🥦 The recommended daily intake of fiber is 25 grams for women and 38 grams for men, but….

…most people consume less than half that amount.

Even though fiber is not digestible and gives us no nutritional value on its own, it does serve as an important fuel source for the gut microbiome. 

🚶‍♀️We’ve evolved to depend on nutrients produced by our gut bacteria (like butyrate and other short-chain fatty acids), but without enough fiber?

Gut microbes don’t get the fuel they need🙁

A brand new study out of Duke University looked at whether fiber supplements could make up for a lack of dietary fiber to support the health of the microbiome. 

They tested 3 types of fermentable fiber supplements:

🔸 Inulin (NOW Foods) at 9g/d

🔸 Wheat dextrin (Benefiber) at 9g/d

🔸 Galactooligosaccharides (Bimuno) at 3.6g/d

Participants were separated into groups and given one type of fiber for a week followed by each of the other types, with a week between each type of fiber to reset. Here’s what they found:

➡️ Those who had been consuming the highest amount of dietary fiber before the study showed the least change in their microbiomes. 

➡️ Those consuming the lowest amount of dietary fiber before the study showed the greatest increase in butyrate with the supplements (regardless of which type)

➡️ Gut microbes responded to the increased fiber intake within a day, altering the population of bacteria and changing which genes they were using to digest food.

That’s pretty incredible. 

When the gut microbiome has the fiber it needs, it produces compounds that help to fight inflammation, gastrointestinal diseases, and even obesity. 

So, what does this study show us?

✅The gut microbiome will benefit from fiber that comes from food OR supplements—and the type of supplement may not matter. 

Reference

Holmes ZC, Villa MM, Durand HK et al. Microbiota responses to different prebiotics are conserved within individuals and associated with habitual fiber intake. Microbiome. 2022; 10: 114. [link]