Henna-Maria Uusitupa
2,493,227 views • 10:40

Now, I know it might be easy to think that microbes are bad, especially for infants, but research has in fact proven the opposite. And the truth might be a little bit more complex, but it's actually way more interesting. It seems that we need microbes to be programmed for good health, but not just any microbes, we need the right combination. We succeed best with the little microbial bodies we have adapted to coexist with during evolution. And I guess it won't surprise you to learn that we start acquiring that right combination right at birth. Well, at least some of us do.

Babies born by C-section and babies born vaginally aren't the same when it comes to microbial start to life, and after birth there are countless different early life events and circumstances that further modulate the way the gut microbiota is developing, such as the medications that might be prescribed for the infant or the mother, number of pets and siblings in the family, as well as level of hygiene at home, and, in this case, it's actually better if it's not that perfectly clean all the time. And also nutrition, both mothers and infants. All of these events and circumstances play a huge role in the gut microbial development and that has a huge impact on the lifelong health of that baby.

And I'm not talking about small health implications here. I'm talking about the big stuff. Microbes we acquire or do not acquire affect our likelihood of developing diseases like obesity, diabetes and even some cancers.

Since many of these early life events I just listed are such that we cannot affect them, they are inevitable, for example C-sections have been invented to save lives, and they do that daily, and most medications are prescribed for a valid reason, especially for infants, and so on. That is why we have to learn how to protect the health of these babies after the occurrence of such early life events that might disrupt their gut microbiota development.

I work as a researcher and as a technical lead of an infant health platform, and the question I'm trying to find a solution to every day at work, and the same question I'm aiming to answer in this talk, is how can we make sure that all babies get the same shot at lifelong health, no matter how they're born or what early life events they encounter. Seems like a noble cause, right? Great. So let's figure this out.

To begin, remember how I said that we need the right combination of microbes? Well, to get that combination right, we need to receive those microbes that inhabit our bodies in a certain order. You can think of it like a colonization march. The very early microbes that inhabit our bodies first change the environment in the infant's gut so that the next microbes are able to move in, kind of like the first invaders come in first and set up the infrastructure for the other settlers to build upon.

Now, if babies are born via C-section, that early phase of colonization is greatly altered, because instead of vaginal, fecal and skin bacteria of the mother, mainly only skin bacteria enter the infant gut. And that sets that colonization march to a totally different tone, and simply because that's different to what we've adapted to during evolution, that might cause some health disadvantages for C-section-born babies later on. We can take weight development as an example here. It has been already shown in several studies that gut microbiota composition is associated to weight as well as the likelihood of developing diseases like diabetes or cardiovascular diseases. But now there are some indications that you could already at infancy see from a fecal sample of a baby some microbes missing from those individuals who will later on develop to be obese or overweight. It has also been shown that those same microbes might be missing from babies who are born by C-section or who are predisposed to heavy loads of antibiotics in early life. And to kind of close this loop, it has also been shown in some research that babies born by C-section or are prescribed with many, many antibiotics early in life are more likely to be obese or overweight, even by 50 percent, which is a lot.

Now, I know you might be thinking at this point that, oh no, I just had a C-section or I was born via C-section or my child had the antibiotics. But I want you to not worry. If these microbes are missing or are lost for any reason, they can be acquired later, but the baby just needs a little help with that.

One thing that has already for some time been known to help is breastfeeding. Breast milk is kind of miraculous: in addition to containing nutrients for the baby, it seems to contain food for the good microbes as well.

That's great for a breastfed baby, but we all know that all babies are not breastfed. So what could we do to ensure that also those babies who are not breastfed could restore their microbiota development after encountering those disruptive early life events that might disrupt their gut microbiota development?

And now we get to the actual solution part of this talk. The research in this field has been taking giant steps lately. First, it was understood that if there are some microbes missing, they can be ingested. We call the good microbes, when they are ingested, probiotics, and probiotics have been tested in several clinical trials during the years, also in infants, with great effects, such as reducing their risk of eczema later in life.

Now, a second revolution was realized when the eyes of researchers were turned to breast milk. That was logical, as, like I mentioned, it was already known that breastfeeding is able to support the healthy development of gut microbiota. There were these particles in breast milk that were found already in the 1930s called human milk oligosaccharides, but their function remained a mystery for decades and decades after their initial discovery. They were really puzzling for researchers, as they are really abundant in human milk. They are actually the third-largest group of solids, but they are not digestible by humans, not even infants. So why would mothers synthesize something to breast milk, use their resources to put something there that is not utilizable by the infant? Usually nature does not work that way. Right? So it was quite a revelation when it was finally understood what's the role of these particles, and that it is to selectively feed the microbes that are best for infants, and that way to affect the infant health.

There are over a hundred of different HMO structures, and nowadays we are able to synthesize some of them also in the lab, and that enables us to package them up with probiotics for children and infants who are not able to receive them from breast milk to restore their microbiota after encountering disruptive early life events.

And that is the solution. As a researcher, I must say at this point that research in this field is still ongoing and a lot of work remains to be done. That's a favorite sentence of us scientists. But we are taking steps towards understanding better and better which are the key missing microbes in various situations and what HMOs we should package with which probiotics to help restore the microbiota of that particular baby in that particular case.

What I wish you to remember from this talk is that, yes, vaginally born breastfed baby has the microbiota we have evolved to adapt to, but in cases where that is not possible, there are means to reduce the negative health consequences.

Lastly, I wish you to imagine a world for a while, a world where there would be such a health care system that when you take your baby to a health care check, they would routinely monitor the gut microbiota development of that baby, and if any disruptions would be noted, a tailor-made product to restore the microbiota would be prescribed. I mean, how wonderful would that be, if the onset of any chronic diseases would be extremely rare because of this preemptive health care system? Can you imagine such a world? Do you believe that that kind of future would be possible?

I do. I believe in that future and I want to contribute in the unfolding of that future, a future in which each baby has an equal starting point for life to be programmed for lifelong health.

Thank you.