In 2026, feed your microbiome what it deserves

If the festive season and holidays have left your gut in a mess, perhaps it’s time to pay some attention to your microbiome.

You may have heard that word, but what is the microbiome and why is it so important?

Professor Justin O’Sullivan, director of the Liggins Institute, took two minutes to explain the essence of the microbiome for our ‘Expert Tips in 2 Minutes’ series.

"Your microbiome are the organisms that live on all of your body’s surfaces. They live in your gut. They are bacteria, phages that attack bacteria, eukaryotic cells and a whole lot of organisms.

“They affect your health, your well-being and your development.”

O’Sullivan has been studying the microbiome and its importance for many years, but extracting the raw data needed for that research wouldn’t be everyone’s cup of tea.

“The way we look at the microbiome is very simple. We take your stool, your poo, we extract DNA from it, and we sequence that DNA. And, when we do that, we see the DNA of all the organisms that live in your gut.”

He says University of Auckland researchers know a fair bit now about how the bacteria in people’s gut affect health and well-being, including in those with metabolic syndrome, the likes of obesity, diabetes, lipedema and insulin resistance.

“We can identify how particular bacteria are associated with and change metabolic syndrome.

“But the bacteria can also affect your brain and your cognitive activities,” he says. “They do that by changing the amount of tryptophan you have or changing the amount of serotonin that can be produced from tryptophan.”

O’Sullivan says we’ve known for some time that modern life has upset our microbiome."

"But we can restore our microbiome in different ways. The simplest way is diet. You want to eat diverse numbers of plants, so different types of plants, seeds, nuts – and probably fewer burgers!"

O’Sullivan says some of the science being gleaned today builds on ancient practices and knowledge.

“Every generation likes to think they’ve thought of something new. But, for example, the Chinese in about the 4th century started making yellow soup to treat cholera, and that was a faecal microbiome transfer. They were using that to treat the microbiome."

And, in the early 1900s, Russian scientist Elie Metchnikoff came up with the idea of probiotics, treating the intestinal microbiome with Lactobacillus the friendly bacteria found in yoghurt. His core ideas about the importance of the gut microbiome have been validated by modern science. Metchnikoff also pointed to the Western diet as being problematic.

These days people often get information on the next best health solution from social media, including advertisements for products that have a positive impact on the microbiome. Can any of these products work?

“The short answer is there's not a lot of evidence that indicates they do,” says O’Sullivan. “The longer answer is there are numerous studies under way to identify new organisms that we believe will have a significant impact as long as we deliver them the right way and as long as it's for the right condition.”

But there's also a placebo effect.

“If it works and you feel good, then it's a good thing. But really, all you have to do is diversify your diet.”