The Microbiome and Human Health

In health magazines, it is declared that maintaining a healthy microbiome is integral to physical and mental health — but what is our microbiome, and what does it do? In short, our microbiome is the microorganisms, like bacteria, that live in and on our bodies. They improve our health through various mechanisms like protecting us against pathogens and digesting some foods. However, while certain microbiota have been linked to enhancing health, others have been linked to causing disease.

The most commonly discussed microbiome in humans is the “gut microbiome,” or the microbiome from our gastrointestinal tract. In healthy individuals, this microbiome is known to be diverse, but its composition varies from person to person and depends on geographical location¹. According to an article in the Journal of Biosciences, specific changes in a healthy gut microbiome can create dysbiosis, or an imbalance, in the normal microbiome. This can lead to diseases, such as obesity, inflammatory bowel disease, and diabetes. For example, it has been found that a large increase of Firmicutes and a large decrease in Bacteroidetes is correlated with obesity².

The gut microbiome is not only related to intestinal diseases, but seems to have a connection to respiratory health as well. Studies of the gut-lung axis show that the gut and lungs are in constant communication, and the gut microbiota can directly affect lung health. For example, in an experiment where strains of Lactobacillus are ingested, mice were protected from influenza-like illnesses, Streptococcus pneumoniae and Klebsiella pneumoniae³.

Although we know that changes in the microbiome can lead to disease, how do changes in the human microbiome occur? For the gut microbiome, diet plays an effective role in its homeostasis. It has been found that high fat and low fiber diets result in a less diverse gut microbiome, while high fiber and high protein diets promote the growth of certain microbiota. Other behaviors that can shape the gut microbiome are exercise and exposure to the environment. Engaging in regular physical exercise and exposure to the environment will improve the gut microbiota⁴. Interestingly, a method that proves to have significant results in restoring the gut microbiota is fecal microbiota transplantation⁵. Our microbiome may be unseen and not commonly discussed in health topics, but it is integral to our health. By maintaining a healthy lifestyle, we can ensure that we have a good microbiome that will protect us from diseases and pathogens.

Citations:

1. Das, Bhabatosh, and G Balakrish Nair . “Homeostasis and Dysbiosis of the Gut Microbiome in Health and Disease.” UNC Chapel Hill Libraries. Journal of Biosciences, September 20, 2019. https://link-springer-com.libproxy.lib.unc.edu/article/10.1007/s12038-019-9926-y.
2. Das, Bhabatosh, and G Balakrish Nair . “Homeostasis and Dysbiosis of the Gut Microbiome in Health and Disease.” UNC Chapel Hill Libraries. Journal of Biosciences, September 20, 2019. https://link-springer-com.libproxy.lib.unc.edu/article/10.1007/s12038-019-9926-y.
3. Wypych, Tomasz P, Lakshanie C Wickramasinghe, and Benjamin J Marsland. “The Influence of the Microbiome on Respiratory Health.” UNC Chapel Hill Libraries. Nature Immunology, September 9, 2019. https://www-nature-com.libproxy.lib.unc.edu/articles/s41590-019-0451-9#Sec7.
4. Das, Bhabatosh, and G Balakrish Nair . “Homeostasis and Dysbiosis of the Gut Microbiome in Health and Disease.” UNC Chapel Hill Libraries. Journal of Biosciences, September 20, 2019. https://link-springer-com.libproxy.lib.unc.edu/article/10.1007/s12038-019-9926-y.
5. Wypych, Tomasz P, Lakshanie C Wickramasinghe, and Benjamin J Marsland. “The Influence of the Microbiome on Respiratory Health.” UNC Chapel Hill Libraries. Nature Immunology, September 9, 2019. https://www-nature-com.libproxy.lib.unc.edu/articles/s41590-019-0451-9#Sec7.