adolescence is a vulnerable time for weight gain, which can begin a lifelong battle against obesity. What's more, an Italian study published in 2015 in Pediatrics found that obese and overweight adolescents had higher levels of certain molecules circulating in their blood that are associated with cognitive decline later in life. Keep drinks with added sugar, such as sodas and energy drinks, out of your house; instead, encourage your kids to drink unsweetened herbal iced teas and carbonated water.

Back to Top | Article Outline

LIFE STAGE: Adulthood (ages 20 to 39)

BRAIN ACTION: As you pass into adulthood, the different areas of the brain become even more interconnected, creating a system of checks and balances for all those emotional impulses. In the meantime, more myelin is deposited around the axons, speeding up communication throughout the brain and helping with reasoning and planning, says Dr. Small. This process continues through around age 40. “The speed at which we can communicate information throughout the brain is increasing, peaking in middle age,” he says. Otherwise, this is a time when brain activity is leveling off—no longer the rapid development of youth and not yet the decline of advanced age—unless you have a genetic predisposition to a condition such as multiple sclerosis, which can appear during adulthood.

HEIGHTENED RISKS: While this is a stable age for brain development, it can be a very stressful time in life. “There is a lot of pressure as you're trying to establish yourself and become independent, get a foothold in your career, and find a partner, and stress can have a big impact on your overall health, including the brain,” Dr. Small says.


Adopt a stress-relief practice. New research shows that stress, fear, and anxiety can affect the brain, leading to a greater risk of dementia and other disorders later in life. “Chronic stress and anxiety cause the brain to release excess cortisol, and that affects the hippocampus, the part of the brain responsible for forming new memories,” explains Linda Mah, MD, assistant professor of psychiatry at the University of Toronto. “More recent research shows how stress also affects the prefrontal cortex, which is the part of the brain responsible for executive function, and also regulates the stress response.”

Other researchers have found that stress can cause pre-mature shrinking of the telomeres, a part of the chromosome that gets shorter as you age, and a decrease in klotho, a hormone that regulates aging and provides resilience against many toxins in the brain, including the ones that lead to Alzheimer's disease. Even if you can't eliminate the stress caused by your job or relationships, you can change how it affects your mind and body. Several studies, including one from Carnegie Mellon University published in 2015 in Current Directions in Psychological Science, show that mindfulness meditation, which focuses on breathing and body awareness, can effectively lessen the body's response to stress.

Quit smoking. If you picked up smoking as a habit during those reckless teenage years, now is the time to get serious about quitting. Not only does smoking greatly increase your risk of stroke, which can lead to brain damage and vascular dementia, but a study from McGill University published in 2015 in Molecular Psychiatry shows that long-term smoking can cause thinning of the brain's cortex, the outer layer of the brain where critical cognitive functions such as memory, language, and perception occur. And it's never too late to quit: The earlier you quit smoking, the sooner that layer starts to rebuild.

Exercise outdoors. Exercise is one of the most important ways to keep your brain healthy. It has been shown to create new neurons in the hippocampus, says Dr. Mah. Outdoor activities like jogging, playing tennis, or riding a bike have the added benefit of exposing you to sunshine and upping your stores of vitamin D.

While some research has found a correlation between lack of vitamin D and risk of dementia, more research needs to be done, says Dr. Chapman. What we know for sure is that exposure to sunshine can stave off depression and improve sleep, both of which translate to a healthier brain, she says.

Eat your berries and greens. A review of the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet—a combination of the Mediterranean diet and the heart-healthy DASH diet—published in 2015 in Alzheimer's and Dementia showed that two types of food have a particularly strong effect on the brain, slowing cognitive decline: berries and leafy greens.

Strawberries, blueberries, and other berries contain polyphenols, which help protect the brain against the type of oxidative damage that is more prominent in people with Alzheimer's disease. Leafy greens such as spinach, kale, and Swiss chard are rich in vitamin K, which may also have a protective effect on the brain. Try to include greens on your plate once a day, and sprinkle berries on your breakfast or dessert a few times a week.

Put down the phone when working. If you're in the habit of trying to accomplish three things at once, slowing down to focus on one task at a time can benefit your brain, says Dr. Chapman. “We're learning that multitasking is to the brain as cigarette smoking is to the lungs,” she says. “Chronic multi-taskers have shallower thinking and may be less able to see the bigger picture. Multitasking can also impair sleep patterns, affect memory, and degrade brain systems,” she adds.

Back to Top | Article Outline

LIFE STAGE: Middle Age (ages 40 to 64)

BRAIN ACTION: While myelin development typically has peaked by this stage, you can still continue to strengthen your brain's connectivity by constantly challenging yourself, says Dr. Chapman. You may also start experiencing the occasional memory blip, such as forgetting a neighbor's name or misplacing your keys, but this isn't necessarily a cause for concern, says Dena Dubal, MD, PhD, assistant professor of neurology at University of California, San Francisco.

“Changes now tend to be in the frontal lobe, which is responsible for executive function—focus, attention, the ability to hold a thought in the mind while doing something else,” she says. This is a great time to get serious about brain health and make your brain more resilient against future deficits, says Dr. Chapman.

HEIGHTENED RISKS: All the health risks of middle age—obesity, high cholesterol, high blood pressure, onset of diabetes—can affect brain health.


