8 Signs You’re Overdoing It With Fiber Supplements

Dietary fiber is a must for smooth digestion and overall health. But it can be easy to overdo it with fiber supplements, like gummies or powders. And that can cause some unpleasant side effects.

While there’s no such thing as a fiber overdose, drastically and quickly upping your fiber intake can cause gastrointestinal (GI) problems and other issues. That’s more likely to happen with supplements than with fiber from food sources, says Brooklyn-based nutrition expert Eling Tsai, MPH, RD, CDCES, especially if you’re munching fiber gummies like candy.

Here are eight signs you might be overdoing it.

1. You’re Gassy, Bloated, or Crampy

“Fiber has a sponge-like quality and attracts water, which explains bloating. It can also slow digestion to the point where cramps begin to occur as well,” Tsai explains.

These problems should ease up as your GI tract adjusts to the higher fiber dose. But if they persist, that could mean you’re taking a higher dose than you need.

2. You Feel Extra Full

“Fiber-rich foods tend to be more filling and naturally decrease appetite after a meal,” Tsai says.

3. You Have Diarrhea

Fiber pulls water into the intestines and makes stool bulkier, smoother, and easier to pass.

But getting too much fiber, whether from supplements or food, can potentially result in bowel movements that are loose or liquidy, Tsai explains.

4. You’re Constipated

Again, fiber can support healthy bowel movements by making stool bulkier and easier to pass.

5. You Feel Dehydrated

Your water needs increase when you consume more fiber. Add supplements to your diet without drinking extra liquid, and you could find yourself thirstier than usual.

Diarrhea can increase the risk of dehydration, too, Tsai points out. So if your fiber supplement is causing you to have loose stool, you’ll need to drink more to compensate.

6. You’re Nauseous or Vomiting

If you’re suddenly feeling queasy or start to vomit, your fiber supplement could be to blame.

“These are more serious symptoms, as they could indicate a blockage in your digestive tract,” Tsai says.

• Wheezing
• Chest or throat tightness
• Skin rash or itchiness
• Swelling of the mouth, face, lips, or tongue
• Trouble breathing

7. You Feel Weak, Shaky, or Low on Energy

Dietary fiber can help reduce blood sugar spikes, especially in people with diabetes or prediabetes.

“Since the body is unable to absorb and break down fiber, it prevents the spike in blood sugar levels that can happen with any other form of carbohydrates,” says Nagendra Gupta, MD, an internist and hospitalist with Texas Health in Westlake, Texas.

8. Your Meds Aren’t Working Like They Should

“Fiber transits the digestive system without being digested,” Dr. Gupta says. “The medication may get swept along with the fiber and get excreted without being fully absorbed.”

To prevent this problem, take your medications an hour or two before taking your fiber supplement.

What’s the Right Dose of Fiber Supplements?

If you’re considering trying a fiber supplement, the dose you take should help you meet the 28 to 34 grams per day recommended for adults. But it’s very important to add fiber to your diet slowly, allowing your body to acclimate and adjust.

“Fiber supplements generally range from 2 to 5 grams per serving, and some people may need up to two or three servings a day to improve their symptoms,” Tsai says.

That said, it’s a good idea to determine how much fiber you’re getting from food to figure out the right supplement dose for you.

How to Know if You Need Fiber Supplements

Experts recommend trying to meet your fiber needs through food first. But if you’re having trouble reaching your daily needs, talk with your doctor.

“Taking a fiber supplement can be a good way to fill the gap,” Gupta says. Your provider may also recommend taking a fiber supplement to manage high cholesterol.

Up your intake gradually if you decide to supplement, and only take the amount of fiber you need. “It’s very important to add supplementation slowly and hydrate appropriately,” Tsai says.

The Takeaway

• Fiber is beneficial for digestion and overall health, but abruptly increasing your intake, especially through supplements, can lead to uncomfortable side effects, such as gas, bloating, and cramping. It’s best to ramp up your fiber intake gradually with plenty of hydration to help your body adjust.
• Some fiber supplements can interfere with the absorption of medications. To avoid this issue, take your medications at least an hour or two before consuming any fiber supplements.
• Excessive fiber intake can cause serious symptoms, such as nausea and vomiting. If these occur, seek medical attention, as they may indicate a digestive tract issue.
• Determining how much fiber you get from food can help establish the right supplement dose to reach the recommended 28 to 34 grams per day for adults. Talk with your healthcare provider to ensure you’re using fiber supplements adequately and safely.