Got a gut feeling? Well, you might just be right!
Did you know that humans have been around for 200,000 years? 98% of our existence has passed with an average life span between 19 – 25 years. Now isn’t that shocking! (1). Yet, the exponential growth in science and medicine over the last two centuries has increased our life expectancy vastly.
Researchers in the past decade or so, have been looking into factors that determine aging, longevity, and ability to adapt to environmental influences. One such factor that is associated with aging, is the microbial composition of our gut. Now, this might sound strange. But scientists will now be able to age you if you were to handover your stool sample to them! (2)
Researchers study bacteria that live in our digestive system for various reasons. One of them is to understand the changes in bacterial assemblages over time. The microorganisms in our gut have been studied across large groups of people. This includes people of diverse age classes, ethnicities, and varied environmental exposures. These studies have arrived at very interesting results. It suggests that, as we age, our gut microbiota evolves and adapts to the requirements of that phase of our life (1,2).
Studies with regard to gut microbiota and age started surfacing in the early 2000s. Sara Quercia and her team, from the University of Bologna in Italy, have been part of such researchers. It focused on the changes in gut microbiota in humans based on a number of variables. The variables included age, daily life practices, genetic condition of the person, dietary shifts and host physiology (3).
For example: During infancy, the gut microbiota is meant to boost the immune system, brain development, and nutritional absorption. Whereas in an elderly person, the gut microbiota is focused on enhancing energy intake by breaking down complex sugars (1).
We were all born completely sterile, but within a few hours of birth, microbes start living inside us. And there begins the complex relationship between our gut and the tiny beings that will continue to aid us for the rest of our lives. Interestingly, some studies have tried to see if there is any relation between this “pioneer microbiome” across different modes of birth (4).
It was found that babies delivered vaginally, imbibed the microbes from the mother’s birth canal. And those born through cesareans were found to have the same microbes as on the mother’s skin. The “pioneer microbiome” usually consists of facultative aerobes. But with the intake of breast milk, the gut microbiota changes to obligate anaerobes.
Slowly as infancy ends, the gut microbiota starts resembling that of an adult. Some argue that a mature adult’s gut microbiota might even attain some stability. But it is well established that an elderly gut holds more aero-tolerant and pathogenic species. Such composition of microbes will result in more energy needed to break down sugars and receive energy. This will ultimately lead to age-related diseases (4).
Professor Yatsunenko from the Center for Genome Sciences and Systems Biology at the Washington University School of Medicine conducted an interesting study. They characterized gut microbiota from 531 people living in three different countries (5). He along with his co-authors noticed that across these three groups, the way the infant gut microbiota developed remained comparable. However, there were clear differences between the microbiota assemblage of those from the USA and the other two countries. He speculates that the effects of westernization and the varied dietary system might be the reason behind this. To know what your gut microbiome looks like, get yourself tested at Viome.
Another group of scientists from the Center for Microbiome Innovation at the University of California, San Diego have analyzed over 11,000 stool samples for the American Gut Project. They have come out with some very interesting results (6). This study has shown that those who eat a larger variety of vegetables have a much diverse gut microbiota. This is in comparison to those who eat fewer and less varied vegetables. Also, eating different vegetables seems to help us metabolize food in more than one way. If you never listened to your mother before, listen to her now and eat as many different vegetables as possible!
Looking back at these studies, scientists often tend to pose a question which might be slightly difficult to answer. It is true that the gut microbiota can reveal your age, but could it also be that your aging process is governed by what’s in your gut? Researchers have linked poor gut microbiota to depression, behavioral changes, pronounced physiological stress and increased risk of diseases (4,6). Therefore, it is vital that one takes care of the microbes living in their digestive system and make sure to always listen to our gut. Get your gut microbiome tested at Viome and find out which foods you, and only YOU need.
1 - Valle Gottlieb, M.G., Closs, V.E., Junges, V.M. and Schwanke, C.H.A., 2018. Impact of human ageing and modern lifestyle on gut microbiota. Critical Reviews in Food Science and Nutrition, 58(9), pp.1557-1564.
2- O’Toole, P.W. and Jeffery, I.B., 2015. Gut microbiota and ageing. Science, 350(6265), pp.1214-1215.
3- Quercia, S., Candela, M., Giuliani, C., Turroni, S., Luiselli, D., Rampelli, S., Brigidi, P., Franceschi, C., Bacalini, M.G., Garagnani, P. and Pirazzini, C., 2014. From lifetime to evolution: timescales of human gut microbiota adaptation. Frontiers in microbiology, 5, p.587.
4- Galkin, F., Aliper, A., Putin, E., Kuznetsov, I., Gladyshev, V.N. and Zhavoronkov, A., 2018. Human microbiome ageing clocks based on deep learning and tandem of permutation feature importance and accumulated local effects. bioRxiv, p.507780.
5- Yatsunenko, T., Rey, F.E., Manary, M.J., Trehan, I., Dominguez-Bello, M.G., Contreras, M., Magris, M., Hidalgo, G., Baldassano, R.N., Anokhin, A.P. and Heath, A.C., 2012. Human gut microbiome viewed across age and geography. nature, 486(7402), p.222.
6 - McDonald, D., Hyde, E., Debelius, J.W., Morton, J.T., Gonzalez, A., Ackermann, G., Aksenov, A.A., Behsaz, B., Brennan, C., Chen, Y. and Goldasich, L.D., 2018. American gut: an open platform for citizen science microbiome research. systems, 3(3), pp.e00031-18.