The intestinal microbiome and health

Abstract

Purpose of Review A diverse array of microbes colonizes the human intestine. In this review we seek to outline the current state of knowledge on what characterizes a “healthy” or “normal” intestinal microbiome, what factors modify the intestinal microbiome in the healthy state and how the intestinal microbiome affects normal host physiology Recent Findings What constitutes a “normal” or “healthy” intestinal microbiome is an area of active research, but key characteristics may include diversity, richness and a microbial community’s resilience and ability to resist change. A number of factors, including age, the host immune system, host genetics, diet and antibiotic use appear to modify the intestinal microbiome in the normal state. New research shows that the microbiome likely plays a critical role in the healthy human immune system and metabolism. Summary It is clear that there is a complicated bi-directional relationship between the intestinal microbiota and host which is vital to health. An enhanced understanding of this relationship will be critical not only to maximize and maintain human health but also to shape our understanding of disease and to foster new therapeutic approaches.

Association of Dietary Patterns With Risk of Colorectal Cancer Subtypes Classified by Fusobacterium nucleatum in Tumor Tissue

“…The potential role of diet in modulating the risk of a variety of diseases including colorectal cancer has been widely recognized 23,34 According to the World Cancer Research Fund and American Institute for Cancer Research, foods with fiber including whole grains are one of the strongest factors linked to decreasing the risk of colorectal cancer. 35 Importantly, however, there has been considerable heterogeneity in the epidemiological data associating prudent dietary patterns and its major components with colorectal cancer.…”

Extra-gonadal sites of estrogen biosynthesis and function

“…The microbiome is capable of digesting large molecules into simpler ones that can be efficiently reabsorbed by the host. The importance of a healthy microbiome has been well published (104-108), and multiple pathologies have been correlated with poor diversity of the microbiome, including irritable bowel (IBS) (109), osteoporosis (110,111), and gluten intolerance (112). Therefore, controlling the microbiome is paramount to maintaining an optimally functioning GIT.…”

Maternal–Child Microbiome

“…It is comprised roughly 500–1,000 unique species that have key roles in food digestion, energy and nutrient extraction, drug metabolism, regulation of host metabolism, and modifying immune response (Tuddenham & Sears, 2015). The composition and function of the gut microbiota have been implicated in a wide range of health outcomes, including obesity, atherosclerosis, diabetes, gastrointestinal disorders, and developmental and mental health (Manges, Steiner, & Wright, 2016; Rogers et al, 2016; Tuddenham & Sears, 2015). Specifically in maternal–child health, the gut microbiota composition and function develop throughout the first two years of life and then shift during pregnancy and appear to differ in women with pregnancy-associated complications such as gestational diabetes (Koren et al, 2012).…”