Emotion, Inflammation, and Adiposity: The Mind-Heart-Gut Connection

The connection between the heart and the mind remained for much of history the province of romantics and poets. The connection between heart and stomach likewise remained the domain of chefs and gourmets. Now it seems that science is beginning to link this physiological triumvirate through the most unlikely of sources; bacteria.

Or more specifically, our individual gut microbiome. That is the collection of the estimated  30-100 trillion cells comprised of over 1000 different species that inhabit our digestive tract. There is increasing evidence that alteration of the normal gut microbiome can result in an environment that promotes ongoing inflammation and the disabilities and diseases of modern civilization associated with them.

Research has examined the effect of non-caloric artificial sweeteners (NAS) on the gut microbiome and human health (1).  Artificial sweeteners are ostensibly marketed as a more healthful alternative to similar, but more energy dense products. The theory being that such NAS, since they are essentially unmetabolized by humans, would pass inertly through the digestive system. By reducing energy intake through reduced caloric consumption there would be weight loss and a decrease in conditions like diabetes and cardiovascular disease.

But many previous studies have shown a somewhat paradoxical association between increased diet drink consumption and increasing levels of obesity (as measured by the body mass index; BMI), diabetes, and cardiovascular risk. It is something that argues against a simply quantitative approach, against simply counting calories, to achieve health and wellness. Research has confirmed the link between glucose intolerance (the hallmark of diabetes) and the consumption of NAS.

The key to the relationship revolves around the quality of the comestibles consumed. While NAS were not metabolized by human cells in the digestive tract, they had a profound effect on the human gut microbiome. For certain individuals, those effects were measurable in as little as one week after beginning the ingestion of such foodstuffs. Those effects include increased abdominal adiposity (increased belly fat deposition), impaired liver function, and glucose metabolism associated with the development of diabetes.

But where does our mind and our free will enter into this equation? Obviously, what we decide to pack into our skull cave is ultimately our own choice. But those conscious decisions are heavily influenced by our subconscious and our emotions. And it turns out that emotion, in the form of stress, can have a profound effect on the development of inflammation and disease.

Research has also examined the role of stress in producing inflammation in both obese non-obese participants (2).  Sixty-seven people were examined at baseline and under stressful conditions such as a difficult interview with challenging math problems. Cortisol, a hormone released during periods of stress and interleukin-6 (IL-6), a marker for increased inflammation were measured.

The inflammation associated with interleukin-6 has been correlated with the number of conditions such as atherosclerosis, type 2 diabetes, cancer, and fatty liver disease. Both groups exhibited increases in both cortisol and IL-6. However, those with a greater BMI exhibited a more pronounced and longer-lasting response resulting in higher and more sustained levels of circulating IL-6 compared to those with a lower BMI. Interestingly, those with a lower BMI also had lower baseline levels of IL-6. Abnormalities of the gut microbiome have also been associated with increased weight and adiposity.

Taken together, these types of findings indicate an intricate balance between our emotions and our mind and the happiness and health of our heart. The scales upon which these balance is the health of our digestive system.

Disease, particularly many of the chronic disabilities and diseases that confront our modern society are the result in large part due to an interaction between our genetics and our environment. Our most intimate and powerful environmental interaction occurs through what we choose to eat. The final expression of what we choose to ingest from our external environment is mediated by our own internal environment; our individual human gut microbiome. This relationship and its implication for dietary choices, health, and wellness are discussed in great detail in both The Fallacy Of The Calorie: Why The Modern Western Diet Is Killing Us And How To Stop It and Food Shaman: The Art of Quantum Food.

In short summation; the quality of our food matters. Character counts. Choose wisely.

1 (Suez, et al., 2014)

2 (McInnis, et al., 2014)

Bibliography

Fenster, MS. The Fallacy Of The Calorie: Why The Modern Western Diet Is Killing Us And How To Stop It. Koehler Books. 2014.

Fenster, MS. Food Shaman: The Art of Quantum Food. Post Hill Press. 2018

McInnis, C., T. M., Gianferante, D., Hanlin, L., Chen, X., Breines, J., . . . Rohleder, N. (2014). Measures of adiposity predict interleukin-6 responses to repeated psychosocial stress. Brain Behav Immun, (14)00410-3. doi: 10.1016/j.bbi.2014.07.018.

Suez, J., Korem, T., Zeevi, D., Zilberman-Schapira, G., Thaiss, C., Maza, O., . . . Elinav, E. (2014). Artificial Sweeteners Induced Glucose Intolerance by Altering the Gut Microbiota. DOI:, doi:10.1038/nature 13793.