Fiber is an essential nutrient that we all should be getting more of in our diet—but here’s the problem: we just don’t. In the United States, adult women and men need 25 to 38 grams of fiber daily. But on average, most Americans get only 16 to 17 grams of fiber daily.[1] Recent research describes that fewer than one in ten U.S. adults meet their daily recommendations for fiber intake.[2] 

Are we doing any better across the globe? In Europe, a publication described that total fiber intakes are higher than in North America, with total intakes ranging from 15 to 25 grams per day in adult men and 14 to 21 grams per day in adult women. A little bit better! But collectively, we are still falling short.[3] 

Scientific experts and registered dietitians agree that most people fall short of their daily fiber intake, often referring to this shortfall as the fiber gap. We’re clearly struggling to get enough, and the question is…why? And why should you care?

Why Is There a Fiber Gap?

Food contains a matrix of nutrients, and fiber is just one. Fiber occurs naturally in various fruits, vegetables, legumes, and whole grains. You may also find fibers isolated or extracted from plant sources and added to foods, beverages, and dietary supplements. Not all fibers are the same, and there are key differences between soluble and insoluble fibers. Therefore, it might be challenging to identify what fiber(s) you are consuming from these various foods and how much you’re consuming. In other words, a big reason for the fiber gap is that you might not know what foods contain fiber and if those foods are giving you enough fiber. 

When it comes to “enough fiber,” many of us typically fall short simply because we need to consume many high-fiber foods to meet our recommended fiber intake.[4]  Most foods don’t contain an abundance of fiber in a typical portion or serving. For example, a medium apple with skin only contains around 4g of fiber. That’s why it’s helpful to incorporate fiber at every meal and snack to ensure you’re getting enough. It requires some planning to hit that 25 to 38 grams per day recommendation!

Why Worry About the Fiber Gap?

So, it’s hard to get enough fiber daily, but why should you care about fiber in the first place? Well, fiber plays a crucial role in your overall health. It supports your intestinal regularity and provides nourishment for bacteria that live in your large intestine. It may also help slow the absorption of sugar. This means it could help support healthy blood sugar and cholesterol levels, among other potential heart-health benefits.[5]

As for those bacteria, trillions of microorganisms collectively form your microbiome, or gut microbiota. The different species and types of bacteria are known as microbiome diversity. The good bacteria need food to survive, which is where fiber steps in. Your gut is like a brewery where fiber ferments to serve up a variety of health benefits. More fiber means more healthy bugs to help your body work at its best! As your gut enjoys fiber, it creates metabolites that may support better immune system function, among other health benefits.

Here’s the situation, though: For years, dietary fiber has been recognized as a nutrient of public health concern. The 2020-2025 Dietary Guidelines for Americans highlight that low intakes of fiber and other vital nutrients like calcium, vitamin D, and potassium are linked to health concerns.[6]

What Happens if You Don’t Eat Enough Fiber?

Not eating enough fiber may lead to occasional GI problems, such as occasional constipation and irregular bowel movements, as fiber helps keep things moving smoothly. It also plays a role in keeping you full, so a low-fiber diet may not keep you as satisfied and leaves room for eating extra snacks or mini-meals. Fiber also helps manage blood sugar levels and supports gut health by feeding those beneficial bacteria, so without enough, you may experience fluctuations in overall digestive health. 

How to Find Fiber and Fill the Fiber Gap

As a registered dietitian nutritionist (RDN), I often worry about the fiber gap in our diets because fiber is ​​crucial to our overall health. Modern-day diets are very different from those of our ancestors, who contained substantially more fiber due to the inclusion of various plant-based foods. Ancestral humans might have consumed as much as 100 grams of fiber daily. That’s simply astonishing!

While we can’t expect to match our hunter-gatherer ancestors, there are steps you can take to add more fiber to your diet. Here are my tips to help you fill your fiber gap:

Meet With a Registered Dietitian Nutritionist (RDN)

First and foremost, it’s important to speak with a registered dietitian nutritionist (RDN) or a qualified healthcare provider to determine if you are getting enough fiber in your diet. They can help you devise a plan to incorporate fibrous foods that are also practical for you to fit into your daily routine.

Add More High-Fiber Foods

This tip might seem simple, but it’s the most effective way to fill the fiber gap. I suggest eating a variety of your favorite fruits, vegetables, whole grains, and legumes. In addition to their fiber content, these foods deliver essential vitamins and minerals without adding many calories.  

