Yes, eating more fiber can help with weight loss and maintaining a healthy weight

Fiber is probably best known for its ability to prevent or relieve constipation, according to the Mayo Clinic, but they say foods that are high in fiber also provide several health benefits, like lowering a person’s risk of diabetes, heart disease and certain types of cancer. 

VERIFY viewer Melina wants to know what other health benefits eating more fiber can offer, like if it can help people lose weight. 

THE QUESTION

Does eating more fiber help with weight loss? 

THE SOURCES

• Mayo Clinic
• American Institute for Cancer Research
• Dr. Whitney Linsenmeyer, Registered dietitian, assistant professor of nutrition at St. Louis University and spokesperson for the Academy of Nutrition and Dietetics
• Study on fiber and weight loss published in the Annals of Internal Medicine

THE ANSWER

Yes, eating more fiber can help with weight loss and maintaining a healthy weight.

WHAT WE FOUND

Dr. Whitney Lisenmeyer, an assistant professor of nutrition at Saint Louis University who serves as a spokesperson for the Academy of Nutrition and Dietetics, told VERIFY it’s “absolutely true” that eating foods containing fiber can help a person lose weight and maintain a healthy weight.

“Fiber can help with weight loss or with just maintaining a healthy weight. There's tons of really good evidence to support that fiber does a lot of different things to our health. It helps us to feel fuller longer after eating a meal so that we're not hungry again two hours later after eating,” said Lisenmeyer. “It can really help with blood cholesterol levels for patients, well for everybody really, but especially for patients that might have diabetes or prediabetes. It can help with our cholesterol levels, too, so there’s lots of all-around whole body system benefits to eating fiber.” 

According to the American Institute for Cancer Research (AICR), fiber is a type of carbohydrate found in plant foods. There are two basic types of fiber, which are defined by how they react with water: insoluble fiber, which does not dissolve, and soluble fiber, which does. While both types of fiber provide health benefits, the AICR says soluble fiber, which is also referred to as viscous fiber, is typically the focus of weight research. 

“When viscous fiber mixes with water in our body it becomes a gel-like consistency and slows down digestion. That can help people feel full longer, which can help people eat less,” the AICR says on its website. It also mentions that AICR research has found that eating foods containing fiber can help people lose weight and can even protect against unwanted weight gain. 

When it comes to how much fiber a person should consume per day, the U.S. Department of Agriculture’s Dietary Guidelines for Americans says women should eat a minimum of 25 grams of fiber per day, while men should eat 38 grams per day. But Lisenmeyer says the average American consumes closer to 15 grams of fiber per day.

“Because of our kind of normal dietary patterns, most Americans are consuming well below the recommended amount of fiber,” said Lisenmeyer. “Some folks will use a fiber supplement, like a powder that could be added to water or different foods that have been fortified with fiber, like fiber bars or breakfast cereals with lots of added functional fibers to them, and those generally, are perfectly safe, but I would say it's also perfectly possible to get all of our fiber by not relying on a supplement and to consume those whole foods. So, the vegetables, fruits, whole grains, beans, legumes.” 

In a 2015 study published in the Annals of Internal Medicine, researchers evaluated a diet focused on increased fiber consumption to a diet based on the American Heart Association's multicomponent dietary guidelines. After 12 months, researchers found many of the adult participants in the high-fiber group lost around 4.5 pounds. Meanwhile, participants in the AHA diet group lost nearly 6 pounds. The researchers concluded that while the "more complex" AHA diet resulted in more weight loss, they determined "emphasizing only increased fiber intake may be a reasonable alternative for persons with difficulty adhering to more complicated diet regimens."

On the Mayo Clinic’s website, they share a list of ways people can fit more fiber into their diets. They also note that people should try to avoid adding too much fiber to their diet too soon. 

“High-fiber foods are good for your health. But adding too much fiber too quickly can promote intestinal gas, abdominal bloating and cramping. Increase fiber in your diet gradually over a few weeks. This allows the natural bacteria in your digestive system to adjust to the change,” according to the Mayo Clinic. “Also, drink plenty of water. Fiber works best when it absorbs water, making your stool soft and bulky.”

More from VERIFY: Yes, the food pyramid was an updated version of the USDA’s first visual food guide released during World War II