The Beneficial Role of Bacteria in the Body
Bacteria are normally considered harmful. In reality, most are not only harmless but also helpful, playing crucial roles to aid digestion and support your health.
The intestines have some 5,000 species of bacteria and their total population is about 100 trillion - 10 times more than the number of cells in our entire body. The majority are good bacteria called "probiotics". As long as pathogenic or disease-causing organisms do not exceed 20 percent, your risk of intestinal infection is low.
Probiotics: The Good Bacteria for Digestive Health
Probiotics form an active layer of biofilm on the mucus membrane that lines the intestines. This helps defend and normalise the permeability of the intestines. In addition, probiotics:
- Compete directly with harmful microorganisms to prevent their overgrowth;
- Metabolise soluble fibres and prebiotics to short-chain fatty acids, which make the gut environment more acidic and unfavourable for disease organisms;
- Produce trace amounts of hydrogen peroxide to inhibit the overgrowth of candida yeast; 9 Produce vitamins like vitamin K2, vitamin mB12 and biotin;
- Promote the absorption of minerals;
Metabolise toxins into safer forms for excretion.
Probiotics also play a role in:
- Weight management: For people who are underweight, probiotics enhance the absorption of nutrients and help them gain weight. For others, probiotics can help avoid unnecessary weight gain by edging out microbes called firmicutes that can digest fibre (which is normally indigestible) into glucose. This could add up to 10 percent of unwanted calories. They further negate the effects of certain intestinal viruses that are known to induce weight gain.
- Disease prevention: Probiotics help prevent infectious diseases like cholera and typhoid by crowding out disease-causing organisms. At the same time, they help prevent chronic degenerative diseases that are more often linked to diet and lifestyle. This is because some types of pathogenic bacteria produce chemicals that are linked to the development of immune-related diseases.
Modulation of Estrogen Levels and Cancer Risks
In addition, probiotics help modulate the level of circulating estrogen, the female hormone that is linked to certain cancers. The liver metabolises estrogen into intermediate waste products called estrogen metabolites, which are then excreted into the intestines. There, they are processed by bacterial enzymes to estrogen to be recycled back into the body for use. This link between raised levels of circulating estrogen and imbalanced bacteria may explain the rising incidence of estrogen-linked diseases like breast cancer.
Probiotics further help to denature intestinal carcinogens to prevent gastrointestinal tract cancer. About 90 percent of carcinogenic substances require chemical alteration or bioactivation before they can actually cause cancer. An imbalance of bacteria in the guts would impact the way and the rate at which these carcinogens are altered. A good balance of probiotics helps reduce the cancer risks. To cultivate a balanced bacteria colony in the guts, regularly eat naturally fermented foods that are rich in probiotics. A supplement of probiotics will also be helpful.
Dr Shawn Ee.
BSc. BPsych. DPsych.(Clinical), Clinical Psychologist & Psychoanalytic Psychotherapist, Registered Psychologist (AHPRA; Australia)