Life Extension Magazine®
Contrary to previous scientific belief, human adult brain cells can regenerate. This discovery prompted Brant Cortright, PhD, professor of psychology at San Francisco’s California Institute of Integral Studies, to look at the research and write a book about this exciting new field of neurogenesis.
The Neurogenesis Diet & Lifestyle combines a holistic approach to increase the creation of new brain cells with the latest neuroscience research on enhancing brain health and cognitive function.
In his book, Cortright points to research showing that neurogenesis is “the most important biomarker for brain health most people never heard of.” While a low rate of neurogenesis is linked with mental disorders such as anxiety, depression, stress, and cognitive deficits, a high rate of neurogenesis has only positive effects—lowered stress, anxiety and depression, plus enhanced cognitive abilities including faster learning and better problem-solving skills.
Dr. Cortright sat down with us to discuss neurogenesis as well as some of the methods that can be used to enhance this extremely beneficial process.
LE: Medical science once believed that people stop growing new brain cells early in life, but recent research has shown that to be false. What are the implications of this?
BC: The discovery that your brain produces new brain cells as long as you are alive upends the belief that the brain stops growing in young adulthood. It also changes our entire picture of aging, for if new brain cells are being formed, then the brain can renew itself. What is key is the rate at which new brain cells form.
There are vast differences in how quickly people produce new brain cells, and your rate of neurogenesis may be the single most important factor for a high quality of life. When neurogenesis is high, you are alive, engaged, expansive, fulfilling your potential. Your mind’s abilities are enhanced and your emotional vitality is strong. You are protected from stress and depression. You feel good and life is fulfilling. Immunity is robust. Your spirits are high and your outlook is positive.
LE: What happens with a low rate of neurogenesis?
BC: Your brain shrinks, your life contracts, and you move toward memory loss, cognitive deficits, dementia, stress and anxiety, depression, reduced executive function and immunity, and myriad health problems. When neurogenesis is low, your whole quality of life suffers. Having a high level of neurogenesis may be the most important thing you can do to cultivate a high quality of life.
LE: In your book, you advocate a holistic approach to neurogenesis involving diet and stimulation of what you call the four levels of the brain: body, heart, mind, and spirit. What’s the rationale behind this approach?
BC: Different kinds of brain stimulation support each other. For instance, running boosts neurogenesis, but with running alone there is a 40% to 60% loss of these newly created brain cells. However, other parts of an enriched environment prevent neuronal cell loss but don’t increase the number of new neurons formed. Put together, there is a large boost in new brain cells as well as an almost 100% survival rate. But only a holistic, multipronged approach produces the powerful boost in both new neurons and survival rates that results in a major increase in neurogenesis.
LE: You recommend a number of foods and nutrients that are available as extracts.
BC: Yes. This makes including these in your diet more economical and practical. For example, a daily diet that includes fresh blueberries can be pricey, but two capsules of blueberry extract is much more affordable and easier to keep in the house.
LE: Which nutrients have been shown to increase neurogenesis?
BC: The four most outstanding foods for stimulating neurogenesis are blueberries, omega-3 fatty acids, green tea, and curcumin. It’s worth considering making these a part of your regular diet.
LE: Let’s take a closer look at some of these nutrients. What can you tell us about blueberries, for instance?
BC: It’s hard to sing blueberries’ praises highly enough. They act in so many ways to promote neurogenesis and protect the brain from cognitive decline that if blueberries were a drug, pharmaceutical companies would be bombarding us with ads to entice us to upgrade our brains with this “miracle drug.”
Numerous studies show adding blueberries to the daily diet of mice increases neurogenesis significantly. Further, blueberries seem to protect against cognitive decline, inflammation, oxidation (free radical damage), radiation, and glycation. Generally, it takes different substances to protect against any one of these things. That blueberries have so many effects is little short of astounding.
