I imagine that most of you agreed with this dietary concept. How could it possibly be wrong.
Well, this dietary concept is also wrong. It ignores the trillions of microbes in our colon. These microbes include bacteria, yeast, and fungi. The weight of these microbes is approximately four pounds. An ideal diet must include consideration for our microbiome.
The microbiome is a factor in determining obesity. AB the microbiome diversity increases, the probability of obesity decreases (Le Chatelier E. Nature 2013). By diversity, I mean the more varied species of bacteria that survive and thrive in the colon. Conversely, if the microbiome diversity decreases, the probability for obesity increases. Several bacteria have been related to non-obesity: Bifid bacteria, F. prausnitzii, Lactobacillus, and Methanobrevibacter.
It is important to understand that the microbiome has multiple interactions with our Enteric Nervous System and our Immune System. Our brain has the most nerves of any organ in our body, as you would expect. Our intestines, not our spinal cord, have the second most number of nerves. Our gastrointestinal system has extensive systems of nerves. Collectively, these nerves form the Enteric Nervous System. There is much interaction between the Enteric Nervous System and the Central Nervous System, especially the brain. Some people have termed the Enteric Nervous System the Second Brain. Our gastrointestinal tract also has a huge number of immune cells. The interaction between the microbiome, Enteric Nervous System and Immune System may be responsible for many disease processes. When there is imbalance in this complex interaction, a process known as dysbiosis occurs. A form of dysbiosis can lead to emotional and cognitive dysfunction (Emeran Mayer 2001).
In general, dysbiosis occurs with disruption of the microbial ecosystem. Many Central Nervous System manifestations may occur, including the following: Autism, anxiety, depression, irritable bowel syndrome, chronic pain, etc. (E. Mayer 2001).
In the future, we may know enough about the microbiome to eliminate the bad acting microorganisms and transplant the healthful microorganisms. We are not at that stage yet. Therefore, our best strategy is to increase the diversity of our microbiome. We can increase diversity with substances called Prebiotics. Prebiotics are substances that allow many different types of microorganisms to thrive. Recall that plant based food is composed of cells with cell walls. Cell walls are indigestible portions of the plant food. These cell walls contribute to dietary fiber. When the dietary fiber is soluble, it can be metabolized by the microbes in our colon, typically in a process of fermentation. This nourishes the microorganisms.
The insoluble fiber in plant food does not dissolve in water but provides hulk for the stool and helps the colon absorb water. Perhaps, Cristina Warinner, Ph.D. put it best: “The whole point of dietary fiber is for our microbes.”
Many fruits and vegetables can serve as Prebiotics. Interestingly, there has been a flurry of research involving walnuts as a potent prebiotic. (Nakanishi, M., 2016; Byerley, L., 2017; Bamberger, C., 2018; Holscher, H., 2018).
Alternatively, there are ways to decrease microbiome diversity. For instance, a diet with excessive meat an cheese can rapidly decrease diversity. Further, unnecessary antibiotics will decrease microbiome diversity.
In addition to Prebiotics, our microbiome can be enhanced with Prohiotics. Probiotics are essentially living bacteria in the foods of our diet. This came to light over 100 years ago. Iiya Mecbnikov, Ph.D. from the Pasteur Institute in Paris studied 36 countries in the early l 900s. He found that Bulgaria had the most centenarians (citizens reaching the age of 100 years). Dr. Mechnikov attributed this longevity in Bulgaria to homemade yogurt. Since that time, numerous scientists have demonstrated that the bacteria in yogurt provide multiple health benefits, including increasing the diversity of our microbiome. In addition to yogurt, Probiotics can be found in non-pasteurized cheese and fermented products.
Probiotics can also be bought as a pill. This has ballooned into a multibillion dollar industry. It is important to keep in mind that the bacteria in unpasteurized cheese and the bacteria added back to pasteurized yogurt have the cheese and yogurt as a food source for the bacteria. Additionally, the cheese and yogurt serve to protect the bacteria from our stomach acids. When it comes to Probiotics in a pill, several concerns come to mind.
Can the bacteria survive the store shelf life? Can the bacteria survive our stomach acid? Can these Probiotics successfully become part of our microbiome?
Hopefully, the Prebiotics and Probiotics discussed above can help create a diet that is beneficial to you and to your microbiome. If not, there is a potential procedure, known as a fecal transplant. This means that somebody else’s feces is put into your colon.
Finally, another thought about artificial sweeteners. Earlier, I discussed how artificial sweeteners stimulate the brain to stimulate the pancreas to increase insulin secretion in preparation for a sweet substance entering the gastrointestinal system. Additionally, artificial sweeteners may alter the colonic microbiome (Jonathan Suez, Nature 2014). This effect of artificial sweeteners on our gut microbes may lead to another pathway that results in insulin resistance.