Neurogenesis in Adults: 3 Powerful Ways to Upgrade Your Brain & Your Life.
A little while back, I was fortunate to have the opportunity to speak with Brant Cortwright on the topic of neurogenesis in adults.
Brant Cortright, Ph.D. and brain health coach, is the author of "The Neurogenesis Diet and Lifestyle: Upgrade Your Brain, Upgrade Your Life." He is a Professor of psychology at the California Institute of Integral Studies. He maintains a private practice as a licensed clinical psychologist in San Franscisco with a focus on depression, stress and anxiety, career and meaning, as well as relationship and intimacy issues.
He has authored two previous books, "Integral Psychology" and "Psychotherapy and Spirit" (both published by SUNY Press.) He speaks and gives workshops around the US, Europe and Asia.
Neurogenesis in Adults: How did it come to be studied?
Denise: Tell us about your background and how you came upon the research for your book, " The Neurogenesis Diet and Lifestyle: Upgrade Your Brain, Upgrade Your Life" and why you chose to write about it.
Brant: I was originally doing a book on holistic approaches to depression, so body, heart, mind, and spirit versus depression. As I was looking at antidepressants and SSRI's, I realized that the whole Serotonin deficiency theory around depression was a myth.
There have been many studies done looking at people's serotonin levels. These studies have found that most people have normal serotonin levels, whether they are depressed or not. A few studies even show that some depressed people have higher than normal levels, while others have lower than normal. But for the most part, it's been found that even depressed people have normal serotonin levels.
Digging further into the literature and research, I realized that the "serotonin deficiency" theory was really a myth that has been debunked probably 15 years ago.
Studies have shown that the beneficial effects of antidepressants come from the increase in the rate of neurogenesis that patients experience. SSRI's don't reduce depression by increasing the serotonin levels. They reduce depression by increasing the rate of neurogenesis. And, dopamine reuptake inhibitors work because increasing dopamine stimulates neurogenesis.
For example, in rats, they found that increasing serotonin levels but stopping the rate of neurogenesis, does not improve depression. But when the rate of neurogenesis increased, but the serotonin levels remain the same, the rats become un-depressed.
It's the rate of neurogenesis that matters.
Looking deeper into the literature regarding neurogenesis, it became clear that the real story is that low rates of neurogenesis are associated with depression, anxiety, stress, cognitive decline, and memory problems.
Conversely, high rates of neurogenesis are associated with the opposite such as, rapid learning, cognitive enhancement, robust emotional resilience and protection against stress, anxiety and depression.
For me, that's the real story.
There's a researcher named Fred Gage at the Salk Institute in San Diego. Using mice, he found that by increasing the rate of neurogenesis by five times, he was able to create 'super mice.' They learned faster. They were smarter. They figured things out faster. They were robustly emotionally resilient. (Fred Gage link - https://gage.salk.edu/)
He used different factors in order to increase the rate of neurogenesis: physical factors and emotional factors. Gage's mice were kept in what he called an "enriched environment" where they had interesting things to explore. They had a lot of running wheels where they could exercise. They had a rich diet. And, they had a lot of other friendly mice they could mate with. All of this helped to increase neurogenesis by five times, which is pretty amazing.
Neuorogenesis is the creation of new brain cells. Up until the late 1990's we thought that neurogenesis stopped in our early twenties. But since then many research studies have shown that it actually happens throughout our entire lifetime.
Denise: Can you comment on the study that came out last year where they took samples of brain tissue and then looked for new or young brain cells? In this study, they didn't find any young cells or young neurons.
Brant: There have been many studies like that before the 1990's. Finding new brain cells is a really hard thing to do, because within a few weeks they become integrated. They mature and then they become integrated into the existing circuitry. It's very difficult to find these newborn brains cells. Fred Gage, who I mentioned before with experiment with the super mice, was the first to really show that neurogenesis happens in humans. And it was through increasing the tools of neuroimaging. But it has to happen on autopsy. You can't really see it, in living human beings. And so, it's a very difficult thing to find.
Progress doesn't move in a perfectly straight upward line. It goes up and down when it tends towards progress. Oftentimes the believers in a certain paradigm don't change their minds even with new evidence.
So this study that came out maybe a year ago, wasn't able to find a new brain cells. But then there's a more recent study that came out after the one you mentioned that found a lot of new brain cells and actually more new brain cells in older seniors that they thought were occurring before. And this study critiqued the methodology of the study that you mentioned.
Denise: I would imagine that it also has to do with the people from whom you're taking samples. All people don't age equally. You see a wide spectrum of how people age cognitively, physically, emotionally, not everybody's the same.
