Move Over, Protein. Fiber Has Entered the Chat.

For over a decade, protein has dominated the conversation around nutrition. It’s been added to everything from bottled water to breakfast cereal, promising strength, satiety, and weight loss. But in 2025, a quieter, more complex nutrient is finally having its moment: fiber.

At a major food science conference this summer—the IFT FIRST expo, hosted by the Institute of Food Technologists—ingredient makers unveiled a wave of fiber innovations with the kind of excitement once reserved for plant-based proteins. Think upcycled carrot pomace turned prebiotic powder, resistant wheat starch with 90 percent fiber, and customizable “fiber stacks” designed to boost function without digestive backlash [1].

But this isn’t just about marketing trends. The renewed focus on fiber reflects a deeper, overdue shift—one grounded in decades of research showing how essential it is to our health, and how little of it most of us actually get.

Why Fiber? Why Now?

Most Americans already get plenty of protein. Fiber? Not even close. Despite its critical role in health, more than 90 percent of women and 97 percent of men fall short of recommended daily fiber intake [2].

This widespread shortfall isn’t just a nutritional footnote—it has serious health consequences. A recent analysis of over 14,000 U.S. adults found that even modest increases in daily fiber were associated with measurable reductions in systemic inflammation—including hs-CRP, ferritin, and immune cell ratios [3]. Because chronic inflammation underlies many of today’s most common conditions—from cardiovascular disease to type 2 diabetes—closing the fiber gap may be one of the most effective steps we can take for long-term health.

Public awareness appears to be catching up. Nearly half of U.S. consumers now report actively trying to eat more fiber—putting it just behind protein in terms of dietary priority [4]. What was once dismissed as a “regularity nutrient” is now being redefined as a foundational element of metabolic and immune health.

What Makes Fiber Different?

Unlike protein, fat, or digestible carbs, fiber isn’t used for energy or stored in the body. It’s the part of plant foods we can’t break down. But that’s exactly what makes it so valuable.

Fiber travels through the digestive system largely intact, supporting health in multiple ways:

• Insoluble fiber adds bulk to stool and keeps things moving.
• Soluble fiber forms a gel that slows digestion, promotes satiety, helps reduce cholesterol absorption in the small intestine, and feeds beneficial gut bacteria.

Those microbes, in turn, produce short-chain fatty acids like butyrate that help regulate inflammation and support immune function. Fiber also helps stabilize blood sugar and improves insulin sensitivity—both critical for long-term metabolic health [5]. And given that cardiovascular disease remains the leading cause of death in the United States [6], fiber’s ability to lower LDL cholesterol and systemic inflammation is particularly relevant.

Of course, to get those benefits, you need to get fiber from the right sources.

The Plant-Based Edge—Powered by Whole Foods

And that’s where plant-based diets come in. Fiber exists only in plants. That simple fact gives plant-based and plant-forward diets a built-in advantage—especially when they emphasize whole, minimally processed foods. Fruits, vegetables, legumes, whole grains, nuts, and seeds don’t just contain fiber—they offer it in a variety of forms and contexts that support digestion, metabolism, immune health, and long-term disease prevention.

But this advantage depends on more than just the presence of plants—it’s rooted in the integrity of whole foods. A meal built from lentils, brown rice, leafy greens, and avocado delivers more than just fiber grams; it provides structure, synergy, and bioactive compounds that work together to promote health in ways isolated nutrients can't replicate.

That distinction matters. Today, fiber is being added to everything from animal-based yogurts to ultra-processed plant-based snacks in an effort to meet growing consumer demand. But simply adding fiber to a refined product doesn’t make it equivalent to eating fiber-rich foods in their natural state. These fortified items often lack the complexity, nutrient density, and metabolic impact of foods that are fiber-rich by nature—not by design.

Processed products can still have a place—especially for convenience or when transitioning to healthier habits—but they’re not a substitute for a dietary foundation built on whole plant foods. Relying on powders, fiber bars, or protein-fortified snacks to close the fiber gap misses the bigger picture. The real benefits of fiber come from how it’s delivered in nature—woven into foods with structure, nutrients, and complexity that no additive can mimic.

