When constant consumption of junk food caused gastrointestinal problems for Kavya (25), she started taking probiotics drinks on a regular basis, bought over the counter from the chemist.
Many paediatricians say parents are regularly giving probiotics supplements to young children to boost their immunity.
As the significance of a healthy gut in overall health, impacting everything from digestion, immunity and nutrient absorption to mental well-being, and even cardiovascular health, emerges, gut health has not only become the focus of research and developing new treatments but gained traction in common people.
An unhealthy gut or dysbiosis, linked to factors like poor diet (low fibre, high sugar, processed foods), stress, smoking, alcohol, environmental toxins, and certain medications (antibiotics, acid suppressing /antacids), can disrupt the gut health and may cause many serious health issues like inflammatory diseases, inflammatory bowel disease, metabolic syndrome, autoimmune diseases.
Different approaches from dietary changes to medical procedures are being used to improve the microbial ecosystem of our gut. However, probiotics (live microbes) and prebiotics (food for microbes) have gained much attention for their role in gut health due to the ease with which they can be had or are available commercially over the counter at the chemist, supermarkets or online.
What are probiotics
The International Scientific Association for Probiotics and Prebiotics defines probiotics as groups of ‘live’ microorganisms which when administered in appropriate dosages or quantities will confer some benefit to the health.
One of the most important components of this definition is that these microbes are viable or living and provide a health benefit. The definition emphasises that the term should be restricted to those groups of microorganisms that have been shown to benefit the humans in controlled clinical studies where these drugs are tested against placebos. This clearly indicates that some of the commercial products sold under the garb of ‘probiotics’ do not even qualify to be labelled as a probiotic.
Many fermented foods (which have live bacterial culture), often dubbed as probiotics, would be outside the definition of probiotics. Similarly, all yogurts cannot be labelled as probiotic. The primary reason is that it may not be possible to separate the health benefit of microorganisms from the food component of these foods.
How do probiotics work
The probiotics are designed to survive the journey from mouth to the colon i.e they can survive gastric acid, bile and other intestinal secretions. They colonise the gut and make our intestine relatively hostile for harmful microbes. The probiotics can also strengthen the barrier in the gut ensuring that harmful microbes and material do not reach/enter our body. However, this colonisation by probiotics is only temporary and the organisms/strains disappear when the probiotic is discontinued.
Common probiotics
Certain bacterial species are accepted to have species specific benefits and, therefore, may be applicable across strains of these bacteria (like Lactobacillus and Bifidobacterium). These should be considered as food based or supplement based probiotics. The labelling of these organisms as probiotics is based on the assumption that they favourably modulate the gut environment and increase the healthy microbes in our gut, help create a healthy gut, and improve the immune system overall but there may not be a direct, specific health benefit in a specific condition.
However, only some probiotics strains have been shown to benefit in a disease during clinical researches. And the beneficial effect of these strains will only be possible if had in high strengths, which may not be viable in commercially available probiotics. Also, it is important to note that benefits are often strain-specific for probiotics and condition-specific.
What are prebiotics
Prebiotics are specific types of non-digestible dietary fibres. These serve as food for beneficial microbes, promoting their growth and activity of colonising the gut. Sometimes a combination of prebiotic and probiotic can also be provided and is called as a symbiotic.
A daily dose or not
Unlike vitamins or minerals, there is no ‘recommended daily allowance’ for probiotics. Nutritional guidelines suggest an intake of 25-35 gm of dietary fibre every day.
Adverse effects
Excessive prebiotics can cause bloating and gas formation because of the fermentation in our colon. Probiotics are usually safe although occasional reports of sepsis in critically-ill individuals have been noted.
Who needs supplements
In general, healthy individuals do not need probiotics. These may be of benefit in specific situations like preventing/ reducing duration of antibiotic associated diarrhoea, prevention of traveller diarrhoea or in specific situations like irritable bowel syndrome or inflammatory bowel disease. The specific probiotic preparation to be used should be after discussion with doctor so that the strains beneficial in a particular condition are used.
— The writer is Additional Professor, Department of Gastroenterology, PGI, Chandigarh
Dietary sources of prebiotics & probiotics
Prebiotics: These are found in carbohydrate-rich plants. They are technically soluble, fermentable fibres and may include chicory root (which has inulin), garlic, onions, asparagus, unripe bananas, oats and apples.
Probiotics: The best source of probiotics is fermented food. However, a crucial distinction must be made: not all fermented foods contain probiotics. If a food is fermented but then heated (pasteurised or baked), the heat kills the bacteria. Yogurts, kefir, kanji, sauerkraut, kimchi, kombucha — all contain live bacteria though they cannot be labelled as probiotics. However, these foods are believed to have healthy impact on our gut.
Factcheck
Studies show probiotics are beneficial in gut disorders (IBD, IBS, infections, diarrhoea in children and antibiotic-associated diarrhoea), for immune support and mental health (anxiety, depression), and metabolic issues like type 2 diabetes, though results vary by strain/type. Certain probiotics can improve lactose digestion, glycaemic control and insulin sensitivity. Studies suggest prebiotics and probiotics may alleviate stress by modulating the gut-brain axis. Studies on prebiotics show they benefit gut health by feeding good bacteria, mineral absorption, and reduce risk of colon cancer. Prebiotics help in weight management (by lowering hunger hormone, increasing satiety and reducing cravings), beneficial for heart health (blood pressure), and neurological functions (brain response to food cues). Prebiotics also improve antibody responses to vaccines, boost immunity and reduce infections in infants and elderly.