Studies indicate that more than 90% of young people do not get enough fiber in their diet.

Fiber is a crucial nutrient for maintaining gut health, also referred to as gastrointestinal (G-I) health. Melissa Mendez, a registered dietitian at Parkland Health, explained to KERA’s Sam Baker how fiber supports the digestive system.

Mendez said the intestines contain trillions of healthy bacteria, or microbiota, which act like probiotics. “These live organisms need prebiotics - the food they eat. By consuming healthy fiber-rich foods, we provide what they need to protect our bodies and keep us healthy,” she explained.

When asked if fiber is the main food microbiota need, Mendez confirmed that it is, noting that there are two types: soluble and insoluble fiber.

Soluble fiber mixes with water to form a gel-like substance, feeding gut bacteria. Examples include oats, bananas, and the flesh of apples. Insoluble fiber, found in foods like celery, does not dissolve in water and helps bulk up stool, supporting bowel movements and clearing the intestines.

“Both types are important,” Mendez said. “Some foods, like spinach, pears, and apples with the skin, contain both soluble and insoluble fiber.”

She cautioned against drastically increasing fiber intake all at once. “If you suddenly go from zero fiber to a large amount, it can cause bloating and gas. Gradually add fiber daily or weekly to allow your body to adjust.”

Beyond fiber, probiotics also play a key role in gut health. Fermented foods like yogurt, kimchi, and sauerkraut introduce beneficial bacteria that support digestion and immunity while providing additional nutrients like calcium, vitamin D, and protein.

Regarding fiber supplements, Mendez advised against relying on them. “Supplements are generally reserved for hospital settings or specific medical conditions and are not regulated by the FDA. The label may not accurately reflect what’s in the pill, so it’s best to focus on natural food sources.”

In summary, a balanced diet rich in both types of fiber and fermented foods is the safest and most effective way to maintain a healthy gut.