Microbiome and bacteria
The human microbiome is a diverse community of microbes that work together to keep your body healthy. It plays a critical and complex role in supporting many different bodily processes. You have trillions of microbes both on and in your body, made up of bacteria, fungi (including yeasts), viruses and protozoa.
Both good and bad bacteria live in the gut, mouth, female genitourinary tracts, skin and lungs. The good bacteria support your immune function and control inflammation, help your body digest food, prevent the bad bacteria you have consumed or encountered from multiplying, create vitamins, and break down and absorb medications. When you get an infection, bad bacteria knock your system out of balance.
The discovery of antibiotics, which are chemicals that combat bacterial infections, was a huge medical advance, and has saved many lives. But there is a downside to antibiotics as they also significantly disrupt the vast number of protective bacteria in the body – most importantly in the digestive system (which also houses 70% of your immune system) and in the female genitourinary tracts. They can also cause side effects such as nausea, vomiting and diarrhoea, especially in the young and the elderly.
Antibiotic use in pregnancy has been associated with increased allergies in infants, notably dairy allergy, asthma, eczema and hay fever, and antibiotic use in early life has been associated with coeliac disease, allergies, obesity and autism.
There is also a concern that existing antibiotics have been used unnecessarily often in both humans and animals (for e.g. coughs, colds, sore throats and flu) which has encouraged resistance and greatly reduced their efficacy. Worryingly, there are now very few, if any, new antibiotics in development.
Prebiotics are complex carbohydrates that feed the microorganisms in your gut, essentially they are the ‘food source’ for good bacteria. Prebiotics include inulin, pectin and resistant starches. Eating a well balanced diet rich in vegetable fibre every day helps to maintain the amount of good bacteria at sufficient levels.
Probiotics are a combination of live beneficial bacteria and/or yeasts that naturally live in your body. The most common probiotic bacteria are lactobacillus and bifidobacterium, and the most common yeast found in probiotics is saccharomyces boulardii.
Probiotics can be used to help relieve inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), yeast infections such as candida, genitourinary tract infections, gum disease, lactose intolerance, eczema, upper respiratory infections such as ear infections, the common cold and sinusitis, constipation, acid reflux, diarrhoea and gas.
Probiotics have been trialled as a preventive strategy for Clostridioides Difficile (C. diff) infection in hospitalized children and adolescents, and have been found to reduce the risk of infection and save cost. Another study demonstrated a positive impact of probiotic consumption on health outcomes in flu-like respiratory tract infections.
Fermented foods labelled ‘live and active cultures’ such as yoghurt, cottage cheese, sourdough bread, tempeh and pickles such as sauerkraut or kimchi – and fermented drinks such as kombucha, a type of fermented tea, and kefir all provide useful dietary probiotics.
A supplement that combines a probiotic and prebiotic is called a synbiotic.
Probiotics alongside antibiotics
Studies have shown that probiotics rapidly restore a healthy level of gut and other intestinal bacteria during and after antibiotic use, and may also prevent antibiotic diarrhoea which can continue for some months after antibiotic use. In addition, studies show that probiotics inhibit the development of antibiotic resistant bacteria during and after antibiotic use.
Probiotics should be taken at least two hours apart from any antibiotic (and preferably midway between antibiotic doses), and continued for at least 2-4 weeks after completion of the antibiotic course.
Preventive measures every day
Regular probiotics can be taken as a daily preventive to support the body’s natural immunity and prevent initial infections. At a cost of less than a pound per day for top quality probiotics, taking probiotics every day is a useful way to improve your health, alongside anti-Covid immune boosting zinc, plus Vitamins C and D.