Postbiotics: An Ingredient to Watch
This past summer, researchers associated with Danone Nutricia, an infant formula company in the Netherlands, published an early-stage study using an experimental formula that contained postbiotics.
Photo by Pixabay
While nothing can replace human milk, manufacturers strive continuously to improve their product. All infants deserve the best nutrition. Improving infant formula has the potential to improve the health of the millions of infants nourished by it every day.
One influence on infant health is the collection of bacteria, both good and bad, which together are called the gut microbiota. Infants who drink infant formula have a different mixture of bacteria species in their microbiota than is found in breastfeed infants. In other words, the gut microbiota profile of a formula-fed infants is different than a breast-fed one.
While we are still learning about the health influence of the microbiota, science suggests that this difference matters for immune health and likely is a factor for why breast-fed infants have fewer illnesses than formula-fed infants. It may also be important for lifelong immune health.
Probiotics, Prebiotics, and Postbiotics
To understand why postbiotics are an ingredient to watch, it would help to review its relationship to two common ingredients, prebiotics, and probiotics. All three have relationship to the microbiota, which in turn, effects immune health.
Beneficial bacteria are the “good guys” of the microbiota. What makes them good? They help digest food that humans cannot and nutrients that happened to make it the large intestine without being absorbed. When beneficial bacteria feed, they make substances (compounds) that have a positive influence on human health. These beneficial bacteria are called probiotics. A few infant formulas contain probiotics, such as L reuteri and L rhamnosus GG.
On the other hand, most infant formulas contain prebiotics, which are a special class of fibers that humans are not able to digest. Passing through the digestive system untouched, they arrive in the large intestine. Give the “good guy” probiotics a lot of their favorite food and they flourish, leaving less room for bad guy bacteria to cause harm. Not only do they dominate the playing field of the gut, but well-fed probiotics also make compounds that directly benefit health. Galacto-oligosaccharide (GOS) and polydextrose (PDX) are prebiotics.
Postbiotics are the beneficial compounds that the probiotics make when they feed on the prebiotics. Postbiotics have specific health benefits, especially to the immune system. For example they seem to be able to improve an infant’s immune response to the polio vaccine through a natural antibody, secretory immunoglobulin A (SIgA).
“probiotics + prebiotics = postbiotics”
To sum these three terms up: Prebiotics are food for probiotics that then make postbiotics. The human immune system interacts with the microbiota through postbiotics. Dietary prebiotics (what we eat) can influence how many and which probiotics are present.
Postbiotics as Infant Formula Ingredient
The exploratory study mentioned previously, looked at what happened when infants were fed postbiotics in addition to the usual prebiotics found in formula. Just like explorers who venture into unknown areas, exploratory studies are used for issues that have not been studied much in the past. As a result, exploratory experiments cannot prove cause and effect (causality). But they can increase understanding of an issue, much like an explorer can map out a new location for another person to survey in detail in the future.
This exploratory study showed that the SIgA (antibody) was significantly higher in infants fed an experimental formula made with prebiotics and postbiotics compared to infants who drank formula with only prebiotics. And the microbiota profile of the babies getting the experimental formula looked more like that of breast-fed infants than the comparison formula made without postbiotics.
Why Postbiotics Are an Ingredient to Watch
Postbiotics are an interesting potential infant formula ingredient, because they could make it possible to mimic some of the microbiota metabolism and immune system changes that typically are only seen in fully breastfed infants. Naturally, infant formula is a substitute for human milk. It is not a true replacement. However, optimal nutrition is something every baby deserves.
Photo by Elvert Barnes on Flickr