Americans seem to want to take care of their guts. They just don’t seem as interested in feeding them.
That’s the picture emerging from a recent analysis of nearly 63,000 people: Americans are taking probiotic supplements to improve gut health, but not changing their diets.
The surge in popularity can make it tempting to think that a daily capsule is enough to take care of your gut. However, without a diet rich in fiber from fruits, vegetables, and other plant foods, “you’re not going to get that much help from a probiotic,” Maria Marco, a microbiologist and professor at the University of California–Davis, who was not involved in the study, told The Epoch Times.
Probiotics are “in addition to, not in place of, a healthy diet,” said Marco. Fiber and probiotics do two different jobs. Fiber feeds the microbes already living in your gut and supports the gut environment. A probiotic, by contrast, is different. “It’s like a living thing, a microbe that we eat,” she said. A probiotic supplement has less to work with without a fiber-rich diet and is unlikely to deliver its full benefits.
The Probiotic Boom Left Fiber Behind
Related Stories
Researchers tracked probiotic use using the National Health and Nutrition Examination Survey, a nationally representative survey that asks Americans about their health, diet, and supplement use, from 2009 to 2023.
Probiotic use stayed fairly flat from 2013 to 2014. Then it began climbing, rising 786 percent among people younger than 20 and 287 percent among adults. The rise occurred across demographic groups, suggesting it wasn’t confined to any one population. The increase coincided with landmark research and media attention showing the importance of gut microbiome health.
Researchers analyzed the diets of nearly 55,000 participants. Among people younger than 20, fiber intake barely increased, from 7.37 to 7.97 grams per 1,000 calories. Among adults, it actually dipped, from 8.52 to 8.26 grams. The study used 14 grams of fiber per 1,000 calories as a benchmark, meaning both groups were eating considerably less fiber than the official dietary standard.
People who took probiotics did eat somewhat more fiber than those who didn’t, but the gap was small, and even probiotic users fell well short of the target.
Are Supplements Becoming a Shortcut to Health?
The appeal is that supplements “can feel simple,” Vandana Sheth, a registered dietitian nutritionist who was not involved in the study, told The Epoch Times via email. “You buy it, take it; there’s no prep or effort involved, and you feel like you are doing something positive for your health.”
Changing the way you eat can be more complicated, Sheth said. Food is tied to habits, preferences, culture, family, budget, and enjoyment. A capsule takes seconds; changing what you eat means building new habits meal after meal.
This fits a much broader pattern. Among people taking probiotics in the recent study, the median number of supplements they took overall was four, compared with just one among nonprobiotic users.
What Food Can Do That a Probiotic Can’t
Gut health isn’t just about having the “right” microbes. What happens in the gut is connected to the rest of the body, including metabolism, mood, and behavior, Marco said. “If we can sneak in more probiotics and more fiber into our meals, then we’re going to be helping not only our gut but every organ in our body.”
Sheth recommends starting small: Add more variety, especially fiber-rich plant foods such as beans, lentils, vegetables, fruits, whole grains, nuts and seeds. Fermented foods such as yogurt labeled “live cultures,” kefir, and kimchi can be part of the mix, too, if you enjoy them.
Whole foods and supplements aren’t interchangeable, and the difference is structural, not just a matter of habit. Different foods bring different types of fiber, nutrients, and plant compounds. Probiotics, by contrast, contain specific strains of microorganisms. “The gut microbes are influenced by what we eat regularly, and probiotics are very strain-specific,” Sheth said.
Fermented foods fit in between. They can contain live microbes, but they also bring fiber and other compounds produced during fermentation. That’s part of why the research on fermented foods is harder to interpret. If a study finds a benefit from eating kimchi, Marco noted, researchers can’t necessarily say whether it came from the microbes, the fiber, or other components of the food. A probiotic strain, on the other hand, is studied for a specific health benefit.
If You Do Take a Probiotic
Look beyond the word “probiotic” on the label. The specific strain—and the reason you’re taking it—are what matter. The U.S. Probiotic Guide, recommended by Marco, matches products and strains that have been studied for specific health uses, whether that’s easing gastrointestinal symptoms, supporting immune function, or even helping with sleep, and summarizes the evidence behind them for clinical decision-making.
Sheth suggests thinking of supplements “as one of the tools in a toolbox, not as a replacement for food.” When considering one, she recommends asking:
-
Do I actually need it?
-
What do I hope it will accomplish?
-
Is there good evidence for it?
-
Is it safe with my medications or health conditions?
“Taking a supplement does not automatically mean you have adequately checked the gut health box,” Sheth said. A supplement can fill a gap. However, it can’t fill every gap. The rest of the picture is built meal by meal.
