Top Alzheimer's researcher explains how you can help protect your brain

Every 66 seconds, someone in the United States develops Alzheimer’s disease.

Currently, more than 5 million Americans live with the memory-robbing ailment and by 2050 that number could rise as high as 16 million, according to new figures from the Alzheimer’s Association.

Scientists are working to find ways to not only treat Alzheimer’s but prevent it from developing in the first place. In one key step in the process, researchers are gaining a better understanding of the role of amyloid proteins in the development of the disease.

“The amyloid plaques build up outside of the nerve cells [in the brain] and now we know that when the nerve cells interact with the plaque, it causes the nerve cell to make a tangle inside,” explains Rudy Tanzi, Ph.D., director of the Alzheimer’s Genome Project and a leading researcher in the field at Massachusetts General Hospital and Harvard Medical School. “And that tangle then chokes the nerve cell from within and kills it. So the killing process begins with the amyloid – that’s kind of the gun – but the tangle’s the bullet, so to speak.”

Experts now believe these amyloid plaques and the tangles they form start occurring in people’s brains 10 to 15 years before any symptoms like memory loss begin to show.

The latest drug development efforts are focused on intervening much earlier on, before the disease takes an irreversible toll on memory and cognitive function. Tanzi likened it to taking statins to manage cholesterol to prevent a future heart attack.

Another increasingly important focus of medical research is neuroinflammation in the brain — why it happens, and how to stop it. 

For patients with Alzheimer’s, Tanzi explained, “What’s killing most of your nerve cells is neuroinflammation, where the brain has reacted against all these plaques and tangles and cell death with an inflammatory response. And only over the last 5 years, we’ve discovered the genes that control neuroinflammation in Alzheimer’s and we’re doing drug discovery based on those as well.”

Yet, while such drugs can take years to develop, Tanzi says there are things people can do right now to help protect their brain. He spoke with CBS News chief medical correspondent Dr. Jon LaPook about these strategies.

Q: Aside from choosing the right parents, what can somebody do to prevent Alzheimer’s – or try to help prevent Alzheimer’s?

A: The four big categories are diet, exercise, sleep and stress reduction. I wrote about this in detail in my last book, “Super Genes” – six chapters, more than you wanted to know about how to adapt your diet to minimize inflammation and plaques. 

Meaning Mediterranean diet, probiotics – take care of your gut bacteria.

Q: Which probiotics?

A: Yogurt, a yogurt drink like kefir, or a probiotic pill with live bacteria.

Q: But there’s so many different ones ... which ones? Do we know yet? We don’t know yet.

A: It’s a hot area right now. There are companies that are looking at what are the best bacteria to put in a probiotic.

Q: Why would what’s going on in your gut affect what’s going on in your brain?

A: So it turns out there’s what’s called a gut-brain axis, where the bacteria in your gut are creating chemicals that interact with your brain that do everything from determine your mood to control how much inflammation there is in your brain.

Q: And even obesity, right? It’s amazing what we’re learning about these trillions of bacteria that people were saying, ‘Oh, wash them out … I’m going to get a cleanse. They’re icky! Let’s get them out of us!’ It turns out, of course, millions of years of evolution – they’re there for a reason.

A: And you want to take care of them. They’re there to help you. A Mediterranean diet, more fiber, more fruit, what are called prebiotics, probiotics – meaning, if you don’t know exactly what probiotic pill to take, at least live-culture yogurt. I drink kefir every morning.

And then after diet – exercise. You know at least an hour-long brisk walk, or try to get 8,000 to 10,000 steps if you’re using a device.

And sleep. Eight hours. After 40 years old, you have to get seven to eight hours of sleep, and try your best to do it because as you cycle in and out of REM sleep, this is when you clean amyloid plaque out of your brain.

Q: That was one of the most amazing discoveries, when I first read about that – you’re actually ‘garbage collecting’ at night when you’re asleep. The toxins get carried out of your brain.

A: The brain – first of all, the cells that can cause inflammation, when they’re behaving are clearing the plaque. So you want to keep these certain cells clearing the plaque away and not causing inflammation. During the deep sleep, those cells eat all the plaque. And then the brain literally, physically constricts itself and releases the plaque debris – the proteins from the plaque – into the spinal fluid and out of the brain to wash away.

You can actually see the brain physically constricting after the material’s been broken down by the resident cells. And this only happens during delta – slow-wave – the deepest sleep that comes in after REM. So you want to be able to cycle in and out of REM several times per night. Kind of like a dishwasher on multiple cycles, you want to go in and out to clean the brain as much as you can every night with sleep.

Q: So it’s coming down to what our parents told us, right? Eat your fruits and vegetables, get a lot of exercise, get plenty of sleep. And then the last thing you said was stress reduction.

A: Managing stress. It turns out, we just published a study on meditation, a new trial on how does meditation affect your gene activity – your gene expression, as we call it. 

We did it with folks at Mount Sinai [Hospital] in New York. And what we found was that with a meditation practice, there are changes in your gene expression that work against inflammation and that actually create a healthier state. We also see changes in genes that affect the amount of amyloid in your brain during a full one-week intensive meditation course.

So we have meditation instructors, we have novice meditators who are learning, and our control group of people at the same resort who were just hanging out and having fun but not learning how to meditate. And there were significant differences in terms of very beneficial gene expression changes in those who were meditating.

Q: One of the biggest fears my patients have is that they might be developing dementia. So how do you distinguish between a ‘senior moment’ and dementia? I mean, people would kind of flippantly say, if you can’t find your car keys that’s one thing, if you find them and don’t know what they do, that’s another thing. But I always found that a very flip answer. What do you really say to a patient in that situation?

A: Well the fact is, as we get older, we don’t recall names as well, we can see the face of an actor we know but can’t recall the name as fast. There are changes that happen in the brain just as there are changes in the muscles. Our joints, our muscles get a bit weaker. So that’s why it’s so important to work out physically and mentally. You know, stay engaged in learning new things.

Q: Crossword puzzles? Learning a new language?

A: I like to say – if crossword puzzles help you, if it’s the New York Times it would help you between Friday and Sunday, because you’d probably have to look something up and learn something new. But it’s really learning new things. When you learn something new, you make new synapses – connections between nerve cells [in the brain]. And all learning is based on what you already knew, you learn by association to what you already knew. So not only do you make new synapses, but you strengthen the ones you already have.