Our intestines are home to 100 trillion of bacteria with the ideal gut flora ecosystem of 85% good bacteria. Consuming antibiotics upsets the gut flora balance as they kill the good bacteria or stop them from multiplying.
Most of the antibiotics are “broad spectrum’ in which they are unable to target a single bacteria strain, hence, a wide range of bacteria species in the intestines will be wiped out at the same time. Most people will experience abdominal bloating and diarrhoea following a course of antibiotics, this is the side effect of antibiotics that cause disturbance in the composition, diversity and functions of gut flora. The microbiota disturbance in the intestine can persist for years. Researchers in Sweden found that the composition of gut flora of a group of healthy volunteers had not returned to their original state, even after 2 years following a course of antibiotics for only 7 days. Another research also confirmed that even short-term intake of antibiotics can lead to stabilisation of resistant bacterial populations in the intestines that persisted for years.
A disrupted gut flora balance is associated with many different diseases. One of the most prominent problems is the increased susceptibility to intestinal infections, caused by newly acquired pathogens or sudden overgrowth of bad bacteria present in the intestines. As the gut flora also plays a role in many physiological processes such as regulation of immune functions and metabolic homeostasis, a disrupted gut flora balance may also lead to:
- Autoimmune diseases (inflammatory bowel syndrome, diabetes)
- Allergic diseases
- Yeast infection
- Antibiotic-associated diarrhoea
- Leaky Gut Syndrome
- Antibiotic resistance
According to World Health Organisation, antibiotic resistance is now a global issue due to misuse and overuse of antibiotics. Antibiotic resistance occurs when microorganism is able to withstand the effects of an antibiotic. When this happens, there is a greater chance of it being resistant to antibiotics when one gets the next infection. As a result, the infection persists in the body with a higher risk of infecting others; and a stronger antibiotic is needed to clear the infection. An ex vivo study of faecal samples incubated with various antibiotics, showed an increased proportion of gut bacteria with damaged membrane; the bacteria have been observed to possess genes with antibiotic resistance.