What Actually Happens If You Eat Too Much Fiber

Fiber is a nutrient people love to talk about because it has so many health benefits. This type of carbohydrate helps with digestion, gut health, cholesterol, and blood sugar control. Most people don't get enough fiber in their diets, which is why nutrition discussions always include talk of adding more fruits and vegetables, fiber-rich legumes like lima beans and chickpeas, and whole grains like oatmeal — or even a fiber supplement. But there is such a thing as too much fiber.

If you load up on fiber too quickly, your gut doesn't get a chance to adjust. The natural bacteria in your gut suddenly get a feast they weren't prepared for, and all the fermentation leads to a lot of gas. That causes side effects like bloating, stomach cramps, gas, and general discomfort. Another issue is taking in so much fiber you're crowding out other nutrients. You might unintentionally limit how much protein and healthy fat you're getting. At very high levels, too much fiber can also affect your ability to absorb magnesium, calcium, zinc, and iron.

The good news is that if you accidentally went all-in on fiber, you can make a few simple changes to feel better soon. It's best to see a doctor or registered dietitian, who can help you determine the right amount of fiber for you and the best way to move forward. In general, women over 50 need 21 grams, while women under 50 need 25 grams. Men over 50 need 30 grams and men under 50 need 38 grams. 

They'll probably start by advising you to sip water throughout the day to stay hydrated  and avoid constipation. They'll probably ask about your eating habits and schedule to ensure you're spreading your fiber intake throughout the day. It's better to eat reasonably high-fiber breakfasts, lunches, and dinners rather than consuming it all at once. They'll also want to make sure you're leaving room for other nutrients. Ultimately, it's possible you'll need to cut back your intake of fiber temporarily, then gradually increase it over a few weeks. This will give your gut time to adjust to a larger amount of the nutrient.

Some light movement may also be prescribed to help relieve the discomfort you're experiencing. That might involve some light cardio like walking or biking or beginner-friendly yoga poses to help ease bloating.