Brant: Yes. This newer study I mentioned, came up with some pretty hard evidence to show again that neurogenesis remains even in seniors. It's slightly reduced. But even seniors make new brain cells.
Neurogenesis: Biomarker For Health
Denise: So why did you choose to write about neurogenesis? What prompted you to do that?
Brant: I thought it was a story that many people didn't know about. People know about neuroplasticity, right? Making new brain connections, or what's called synaptogenesis, is fairly widely known.
People didn't really know about neurogenesis. And more importantly, they didn't know about the rate of neurogenesis as being this very important biomarker for brain health, cognitive health, and emotional health as well.
It also seemed as if no one knew that rates can be increased, like in Fred Gauge's study. Again, he was able to increase neurogenesis by five times.
It's probably possible to increase rates even more than that because there are so many supplements and nutrients that have been shown to increase the rate of neurogenesis. Imagine what you could do when you mix them all together?
I don't think we really know what the upper limit of increasing your rate of neurogenesis is. So this whole focus on the neurogenic capacity of the brain to create new brain cells and increase neuroplasticity fascinates me.
What Things Slow Neurogenesis?
Denise: Can you talk about neurogenesis and your protocol as it relates to things like depression, anxiety, and brain fog?
Brant: I've worked with many people with anxiety and depression, and some with brain fog. There are different causes to each. But one thing they all have in common is the neurogenic capacity of the brain and how much neurogenesis is really occurring.
In these cases it's really important to get a good sense of what their diet is like. What is their emotional life like? What are the emotional stressors in their life? What kind of relationships do they have? What kind of spiritual practices do they make use of? It's important to do an overall assessment of the person.
Another thing that's become clear to me is that there are many neurotoxins in the environment that slow down neurogenesis and neuroplasticity. This results in mental health issues like anxiety and depression.
The rates of anxiety and depression are skyrocketing.
Childhood rates of depression are five to eight times now what they were in the 1960's. Childhood rates of anxiety are eight times what they were in the 1960's. And these numbers are not because we've got better diagnosis that we did the 1960's. We've got ADD, ADHD, and autism. We've got all these issues on the rise.
What's happening there? Part of the answers is the growing number of neurotoxins in the environment. It's a perfect storm of neurotoxins. So another key is to reduce exposure to neurotoxins, because neurotoxins lower the rate of neurogenesis. They slow it way down.
Many neurotoxins also produce inflammation; and inflammation slows neurogenesis to a crawl. Also, chronic inflammation can move into the brain. Just about everyone who has brain fog, has some degree of brain inflammation. Their low rate of neurogenesis and the inflammation prevents them from thinking clearly.
We're seeing more anxiety, more depression, and more rapid cognitive decline because of the neurotoxins in the environment.
For example, glyphosate, in roundup, is the most widely used pesticide in the world right now. Millions of pounds are sprayed into the environment every single year. It's been found in 93 percent of Americans. It's in just about everything you eat.
If you eat straight organic food, you will eliminate most of it; but again, not all of it. People who live in the midwest and the east coast drink it in their water. It's in the groundwater, the rain, the dust,... it's everywhere.
Glyphosate is in everything. It's in cotton balls. It's in tampons. It's because cotton is a genetically modified crop and so it can withstand high amounts of glyphosate. It takes a real effort to clean up your environment, your home environment, your eating habits.
Glyphosate is an antibiotic and it wipes out the microbiome. It also stimulates zonulin. Zonulin opens up the tight junctions in the intestines. The tight junctions are what keep out the bad stuff, but let in the good stuff. When you consume glyphosate, it opens up the tight junctions, causing leaky gut. The body then gets bombarded with toxins, which produce inflammation.
Now the tight junctions of the gut and the intestines are very similar and operate along the same chemical pathways as the tight junctions of the blood brain barrier. When the blood brain barrier opens up toxins flood into the brain. This is a huge thing, which hardly anyone knows about. These toxins slow down neurogenesis. They produce a sense of anxiety. People know something is wrong, but they don't know what it is. These sensations are not psychological, they're physical.
Another pervasive toxin that we consume is mercury. Let's take fish for example. Things like Alaskan wild salmon or anchovies tend to be better than eating tuna. Tuna is not a great idea for most people because there's so much mercury in it. Mercury is the most powerful neurotoxin known to human beings, second only to plutonium.
All it takes is a few molecules of mercury to curdle neurons. It's unbelievable what a potent neurotoxin mercury is. We get mercury from fish. We get from breathing smog in coal burning parts of the country.
Smog is, is a major problem for the brain, particularly the small particles in smog. For instance, particles that are 2.5 micrometers go from your lungs get into your bloodstream and then pass through the blood brain barrier and into your brain. These particles just sort of smash into neurons and create inflammation all over the place.
