Surprising Side Effects of Eating Too Much Fiber, Say Dietitians

Fiber is necessary for a variety of health reasons, but too much can cause a lot of discomfort.There's always the risk of having too much of a good thing. Protein, for example, is an important ingredient to consume on a regular basis, but too much of it can cause cognitive fog, bloating, and weight gain. Vitamin D, for example, has been linked to irritation, tiredness, and nausea.

This rule applies to fiber as well. Fiber is essential for a healthy digestive system, as well as a healthy heart, gut microbiome, and weight, blood pressure, and cholesterol management. But what if you consume too much fiber? We spoke with a few nutritionists to understand more about the risks of consuming too much fiber on a regular basis.

Then read Popular Foods with More Fiber Than Oatmeal for more healthy eating ideas.

How much fiber is too much?

Fiber is an important part of any diet that can aid with overall health. People that live the longest eat a lot of fiber on a regular basis all over the world, yet many people in the United States don't receive nearly enough.

"While optimal fiber consumption has been linked to gut health and has been demonstrated to help reduce disease risk, studies reveal that only approximately 5% of Americans fulfill their daily fiber need," says Kristi Ruth, RD, LDN of Carrots & Cookies.

So, how much fiber should you consume on a daily basis? "Women are urged to consume 21 to 25 grams of fiber per day, while males are encouraged to ingest 30 to 38 grams per day," says Trista Best, MPH, RD, LD of Balance One Supplements.

1 You may become more constipated as a result of this.

It may come as a shock, but eating too much fiber can cause constipation. Contrary to popular belief, you can develop constipated if you don't eat enough fiber!

"Many people try to increase their soluble fiber consumption in order to decrease cholesterol and/or enhance blood sugar control," Ruth explains. "They have no idea that increasing soluble fiber intake can cause constipation, especially if they are not drinking enough water. Those who start increasing their fiber intake to aid with constipation are likely to be surprised by this. Fiber and water combine to bulk up feces and aid in its passage through the digestive tract. Stools will form without water, but they will be difficult to pass. Finally, increasing your fiber consumption should be accompanied by an increase in hydration intake. Or, at the absolute least, make sure you're getting enough water each day."

2 It can, however, cause diarrhea.

While fiber is supposed to help you go to the bathroom, too much of it might cause constipation or diarrhea. A lot of it, according to dietitians, has to do with not only how much you eat, but also the type of food you eat.

"Intriguingly, if you increase your fiber intake too soon, you might get diarrhea," Ruth explains. "This is due to the fact that fiber (especially insoluble fiber) softens stool and has a laxative effect. Finally, understand the different forms of fiber and why you're increasing them. Consider gradually increasing your fiber intake to allow your digestive system to acclimatize. Finally, make an effort to achieve a decent balance of soluble and insoluble fiber."

3 You may suffer gas or bloating, which is unpleasant.

Ingesting too much fiber can swiftly derail your day by causing severe stomach discomfort.

"Eating too much fiber too rapidly might cause bloating or gas," explains Paulina Lee, MSHS, RD, LD, functional dietitian and founder of Savvy Stummy. "It's natural for our gut bacteria to produce some gas as it digests the food and fibers we eat," she says, "but if the gas and bloating become unbearable, you might want to reconsider your fiber intake."