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The students learning how diet choices affect their microbiome

Auckland Girls’ Grammar students Vivian Falefoou, left, and Lu’isa Ma’asi. Photo/Rebekah Robinson/Listener

“People in our years are consuming fizzy drinks without knowing the risks. We need to open our eyes and realise the food we consume can threaten our health.”

It seems sensible to assume that if you’re a mal­absorber of fructose, it’s good for your health, but it’s likely to be a lot more complicated than that. Scientists don’t yet know, for example, if the non-absorbed sugars that are fermented in the gut cause their own adverse effects on the all-important microbiome.

Maurice Wilkins Centre deputy director Professor Peter Shepherd says it’s possible the research will discover that some people are avoiding sugar because, as with milk intolerance, it causes unpleasant gut symptoms. “This shows there really is some sort of biological difference in kids that is restricting their uptake of sugar now. As we move up to studying higher doses of fructose, we expect that differentiation to increase. Where that becomes important is how it affects kids’ ability to tolerate sugars. If you drink sugar and get a gut ache because you are not absorbing it and the bacteria are fermenting it, it will self-limit consumption.”

Macro alias: ModuleRenderer

When the Listener visits Auckland Girls’ Grammar in May, 30 students who’ve fasted for 12 hours are swallowing 250ml of a fructose-glucose solution and then measuring the amounts of hydrogen on their breath in 15-minute intervals – rising hydrogen levels are an indicator of malabsorption, indicating the sugars aren’t absorbed in the small intestine, but are being fermented by bacteria in the gut.

Year 10 students Vivian Falefoou, 14, and Lu’isa Ma’asi, 15, have discovered they’re both “absorbers” and already they’re looking to cut down the amount of sugar they eat. Both say they’ve got a sweet tooth and enjoy fizzy drinks and chocolate. “It’s very important work,” Lu’isa told the Listener. “People in our years are consuming fizzy drinks without knowing the risks. We need to open our eyes and realise the food we consume can threaten our health.”

Auckland Girls’ biology teacher Helen Webber took two years out of teaching to run the first sugar study in New Zealand school pupils when she tested absorption in 825 Year 9, 10 and 11 students, and published a thesis for her Master of Health Science degree last year. Shepherd says she is one of a group of teacher-scientists who can link schools, universities and research institutes.

Her study found that absorption status wasn’t correlated with BMI, gender, school location, exercise level, fruit or sugary-drink intake in most ethnicities, but there was a significant difference in the BMI of Pacific absorbers and malabsorbers, with those of the absorbers being much higher.

From Auckland north, Sugar in Schools is run by health-science graduate Conor Watene-O’Sullivan from a research centre in Kaitaia set up by the MWC and the Moko Foundation. South of Auckland it is headed by Waikato-based teacher-scientist Crystal Gerring.

Gerring, who teaches biology and chemistry at Cambridge High School, but is taking a year off to run the Maurice Wilkins programme, says it’s hard to gauge if students worry about their results. “I tell them we don’t actually know how it may affect them, because it’s early days for the research, but I tell them it’s important to know what they are because if they’re an absorber, it means they’re taking in all the sugar, which can be associated with a higher BMI. But if you’re not, it means the sugar is going through the bacteria in the intestine and it’s having a field day and it could cause problems with your physiological processes as well.”

Watene-O’Sullivan says his com­munity has been very open to the research. “Part of our job is to build scientific and research literacy in our communities to understand how beneficial they can be.” He originally went to university to study medicine, but diverted to health science when he didn’t get the necessary grades to continue the medical course unless he studied as a post-graduate. Now he thinks the change of career may be permanent.

“I’ve found I like delivering this sort of research in an alternative way and applying my skills in public health to create benefits other than just data collection. My plan was always to come back [to Kaitaia]. We are taking a strength-based approach – asking what we can do better. We have the ability to engage with students and maybe inspire and incentivise them to pursue a career in health or science and higher learning, which can do with improvement in the Far North.”

This article was first published in the June 29, 2019 issue of the New Zealand Listener.