There are some researchers who think that 30 percent of Alzheimer's is due to smog. In an attempt to repair that damage, the body produces amyloid plaque. And amyloid plaque is part of what's involved in Alzheimer's. They've begun to find amyloid plaque now in 11 month-old babies who live in areas with intense amounts of smog. They didn't think it was possible to find amyloid plaque in babies. It's mind-blowing.
We live in a of perfect storm of neurotoxins that nobody really knew about until now. Nobody knew. We stumbled into this innocently. Nobody knew that there's all this damaging material there, but at the same time, now we know what to do about it.
So with my patients, number one that changing their diet to be more neurogenic... organic and away from pesticides, gets rid of many of the neurotoxins. And this starts to clear up the symptoms they may be experiencing.
Another thing is, eliminating sugar in the diet. Sugar will reduce your rate of neurogenesis. Eating a low carbohydrate, high fat diet is really helpful. Bad fats are not so great because bad fats and sugar produce inflammation, which as we've discussed, turns down the rate of neurogenesis.
Denise: I was going to ask why should people in their twenties, thirties, or even into their forties and feel like they're healthy, care? Neurogenesis isn't necessarily high on their list of things to think about unless they're experiencing brain fog or they're interested in brain optimizing.
But as I'm listening to you talk about this, and even as I was reading your book, I realized that no matter how young you are, you need to be on this. This is a self-defensive lifestyle in an assaulting world no matter where you live, because it is everywhere.
Brant: Yeah, exactly right. Exactly right. Alzheimer's begins decades before you see symptoms. As I mentioned, you begin to see the amyloid plaque early, in the thirties and forties. But the symptoms show up decades later. It's an epidemic.
Right now one in three 85 year olds has Alzheimer's. If present trend-lines continue, it will be one in two 85 year olds will have Alzheimer's. And most people expect to live to be 85. So you've got a 50 percent chance of developing Alzheimer's. That's why now's the time to start taking care of your brain. That's absolutely right.
Denise: How much impact can someone have on their own mental and physical health? Do you find that people can turn these things around for themselves? Can they stop the progress or reverse the progress of their issues?
Brant: That's a great question because that can happen. Definitely. But it depends on how far it's gone.
Some really far-gone Alzheimer's patients may see an improvement. But less than if you're beginning to experience cognitive decline.
This sort of normal age related cognitive decline, it may be statistically normal, but it's not necessarily healthy normal. Because we live in this neurotoxic environment, it's statistically normal, but it's not normal. It's not really what we want to see as normal.
It's important to make sure you're eating well, sleeping well, getting exercise, having good, supportive, loving relationships, and reducing stress. Sleep is hugely important because this amyloid plaque builds up during the day and then during sleep, the brain clears it out through the glymphatic system. And if you don't sleep well, your body doesn't clear out the amyloid plaque. So sleeping a good seven or eight hours is turning out to be one of the major interventions in reversing or preventing Alzheimer's and cognitive decline.
Fasting for Neurogenesis
Denise: Part of neurogenesis is also autophagy. Can you talk a little bit about how neurogenesis isn't just making new brain cells, but is also cleaning up old cells.
Brant: One thing that stimulates neurogenesis is mild stress, like fasting.
Fasting also clears senescent cells (autophagy) and cells that aren't working well that produce inflammation. Intermittent fasting is a fabulous way to increase neurogenesis. The figures I'm hearing recommend a sweet spot of 16 hours without eating with an eight hour eating window. After 16 hours the rate of autophagy doesn't increase that much.
So if you can get it up to 16 hours or 17 hours or a five day fast, you'll clear senescent cells throughout your whole body and in your brain, as well as stimulating neurogenesis.
How Tech May Slow Neurogenesis
Denise: I'm a parent and I know other moms, we often bemoan technology its seemingly mind numbing impact on our kids. Can you comment on any of the effects of those sorts of tools, video games, cell phones, and how they effect or don't affect neurogenesis?
Brant: I don't know to what extent it's actually being tested, but we do know certain things. We do know that the EMF from cell phones produce a lot of inflammation in the testes and in the mitochondria of neurons.
For example, there has been a 50% drop in male sperm counts in the past couple of decades, which is being tied into exposure to EMF from laptops and cell phones.
Brant Cortright's must read book for all those interested in neurogenesis. How to get a stronger and healthier mind that serves you through all the ages.
But also we're finding that a lot of brain fog is also connected to the inflammation that occurs from the EMF when the cell phone is used right up against the head. It's best whenever you carry a cell phone to have it on airplane mode, unless you're expecting a call. It's best to use the speaker rather than put it up to your head.
