The Charger Blog

Nutrition Sciences Major Discusses Brain Health and its Impact on the Gut

Beatrice Glaviano Ӱԭ26 explains the importance of proper nutrition to fostering a healthy gut microbiome, as well as why that is so critical to maintaining a healthy brain.

May 7, 2024

By Beatrice Glaviano Ӱԭ26

Courtesy of iStock.
Courtesy of iStock..

Hello, hello, everyone, and welcome to another edition of the Charger Blog. Today, IӰԭve finally found some time to actually write, and IӰԭm doing it at one of my favorite places of all time: . For those who are unfamiliar, ClaireӰԭs is a vegan-vegetarian eatery in New Haven that has kind staffing and a Lithuanian coffee cake to die for.

Speaking of food, in past blogs, IӰԭve gone into depth on the microbiome, what the heck this thing is, and the foods that best nourish the microbiota (henceforth nourishing you). However, something thatӰԭs really piqued my interest is how oneӰԭs microbial gut population influences their neurological health.

Here in the U.S., AlzheimerӰԭs accounts for 60-80 percent of all dementias (Zhu et al.), which is defined as impaired ability for the brain to function. Dementia is something that will happen to all of us as we age Ӱԭ as well as the decline of our body cells as a whole Ӱԭ but the degree and rate of which this happens can be determined by how one lives their life. For example, when people ask me what muscle is the most important to train, I reply with my own question:

ӰԭWhat do you want to be stronger: your heart or your bicep?Ӱԭ

While the brain isnӰԭt physiologically a muscle, it certainly works like one. The more you use it, the better it functions. ItӰԭs one of the reasons why they start memorization so early on in your academic life: to build the neural pathways that strengthen oneӰԭs ability to remember and actively recall things. The brain is incredibly adaptive, and, because of that, a lot of interesting things tend to happen. Your ability to form biases quickens, the time it takes for you to solve problems similar to one another shortens, and so on and so forth. Your brain can be your best or worst friend, basically. Choose which one you want.

So, AlzheimerӰԭs. The pathophysiology of this disease is characterized by the deposition of amyloid beta, leading to the formation of hyperphosphorylated tau protein (which composes plaques and neurofibrillary tangles) that results in synapse loss and neuronal death (Zhu et al.). Synapses allow brain cells (neurons) to communicate with one another, similar to how a cell phone signal works. Without synapses, the brain canӰԭt talk to itself and nothing happens, adding up to the scary neurological degeneration AlzheimerӰԭs patients experience. However, remember that the rate of this deterioration (note that weӰԭre not all susceptible to this disease. I would go through your familyӰԭs history with a fine-toothed comb) is a variable dependent on lifestyle.

Use brain = brain stays.

Not use brain = brain doesnӰԭt pay rent.

As the medical field continues to find new treatments and potential cures to neurodegenerative diseases, the recognition of the fact that the Ӱԭgut microbiome plays important roles in human physiology and pathophysiologyӰԭ (Zhu et al.) is very promising for those in the field of nutrition & dietetics. In fact, a large number of studies have been linked to intestinal microbiome diseases to those such as inflammatory bowel disease, irritable bowel syndrome, colon cancer, neurological diseases (i.e. AlzheimerӰԭs and ParkinsonӰԭs), metabolic diseases, musculoskeletal diseases, osteoporosis, and gout (Zhu et al.).

Similar to how neurons ӰԭtalkӰԭ to one another via synapses, the brain and gut are very interlinked, using the vagus nerve (X) as a communication highway between them. Similarly, when one is out of balance, the other can be equally as affected. Personally, if IӰԭm too stressed out, I will not eat a single thing. Likewise, if my stomach hurts, I can be a pretty irritable person.

