Benefit your digestion including helping you go to the toilet regularly. Soluble fibers, such as those present in oats, barley, nuts, seeds, beans, turn into a gel-like substance in your gut. This helps soften the stool, making it easier to pass, and to slow down digestion. Insoluble fiber present in whole grains such as brown rice, wheat bran, and quinoa and leafy greens interacts with the lining of your intestine, causing water and mucus to enter the colon and promote movement. Van der Schoot et al. 2022, de Wit et al. 2019.

Reduce your risk of chronic disease. For example:

Help with gut health. Fiber feeds your gut microbiome — the trillions of microorganisms that live in your gut. Boosting your gut bacteria with fiber helps explain some of the health benefits of a fiber-rich diet. A 2-week clinical trial with human participants showed that switching to a high-fiber diet significantly increased the participants' good bacteria. Additional publications include So et al. 2018, Cronin et al. 2021.

Improve blood sugar control. Fiber can help your blood sugar levels rise more gradually. During digestion, soluble fiber dissolves in water, creating a gel that slows digestion and allows the sugars in your food to enter your bloodstream at a slower pace. Goff et al. 2018, Nilsson et al. 2008.

Lower cholesterol. A fiber-rich diet lowers cholesterol in a few different ways. For instance, soluble fiber traps cholesterol in the gut. This prevents it from being absorbed back into the blood. Instead, it leaves your body in poop. Also, fiber feeds the “good” bugs in your gut. As the bacteria break down fiber, they produce short-chain fatty acids (SCFAs). These fatty acids reduce cholesterol production in the liver, lowering blood cholesterol levels. Fu et al. 2022, Jovanovski et al. 2018.

Help with weight control. When consumed, fiber absorbs water and expands in the stomach, occupying more space, which contributes to the sensation of fullness. Fiber takes longer to be digested which allows food to remain in the stomach longer, prolonging satiety. Foods that are high in fiber typically increase the chewing process stimulating saliva and gastric juices that help you feel full and slower eating rates give time to the brain to process satiety signals. Fiber helps reduces blood sugar spikes which are associated with increased feelings of hunger. A fiber rich diet stimulates the release of hormones responsible for the sensation of fullness, such as peptide YY, glucagon-like peptide-1 (GLP-1), and cholecystokinin (CCK). Karl et al. 2017, Kim et al. 2016, Clark et al. 2013.