Breast milk is the gold standard as far as nutritional recommendations go. It contains everything your child needs for optimal development in both growth and immunity.
But what exactly is it about breast milk that makes it so unique? Research suggests that the immune-nourishing benefit of breast milk lies in a special group of prebiotics known called milk oligosaccharides, with 2-fucosyllactose (2’-FL) as the best studied among them. This prebiotic was found to feed good bacteria in the gut, where about 70 per cent of the immune system exists.
The good news is, significant advancements in the field of nutrition have now made it possible, for the first time, to add this special prebiotic to milk formula. We checked in with our expert, Dr Mark Underwood, chief of neonatology and professor of paediatrics at the University of California Davis, who tells us more.
How was 2'-FL Discovered and What Does it Do?
According to Dr Underwood, scientists have always been interested in what makes breast milk so good for babies. In studying milk samples, scientists found that one very simple molecule – 2'-FL, a milk oligosaccharide – was abundant in breast milk. He adds, “Over time, it became clear that there weren't just two, or three, or 10 but over a hundred different kinds of milk oligosaccharides in mum's milk. However, milk 2'-FL happened to be very abundant in the milk of a large sampling of women." Scientists then found that all mammals – not just humans and other primates – have milk oligosaccharides in their milk. "Human mums make more complicated structures and larger amounts of milk oligosaccharides than any other mammal; the amount of milk oligosaccharides is huge! That implies that it must be very important since mums are expending all this energy to make these complicated sugar molecules."
The interesting thing about milk oligosaccharides – and this has only been discovered in the last five years – is that only a few select types of healthy bacteria in the babies' intestines are able to consume these milk oligosaccharides. "This has helped us begin to understand that those sugar molecules feed a very few healthy bacteria. Most of the other bacteria that live in our intestines cannot use these milk oligosaccharides as a food source. It's like the mum is saying to her baby, 'I want you to have more of these good bacteria in your intestines, so I'm going to put these sugar molecules in my milk'". This plays a very important role in the health of young children. As according to Dr Underwood, 70 per cent of the immune system is in the gut, so maintaining a healthy environment for gut microbiota to develop is crucial in helping babies build strong digestive and immune systems.
Research on 2'-FL has recently found that it has two distinct functions. Dr Underwood says, "Firstly, as a highly selective type of prebiotic, 2'-FL specifically stimulates the growth of good bacteria, giving them an advantage over all the other bacteria found in the intestinal tract. 2'-FL is also linked to an increase in the production of healthy substances such as short-chain fatty acids, and this helps the gut and immune systems to mature."
"The second function is that milk oligosaccharides act as a decoy by binding pathogens – the disease-causing organisms – found within the walls of the gut, preventing bacteria from sticking to the epithelial cells in the small intestine and colon. Increased levels of milk oligosaccharides in a mother’s milk are associated with decreased incidence of both gastrointestinal infections and upper respiratory infections in young children."
What's perhaps most exciting from all of this research is that scientists have figured out how to synthesise an exact copy of 2'-FL. And the good news is, it can now be added to formula to benefit more babies.
In the last decade, scientists have discovered that the first couple of years of a baby's life are the most important time for his or her developing immune system.
Dr Underwood emphasises, "There's a unique window of opportunity for the immune system to grow. From the time a baby is born, until we start introducing solid foods, that is when the most rapid development of the immune system happens, so that seems to be the most time to give healthy bacteria a chance to grow."
"I think there's growing evidence that suggests that negative changes in the intestines of our babies in the first six to 12 months of life predispose them to developing diseases such as diabetes, asthma, Cohn's disease, celiac disease etc., as they become children or adults," he adds.
Further, Dr Underwood highlights one other exciting area of research: the recent discovery that 2'-FL is also protective against a type of disease called necrotizing enterocolitis (NEC) which can destroy the intestinal wall.
"Premature babies are at high risk to get NEC, and we have come to understand that breast milk decreases a premature baby's risk of getting this disease. NEC affects within five and ten per cent of very premature babies and a good portion of them unfortunately do not survive. Those who survive often have damaged intestines and long term problems, so it is really exciting to know that 2'-FL is protective against NEC," he says.
In March this year, 2'-FL was approved for use in formula milk in Singapore, and these products became available in the supermarkets. For mums who are unable to breastfeed, this provides an interesting alternative worth looking into.
Are These New Formulas Really as Good as Breast Milk?
When asked if these formulas could provide identical benefits to breast milk, Dr Underwood said, "I don't think we should make direct comparisons. Remember that breast milk is extremely complicated. Breast milk has a lot of molecules in it that provide incredible protection to babies, and we are still discovering these things, so should not make a comparison."
"As much as possible, babies should have their mother's milk naturally, but if for whatever reason that cannot happen, formula may be the best alternative. The idea of adding something like 2'-FL to formula is an attempt to make it the best it can be."