Speaking of behavioral patterns, ӰԭKey metabolites of gut microbes include short chain fatty acid (SCFAs), such as acetate and butyrate, which can play important roles in regulating the brain and behavior through G protein coupled receptorsӰԭ (Zhu et al.). Please keep in mind that SCFAs are formed by the indigestion of fiber, and that the function of SCFAs is primarily to support the intestinal wall of the GI tract as to protect the body from any funky visitors that may slip through the mucosal barrier. WhatӰԭs more important? Intestinal microbes are capable of secreting neurotransmitters such as norepinephrine (Alpha-1 adrenergic receptors), dopamine, and gamma-aminobutyric acid (Zhu et al.). NTs (neurotransmitters) are chemical messengers of the brain, similar to how hormones are the chemical messengers of the body.

Alright, letӰԭs back up a little bit and look at this big picture for a second.

Proper nutrition → good microbiome → good brain-body communication → happy human being → continuation of proper nutrition → repeat.

When looking at those with AlzheimerӰԭs, a clinical trial Ӱԭdemonstrated a lower abundance of Eubacterium rectale and Bacillus subtilis and a higher abundance of Escherichia/Shigella in their stools compared to other groupsӰԭ (Zhu et al.). The latter two species of bacteria are fairly nasty ones; these are the ones commonly associated with food-borne illnesses causing a plethora of symptoms in the host.

More concerningly, the Ӱԭmicrobiome of the elderly with AD shows a lower proportion of bacteria synthesizing butyrate that contributes anti-inflammatory activity and immunity regulation, as well as greater abundance of taxa that are known to cause pro-inflammatory statesӰԭ (Zhu et al.). Summarily, what weӰԭre seeing is that with age, oneӰԭs gut microbiota composition becomes increasingly dysfunctional Ӱԭ along with the rest of the body.

So...whatӰԭs the solution?

Well, we start with pro, pre and synbiotics. These bad boys Ӱԭ as mentioned in earlier articles Ӱԭ are what constitute, nourish, and help support pre-existing microbiome colonies in the GI tract. Interestingly enough, in a study done by Akbari et al., they Ӱԭfound that, compared to AD patients treated with normal milk, patients who consumed milk rich in multiple Lactobacillus and Bifidobacterium species showed a significant (P less than 0.001) improvement in the mini-mental state examination (MMSE) scoreӰԭ (Zhu et al.).

To spare you the Google: (P less than 0.001) equates to a one in a one thousand chance. Probably.

Both Lactobacillus and Bifidobacterium are vital species of the gut microbiome. While IӰԭd love to talk about them more, IӰԭm almost at four Google Doc pages and IӰԭm not sure if my editors will like that, lol.

In summary, there is a trend across the health science field that when the gut microbiome is established, maintained, and given the nutrients it needs to prosper, it does a rather good job of offering the host a variety of health benefits. Taking AlzheimerӰԭs in particular, I believe there is hope to have in buffering the effects of the disease with further research into the gut-brain connection through the work of clinical trials. Who knows? Maybe the microbes have been the answer all along. IӰԭm not saying neurodegenerative disorders will be cured or a cure will be established, but IӰԭm a firm believer that a more holistic, non-invasive treatment may be plausible in the future.

I hope everyone is having a fantastic week, and that finals arenӰԭt getting anyone down. You can only do your best, and thatӰԭs all anyone can ask for.

You got this.

With peace, love, and peanut butter,
Beatrice

Beatrice Glaviano Ӱԭ26 is a nutrition sciences major at the University of New Haven.

Works Cited

Ruairi Robertson, PhD. ӰԭWhy Bifidobacteria Are so Good for You.Ӱԭ Healthline, Healthline Media, 25 July 2017, www.healthline.com/nutrition/why-bifidobacteria-are-good. Accessed 30 Apr. 2024.

Zhu, Xueling, et al. ӰԭThe Relationship between the Gut Microbiome and Neurodegenerative Diseases.Ӱԭ Neuroscience Bulletin, vol. 37, 3 July 2021, link.springer.com/article/10.1007/s12264-021-00730-8, https://doi.org/10.1007/s12264-021-00730-8. Accessed 19 Apr. 2024.