How snacking and sugar are messing with your microbes
Is fasting good for your gut? Does the suburb you live in affect your immune system? Does a pet make you healthier? These are the questions a citizen science project in Melbourne is trying to answer. The exhibition Gut Feelings opened at Melbourne Museum last year and asked visitors to "spit for science" so their oral microbes could be put under the microscope. Almost 1,500 people gave a spit sample and filled out a questionnaire about their lifestyle including the food they ate, their pets, and where they lived. The museum has created an interactive map of Victoria showing the difference in microbial diversity by suburb. Senior curator Johanna Simkin said the experiment provided clues as to how our habits shape our health. "The idea behind the project was to see if there was a pattern," she said. "Are kombucha-swilling northside hipsters healthier than latte-sipping south-siders?" Stop the snacking, avoid the sugar Preliminary results from the samples have shown Melburnians need to stop snacking and start cutting down on added sugar. Previous Australian research has found the bacteria in our modern mouths are a lot less diverse than our ancestors, and that our oral health has declined with modern diets. The museum's project found Victorians who were eating large amounts of carbohydrates, like added sugar and refined flours, had lower microbe diversity. Almost 90 per cent of adults in the study reported not eating the recommended five serves of vegetables a day, and 30 per cent reported eating one or fewer serves a day. Refined carbohydrates also make our mouths more acidic which leads to cavities, and could explain why our ancestors had better oral health. Melbourne Dental School senior lecturer Samantha Byrne said tooth decay in Australian children was "a big problem" with a quarter of children starting school with untreated tooth decay. Dr Byrne said while the study was not trying to answer a question related to oral health, it was a step towards characterising what our microbial communities look like to see if there were any relationships between our diets and oral microbes. University of Melbourne senior research fellow Julian Simmons said increasing the time between meals also allowed microbes in our mouths and bodies to balance out. But he wasn't sure what the affect was of intermittent fasting on microbes. "It's complicated because you go through periods where you are not fasting and you might be eating regularly during those hours, which means there's no time for microbes to rebalance." Your flatmates matter There was a trend towards higher microbe diversity when participants shared their home with at least one other person. Dr Simkin said it was too early to tell whether you needed to live with people outside of your immediate family to enjoy the benefits. And so far, there is no evidence to suggest a significant difference between coffee and tea drinkers, or northsiders and southsiders. But Dr Simkin did suspect that suburbs in Melbourne with more green space would make a difference, which is in line with recent research from The Ecological Society of America, that found microbiomes in green spaces affect human health by modifying immune function. Dr Simmons said the next step was to take the study to regional and rural areas to give people outside cities a chance to learn about their microbes. "We also hope to seek funding to delve into the samples at an individual bacterial and functional level, which would allow us to identify specific groups of people with specific relationships between microbes and health, socio-economic status, access to the outdoors, and our diet. This will inform future studies and health programs," he said.
What's with Melbourne's allergies? Dr Simkin said plotting the microbes of a healthy population of people was rare and she hoped the results of the citizen science project could shed light on why Melbourne has become the allergy capital of the world. "Melburnians are this weird species of hyperallergic people. We have interesting weather patterns coupled with Western cleanliness. But no one has looked to see if we have a unique microbiome speaking to our immune systems," she said. "I wondered if Victorians deviated from an 'ideal' microbiome to give us more allergies, and if so, could it be linked to lifestyle choices like diet, pets, smoking, or even where you live in Victoria." She said the initial results showed Victorians have "big chunks" of the same genus of bacteria as other cities around the world which means we can rule out Victoria's oral microbiome as being "crazy different from all other humans on the planet". "It's more likely to be a combination of microbiome including hyper-cleanliness, diet, cultural factors, and our vitamin D levels." Microbes and the future of medicine While the researchers can only speak about the preliminary results of the study and are reluctant to draw any hard conclusions, they hope the large number of samples will inform future health strategies. Doherty Institute lead microbiome researcher Andre Mu said microbiome research from other cities around the world could not be used to help inform Australia's health because microbial health was so reactive to individual environments. "We see differences in gut microbiomes between individuals, but we start to see patterns emerge when we compare at larger scales such as at a population level," Dr Mu said. "Having local data will provide a better representation of what the Victorian microbiome looks like." Delving into that data and the context of how Victorians live could then help scientists figure out how specific microbes react and work with specific medications.
Article from ABC News