How much forgetfulness is “normal”? Pioneering scientists chart the aging process.
Let’s face it: When we talk about aging, we tend to focus on the negatives. From aches and pains to memory loss, there’s so much to worry about as we grow older. But what if the advancement of the years didn’t have to be as debilitating as we sometimes imagine it to be?
We’ve got good news: When it comes to brain health, the future is bright. Very bright. Not just for younger folks, but for people in their 60s, 70s, and 80s, too.
Thanks to a number of landmark studies over the last decade or so, experts now believe there are numerous ways a person can increase their odds of holding onto cognitive function and avoiding diseases like Alzheimer’s over the years. The best part is that these strategies largely have to do with basic, accessible lifestyle choices, like sleeping more and drinking less alcohol.
Even more excitingly, there are a few scientists on the forefront of innovation who have begun to suggest that it might even be possible to reverse the effects of aging, simply by living a healthy life.
But before we get ahead of ourselves, let’s start with a breakdown of what, exactly, happens to your brain over time, according to a handful of experts — and then we’ll dive into the breakthrough studies that suggest your brain might just be capable of time travel. (Well, sort of.)
The four phases of brain deterioration (and when they happen)
Everyone’s aging process is different, but experts say most brains start to show some wear and tear between our 30th and 40th birthdays. One easy way to think about this process of deterioration is through four distinct phases, according to Dale Bredesen, MD, a renowned neuroscience researcher, author, clinician, and pioneer in the field of Alzheimer’s research.
In the first phase, usually during your 20s and 30s, your adult brain functions as it should, and you experience no negative effects whatsoever.
By your 40s and 50s, it’s common to experience some level of “subjective cognitive impairment,” notes Dr. Bredesen. “This is when you can’t always remember things the way you used to. You can’t remember names, your vocabulary is slightly changing, you can’t solve problems the way you did before … but you’re still able to score in the normal range.”
The third phase is mild cognitive impairment, and can often happen in your 60s and 70s. “By definition, now you are scoring abnormally on cognitive tests,” Dr. Bredesen says, “but you can still take care of yourself and do your daily activities.”
The fourth phase is dementia. “This is when you’re now having trouble doing your daily activities, you’re now having trouble paying bills, and you may have trouble taking care of yourself,” Dr. Bredesen explains.
As one approaches the upper 70s, 80s, and 90s, the brain usually begins to deteriorate at a more rapid pace. By age 85, the average person has a 50 percent chance of developing Alzheimer’s.
What’s happening physically as your brain gets older?
The brain ages in several different ways. Part of the process includes physical shrinkage, particularly in the frontal lobe and hippocampus. These are the areas of the brain that are largely responsible for cognitive function. While this shrinkage happens slowly at first, it starts to speed up after age 60.
There’s a whole list of other changes that are also happening within a deteriorating brain. This includes thinning of its outer layer, the loss of neurons, and the production of different levels of chemicals, some of which lead to a decline in cognitive function.
But perhaps one of the most important changes to the brain can be inflammation of the brain tissue, which is correlated with diseases like Alzheimer’s.
Brain health varies from person to person — and not everyone reaches the final stage of impairment
An important reminder: Brain health is extremely individualized. Deterioration happens at different ages and with different levels of severity for each person, depending on their genes, habits, and specific life experiences. In fact, brain health varies so much from person to person that it might be detrimental to benchmark your own milestones against anything other than your own personal journey.
“The most important thing we’ve learned about brain health as people get older is that there’s a lot of variability,” explains Marilyn Albert, Ph.D., a professor of neurology at Johns Hopkins and director of the Division of Cognitive Neuroscience. Amazingly, she adds, “Some people who are older perform cognitive tasks as well as individuals many decades younger.”
Consider the different phases of impairment as explained above by Dr. Bredesen: One important thing to understand, he notes, is that not everyone moves through all four phases.
For example, one person might spend 30 to 40 years with varying levels of subjective cognitive impairment but ultimately reach old age and pass away without ever progressing to the third and fourth stages. Another person might start showing signs of dementia in their 50s. It all depends on that strange cocktail of genetics and lifestyle that makes each person’s genetic makeup completely specific and unique.
Here’s where we get to the really exciting part: how certain lifestyle choices are proven to reduce inflammation in the brain and keep it as healthy as possible — and how these choices could actually even move you backward through the stages of impairment.
Can you reverse the effects of aging on your brain?
For a long time, scientists believed the aging process was irreversible. Now, a series of breakthroughs have led to a startling proposition: You might just be able to keep yourself cognitively sharp well into your old age — as long as you commit to certain lifestyle choices.