And the other thing is that it cannot substitute for real relationships. Online relationships are not the same as interpersonal relationships. We've noticed emotional fragility when actual in person relationships are substituted with online relationships.
My kids are grown up now. But when they were younger, I tried to limit their computer use. They didn't get cell phones until later.
It's interesting because a lot of the silicon valley people don't let their kids play with their Ipads during the week. They limit cellphones for their kids
I think there's both a physical dimension in terms of the EMF's and the psychological impact in terms of lack of real contact, that are potentially really destructive facets of these technologies. . This is dangerous technology. It's wonderful in many ways, but it's clearly has to be limited.
The Gut Brain Connection & Neurogenesis
Denise: Can you talk about, the gut brain access and neurogenesis in that context? Apparently, it's one big system.
Brant: It looks like there are at least a few strains of probiotics that seem to increase the rate of neurogenesis. And in the book, I mention three different strains of probiotics the increase BDNF (brain-derived neurotrophic factor) and which also have an influence in reducing anxiety and depression: lactobacillus helveticus, lactobacillus rhamnosus and bifidobacterium Longum.
There have been some amazing studies showing that those strains seem to be helpful with mood disorders, anxiety and depression. They also appear to increase BDNF and some other markers of neuro growth factors.
It would seem like they probably increase neurogenesis as well, but we don't know that for sure.
Most indigenous peoples have 20 to 30 thousand different strains of bacteria living in their intestines. Most Americans only 5,0000-10,000, which is not a good ecosystem: the less diversity, the less robust the ecosystem.
So the goal is to not only have particular strains, but increase the variety of strains as well.
L. plantarum has been found to increase the diversity of strains.
There's a product called restore on the market, which helps repopulate the gut as well as seal the tight junctions.
The Easiest Way to Increase Neurogenesis
Denise: There are a lot of different things that you prescribe in your book for people to do. It can seem overwhelming. So if you had to give people the couple of big ticket things to get them started what would those two or three or even one thing be?
Brant: The single most important thing you can do for the of your brain is taking omega 3 fatty acids. Omega 3's consist of ALA (alpha-linolenic acid), EPA (eicosapentaenoic acid), and DHA (docosahexaenoic acid). DHA is the fundamental building block of the brain, right? Sixty percent of the brain is fat. And about a third to half of that fat is DHA.
So it is the fundamental building block of the brain.
EPA is also important as an anti-inflammatory. DHA is anti-inflammatory, but EPA is stronger and works on different pathways.
I like to see a 50 /50 EPA/DHA balance from a molecularly distilled form of Omega 3. Most people should do probably four to six grams a day.
The RDA says three grams a day, but the RDA is low.
I've been doing six grams a day for years. I think this is probably the single most important thing anybody can do for the brain.
Another thing would be curcumin. It's very neurogenic and anti-inflammatory. It's also an antioxidant. Curcumin has also been shown to act as an anti-depressant. The only issue is that it's not very bioavailable.
Green tea extract is great. And then of course, blueberries are really powerful.
When it's a challenge to eat fresh or frozen berries, we'll sometimes take this extract.
An economical green tea extract that I take.
A clean & easy Omega 3 that we take.
Denise: Your approach is holistic, encompassing emotional, spiritual, and dietary recommendations. To reiterate, why would someone care to take an all-encompassing approach versus taking an antidepressant or an anti-anxiety pill. What difference does that make over the long-term?
Brant: Well, taking a holistic approach is what really heals the brain and brings it up to a higher state of functioning. An anti-depressant or anti-anxiety agent simply mask the symptoms. They don't really heal the brain.
And in terms of antidepressants, continuing to take them causes the brain to down-regulate its own production of serotonin. Anxiety agents and tranquilizers down regulate the production of Gaba. These effects make it very difficult to come off of these drugs for a lot people.
We want our brains to be doing what the medication is doing naturally and spontaneously. One thing that Fred Gauge's research showed is that intervening on one level has a partial effect, but if you intervene on all these levels, it has a synergistic effect much more powerful than any one thing alone.
Denise: One final question, going back to Omega 3 that I heard on one of your interviews is that flax oil doesn't work as a source of Omega 3s. You can really only get what you need from fish oil or algae oil. Can you explain?
Brant: The body converts ALA to EPA and DHA, but at the very inefficient rate. I think it's something like three to five percent in an 18 year old, and it goes down from there as we age. They've done studies where they've tried to increase the blood levels of DHA and EPA through flax oil and they've not been successful. If you want to do vegetarian, you'll need to do the algae oil.
Brant Cortright's must read book for all those interested in neurogenesis. How to get a stronger and healthier mind that serves you through all the ages.
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