Whether it's short-term stress (17 people are coming for Thanksgiving dinner and your oven just went on the blink) or long-term (a loved one is seriously ill), the body releases powerful fight-or-flight stress hormones (adrenaline and cortisol). While these hormones do sharpen attention and spur us to take needed action, humans weren't designed to handle high levels of stress hormones day after day, year after year. Indeed, in the brain they weaken blood vessels, kill off neurons and even shrink the hippocampus, a known risk factor for late-life Alzheimer's disease.
How does stress do its dirty work? The exact link between stress and aging-related illnesses like dementia eluded scientists for years until a study at the University of California, San Francisco in 2004 turned up a striking finding: chronic psychological stress speeds up the normal aging of a person's cells.
For their study, Elissa Epel, an assistant professor of psychiatry, and Elizabeth Blackburn, a Nobel Prize-winning molecular biologist, compared mothers who were caring for chronically ill children-clearly a group under severe stress-to a control group of mothers with healthy kids. Those who had been caregivers the longest had the lowest levels of a crucial enzyme called telomerase, which keeps cells healthy by repairing age-related damage to the tips of chromosomes. In fact, blood tests showed that some of the mothers who had been caregiving the longest were, on a cellular level, 10 years older than their chronological age.
But the news on the stress-brain connection isn't all bleak, says Epel: There have been heartening developments, too. Stress per se isn't the enemy of brain health, experts note; the way we perceive and handle it matters a lot, too. In fact, research shows that stress-reduction techniques, coupled with exercise and a healthy diet, can slow or even reverse the damage inside cells.
How do you begin to dial down your stress? Try the following five strategies.
Rx No. 1: Get to know your stress response.
Before you can tame tension, you need to understand what triggers it. But getting at that isn't always as simple as it sounds. Thanks to a mix of genetics, hormones and cultural factors, stress affects everyone differently: Something that ratchets up your stress level may not faze your best friend. Gender also makes a difference: A man's blood pressure spikes more sharply under stress than a woman's, though she may feel jolts of stress more often, and about more things.
Also, stress symptoms can be so subtle-a knot in the stomach or a tightening of the throat-that you may not even register them as such, especially if unaddressed stress is a constant in your life.
Tip
Do a personal body scan. Does your heart race? Do you struggle with a pain in your gut that antacids can't quell? Do you often forget or misplace things, or find yourself barking at people for no good reason? All of these may be signs of stress. Try to home in on what might be triggering it: a call from a sick parent? Another spat with your spouse? Keeping a daily log can help you spot patterns, and be sure to consult your physician to rule out serious health issues.
Rx No. 2: Move it!
"Exercise is essential for anyone under chronic stress, and that includes most of us," says Epel. Exercise short-circuits the stress response by triggering the release of BDNF (brain-derived neuropathic factor), which nourishes cell growth, as well as endorphins (serotonin, dopamine and norepinephrine), brain chemicals that boost feelings of well-being, ease muscle tension and improve sleep. (See No. 3 below.)
Tip
The cognitive functions and brain regions showing the most significant decay in late adulthood are the same regions that may benefit the most from exercise, says Benjamin L. Willis, M.D., an epidemiologist at the Cooper Institute in Dallas and coauthor of a long-term study highlighting the importance of exercise in reducing dementia risk.
So don't procrastinate: Carve out 150 minutes a week of moderate aerobic exercise. Couch potatoes should start slowly-10 to 15 minutes every other day, working up to 30 to 45 minutes, five days a week. After all, you're not competing in Olympic trials. Just walk briskly, jog, swim or bike-anything you enjoy doing that gets your heart pumping a bit faster and makes you break a sweat.
A study by Scottish researchers found that simply strolling through a green leafy park, as opposed to the concrete jungle of a busy city, actually lowers cortisol levels in the brain, easing "brain fatigue."
Don't forget resistance training (20 minutes every other day, using exercise bands or light weights) to boost muscle tone, balance and flexibility as well as your brain's gray matter. Never done any of that? You can sign up for an orientation class at a health club, but push-ups (on the floor, against a wall) and squats in your living room work, too.
Rx No. 3: Sleep on it.
"Sleep loss means mind loss," says John Medina, director of the Brain Center for Applied Learning at Seattle Pacific University and author of Brain Rules. "When you sleep poorly, your mood, memory, creativity and problem-solving capabilities [all] suffer."
A good night's sleep can help decrease the risk of dementia. "Sleep turns off the toxins that build up in the brain and ultimately lead to Alzheimer's disease," says Harvard neurology professor Rudolph Tanzi, coauthor of Super Brain: Unleashing the Explosive Power of Your Mind to Maximize Health, Happiness and Spiritual Well-Being.
