How Probiotics Keep Us Healthy

The human gut has hidden clues to many complex issues related to our well-being.

- Sanghamitra Chakraborty

AMIT VERMA*, 32, HAD A BAD BOUT OF STOMACH infection. So he went to his chemist and helped himself to some anti- biotics, available easily over the counter. However, when his symptoms did not subside after a couple of courses of antibiotics, he approached Dr Ajay Bhalla, a gastroenterologist for help. Bhalla immediately spotted Verma’s case as yet another instance where the patient had taken antibiotics injudiciously and developed antibioticinduced diarrhoea. He asked Verma to stop all medication and put him on probiotics for five days, which ultimately settled his stomach.

What exactly are probiotics and how do they keep us healthy? Before we get to that, let’s first look into our gut. Our intestines are aflush with a vast colony of bacteria—some 1,000 trillion of them—of different species. These intestinal flora, or microbiota, together form an environment known as the microbiome and make up a sort of organ, whose purpose is being revealed to science only now. The gut and the flora are in a mutually beneficial relationship and the microbiota’s influence on our body is nothing short of profound.

According to Justin and Erica Sonnenburg, researchers at the department of microbiology and immunology at Stanford Medicine and authors of The Good Gut: Taking Control of Your Weight, Your Mood, and Your Long-Term Health, microbiota release chemicals during the fermentation processes that take place in our gut. “These reaction products perform important biological tasks for us: tuning our immune system, helping us fend off disease-causing bacteria and regulating our metabolism,” they write.