GRAZ, Austria — How does the old saying go? “100 million bacteria a day will keep the doctor away?” Sounds about right. A new study reveals that a typical 240g apple contains around 100 million bacteria, mostly in the seeds and skin. While that may sound a bit off-putting at first, researchers say that when it comes to gut health, the more bacteria the better.
Additionally, researchers at the Graz University of Technology say that organic apples were found to contain even more diverse bacterial-goodness than conventional apples, potentially making them healthier, tastier, and better for the environment.
“The bacteria, fungi and viruses in our food transiently colonize our gut,” explains study senior author Professor Gabriele Berg in a release. “Cooking kills most of these, so raw fruit and veg are particularly important sources of gut microbes.”
Berg and her team set out to find the best fruit source for beneficial gut microbes, so they decided to set their sights on one of the most popular fruits all over the world: the apple.
“Eighty-three million apples were grown in 2018, and production continues to rise,” Berg says. “But while recent studies have mapped their fungal content, less is known about the bacteria in apples.”
Researchers analyzed and compared the bacteria levels in regular store-bought apples and organic ones. Each apple was broken down and analyzed piece by piece, i.e., stem, peel, seeds, etc.
Both types of apples displayed generally the same amount of bacteria — 100 million, mostly in the core of the apple. For example, if you remove the core, a typical apple’s bacteria count drops all the way to a measly 10 million.
However, the organic and processed apples differed when it come to variety of bacteria. Organic apples displayed much more diverse communities of bacteria than the regular samples. This is noteworthy because when it comes to gut health, diversity is even more important that quantity.
“Freshly harvested, organically managed apples harbor a significantly more diverse, more even and distinct bacterial community, compared to conventional ones,” Berg explains. “This variety and balance would be expected to limit overgrowth of any one species, and previous studies have reported a negative correlation between human pathogen abundance and microbiome diversity of fresh produce.”
Furthermore, organic apples only were shown to contain Lactobacilli, a fairly well known probiotic. Conventional apples on the other hand, contained bacteria known to harbor pathogens. The research team even say that organic apples contain much more of a specific bacteria,, known to enhance flavor quality in fruits.
These findings mesh well with another recent study that found fungal communities among organic apples were much more diverse compared to regular apples grown using pesticides.
Berg and her team say that one day microbiome information on fruits and vegetables may be as readily available as more traditional nutrition information.
The study is published in the scientific journal Frontiers in Microbiology.