You May Need More "Average" Produce Than Superfoods In Your Diet, According To A GI

Superfoods have a good reputation for a reason, but too much of a good thing is not always a good thing. When it comes to eating a healthy diet, incorporating diverse nutrient sources—specifically fiber—is more important than sticking to one type of healthy food, according to gastroenterologist Will Bulsiewicz, M.D., MSCI.

Dietary fiber is critical for overall gut health, which can affect immune functioning, mental health, and more. One common misconception about fiber is that it goes into the mouth, through the intestine, and immediately leaves through the colon. You know—digestion. However, there's much more to it than that. 

While insoluble fiber may work that way, soluble fiber acts differently. When fiber gets to the colon, the microbes get into a feeding frenzy, Bulsiewicz explains. These microbes will then transform those fibers into short-chain fatty acids, called butyrate, acetate, and propionate. "These short-chain fatty acids, to me, are the definition of anti-inflammatory," he says. 

Every single plant also has its own unique kind of fiber, which will feed specific microbes in the colon. "These microbes are picky eaters," he says. "They only like the fiber from specific foods."

Meaning, one microbe may eat up the fiber from kale, but another may rely on fiber from tomatoes, onions, or other more "average" plant sources. "You can eat two pounds of kale, but that won't be a healthy diet for your microbiome," he says. A diverse diet of average foods is superior to a diet that overemphasizes one or two superfoods." 

Whether someone is following a vegan, paleo, keto, or other type of eating plan, the best way to support a healthy gut microbiome is to introduce more diverse plants into the diet.