EVERYWHERE YOU LOOK, people are telling you to get more fiber. “It keeps things moving!” and “it keeps you full!” say the TV doctors and supplement ads.
And, actually, they’re right. In fact, given that an estimated 95 percent of men in America aren’t hitting the daily recommended amount of dietary fiber, chances are you should be eating more of it. But, all fiber is not created equal. In fact, there are actually two types of nutrient.
“Soluble fiber helps improve our blood glucose (blood sugar) control and insoluble fiber helps regulate our bowel movements,” says Matthew Landry, P.h.D., R.D.N., assistant professor at the University of California, Irvine.
What do you need to know about insoluble versus soluble fiber? Below, dietitians explain how each of these types of fiber play an important role in our health.
What is fiber?
“Fiber is a zero-calorie non-digestible carbohydrate that has copious health benefits from regulating blood sugar and boosting heart health, to alleviating constipation and keeping you full and satiated,” says Lisa Moskovitz, R.D.
What’s the difference between insoluble and soluble fiber?
While all fiber is beneficial fiber, there are two distinct forms: soluble and insoluble, both of which are equally important to your health. Fundamentally, the difference between these two types of fibers relates to how the fiber reacts with water.
“Soluble fibers can dissolve in water and insoluble fibers do not dissolve in water,” says Landry. “In our intestines, soluble fiber dissolves into a gel. This gel can help slow the absorption of sugars in our diet (helps keep our blood glucose levels steady) and binds to cholesterol particles. Insoluble fibers pull water into our intestines, helping to make our stool softer and easier to pass.”
Soluble fiber acts like a sponge slowing down digesting which helps keep blood sugar levels stable, your stomach full and can even help lower cholesterol and boost gut health, says Moskovitz. Meanwhile, she compares insoluble fiber to a power wash for your GI tract.
“It’s specifically adept at promoting regular bowel movements, clearing out harmful substances and preventing colon cancer,” she says.
What are good sources of soluble and insoluble fiber?
It’s essential to consume a variety of fiber-rich foods in your diet to ensure you’re getting both fiber types. So, how can you get soluble and insoluble fiber? Our experts laid out a few sources of the nutrients, below. Note: there is some overlap between the two categories, as foods can contain both types of fiber.
Foods That Contain Soluble fiber
- Citrus fruits
- Barley
- Peas
Foods That Contain Insoluble Fiber
- Bran
- Brown rice
- Leafy greens
- Berries
- Whole-wheat pasta
Foods That Contain Both Insoluble and Soluble Fiber
- Avocados
- Black beans
- Kidney beans
- Pears
- Chia seeds
- Broccoli
- Sweet potatoes
- Figs
- Oats
- Brussels sprouts
- Apples (with the skin)
- Almonds
How much fiber should you get daily?
Odds are, you’re not getting enough of either type of fiber. You should make every effort to incorporate more of the nutrient into your daily routine.
“While the American Heart Association recommends men consume about 30 to 38 grams of total fiber per day, there is no limit unless you have certain GI issues that make it difficult to tolerate a higher fiber diet,” says Moskovitz. “Otherwise, a high-fiber diet (>35g per day), especially when comprised of a variety of plant-based foods, will only increase the amount of both soluble and insoluble fiber ingested and benefits derived.”
What about the breakdown for the amount of soluble and insoluble fiber you consume?
There’s no dietary reference intake for insoluble or soluble fiber, says Landry, but the consensus is that about a quarter of total fiber should be soluble.
“For men that’s about eight-to-10 grams coming from soluble fiber,” and the rest of our fiber intake should be insoluble, he says. ”Most men don’t meet the recommendation, or even come close to it. As a dietitian, I recommend men just try to get enough fiber in their diet without worrying too much about the type.”
That said, take caution. When adding fiber into your diet, do so gradually, and to make sure you’re drinking enough water to avoid any gastrointestinal discomfort.