Think harder. One of the most effective ways to exercise different areas of the brain, keeping those lesser-used synapses strong, is to stretch your thinking in practical ways, says Dr. Chapman. This can mean anything from reading editorials that clash with your own political point of view and finding ways to see from the author's perspective, to watching and interpreting movie genres you aren't typically drawn to.

You may even want to take up a new language, if you can use it in a meaningful context like traveling to a different country. A 2014 study published in Annals of Neurology by researchers at the University of Edinburgh found that becoming proficient in a new language in middle age had some protective effects against age-related cognitive decline, especially in reading and verbal fluency.

Take control of diabetes. Scientists have long seen a connection between type 2 diabetes, which tends to appear in the early to mid-fifties, and the onset of dementia, especially among those who have serious complications. But a large German study published in Annals of Neurology in 2013 showed that when people effectively controlled their diabetes with medication, their risk of dementia was cut in half. If you have diabetes, check in with your doctor to make sure you are on the best regimen for controlling your blood sugar.

Get serious about weight loss. A 2012 study from the French National Institute of Health and Medical Research published in Neurology found that even when obese middle-aged adults were metabolically healthy, meaning they did not suffer from high blood pressure, diabetes, or other serious health conditions, they still had increased cognitive decline over the course of 10 years. Researchers in Australia have also found a connection between increased body weight and a decreased size of the hippocampus, an area of the brain important for learning and memory. Commit to cardiovascular exercise for at least 30 minutes three times a week, and talk to your doctor about losing weight through a healthy diet or bariatric surgery, if appropriate.

Solve your sleep apnea. Around 25 million Americans have sleep apnea, a condition in which breathing stops up to dozens of times a night because of obstructed airways. A study from New York University School of Medicine published in Neurology in 2015 found that adults with sleep apnea experience cognitive decline at an earlier age than those without sleep disorders. Losing weight may resolve the problem; you can also contact a sleep specialist to discuss using an oral appliance or a continuous positive airway pressure machine, a mask that blows air through the mouth and nose to keep the airways open at night.

Reassess your workplace. A Florida State University study published in 2016 in the Journal of Occupational and Environmental Medicine found that two job-related factors can lead to cognitive decline: a lack of challenge and change in your work, and a dirty work environment. If you're coasting in your job, ask to take on more responsibilities or consider taking outside classes to learn new skills—which you can either use in your current job or to find something more stimulating— and make sure your office or workplace is cleaned regularly.

Back to Top | Article Outline

LIFE STAGE: Older Age (ages 65 and above)

BRAIN ACTION: Certain changes in the brain are inevitable as you age: The prefrontal cortex and the hippocampus, both of which are important for memory, planning, and learning, begin to shrink. Some of the myelin-covered axons that you spent the first half of your life developing may begin to degrade, and blood flow in the brain can decrease as arteries narrow. However, the healthier you keep your body and the more you challenge different sections of your brain, the longer you can keep it functioning well, says Dr. Chapman. “When people engage the parts of their brain that are still healthy, they can help push back the more severe cognitive loss by two to three or even five years,” she says.

HEIGHTENED RISKS: Risk for Alzheimer's disease and other forms of dementia increases at this stage, as well as risk of stroke. One in nine people over age 65 develop Alzheimer's disease, and by the time you turn 85, the risk is one in three. As your body becomes frail, you also increase your risk for falls, which can jeopardize brain health.


Call at least one friend a day. The more friends and family you keep in touch with, the more outlets you'll have to exercise your brain in conversation, and the more opportunities you'll have to participate in stimulating activities. In fact, a Dutch meta-analysis published in 2015 in Ageing Research Reviews found that low social participation, less frequent social contact, and loneliness were comparable to other well-known risks of dementia, including physical inactivity and late-life depression.

Get smartphone savvy. While too much technology can be detrimental to the developing brain, learning how to call an Uber so you can attend a lecture at your library, playing trivia games on your phone, or learning how to share photos of your grandchildren on Facebook can be an important tool in staying socially and mentally active, says Dr. Small.

Do something different once a week. “In retirement, people often go on autopilot,” says Dr. Chapman. “They have the same lunch every day, celebrate their birthday at the same restaurant with the same people every year.” But by innovating in little ways—exploring a new city, a new part of town, or a new recipe, for example—you may be able to stimulate norepinephrine, a power-ful neurotransmitter that, among other things, increases motivation, alertness, and speed and retention of learning, she says.

Walk it out. Research from the University of Maryland published in 2015 in the Journal of the International Neuropsychological Society found that moderate exercise such as walking helped to reverse shrinking of the brain's outer layer in both healthy seniors and those with mild cognitive impairment. Even walking as little as 15 minutes a day can help, says Dr. Small. Strength training is also important in maintaining brain health, so if you're wheelchair-bound, enroll in a seated exercise class.

Keep your home safe. Falls are the leading cause of traumatic brain injury, and the risk of a fall greatly increases after age 75. Make sure you aren't on any medications that make you dizzy, that your eyeglass prescription is up-to-date, and check your home for tripping hazards such as cords, throw rugs, and loose railings.

Adults with mild cognitive impairment who sustained head trauma had a higher level of amyloid deposits than those who did not report head injuries, demonstrating a possible link between brain injury and the development of Alzheimer's disease, according to a Mayo Clinic study published in 2013 in Neurology. (For more tips to prevent falls, see

© 2017 American Academy of Neurology