5 Telltale Signs You've Had Too Much Fiber + What To Do About It
Dietary fiber is essential for maintaining good digestion, regular bowel movements, and satiety (i.e., feeling full), and yet, 95% of Americans1 don't get enough fiber in their diets. If you're someone who isn't meeting their daily dietary fiber needs (and statistically speaking, you probably are), you may be wondering how much you need to add to your diet—and how much fiber is too much.
Here's what you need to know about fiber, plus how to meet your goals (and not dramatically exceed them).
Can you take too much fiber?
Yes, it's possible to have too much fiber. However, the exact amount that qualifies as "too much" varies from person to person.
The National Academies2 recommends that women under 50 have at least 25 to 28 grams of fiber per day, while men under 50 should strive for at least 38 grams daily. The intake recommendations also decrease slightly for individuals 51 and up.
The National Academies hasn't established an upper tolerable limit for this essential nutrient (i.e., we must consume it daily because our bodies cannot synthesize fiber), as the consequences of having "too much" fiber are individualized and varied. In terms of safety, there isn't evidence that suggests a certain amount results in serious side effects.
"The amount of fiber each individual can tolerate without any negative side effects may totally differ," says Keri Gans, RDN, a New York City–based dietitian and author of The Small Change Diet. "What might work for one person may not for another based on their digestive system, age, and other factors."
Signs of too much fiber.
There are a few signs that can clue you in that you might have had too much fiber (especially in a short period of time and if you haven't routinely consumed much fiber before).
"When you have too much fiber, it can sometimes contribute to digestive upset," says Jessica Cording, M.S., R.D., CDN, a registered dietitian, health coach, and author of The Little Book of Game Changers. It's important to have enough fiber to have regular bowel movements, but too much fiber can make some people feel backed up, she says.
The opposite can also happen: "For some individuals, too much fiber will cause loose stools," Gans says.
Gas and bloating are also common signs of too much fiber intake, Cording says. "It can even reduce absorption of different nutrients if you've been having too much fiber for a long period of time," she explains.
Recommended fiber dose.
Again, the right fiber dose depends on a few factors—like how old you are, your biological sex, and your personalized health needs. "It really depends on the person," Cording says. "Everybody's body is different in terms of what they can tolerate."
And while you may experience less-than-desirable effects of increased fiber if you up your daily intake drastically (it's better to ease into fiber additions), it's worth noting that most Americans are far more likely to miss the mark on their recommended dosage. In fact, a 2017 scientific review published in the American Journal of Lifestyle Medicine3 found that the average American only eats about 16 grams of fiber a day—less than the recommended amount for a 1- to 3-year-old.
In general, Cording says it's very rare that she recommends people have more than 40 grams of fiber a day. Still, some people may be able to tolerate 50 grams of fiber without any issues, Gans says—but beyond that is really pushing it. For example, "100 grams per day is definitely a lot of fiber, and I would guess that, for the majority of people, it would be too much for their bodies to digest on a daily basis," Gans explains.
If you're concerned you're not getting enough fiber in your diet, Cording suggests "making it a point to incorporate one high-fiber food into each meal." That includes wonderfully colorful plants like leafy greens (spinach, Swiss chard, collard greens), cruciferous vegetables (kale, broccoli, Brussels sprouts, cauliflower), carrots, raspberries, apples, pears, whole grains, beans, lentils, or avocados.
"If you find it hard to meet your needs through food (maybe those are foods that you don't really like that much, or they don't fit into your day-to-day routine), fiber supplements can be useful," Cording says. "Supplements can also be useful if you find your needs have increased for whatever reason—like you're dealing with irregularity that's backing you up."
If you decide to leverage a high-quality fiber supplement to meet your daily fiber goals, consider mindbodygreen's organic fiber potency+. It offers 6 grams of soluble, insoluble, and prebiotic fiber in each scoop from advanced fiber sources (organic guar bean, organic kiwifruit, and a trio of organic mushrooms) to promote satiety4, regularity5, holistic gut health, and more.*
What to do if you have too much fiber.
If you have too much fiber, Gans says you shouldn't panic. However, you might have some unwanted gastrointestinal side effects, like gas and bloating. "If you are experiencing negative side effects, try drinking plenty of water and eating bland foods—such as white rice, chicken, eggs, and white toast—until you feel better," she says.
Cording also recommends upping your water intake. "Know that it will get better," she says. "But if you're really uncomfortable, limit foods that are hard to digest for the rest of the day, or until you feel better."
Benefits of fiber.
There are plenty of perks to making sure you have enough fiber in your diet. Fiber can promote good gut health, balanced blood sugar levels, and satiety, among other benefits:
Keeps you regular.
Research—including a 2020 narrative review of meta-analyses from the Journal of Chiropractic Medicine—has found that fiber supplementation is important to support regular bowel movements, along with gut motility.*
"Fiber helps build stool bulk and speed up transit time," Cording explains. Meaning, it helps keep things moving along in your GI tract.
Supports healthy immune function.
Fiber helps support the immune system, primarily in the gut, but that benefits the entire body. According to a 2021 review, fiber helps promote the function of short-chain fatty acids as it ferments in the gut, strengthening the gut barrier6 in the process.*
Up to 80% of your immune cells7 are in your GI tract, per a 2021 Nutrients review, and prebiotic fibers (along with probiotics) help sustain a healthy gut-immune function by promoting the integrity of the gut lining and supporting the diversity of your gut microbiome.*
Stabilizes blood sugar.
"Fiber has a way of slowing down the digestive process that can help buffer the breakdown of carbohydrates in food,"* Cording says. When carbohydrates in your body break down more slowly, you're less likely to get blood sugar spikes, she explains.
Helps you feel full.
Fiber makes you feel full in a few ways: "When it interacts with water, it takes up space in the stomach and can help you feel full for longer,"* Cording says. Fiber also "digests more slowly in our bodies, therefore aiding in satiety," Gans adds.
What will too much fiber do to your poop?
It depends. In some people, it can slow down gut motility and cause things to feel backed up. In others, it may do the opposite and contribute to loose stools. Consider your overall gut health and how much fiber you eat per day compared to the recommended daily intake to determine if you need more or less fiber to support healthy digestion and bowel movements.
How much is too much fiber per day?
The National Academies recommends that women under 50 have at least 25 to 28 grams of fiber per day; men under 50 should aim for at least 38 grams daily.
Depending on their baseline gut health and how much fiber their body is used to, some individuals can safely consume 40 grams or higher daily without having side effects. In general, it's best to increase your fiber intake slowly, drink plenty of water, and pay attention to your body in the process.
Fiber is an important part of a healthy diet, but it is possible to overdo it. That said, the vast majority of people are failing to meet their recommended daily dose of fiber, so it's far more likely your daily intake is missing the mark.
If you're falling short of meeting your fiber goals, try to add more fiber-rich foods (and consider a high-quality fiber supplement, like mindbodygreen's organic fiber potency+) to your diet to ensure you're getting enough of this critical complex carb.
Korin Miller is a freelance writer specializing in general wellness, relationships, and lifestyle trends with a master’s degree from American University. Her work has appeared in Women’s Health, Prevention, Self, Glamour, and more. She lives by the beach, and hopes to own a taco truck one day.