There is, of course, a caveat. As we mentioned above, everyone has a different brain and, therefore, a different brain journey. You can’t eat, sleep, or strategize your way into having someone else’s memory retention or mental acuity. You can only benchmark your progress against your individual brain health history.
But committing to long-term healthy lifestyle choices and sticking with them for decades can make a substantial difference, and that’s especially true for your vital organs, like your brain and your heart.
“In Alzheimer’s, the [building blocks for the disease can develop] 20 to 30 years before symptoms arise,” Rudolph Tanzi, Ph.D., a neurology professor at Harvard and the director of Alzheimer’s Genome Project, explains to Katie Couric Media. “Just like cholesterol can build up to heart disease. That’s why it’s so difficult to help Alzheimer patients with drugs: It’s like saying to a person with heart failure, ‘Yeah, just take Lipitor.'”
With that said, some scientists are even starting to believe that basic lifestyle choices could reverse the deterioration of your heart, brain, and other major organs. This dose of optimism is largely thanks to the work of one doctor, Dean Ornish.
Dr. Ornish is an internal medicine specialist who ran a groundbreaking study in 1990 which seemed to prove, for the first time ever, that it was possible to reverse the effects and severity of heart disease simply by altering a person’s diet, exercise, stress levels, and social support.
Ornish has since shifted his sights from the heart to the brain. Now he’s working to determine whether early-onset Alzheimer’s can be reversed with those same lifestyle interventions.
“What’s good for your heart is good for your brain and vice versa,” Dr. Ornish explained to CNN this summer. “Prior studies have shown moderate changes in lifestyle can slow the rate of progression of dementia and Alzheimer’s. So my hypothesis is that more intense lifestyle changes could stop or even reverse the decline.”
Dr. Bredesen, too, has run a similar study about lifestyle intervention. In August, he and a team of researchers published the results from a study in which they tested the effects of “diet, sleep, exercise, relaxation guidance, and supplemental probiotics and phytonutrients” to see how an improved lifestyle could impact someone’s biological age (which isn’t the same as their chronological age), and therefore their health. The results of the study showed a decreased biological age of 3.23 years for the test study group, compared to the control group.
In Dr. Bredesen’s bestselling book The End of Alzheimer’s, he shares more details about this lifestyle prevention approach. He told Katie Couric Media about an older woman who’d been on this program and gone from the 35th percentile on her cognitive testing to the 98th percentile, simply by shifting her lifestyle. “She’s sharp as a tack,” he said. Unsurprisingly, he received so many inquiries about lifestyle changes that he wrote another book, The End of Alzheimer’s Program, which is a great start for someone who wants to refocus on their health.
But what are those lifestyle interventions that Dr. Bredesen, Dr. Ornish, and others are talking about? They’re really targeted at improving the key factors of overall health: diet, sleep quality, social interactions, and more. By reducing stress, eating healthy food, and getting plenty of rest, you’re working to reduce inflammation in the brain, among other productive medical outcomes.
For diet, in particular, the Ornish meal plan revolves around the explicit requirement that no more than 10 percent of a person’s daily calories come from fat. Dr. Bredesen, on the other hand, suggests a plant-rich ketogenic diet. Of course, each person’s nutritional needs are different, so it’s most productive to meet with a doctor or nutritionist to figure out which specific diet is best for you.
The red flag that lets you know it’s time to see a doctor
While we understand that everyone’s brain matures at its own pace, there are ways to tell the difference between the elements of natural, relatively healthy aging and a sign that it’s time to see a doctor.
“All of us forget things from time to time,” Dr. Albert says. “But what raises a concern is when, having been reminded of something, the individual has no recollection of it. For example, if someone is reminded of a conversation that took place a week ago and can’t remember it at all.”
Another way to advocate for yourself, regardless of your symptoms (or lack thereof), is to ask your doctor about a cognoscopy.
“Everyone should get a cognoscopy if they’re 45 years of age or older,” Dr. Bredesen says. “The test is a pretty easy thing to do: It’s a series of blood tests, then a simple online cognitive test, and then the third part is an MRI scan of your brain.” This will help you get a better picture of your brain health — which is especially important since, as Dr. Tanzi noted above, the signs of neurological diseases tend to build for decades before showing up as outward-facing symptoms.
Lastly, as literally all of the doctors we spoke to pointed out, remember that the best form of protection for your brain is a proactive one. Don’t wait for the red flags to start treating your brain, heart, and other vital organs the way they should be treated throughout your life.
Want even more must-read insights on how to keep your brain at its best? Check out our entire Inside Your Mind series right here.