Here are some of my fiber favorites:

• OLIPOP
• Lentils
• Mushrooms
• Artichokes
• Plums
• Oats
• Whole grains

Incorporate a Variety of Fibers

Plant-based foods contain diverse fiber types—remember, not all fibers are the same! For example, oats contain beta-glucan soluble fiber, whereas asparagus contains inulin. You can support the diversity of the bacteria in your microbiome by eating a wide range of plants and benefiting from the different fibers they contain.

Dr. Joanne Slavin, Ph.D., RD, says, “For most consumers, the best strategy to meet fiber recommendations is to find foods or beverages enriched with significant amounts of mixed fibers.” Incorporating a variety of fibers in your diet is critical since different fibers have different effects on the body. 

Look at the Ingredients List

When purchasing packaged foods and beverages, look at the ingredient list and nutrition facts label to determine how much fiber one serving of that food or beverage provides and what sources of fiber you’re getting. 20% or more of the daily value for a nutrient such as fiber is high, so consider selecting products with a higher fiber load. On the ingredient list, look for key terms such as: 

• Inulin
• Chicory root
• Oligofructose
• Acacia fiber
• Guar fiber
• Resistant starches or dextrins
• Galactooligosaccharides
• Fructooligosaccharides

Including one or a few of the above means the product is formulated with fibrous ingredients. 

Start Slow to Allow Your Gut to Adjust

If you are a low-fiber consumer to begin with, try gradually adding fiber-rich foods to allow your gut time to adapt to something new. Occasional bloating and flatulence may occur during this adaptation phase, but just know that this is completely normal and will subside with time. Be sure to drink more water and other fluids as you increase your fiber intake.

How OLIPOP Can Help Close the Fiber Gap

Although OLIPOP can’t (and doesn’t intend to) replace the fiber you can get from fruits, vegetables, whole grains, and legumes, it does complement any meal made up of these tasty foods! Each can of OLIPOP also contains our OLISMART blend of plant fibers and prebiotics, each hand-picked for their distinct biome-supporting benefits. OLIPOP provides a practical way to help fill the fiber gap.

By incorporating soluble fiber into our drinks, we’ve added a sneaky way to support your digestive system. Although you can’t see it, our plant fibers work with you through every sip! We’re looking to add fiber to your diet in a convenient, delicious, and discrete way to help make the fiber gap a little smaller.

Fiber & The Fiber Gap: The Takeaway

Fiber plays a crucial role in our health, especially our digestive health. Fiber can provide nourishment for bacteria or microbiota that live within us. These bacteria stimulate beneficial metabolites called short-chain fatty acids that our body uses as an energy source for other cells.[4] This also helps support the functioning of our immune system.

In the U.S. and Europe, we still need more fiber in our diet. However, proper meal planning and an eye for high-fiber food and drink sources can help close the fiber gap. So the next time you head to your kitchen for a meal or snack, think about what fibrous food sources you have on your plate or in your hand. As a reminder, OLIPOP is a high-fiber (and delicious) beverage that can help close the fiber gap. Now, that’s a delightful way to load up on fiber!

Sources

1. National Center for Health Statistics. (2022, August 9). What We Eat in America, DHHS-USDA Dietary Survey Integration. U.S. Department of Health & Human Services. https://www.cdc.gov/nchs/nhanes/wweia.htm 
2. Miketinas, D., Tucker, W. J., Douglas, C. C., & Patterson, M. (2023). Usual dietary fibre intake according to diabetes status in USA adults – NHANES 2013–2018. British Journal of Nutrition, 1–9. https://doi.org/10.1017/s0007114523000089 
3. Stephen, A. M., Champ, M., Cloran, S., Fleith, M., Van Lieshout, L., Mejborn, H., & Burley, V. J. (2017). Dietary fibre in Europe: current state of knowledge on definitions, sources, recommendations, intakes and relationships to health. Nutrition Research Reviews, 30(2), 149–190. https://doi.org/10.1017/s095442241700004x 
4. McKeown, N. M., Fahey, G. C., Slavin, J., & Van Der Kamp, J. (2022). Fibre intake for optimal health: how can healthcare professionals support people to reach dietary recommendations? BMJ, e054370. https://doi.org/10.1136/bmj-2020-054370 
5. Slavin, J. (2013b). Fiber and Prebiotics: Mechanisms and health benefits. Nutrients, 5(4), 1417–1435. https://doi.org/10.3390/nu5041417 
6. U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th Edition. December 2020. Available at DietaryGuidelines.gov. 

Meet our Expert This article is written by Dr. Renee Korczak Ph.D., RDN, CSSD, LD. Renee is an advanced practice registered dietitian nutritionist with expertise in digestive health. Renee has her board specialty in sports dietetics and continues to be active in the digestive health and sports nutrition space. Outside of work, Renee enjoys time with her two children and husband. She enjoys world travel, cooking, and yoga.