- Excessive alcohol consumption: alcohol changes the gastrointestinal tract (GI) microbiota composition. Also, alcohol consumption disrupts intestinal barrier which against pathogens as well as alcohol-induced liver pathology including nonalcoholic fatty liver disease (NAFLD), nonalcoholic steatohepatitis (NASH), and alcoholic liver disease (ALD). There is a relationship between alcohol-induced oxidative stress, intestinal hyperpermeability to luminal bacterial products. The excessive alcohol consumptions that is detrimental to human health cause disruption of intestinal microbiota hemostasis- dysbiosis. The alcohol-induced changes can cause alcohol-related disorders, quantitative and qualitative dysbiotic changes, the development of alcoholic liver disease (ALD), and other diseases. Alcohol consumption increases GIT inflammation such as inflammatory of bowel disease (IBD), irritable bowel syndrome (IBS), celiac disease, intestinal hyper permeability and triggers tissue damage/organ pathologies and others. Alcohol consumption is associated with risk of development of cancer, abnormal function of the immune system as well as risk of acute and chronic infections, and other diseases including pancreaitis, heart disease, and circadian clock.
- Use of antibiotic: antibiotic affects negatively to gut microbiota, and the human microbiome is disrupted such as collection of cells, genes, metabolites from eukaryotes, and viruses). The overuse or use of antibiotic without intention which changes microbiome composition can cause health problems related to immune system, metabolic problems, disorders and infectious diseases. Antibiotic can affect caesarean sections associated with immunological disorders such as asthma and type 1 diabetes. Also, antibiotic can cause increasing the risk of overweight for boys during infancy. Using antibiotic rationally and frugally can prevent microbiome disruption and restore microbiota. The effects of antibiotics are based on concentration of drug, different microbial growth stages, and others. Besides, the combination of antibiotic and antibiotic-resistant bacteria can lead to reduction of mitochondrial gene expression and mitochondria per cell. Antibiotic that may contribute to enhance bacterial translocation out of the gut is related to bile acid-hydroxylating activity of clostridium scindens to against Clostridium difficile.
- Diet pattern: Diet patterns that affect on gut microbiota composition are related to combination of bacteria in the intestine called enterotypes. The three human enterotypes are Prevotella, Bacteroides, and Ruminococcus. The substrates for intestinal microbial metabolism is from food components which are indigestible for human enzymes.
- Fiber intake: The increasing fiber intake contributes to bacterial diversity and proliferation. The consumption of agro-pastoral-derived foods are related to the occurrence of bifidobacteria in the gut of adult humans. Bifidobacterium plays a role in preventing pathogenic infections by producing acetate. People who don’t have enough vitamin and nutrition intake lack of bacterial diversity. This triggers to GI inflammations and bowel diseases.
- Living environment: In article “Role of the gut microbiota in health and chronic gastrointestinal disease: understanding a hidden metabolic organ”, the study of Claesson and colleagues showed that people in long-stay care environment had high level of Bacteroidetes while people in community had high level of Firmicutes. Also, people in long-stay care environment lost community-associated microbiota associated with increased frailty and process of diseases. And, the diversity of people in long-stay care is less than people in community.
- Aging: Aging affects of microbiotic environment. For example, the infant has less complex intestinal microbiota than adults. By 2, the community structure related to the gut microbiota of infants evolves similar with adults. Besides, the age is associated with physiological changes in the gastrointestinal (GI) that compositions of gut microbiota in older people (over 65 years old) is different from young adults.
Sources:
Engen PA, Green SJ, Voigt RM, Forsyth CB, Keshavarzian A. 2015. The Gastrointestinal microbiome: Alcohol effects on the composition of intestinal microbiota. Alcohol Res. 37(2):223-36.
Langdon A, Crook N, Dantas G. 2016. The effects of antibiotics on the microbiome throughout development and alternative approaches for therapeutic modulation. Genome medicine. 8(1):39.
Guinane CM, Cotter PD. Role of the gut microbiota in health and chronic gastrointestinal disease: understanding a hidden metabolic organ. Therapeutic advances in gastroenterology. 2013 Jul;6(4):295-308.