By Dr. Mercola
The quality, quantity, and composition of the bacteria in your gut have enormous influence on your brain. Dr. David Perlmutter explores this phenomenon in great detail in his new book, Brain Maker: The Power of Gut Microbes to Heal and Protect Your Brain-for Life.
Dr. Perlmutter is a board-certified neurologist and a fellow of the American College of Nutrition (ACN). He also has a clinic in Naples, Florida, and he's been very active in publishing his findings in peer-reviewed medical journals.
His previous book, Grain Brain, topped the New York Times bestseller list for 54 weeks. In my view, Dr. Perlmutter is probably the leading natural medicine neurologist in the US.
Certainly, most neurologists fail to consider how lifestyle impacts the neurological disorders they diagnose and treat every day, and prevention is an area of utmost importance as we still do not have effective treatments for many of the most common brain disorders.
"We're now recognizing from research at our most well-respected institutions from around the globe that the gut bacteria are wielding this very powerful sword of Damocles," he says.
They determine whether we're going to have a healthy brain or not, whether our brain is going to function well or not, and whether our brain is going to become diseased or not. Who knew that we'd be referring back to the gut?"
Microbiome Research Shreds Notion of Reductionism
It turns out that this notion of reductionism—where your body is reduced to its individual parts—is completely nonsensical and grossly flawed. As explained by Dr. Perlmutter, every system in your body interrelates in a way that ultimately causes the manifestation of either health or disease.
In a previous interview, Dr. Perlmutter discussed specific dietary factors that influence your brain health, but one of the primary mechanisms of action that explains how a healthy diet "works" is that it upregulates, modifies, and improves the quality of your gut microbiome.
"These hundred trillion bacteria that live within your gut are so intimately involved in your brain at a number of levels. They manufacture neurochemicals, for example. Things like dopamine and serotonin.
They manufacture important vitamins that are important to keep your brain healthy. They also maintain the integrity of the lining of your gut," he explains.
The latter is important because when your gut lining becomes compromised, you end up with permeability or leakiness of the gut. This increases inflammation, which is a cornerstone of virtually all brain disorders, from Alzheimer's and multiple sclerosis (MS), to Parkinson's and autism.
"We've got to really deal with it on a preventive basis," Dr. Perlmutter says. "[We must] understand what in our Western culture, especially from a dietary perspective, is threatening the health of our commensals.
We call these bacteria 'commensals' because they share the table with us. We eat together with the bacteria. Basically, they eat what we eat. Our food choices have a dramatic effect on the health viability and even the diversity of those gut bacteria."
Research Shows Swapping Gut Bacteria Can Reverse Type 2 Diabetes and Other Diseases
A researcher in Amsterdam, Dr. Max Nieuwdorp, has published a number of studies looking at changes in the microbiome that are characteristic of type 2 diabetes.
In one trial, he was able to reverse type 2 diabetes in all of the 250 study participants by doing fecal transplantations on them. Remarkable as it may sound, by changing the makeup of the gut bacteria, the diabetes was resolved.
Dr. Perlmutter has embraced this new information full force, and has even helped develop a peer-reviewed scientific journal, Medicus, that focuses on this kind of research. They're also holding an annual conference to which the leading microbiome researchers in the world are invited.
In his view, and in mine, the understanding and practical adjustment and modification of the microbiome is an important part of the future of medicine. Fifteen years ago, we thought that the Human Genome Project (HGP) would allow modern medicine to leapfrog into new gene-based therapies that would solve all our ills.
That didn't happen, as HGP discovered that genetics are only responsible for only about 10 percent of human disease,1 the rest—90 percent—are induced by environmental factors. Now we're coming to realize that your microbiome is actually a driver of genetic expression, turning genes on and off depending on which microbes are present.
"The gut microbiome is 99 percent of the DNA in your body, and it is highly responsive and changeable based upon lifestyle choices, most importantly our food choices," Dr. Perlmutter says.
"There's this beautiful dance that happens between the gut bacteria and your own DNA. The gut bacteria actually influenced the expression of our 23,000 genes. Think about that. The bugs that live within us are changing our genome expression moment to moment.
Our genome has not changed over thousands of years. But now, suddenly, because we're changing our gut bacteria, we are changing the signals that are going to our own DNA; coding now for increasing things like free radicals, oxidative stress, and inflammation. That is a powerful player in terms of so many disease processes...
