It seems like every other day an article is published about the importance of the gut for optimal health. And for good reason. The gut truly is where everything begins and everything ends. It is the interface between the outside and inside of the body. (When something is in the digestive tract it is not really considered in the body until it enter the blood stream.)

There is a major paradigm shift happening which is changing the focus from how food affects us directly, to how food affects us through our microbiome (the bacteria in our gut).

In Brain Maker, Dr. David Perlmutter brings together the most recent research, showing us how our microbiome not only affects our gut health, but extends well beyond the borders into the brain, and entire body.

I’ve highlighted some of the key take-aways below:

The “Wandering” Nerve

We often think of the brain and central nervous system as the motherboard of the body, which directs activity all over. A one-directional super-computer that controls our bodily functions. However, early on in Brain Maker, Perlmutter makes it very clear that the communication is bidirectional; the brain can tell the gut what to do and the gut can likewise tell the brain what to do through our nervous system. It is a bidirectional roadway, and the road’s name is the Vagus nerve.

In fact, the gut makes about 90% of the serotonin in your body; a neurotransmitter that is strictly considered a “happy brain chemical” in the psychiatry world. This might help explain why the standard therapy for depression, selective serotonin inhibitors, are actually not better than a placebo.¹ It might also account for the fact that the most common side-effects from SSRIs are digestive-related symptoms.

To further the connection between the gut and mental health, Perlmutter discusses in depth how inflammation, which begins in the gut, can actually cause depression. He also mentions that this information is not new. It’s actually been around for 80 years, and he quotes a corresponding study.

[pullquote]It is far from our mind to conceive that all mental conditions have the same etiological factor, but we fell justified in recognizing the existence of cases of mental disorders which have as a basic etiological factor a toxic condition arising in the gastrointestinal tract.[/pullquote]

ADD Is Not A Ritalin Deficiency

One study that Perlmutter discusses shows some promising alternatives to the commonly prescribed Ritalin for attention deficit disorder (ADD) and attention deficit hyperactivity disorder (ADHD). It was done over ten years ago and compared the common drug Ritalin to probiotics (specifically lactobacillus acidophilus) and essential fatty acids. What they found was that the outcomes were the same for both drugs and supplements in the treatment of ADHD. The implications of this are profound in that many children do not require these risky drugs, but can simply take a couple of nutritional supplements instead.

The Bacteria Are Making Me Fat

The “calories-in-calories-out” model of body composition is outdated. We know that if you take ten people, feed them the same amount of calories they are expending, some will gain weight, some will lose weight, and some will not change at all. So there must be something else at work here.

It turns out that the bacteria in our gut, can actually play a role in how many calories are extracted from food. For example, the Firmucutes family of bacteria have an increased ability to break down carbohydrates, thus liberating more calories.

You can actually test for this in the stool, and I have done this with many clients. It is called the adiposity index, and it looks at the ratio of Firmicutes to Bacteroidetes. It can be quite illuminating to determine your adiposity index.

Another discovery related to body composition, points to the use of antibiotics. Dr. Martin Blaser has shown that when mice are given antibiotics they gain 15% more fat than their counterparts. What’s interesting is that factory farmers know about this effect and exploit it to stimulate growth in their livestock. In fact, 70% of the antibiotics produced are fed to livestock, not humans.

Conditional Residents

Ever since the first scientist saw a microbe under the microscope, we have waged a war against them. Turns out most of them are good, some can be bad, and even the really bad ones are not always bad.

For example, E. coli can cause some serious symptoms. But when it exists in the right number, it can produce an important nutrient, vitamin K.

H. Pylori has a similar story and has unfortunately been in the hot seat over the years. H. Pylori is the bacteria that was discovered to cause ulcers. As a result, when an individual gets an ulcer, diagnostics are performed to see if H. Pylori is present, and then antibiotics are prescribed. Turns out H. Pylori has some very important functions, like regulating appetite. You might also be surprised to learn that about 66% of people who have detectable levels of H. Pylori, never even get an ulcer.

The final example focuses on a potentially deadly bacteria, C. Difficile. You might be surprised to know that it is found in the intestines of 63 percent of newborns and 33 percent of toddlers. It lives synergistically with its host unless antibiotics come along and disrupt the gut environment. Essentially, the antibiotics wipe out the competition of C. Difficile, and the bacteria can then proliferate and become pathogenic.

Missing Microbes

Dr. Martin Blaser wrote a brilliant book called Missing Microbes. In his book he discusses how the diversity of people’s microbiomes is dwindling. The culprits? The overuse of C-sections, frequent antibiotic use, a hyper-sterile environment, and a suboptimal diet.  Perlmutter highlights this and then points out that C-sections also increase risk of allergies, ADHD, Autism, Celiac disease, obesity, and Type-1 Diabetes. The good news is that if you were born via c-section, there are still ways that you can ensure a healthy gut and microbiome (more on this below).

Gluten-free, Still Not A Fad Diet

People sometimes ask me, “do you think ‘gluten-free’ is just a fad diet?” And my answer usually includes many references to research on the topic, which show beyond a shadow of a doubt, gluten is not healthy for anyone.

One of gluten’s (more specifically gliadin’s) methods of causing damage, is to compromise the integrity of the small intestine lining, making it “leaky”. Once the lining has been breached, gluten can have direct effect on the nervous system, and pave the way for other chemicals (like lipopolysaccharides) to go systemic and cause damage.

The Bacterial Weapon

Remember, there are 100 trillion bacteria on us and in us. Well, most of them are in our gut, and are thus subject to a relatively harsh environment. They are constantly exposed to digestive juices, like bile acids released from the gallbladder. Thus, they have a protective feature called lipopolysaccahride (LPS) which gives them structural integrity, as well as protects them from digestive juices.

The reason I’m focusing on LPS, is that it is a well known endotoxin. When the gut is leaky, LPS has the ability to get into the blood stream and have a toxic effect on peripheral tissues. In fact, LPS is actually used in the lab to create inflammation.

Going Into Gut Rehab

In Brain Maker, after Perlmutter presents a mind-boggling amount of research, he ties it all together with a simple list of actionable things one can do to ensure optimal gut and brain health. Here is the list:

1. Consume probiotic-rich foods
2. Eat low-carb, high-fat diets
3. Enjoy wine, tea, coffee, and chocolate
4. Eat prebiotic-rich foods
5. Drink filtered water
6. Fast 4 times per year

I have only brushed the surface here. In Brain Maker, Perlmutter pulls you into a world of new possibilities. The emerging science presented, is translated into usable information for the reader whether you are a nutritionist, doctor, health care practitioner, or simply just looking for the latest and greatest in functional medicine. It truly is a revolutionary book.

– Josh

Note: All references from this article can be found in Brain Maker.

1. BMJ 331 (2005):155-157