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One Major Effect Oatmeal Has on Your Gut, Says Dietitian

Feed your stomach right.
FACT CHECKED BY Kiersten Hickman

Oats have earned their long-standing reputation as one of America's favorite breakfast staples. They are affordable, easy to find, satisfying, and packed with nutrition. Oats are usually eaten as a recognizable warm cereal: oatmeal perhaps topped with brown sugar, cinnamon, and bananas, or blueberries and walnuts. Although oats have also been appearing in more and more products such as non-dairy milk, bread, smoothies, granola, and breakfast bars. Oats' real claim to fame, however, is its beneficial effect on our gut.

A major advantage of oats in human health is the fiber content. Oats are a tremendous source of "beta-glucan", a particular type of soluble fiber. Beta-glucan is one of only three fermentable soluble fibers (along with inulin and pectin) which has the power to improve the environment of our gut for colonies of healthy bacteria to thrive.

Two studies from the British Journal of Nutrition in 2014 and 2019 reported that whole grains, such as oats, may increase the diversity of the microbiota, such as encouraging more growth of the health-promoting probiotic of the genus Bifidobacterium. Short-chain fatty acids (SCFAs) are produced from these fermentable fibers and help the body absorb important minerals like calcium, iron, and magnesium.

The journal Nutrients explain that short-chain fatty acids go on to promote further gut integrity, exert anti-inflammatory effects, help improve immunity, and can inhibit the expression of harmful pathogens like Salmonella and E. coli.

oatmeal fruit

Hopefully, we have convinced you to begin or continue including oats in your eating pattern! Let's look at the common oat types you'll see at the grocery store and how they are different.

  • Steel-cut oats: Also known as coarse oats, pinhead oats, or Irish oats, these oats are made from cut oat groats (kernels) sliced into two or three pieces with a sharp metal (steel) blade. They cook faster than oat groats because water can more easily get absorbed into the smaller pieces.
  • Old-fashioned oats: These oats are also called rolled oats. They are made by steaming oat groats and rolling them into flakes, so they are flat and have a greater surface area.
  • Quick oats: This oat type is steamed longer and rolled thinner than old-fashioned oats.
  • Instant oats: These are the smallest or thinnest version of oats and absorb water and cook very quickly (usually just one to two minutes). Be sure to purchase instant oats that contain little to no added sugar.

For healthy oats recipes, here are the 51 Healthy Overnight Oats Recipes for Weight Loss.

Molly Hembree, MS, RD, LD
Molly Hembree, MS, RD, LD, is a nationally recognized registered dietitian. Read more about Molly