Save yourself • Limit the amount of highly processed, chemical, preservative and transfat containing food that you eat. • Eat at least four helpings of fruit and vegetables a day. • Add natural yogurt to the diet. • Try to eat cereal with fibre, not the highly processed polished variety. • Do not opt for a caesarian unless there is a medical reason for doing so. • Breast-feed your baby for a year. • Exercise is a panacea for all illness. It is proven to help good gut bacteria grow.

Bacteria are invisible to the naked eye but they are everywhere — in the soil, on our skin, in the air we breathe, and, most importantly, inside our bodies, particularly in our intestines. We wage an ongoing war on bacteria using soaps, disinfectants, antiseptics and antibiotics. It is a losing battle with periods of truce.

Babies live in a sterile environment in the uterus. They start acquiring bacteria during the birth process, which (if it is a normal delivery) is messy with close contact between the baby and the mother’s skin, intestines and blood. This seeding colonises the baby’s skin and gut. Most of the organisms are harmless. As they thrive they help with the digestion of breast milk. They also fend off attacks from stray disease-causing bacteria and help develop appropriate immunity.

In children born by caesarian section, there is no initial seeding with appropriate friendly bacteria. The immune systems of these babies do not develop quickly or appropriately. This makes them prone to allergies and infections.

The composition of breast milk has baffled scientists. Despite repeated and expensive efforts, breast milk could not be replicated in the laboratory. It contains immunoglobulins from the mother that protect from childhood diseases and diarrhoea. It contains complex carbohydrates called oligosaccharides, which the baby’s gut enzymes do not digest. It actually serves as food for certain beneficial bacteria (bifidobacteria), which thrive and multiply and crowd out disease (diarrhoea)-causing bacteria.

By the age of three, gut bacteria resembles that of the adult. It then remains stable and relatively unchanged till bacteria-altering events such as illnesses or antibiotic usage occur.

Gut bacteria aid digestion and absorption of nutrients from the gut. They want to be well fed, so they release chemicals that effect human appetite. They control inflammation. They manufacture neurotransmitters like serotonin, vitamins from the B complex group and vitamin K. They influence our weight, our mood and our health. They may be responsible for obesity, autoimmune diseases, stress levels and mood swings.

We can alter our gut flora in subtle, unintentional ways. Chlorinated drinking water and miniscule amounts of soap, toothpaste and hand sanitizers kill good and bad bacteria, altering the ratio and changing our internal environment. The biggest threat comes from antibiotic usage. The “broad spectrum” antibiotics do just that —they kill good and bad bacteria over a wide spectrum, completely changing our internal environment. We may have got rid of the infective “bug” but have left our bodies weaker and damaged after the treatment.

Dr Gita Mathai is a paediatrician with a family practice at Vellore. Questions on health issues may be emailed to her at yourhealthgm@yahoo.co.in