Granny Smith apples take a bite out of obesity

Granny Smith apples take a bite out of obesity

The old adage “An apple a day keeps the doctor away” may be getting an update. New research indicates that certain types of apples may help keep obesity at bay.

Researchers at Washington State University in Pullman revealed that non-digestible compounds found in Granny Smith apples may actually help stave off obesity-related disorders.

According to the study, published in the October edition of the journal Food Chemistry, the tart green apple encourages the growth of healthy colon bacteria. This growth occurs due to dietary fiber, antioxidants called polyphenols and the low content of available carbs found in Granny Smith’s non-digestible compounds.

The compounds remain intact even after being subject to stomach acid and digestive enzymes. When they reach the colon, fermentation occurs, which benefits friendly bacteria growth in the gut.

Compared to other apples including Braeburn, Fuji, Gala, Golden Delicious, McIntosh and Red Delicious, the Granny Smith apple far and away beat out the others in the amount of non-digestible compounds it contains.

Researchers hope this discovery could help prevent such obesity-related disorders as low-grade, chronic inflammation that can lead to diabetes.

The study’s lead researcher, food scientist Giuliana Noratto said in a statement that in obese people, bacterial communities in the colon are out of balance. This results in microbial byproducts that lead to inflammation and influence metabolic disorders linked to obesity.

“What determines the balance of bacteria in our colon is the food we consume,” added Noratto.

By re-establishing a healthy balance of colon bacteria, metabolic processes that affect inflammation as well as that sensation of feeling satisfied can be stabilized, said Noratto.

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  1. I try to eat apples often, but now I know it could matter what type of apple it is!

  2. Ahhhh, polyphenols — the same reason green tea is so good for you! I’m happy to have another reason to eat Granny Smiths: not just because they’re sweet-tart and delicious for making caramel apples but because they’re better than other apples. And this is such a good time of year to have a Granny Smith for dessert with a nice piece of sharp, well-aged cheddar instead of something sugary or junk food in general. Works for me! Note to the applesauce manufacturers: I used to be able to get big jars of no-sugar-added Granny Smith applesauce, and now the only way to get that is in those stupid, wasteful little prepackaged plastic kid-sized containers — that’s just SO wrong for so many reasons. Bring back the big glass jars and the Granny Smith sauce, please!!!

  3. Good to know, would the Granny Smith apple have the same effect re-establishing a healthy balance of colon bacteria served in an apple pie?

  4. That’s a great question, Marie. I’m not sure if all the other ingredients would lessen the effects of just a Granny Smith alone or not. I would imagine the apple by itself would be most effective. But it does justify having another piece of apple pie! 😉

  5. Granny Smith apples are so tasty- I enjoy them as a healthy snack with peanut butter!

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health enews Staff
health enews Staff

health enews staff is a group of experienced writers from our Advocate Aurora Health sites, which also includes freelance or intern writers.