Scientists at Washington State University have
concluded that non-digestible compounds in apples – specifically, Granny Smith
apples – may help prevent disorders associated with obesity.
Fight against obesity
The study, thought
to be the first to assess these compounds in apple cultivars grown in the
Pacific Northwest, appears in October’s print edition of the journal Food
“We know that, in general, apples are a good source of these
non-digestible compounds but there are differences in varieties,” said food
scientist Giuliana Noratto, the study’s lead researcher. “Results from this
study will help consumers to discriminate between apple varieties that can aid
in the fight against obesity.”
The tart green Granny Smith apples benefit the growth of friendly
bacteria in the colon due to their high content of non-digestible compounds,
including dietary fibre and polyphenols, and low content of available
Read: How apples keep the doctor away
Despite being subjected to chewing, stomach acid and digestive
enzymes, these compounds remain intact when they reach the colon. Once there,
they are fermented by bacteria in the colon, which benefits the growth of
friendly bacteria in the gut.
The study showed that Granny Smith apples surpass Braeburn, Fuji, Gala,
Golden Delicious, McIntosh and Red Delicious in the amount of non-digestible
compounds they contain.
Balance of bacterial communities disturbed
“The non-digestible compounds in the Granny Smith apples actually changed
the proportions of faecal bacteria from obese mice to be similar to that of lean
mice,” Noratto said.
The discovery could help prevent some of the disorders associated with
obesity such as low-grade, chronic inflammation that can lead to diabetes. The
balance of bacterial communities in the colon of obese people is disturbed.
This results in microbial byproducts that lead to inflammation and influence
metabolic disorders associated with obesity, Noratto said.
Read: Obesity thwarts appetite regulation
“What determines the balance of bacteria in our colon is the food we
consume,” she said.
Re-establishing a healthy balance of bacteria in the colon stabilizes
metabolic processes that influence inflammation and the sensation of feeling
satisfied, or satiety, she said.
The study was funded with an Emerging Research Issues Internal
Competitive Grant from the Agricultural Research Centre at Washington State
University’s College of Agricultural, Human and Natural Resource Sciences.
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Image: Granny Smith apples from Shutterstock
By Sylvia Kantor, College of
Agricultural, Human & Natural Resource SciencesSee breaking news and the hottest health tips before anybody else by joining South Africa’s biggest and best health community, like health24 on Facebook now!