Protein gets a lot of press. But fiber should be sharing the spotlight. If you don’t get enough fiber, your digestion may be sluggish and you’re missing out on fiber’s critical health benefits.
Fiber is an indigestible carbohydrate found in plant-based foods, such as:
- Fruits
- Legumes
- Nuts and seeds
- Vegetables
- Whole grains
Even though it’s found in so many foods, most adults get less than half the recommended daily amount of 25 grams of fiber for women and 38 grams for men. One study shows that only about 5% of Americans get the recommended amount of daily fiber. Possible reasons? Some people may avoid fiber because it’s a carbohydrate. Others may fill up on other foods, such as protein or processed food, and simply aren’t hungry.
“Sometimes, when we prioritize one food group, others may fall short,” says UCLA Health senior dietitian Christine Goukasian, MS, RDN. “Including all the food groups is important because each food group provides different vitamins and minerals.”
Fiber can also be a hard sell because increasing it too quickly can cause temporary digestive discomfort. But if you focus on the health benefits and learn how to increase fiber safely, you’ll be one step closer to balancing your diet.
Benefits of fiber
There are two types of dietary fiber. Both critically influence your gut health:
- Insoluble fiber, found in whole grains, nuts and vegetables, bulks up your stool and promotes regular bowel movements.
- Soluble fiber, found in oats, beans, legumes and fruits, forms a gel in your digestive tract that slows down digestion, keeping you feeling full for longer.
However, the benefits of fiber go beyond everyday digestive health. Fiber may also help protect you against several health conditions and issues, such as:
- Cardiovascular disease
- Chronic inflammation
- Colon cancer
- Digestive disorder flare-ups
- Gastrointestinal diseases
- Type 2 diabetes
“Working in clinical nutrition, I see many patients for weight management,” Goukasian says. “Fiber helps by increasing satiety and slowing down digestion, but increasing fiber gradually is critical.”
How to get fiber
The best way to get fiber is through food. Fiber supplements can help with your daily intake, but they should not be your primary source.
Some of the highest-fiber foods include:
- Grains: barley, quinoa, cereal, popcorn, bulgur
- Legumes: beans, peas, lentils
- Vegetables: artichokes, canned pumpkin, sweet potatoes, broccoli
- Fruit: guava, raspberries, blackberries, pears
- Nuts and seeds: pumpkin seeds, chia seeds, almonds
Consider reducing ultra-processed foods if you are trying to increase your dietary fiber. Research suggests an inverse relationship between ultra-processed food and fiber — people who eat more calories from ultra-processed foods tend to have the lowest fiber intake.
If you have a diagnosed digestive disorder, such as inflammatory bowel disease (IBD) or irritable bowel syndrome (IBS), speak with your primary care physician or gastroenterologist before making dietary changes.
Tips for increasing your fiber
Adding too much fiber, too quickly, to your diet can cause uncomfortable digestive symptoms, such as:
- Bloating
- Constipation
- Diarrhea
- Gas
- Stomach cramps
Having a plan in place can help you add the fiber your body needs while reducing symptoms.
Goukasian recommends:
1. Go slow
Building up your body’s fiber tolerance is like building muscle — a slow-and-steady approach is usually best.
“Your gut bacteria need to get used to an increased amount of fiber,” Goukasian says. “We don’t want to overwhelm it.”
Increase your fiber slowly. Goukasian recommends adding 5 grams of daily fiber every few days until you reach at least 25 grams daily.
“Don’t eat all your daily fiber at once,” Goukasian says. “Getting the full 25 grams at breakfast may allow you to check it off your list, but it won’t be good for your gut. Instead, spread those 25 grams throughout the day.”
2. Keep a food log
Digestive symptoms related to fiber can arise for many reasons, including the timing of your meals or issues with certain carbohydrates. Keeping a food diary can help you better understand what foods may be giving you the most trouble.
“Keeping a journal of exactly what you ate, the symptoms you experience and the timing of both can help you draw a connection,” Goukasian says. “It may be that only certain fiber sources are problematic or that you just need to change when you eat.”
3. Make simple food swaps
Eating a fiber-rich diet does not require a menu overhaul. Instead, look for ways to swap out low-fiber foods for high-fiber options. For example:
- Add nuts or seeds to your salad instead of croutons
- Change out your white bread for whole-grain bread
- Choose a pear or raspberries to have with your breakfast instead of an apple or banana
“Making small swaps makes fiber manageable,” Goukasian says. “Identify some high-fiber snacks, such as cut veggies, nuts or popcorn, to get fiber throughout the day.”
4. Get things moving with water and walking
Moving fiber through your digestive tract helps reduce the risk of constipation and gas. There are two surefire ways to do that:
- Walking, which stimulates the natural contractions in your digestive tract to keep food moving
- Water, which aids the movement of fiber through your digestive system
“Fiber will help you have regular bowel movements, but water is critical to the process,” Goukasian says. “If you aren’t properly hydrated with at least eight cups of fluid daily, you are going to have more issues.”
If you are already suffering from gas and bloating after eating too much fiber, gentle movement and yoga poses may help you find relief.
When to see a doctor for symptoms of too much fiber
Goukasian also recommends speaking with a medical professional if your reaction to increased fiber is severe or the symptoms don’t go away.
“If you are having severe symptoms, there may be an underlying issue,” she says. “But don’t avoid fiber just because it may initially be uncomfortable. Instead, focus on helping your gut to adjust little by little.”