Being a brain specialist dealing with brain disorders, my whole career I've been stymied by not having really powerful tools to implement to bring about changes in individuals who have these issues. Now we're beginning to get those tools, and they are in the gut. Who knew?
In neurology school, we didn't study the makeup of the gut bacteria and how that would ever influence the brain, and yet, this is leading-edge science.
This is what our most well-respected researchers and peer-reviewed journals are talking about: not only are the gut bacteria fundamentally involved in brain health, but you can change the gut bacteria by interventions – taking probiotics and choosing to eat foods that are rich in prebiotics and to enhance the growth of good bacteria – and even more aggressive therapies [such as fecal transplants]"
Nourish Your Microbiome, and It Will Nourish You
Two key strategies to nourish and protect your microbiome are to limit your consumption of antibiotics to when they're absolutely necessary, and be judicious in terms of the foods you eat. Ideally, opt for whole, raw organic, non-genetically modified (GM) foods, along with traditionally fermented and cultured foods. Good examples include fermented vegetables of all kinds, including sauerkraut and kimchi, kombucha (a fermented drink), and fiber-rich prebiotic foods like jicama (Mexican yam), Jerusalem artichoke, garlic, and dandelion greens.
Avoiding confined animal feeding operation (CAFO) meats is also important, as the animals raised in these factory farms are raised on antibiotics, which changes their microbiome as well. This routine practice also promotes antibiotic-resistant bacteria that now threaten the lives of tens of thousands of Americans each year. Pesticides have also been shown to alter gut bacteria and foster drug-resist bacteria in the soil and food, so organically-grown and raised foods are really your best bet.
"These are all very relevant lifestyle choices that we can make to enhance the health and the diversity of the gut bacteria. That's going to give us a lifelong advantage in terms of being resistant to the very diseases that we dread the most," Dr. Perlmutter says.
"The true definition of symbiosis: we're supporting their health and they are supporting our health. We do that by the foods that we eat. They are, as I said, commensals. We're sharing this meal. We treat them right by eating fermented foods that are rich in probiotic bacteria and prebiotic foods that contain prebiotic types of fiber like inulin and fructooligosaccharides (FOS).
These are nutrients that enhance the growth of good bacteria with multitudes of studies indicating things like weight loss, a better control of blood sugar, and reduction of inflammation... One study came out just last month showing how children with allergic rhinitis and breathing issues have improvements by just giving them fiber to enhance the growth of healthy bacteria."
The Link Between the Microbiome and Autoimmune Disease
Inflammation is a hallmark of autoimmune diseases such as MS, Lou Gehrig's disease, Crohn's, and inflammatory bowel disease, just to name a few. As explained by Dr. Perlmutter, many of the factors that affect permeability of the blood-brain barrier are similar to those that affect the gut, which is why leaky gut can lead to neurological diseases as easily as it can manifest as some other form of autoimmune disorder.
The permeability of your gut lining can be measured by looking at a chemical called lipopolysaccharide (LPS), which is the covering over certain groups of bacteria in your gut. When you have higher levels of antibodies against LPS in the bloodstream, it's a marker of leaky gut.
LPS is also in and of itself a powerful instigator of the inflammatory cascade. Higher levels of LPS in the blood dramatically increase inflammation throughout your body, including your brain. Alzheimer's and Lou Gehrig's disease, for example, are both correlated with dramatically elevated levels of LPS.
"In Brain Maker I present pretty aggressive treatments for maintaining and restoring gut health using a variety of techniques – from using probiotic enemas to even going as far as having people get fecal transplantation. And do we see success? We sure do," Dr. Perlmutter says.
"I have a case history in Brain Maker of a young man with MS who couldn't walk without two canes and who underwent a series of fecal transplantations in Europe, and came back and walks without any assistance whatsoever. His videotape is linked to the book and is on our site. I use the video of this man walking when I do lectures to physicians. They look at this with their jaws hanging, because again, for you and me, this was never even a consideration in medical school...
If you did pay any attention to the gut you'd become a gastroenterologist, otherwise there'd be no interest in looking at it. But it turns out that it's relevant whether you're a gastroenterologist, a neurologist, a psychiatrist, a joint specialist, a skin specialist, or even a cancer specialist. We've got to pay attention to nurturing these bacteria if we're going to keep people healthy."
Seven Essential Keys to Rehabilitate Your Gut, from Birth to Death
In his book, Dr. Perlmutter delves into seven essential keys for rehabilitating your gut, starting at birth.