Blueberries are packed with polyphenols, especially flavonoids called anthocyanins that stimulate neurogenesis. More specifically, the anthocyanin dye, which causes the dark blue color, crosses the blood-brain-barrier to stimulate neurogenesis.
Blueberries have been shown to reverse cognitive decline in both humans and animals. Mice bred to develop Alzheimer’s showed improvements in memory when fed blueberries, and two neuroprotective chemicals were higher in these mice. Humans with cognitive decline showed improvements after consuming blueberries daily. Aside from increasing neurogenesis, blueberries allow better communication among neurons, something called signal transduction, and they also protect against brain injury, stroke, certain neurotoxins, excitotoxicity, and so may help with Parkinson’s, MS, and other neurodegenerative diseases as well.
LE: How about omega-3s?
BC: Neuroscience researcher Sandrine Thuret, PhD, of London’s Kings College, reported a 40% increase in neurogenesis by adding omega-3s in Science Daily in 2007. Other studies have shown equally impressive gains in neurogenesis.
Our brains are made up of about 60% fat. DHA, one of the most important of the omega-3s, constitutes about 30% of the brain’s cerebral cortex. In the ongoing tearing down, replacing, and rebuilding of our brains’ cellular structures, we want to consume high-quality fats in order to continuously rebuild our brains with the best fats possible. Omega-3s are the highest quality fats for brain development. A diet high in unhealthy or “bad” fats slows down neurogenesis, but a diet high in healthy or “good” omega-3s increases neurogenesis to a higher level.
LE: Green tea contains polyphenols, including epigallocatechin gallate (EGCG). Does this have an effect on neurogenesis?
BC: Yes. Green tea’s polyphenols have been shown to increase BDNF (brain-derived neurotrophic factor, which appears to be the main signal that turns on neurogenesis), and to have strong health benefits ranging from cancer prevention, cardiovascular benefits, immunity improvement, and glucose reduction. EGCG and green tea’s other polyphenols not only increase neurogenesis but, like blueberries and omega-3s, exert powerful antioxidant and anti-inflammatory effects as well. Green tea has clear cognitive benefits and even improves working memory, which is one of the most difficult functions to increase.
LE: How about the benefits of curcumin?
BC: Curcumin has strong neurogenic effects. In addition, it is a powerful anti-inflammatory and antioxidant compound. Aging populations who consume curcumin show better cognitive performance. It reduces beta-amyloid and plaque formation in aging humans and has high potential as part of an anti-Alzheimer’s strategy. It has long shown antidepressant effects, which naturally follow from decreasing inflammation and increasing neurogenesis.
LE: As just one other example, you also write about melatonin’s healthful properties.
BC: Melatonin is a hormone secreted by the pineal gland. The body secretes melatonin at night, when it’s dark and we’re asleep. Levels drop as we age, as does neurogenesis, and, accordingly, sleep disturbances increase. Melatonin increases neurogenesis and helps regulate it. It also increases the immune system’s capacity and has anticancer effects. Melatonin can be used as a sleep aid at night. There is wide dosage individual variation—some people take 1 mg per night while others take 20 to 30 mg per night. This is a vivid example of how you need to individualize your own approach to brain health.
LE: Finally, could you briefly outline how exercise of the mind relates to neurogenesis?
BC: Exercising the mind by engaging in various forms of mental stimulation increases neurogenesis and keeps mental faculties sharp. There is no quick fix for keeping our mental abilities strong, no one exercise or video game that will prevent the mind from deteriorating. Most forms of mental stimulation are discrete and do not generalize to other parts of cognitive function. Hence, we need to use our minds in as many ways as we can—reading, problem solving, remembering, discussing, writing, musical training, and attention training.
Building cognitive reserve by using our minds throughout our lives is an insurance policy against Alzheimer’s and dementia. At whatever age we begin, mental exercise increases neurogenesis and expands our world.
If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.
To order a copy of The Neurogenesis Diet & Lifestyle, call 1-800-544-4440.