By Dr Rohit Arora
Long term wellbeing of an individual is an amalgamation of several variables that are often connected or disparate from each other. We know diet, physical exercise and sleep have a direct bearing on the health of a person, but little is known about the critical role that immunity plays during infancy and beyond, especially during the first 1000-day period, which if ignored can exacerbate the health foundation of an individual.
By definition, the first 1,000 days (F1000D) is the period marked from the time of conception until the child is two years old. During this period, there is rapid development of the brain and immune system of the baby. Poor immunity also has a direct impact on the brain development and hence adequate nutrition to build strong immunity and therefore prevent infections becomes imperative. A fortified immune system becomes a pivot in ensuring healthy growth during this period.
The human gut plays a dual role in the body. We normally associate gut with digestion, and absorption of food and elimination of waste but it also has a pivotal role in cementing the immunity of an individual. About 70-80 per cent of the immune cells are located in the gut, making it the largest immune organ and the primary line of defence against pathogens.
Human gut is host to a plethora of ‘microbiota’. The gut microbiota is made up of beneficial, harmless and harmful microorganisms, which includes bacteria, fungi and viruses. It was believed that the gut is sterile when the baby is inside the womb and the bacteria colonises human gut right during and after birth. The bacteria which colonises the gut post-birth squarely impact the gut immune system.
The beneficial bacteria acquired during the birthing process aid in reducing the pH of the gut leading to the decimation of pathogenic bacteria along with promoting the growth of good bacteria.
We all know that infants are born with an immature immune system due to limited exposure to antigens in the womb. After birth, a baby is fed breast milk which acts as a source of complete nutrition for the infant. That’s why, WHO recommends exclusive breastfeeding for up to six months of age and to continue breastfeeding until two years of age and beyond with timely introduction of complementary feeds.
There are components in human milk that help build gut health and immunity. Breast milk contains components that both actively and passively modify the immune system of an infant. One such component is oligosaccharides. After carbohydrates (lactose) and fats, oligosaccharides are the third largest component of breast milk (even more than proteins). It is speculated that there are over 1000 oligosaccharide structures present in breast milk of which till date only about 200 structures have been identified.
Oligosaccharides cannot be digested by the enzymes present in the mouth, stomach and small intestine and hence pass undigested to the large intestine wherein it acts as a food for the good intestinal microbiota and helps it grow thereby rendering a prebiotic effect.
In infants, it helps promote growth of organisms such as Bifidobacteria (bifidogenesis) and lactobacilli which in turn helps Inhibit the adherence of pathogenic/harmful organisms to the intestinal wall thereby preventing the pathogen from entering into the bloodstream and causing infection. Consumption of oligosaccharides by these beneficial bacteria also changes the intestinal environment by turning it the right shade of acidic. This acidic environment is much needed as it further promotes the growth of good bacteria, inhibits bad bacteria and thus reduces infections and associated illnesses. Apart from human milk, traces of prebiotics have been found in goat and donkey’s milk. Bovine milk is a poor source of prebiotic oligosaccharides. However, as per WHO, these other sources of milk are not advised to be consumed in case of infants, until one year of age.
So, to enhance immunity of the gut, prebiotics which are non-digestible dietary fibre that help as it affects the host by selectively stimulating the growth or activity of a limited number of bacteria in the colon can be taken from external sources as well. e.g. inulin, acid oligosaccharides, Fructo-oligosaccharides (FOS), Galacto-oligosaccharides (GOS). Among these, the most studied prebiotic is the combination of Galacto-oligosaccharides and Fructo-oligosaccharides (GOS & FOS) in the ratio of 9:1. The combination of scGOS/lcFOS (9:1) mimics the oligosaccharides present in human milk due to their high galactose content, varying chain length and molecular weight distribution.
There are about 30 clinical studies and 55 publications in international peer reviewed journals on the beneficial effects of GOS & FOS. These studies reveal that the combination of GOS & FOS in the ratio of 9:1 increases the count of beneficial organisms especially bifidobacteria and lactobacilli in the gut, reduce the incidence of respiratory infections commonly presenting with cough, cold, and fever and reduction of gut infections which causes diarrhea and other infections.
A diet enriched with prebiotics is one of the best ways to cement the immunity of children, especially infants. Mother’s milk is the best source of prebiotics for infants but if a mother is unable to breastfeed her child, a formula milk that is enriched with appropriate concentration and ratio of prebiotics may be taken in consultation with the pediatrician. To ensure that the child’s immunity isn’t compromised, a formula with GOS: FOS in 9:1 ratio helps since it mimics the prebiotic oligosaccharides present in breast milk.
(The writer is Clinical Director & Head – Neonatology, Apollo Cradle, Gurgaon.)