1. Vaginal birth
Do everything you can to avoid a Caesarian section. When you elect to deliver a child via Caesarian section – and there are times when it needs to be done to save the life of the mother or the baby—understand that by and large, you're tripling the risk for attention-deficit hyperactivity disorder (ADHD) and doubling the risk for autism in your child. You're also dramatically increasing the risk that your child will struggle with obesity, type 1 diabetes, and allergies. These are all inflammatory issues that are dramatically increased in children born via Caesarian section.
Dr. Perlmutter describes a simple and elegant technique developed by researchers at Yale University, whereby an organic gauze sponge is placed in the birth canal before the mother who is going to have a C-section is given the IV antibiotics. The sponge is then removed, the antibiotics are given, and as soon as the baby is born, the sponge is placed over the baby's face, inoculating the child with its mother's bacteria. This could be a good adjunct anytime a Caesarian is required. Unfortunately, at present it's unlikely you'd be able to get your doctor to do it.
Aside from providing the most appropriate nutrients, breast feeding also affects your child's microbiome via bacterial transfer from skin contact.
When you change your microbiome, certain groups of bacteria tend to be favored, such as the Firmicutes group. When present in excess, Firmicutes increase your risk of obesity. Animal research shows that when you change the animals' microbiome using antibiotics, they gain weight. We also give antibiotics to cattle to make them fatter, faster. The same thing occurs in your body, which is why avoiding unnecessary antibiotics is so important.
Disinfectant products like antibacterial soaps and hand gels also fall into this category and should be avoided as much as possible.
4. Refined sugar and processed fructose
Sugar and high-fructose corn syrup (HFCS) preferentially increases the growth of pathogenic disease-causing bacteria, fungi, and yeast, so limiting the amount of refined and processed sugars in your diet is a key dietary principle for gut health.
According to Dr. Perlmutter, fructose in particular promotes gut dysbiosis, and there's also a good correlation between fructose consumption and the levels of LPS, the inflammatory marker that shows your gut is leaking.
Fructose is also far more aggressive in terms of causing glycation of protein than other sugars, meaning high levels of sugar in your blood that bind to proteins. This too is correlated with leaky gut, and may explain why fructose consumption is related to increased gut permeability, and inflammatory diseases like obesity.
5. Genetically engineered foods and pesticides
Avoid genetically engineered foods. As noted by Dr. Perlmutter: "Yes, there is a clear and present danger in the notion of genetically modifying the food that we share with our gut bacteria. The gut bacteria are expecting the type of food that they have been provided for a couple of million years.
Suddenly, we're introducing foods that are genetically unlike anything the human microbiome has ever seen. The research that allows the Food and Drug Administration (FDA) to allow genetically modified food has not even considered looking at the effects of GMOs on the human microbiome."
Glyphosate, which is liberally used on genetically engineered Roundup Ready crops, and many non-organic non-GMO crops as well, has also been found to alter the human microbiome, so genetically engineered foods deliver a double assault on your gut bacteria every time you eat it.
"We're poisoning the food that we eat. If that's not bad enough, that's the food we're feeding our microbiome, which are going to determine whether we live or die," Dr. Perlmutter says. "It's a bit of a worry."
6. Probiotic foods
Focus on eating probiotic foods, such as fermented vegetables, sauerkraut, kimchi, kefir, and kombucha (a fermented drink). A broad-spectrum probiotic supplements may also be advisable—especially if you have to take a course of antibiotics.
7. Prebiotic fiber
Consume plenty of prebiotic fiber. Not all fibers are prebiotic, so not any old fiber will do the job here. Whole foods are the best. Examples include dandelion greens, which can be lightly sautéd, Mexican yam or jicama that can be chopped up raw and put in your salad.
Onions and leeks are also excellent choices. These kinds of foods will allow your gut bacteria to flourish, which is the key to health, disease resistance, and longevity.
Optimal Health and Disease Prevention Begins in Your Gut
By making new choices, following the recommendations outlined above—which are not excessively complex by any means—you can rehabilitate your gut bacteria so that they will do "the heavy lifting" of preventing disease and promoting the healthy function of your body and mind.
To learn more, I highly recommend picking up a copy of Dr. Perlmutter's NY Times bestselling book, Brain Maker: The Power of Gut Microbes to Heal and Protect Your Brain-for Life. In it you will also find plenty of references from well-respected medical journals that you can use to make more empowered choices.
Ultimately, it's a magnificent handbook on how to take control of your health and prevent and/or treat many diseases that are considered "incurable" from the conventional point of view, including Alzheimer's disease and MS.