That said, if you’re reaching for packaged foods, some options are clearly better than others.

The 10:1 Rule for Smarter Choices

How can you tell if a packaged food is genuinely fiber-rich or just marketing a “whole-grain” halo? Use the 10:1 ratio: for every 10 grams of total carbohydrates, a food should have at least 1 gram of fiber.

This shortcut—validated in both U.S. and international populations—correlates with lower intake of added sugars and sodium and better cardiometabolic health overall [7, 8]. If a granola bar lists 30 grams of carbs but only 1 gram of fiber, it’s likely doing you more harm than good. One with 3 grams or more? A far better choice.

Choosing high-fiber foods is easier when you know what to look for—but understanding why it matters is just as important.

A Nutrient Worth Paying Attention To

We often frame nutrition around excesses (sugar, sodium, saturated fat) or deficiencies (vitamin D, calcium, iron). Fiber doesn’t fit either narrative. Instead, it unlocks benefits only it can deliver.

Fiber regulates digestion—but it also regulates you: your appetite, blood sugar, immune response, and even mood through the gut–brain axis. It supports a thriving gut ecosystem and lowers the risk of the very conditions most Americans want to avoid. Yet most of us still come up short.

If protein defined the last decade of health marketing, fiber may define the next. It’s less flashy, less hyped, but far more deserving of our attention.

References

1. Ataman D. “Is fiber the new protein?” FoodNavigator-USA. July 21, 2025. https://www.foodnavigator-usa.com/Article/2025/07/21/is-fiber-the-new-protein
2. Thompson HJ. “The Dietary Guidelines for Americans (2020–2025): Pulses, Dietary Fiber, and Chronic Disease Risk—A Call for Clarity and Action.” Nutrients. 2021;13(11):4034. doi: 10.3390/nu13114034 • https://www.mdpi.com/2072-6643/13/11/4034
3. Qi X, Li Y, Fang C, et al. “Higher dietary fiber intake is associated with favorable systemic immune-inflammation indices in U.S. adults: NHANES 2015–2020.” Front Nutr. 2023;10:1216445. doi: 10.3389/fnut.2023.1216445 • https://pubmed.ncbi.nlm.nih.gov/37720377/
4. Wilson C. “Protein, fiber at the forefront of functional ingredient trends.” Food Business News. July 15, 2025. https://www.foodbusinessnews.net/articles/28629-protein-fiber-at-the-forefront-of-functional-ingredient-trends
5. Lu K, Yu T, Cao X, et al. “Effect of viscous soluble dietary fiber on glucose and lipid metabolism in patients with type 2 diabetes mellitus: a systematic review and meta-analysis of randomized clinical trials.” Front Nutr.2023;10:1253312. doi: 10.3389/fnut.2023.1253312 • https://pubmed.ncbi.nlm.nih.gov/37720378/
6. Ahmad FB, Cisewski JA, Anderson RN. “Leading causes of death in the US, 2019–2023.” JAMA. 2024;332(12):957–958. doi: 10.1001/jama.2024.15563 • https://jamanetwork.com/journals/jama/article-abstract/2822207
7. Skerrett PJ. “The trick to recognizing a good whole grain: Use carb-to-fiber ratio of 10-to-1.” Harvard Health Blog. Jan 14, 2013. https://www.health.harvard.edu/blog/the-trick-to-recognizing-a-good-whole-grain-use-carb-to-fiber-ratio-of-10-to-1-201301145794
8. Fontanelli MM, Micha R, Sales CH, et al. “Application of the ≤ 10:1 carbohydrate-to-fiber ratio to identify healthy grain foods and its association with cardiometabolic risk factors.” Eur J Nutr. 2020;59(7):3269–3279. doi: 10.1007/s00394-020-02259-6 • https://pubmed.ncbi.nlm.nih.gov/31865421/