Though neuroscientists have long suspected that the poor sleep seniors often experience contributes to age-related cognitive decline, they weren't sure exactly what went wrong or why. Recent studies at the Sleep and Neuroimaging Laboratory at the University of California, Berkeley point to structural changes in the middle frontal lobe of the brain that develop slowly as we age. These changes interfere with the deep, restorative sleep necessary for the formation of long-term memories.
Tip
How much is enough? There's no magic number, but the National Sleep Foundation suggests adults aim for seven to nine hours of uninterrupted sleep each night. Stick to a regular schedule, going to bed and waking up about the same time every day. If sleep escapes you, don't toss and turn in bed. Get up, read a book or listen to music until you start to feel sleepy. Avoid smoking and eating or drinking caffeine or highly acidic foods two to three hours before bedtime, and unplug from all technology-TV, computers and cellphones-at least 30 minutes before lights-out. Make your bedroom a sleep sanctuary, using the bed for sleep and sex only. Lower the temperature, install blackout shades and invest in a sound machine to drown out interfering noise. Still wide awake? Relaxation techniques such as yoga, meditation and guided imagery (see below) may also help.
Rx No. 4: Try meditation.
Over the years, researchers have linked different forms of meditation to cardiovascular health, pain relief, a healthy immune system and stress reduction. Now, they're discovering it also changes the very structure of the brain and may help preserve cognitive function.
Researchers in the Psychiatric Neuroimaging Research Program at Massachusetts General Hospital took MRI scans of a small group of people with no meditation experience before and after they enrolled in an eight-week mindfulness stress-reduction program. The results were remarkable: Compared to a control group, meditators showed an increase in gray matter in the hippocampus (devoted to learning, memory and attention) and a decrease in gray matter in the amygdala (the part of the brain associated with emotions, anxiety and stress). In a different study with experienced meditators, meditation also appeared to slow down the normal thinning of the walls of the brain: Gray matter in some brain regions of the 40-to 50-year-olds was similar in thickness to that of their 20-year-old counterparts.
According to study coauthor Sara Lazar, an instructor at Harvard Medical School, "Participants reported feeling less stressed after the program. This was correlated with a change in brain structure, which suggests that they were not just imagining it. Their brains actually are different."
Tip
There are many types of meditation.
Mindfulness focuses attention on the present, helping you observe problems without reacting emotionally to them.
Transcendental meditation uses a mantra (a special word) as a focal point to quiet the mind.
In guided imagery or visualization, you are led by a teacher (in class or on tape) to tap all your senses and imagine a calm, relaxed state.
Tai chi and yoga incorporate deep breathing and meditation into various poses.
There's no right or wrong way to meditate, nor is one method better than another. Try different types until you find one that works for you. (Check your public library or online for books and tapes to get you started as well as classes at a health club or senior center.) Be patient with yourself since it may initially feel silly, even unsettling, to disengage from the busyness of your mind. Ideally, set aside at least 15 to 20 minutes twice a day to meditate. But even a five-minute break to sit quietly, feet planted on the floor, breathing slowly and deeply from your abdomen, can break the gridlock of stress.
Rx No. 5: Fret less.
The worst stress is triggered by situations that leave you feeling powerless, whether it's a demanding job with lots of responsibility but few rewards, a tanking economy that takes a big chunk of your retirement savings, or caring for an ill spouse. But just fretting itself can decrease physical and psychological well-being. Researchers at Ohio University in Athens found that dwelling on upsetting events ratchets up levels of inflammation throughout the body, leaving you more susceptible to age-related diseases, including dementia, and making you more vulnerable to future stressful events small and large.
Tip
Chronic worriers have a perpetual ticker tape of anxiety running through their minds. If you're one of them, schedule a worry break: Set aside 15 minutes a day to actively dwell on problems and concerns. When that time is up, though, tell yourself to STOP (or picture a large red stop sign). Or try keeping a "worries" journal for one week. You may be surprised by how many of the things you lost sleep over never happened.
Meanwhile, do what you can to take charge of stressful situations. Anxious about finances? Consult a financial planner. Nervous about the outcome of a medical test? Pass the time until you get the results by going to the movies, reading an engrossing book or exercising. Or talk to people who have had a similar situation turn out well.
Finally, instead of allowing your to-do list to take over your life, reconsider what's on it and prioritize. Must you pick up the dry cleaning today or can it wait until tomorrow? Do you really have to prepare your famous lasagna for the church potluck or can you pick up a rotisserie chicken at the market on your way over? Honestly, no one's keeping score.
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