Second Brain: Digging Deep into Alzheimer’s

Pratibha Pansari
4 min readDec 13, 2020


In every part of the world, people are living longer than they used to. We are thankful to the scientific advancements that it’s no longer unusual for a person who lives in the 80s and beyond. Despite boosting a longer lifespan we are not healthy today.

This fact — that people are living longer than ever before — should always be a wonderful thing. But what happens when it’s not? Among all the disorders that plague us late in life, one stands out as a particularly big threat to society: Alzheimer’s disease.

Alzheimer’s disease is an irreversible, progressive brain disorder that slowly destroys memory and thinking skills and, eventually, the ability to carry out the simplest tasks. It is a progressive form of dementia. Dementia is a broader term for conditions that negatively affect memory, thinking, and behavior. These changes interfere with daily living.

It’s a terrible disease that devastates both those who have it and their loved ones. We all understand how awful it is to watch people you love struggle as the disease robs them of their mental capacity, and there is nothing we can do about it. It feels a lot like you’re experiencing a gradual death of the person that you knew.

Although treatment can help manage symptoms in some people, currently there is no cure for this devastating disease.

We are less healthy today than our ancestors, despite boasting a longer lifespan. This fact hit badly to me and allows me to dig out deep to find answers where we can dramatically improve human life.

My curious and philosophical mindset introduced me to the Second Brain. Yes, we do have a second brain that influences our judgment, and much else besides. Known as the Enteric Nervous System (ENS) — enteric meaning ‘to do with intestines’ — it’s an extensive network of brain-like neurons and neurotransmitters wrapped in and around our gut.

Most of the time, we’re unaware of its existence, as its prime function is what one would expect: managing digestion. Yet the presence of all that brain-like complexity is no coincidence.

Second Brain for Alzheimer’s?

So is this time to use your second brain? It’s a tough call, as there are very few hard facts to go on.

The first hints of the second brain’s importance emerged over a century ago when researchers find that our gene needs traditional food and for the same reason our ancestors were healthy than us. It began making some strange discoveries about our digestive system.

The key feature of Alzheimer’s disease is the deposition of amyloid-beta (Aβ) followed by the formation of plaques and neurofibrillary tangles composed of hyperphosphorylated tau protein. Those deposits trigger neuroinflammation leading to synapse loss and neuronal death. It is still not well-known what triggers amyloid plaque formation, but the gut microbiota plays certainly an important role in the process. Regarding tau, it is a highly soluble protein modulating the stability of axonal microtubules. According to the tau hypothesis, altered and aggregated forms of this protein appear to act as toxic stimuli contributing to neurodegeneration.

The ENS is the intrinsic nervous system of the gastrointestinal tract. Its neurons are organized in microcircuits allowing for modulation of gastrointestinal function independently of the CNS, although the systems are interconnected and influence one another. This connection also allows the disease to spread.

The regular APP expression in the ENS supports the theory of ENS involvement in AD. The APP transgenic mice develop accumulation of Aβ in the enteric neurons leading to a decrease in enteric neuron abundance, dysmotility, and increased vulnerability to inflammation. Preliminary data confirm that changes in the ENS in APP overexpressing transgenic mice correlate with the disease expression.

The influence of gut microbiota on brain function is being constantly investigated, and the mechanisms of the brain-gut-microbiota axis contribution to the pathogenesis of stress-related conditions or brain disorders are being discovered. In irritable bowel syndrome, where altered microbiota is one of the key pathophysiological factors of the disease, some preliminary results indicate that there is also an increased risk for either AD or non-AD dementia development. Other conditions, where the gut microbiota influence has been implicated, include autism, schizophrenia, or multiple sclerosis.

It’s no wonder our current drugs that target single chemical processes have lackluster results.

I have dedicated a great amount of time to read the greatest works of scientists and philosophers, just to find out the answer of some unanswered questions.

ENS and the brain-gut connection came as a catalyst in my life and shocked me to my core and I finally realized what we should be doing as a researcher. And this is why I’m convinced that a “functional medicine” approach that appreciates the importance of metabolomics, gene technology, and pharmacotherapy with the wisdom of ancient medicine principles, is the only way to at least attempt to prevent and reverse dementia.

Functional medicine and the brain-gut connection look set to become a major focus for 21st-Century medicine.

Suggested read and Reference:

· The second brain {Book by Michael D. Gershon}

· Deep Nutrition: Why Your Genes Need Traditional Food {Book by Catherine Shanahan, M.D}

· Alzheimer’s Disease

· The bowel and beyond: the enteric nervous system in neurological disorders