What Is Fibermaxxing: Smart Health Strategy, or Just Another Trend?

Key Takeaways:

• Fibermaxxing is a dietary trend that promotes consuming more than the recommended daily amount of fiber in an effort to lose weight and reduce the risk for chronic diseases.

• Most Americans consume too little dietary fiber, which has been linked to poor digestion, higher cholesterol, and a greater risk for certain chronic diseases. 

• Eating excessive amounts of fiber can lead to abdominal discomfort, gas, bloating, and in serious cases, intestinal blockage.

• Following a mostly plant-based diet is a more natural and balanced way to ensure you get enough fiber without relying on only one dietary element.

Move over protein-loading. The social media algorithm is buzzing with a health trend again, and this time it’s all about over-indexing for fiber-rich foods in your daily diet. As trends go, it’s easy to see the appeal of “fibermaxxing”—fiber is essential for gut health and overall wellness. But is more always better? Here we’ll take a look at the role of fiber in your diet, and what you need to know before maxxing out your intake. 

What is fibermaxxing?

Fibermaxxing is a trend that doesn’t have a formal medical definition but generally means consuming more than the recommended 25-35 grams of fiber per day. People adopt it in hopes of “fixing” their metabolism, speeding up digestion, losing weight, or even lowering their risk of chronic disease. To do this, some people include large amounts of fiber-rich foods in their diet, while others opt for fiber supplements to achieve these higher daily amounts of fiber. 

The case for fiber, and why it matters

Dietary fiber is the part of plant foods — like whole grains, vegetables, fruits, and legumes— that your body can’t fully break down, so it passes through to the large intestine where it supports digestion and gut health.It adds bulk to the food we consume which helps us feel fuller for longer, and helps keep bowel movements regular. While it’s been a significant component of the human diet for millions of years, only about 5 to 7% of American adults today consume the minimum amount of recommended daily fiber. Diets that are too low in fiber are often associated with health conditions like poor digestion, high cholesterol, obesity, and blood sugar imbalances. The general decrease in our fiber intake over the last few centuries is also believed to have upset the balance of the human gut microbiome, since fiber ferments in the gut to produce beneficial metabolites like short chain fatty acids, and helps regulate metabolism and hormone levels. 

There are two kinds of dietary fiber, each with its own key role to play in our metabolism:

• Soluble fiber dissolves in water. It attracts water into the intestines and turns into a gel during the digestive process. It slows digestion, which can aid in lowering blood sugar and cholesterol levels. Soluble fiber can be found in abundance in foods like apples, bananas, beans, berries, citrus fruits, oats, and peas. 

• Insoluble fiber, often found in the indigestible husks and skins of plant foods,does not dissolve in the stomach, and can help speed up digestion by moving food through your system more quickly. Foods that are high in insoluble fiber include whole grains like rice and quinoa, leafy greens, cruciferous vegetables like broccoli and Brussels sprouts, nuts, and seeds.

There’s also resistant starch, a type of carbohydrate that resists digestion in the small intestine and instead feeds beneficial gut bacteria in the large intestine. While not always listed separately, it’s often considered a special form of soluble fiber.

Is more fiber better? The pros and cons of fibermaxxing

Now that we know how beneficial fiber is for our bodies, and that consuming too little of it can lead to certain digestion-related conditions and disease, let’s talk about eating too much fiber. When it comes to fibermaxxing, is too much of a good thing better? 

The danger that many people face when attempting this latest dietary trend is taking “high fiber diet” to extremes, and overdoing their daily intake with additional supplements that can really throw the body’s natural processes off balance. Too much fiber, especially when introduced too quickly, can lead to its own digestive upset like bloating, gas, abdominal discomfort, diarrhea, potential nutrient deficiencies, and in more severe cases, intestinal blockages. If you plan to increase your fiber intake, it’s always a good idea to start slowly to allow your digestive tract to acclimate to the change, and be sure to drink plenty of water to avoid constipation since fiber absorbs more water in the intestines.

It’s also important to note that people with certain GI conditions have an even greater chance of digestive upset due to high-fiber diets. If you’re managing Crohn's disease, ulcerative colitis, gastroparesis, or are recovering from any kind of stomach or intestinal surgery, you should always consult your medical provider before embarking upon a major dietary change.

“Fiber is the food your good gut bacteria eats—also known as prebiotic fiber. But just like any ecosystem, balance takes time,” says Melanie Murphy Richter, MS, RDN. “Eating a massive amount of fiber overnight won’t suddenly multiply those good microbes—it can actually overwhelm your system. At the same time, we can’t fiber our way out of a diet filled with sugar and ultra-processed foods, either. When we do that, we’re actually feeding the less beneficial bacteria, which can crowd out the good. The real benefits come when you consistently nourish your gut community with the right kinds of fiber, giving beneficial microbes what they need to grow and thrive. That’s why gradual increases, not fibermaxxing, are the key to lasting gut health.”

The bigger picture: fiber and longevity

While fiber is an important building block of a healthy diet, it’s only one piece of the puzzle. The healthiest eating patterns, like those observed in longevity regions around the world, emphasize fiber-rich plant foods—but in balance with healthy fats, the right macronutrients, and essential micronutrients. This balance supports digestion, metabolism, and whole-body health, without the discomfort that can come from overloading on a single nutrient. The Longevity Diet, developed by Dr. Valter Longo, and backed by decades of research, follows this principle: a mostly plant-based diet, naturally abundant in fiber, is shown to support long-term health and vitality.

How Prolon delivers the benefits of fiber - in balance

These longevity-inspired eating patterns form the foundation of all Prolon products, from our  5-Day Fasting Mimicking Diet (FMD) to our Everyday Longevity foods. Rather than over-indexing on fiber alone, our products emphasize balance—combining fiber with healthy fats, micronutrients, and plant-based proteins in clinically designed proportions. The FMD, in particular, is built around fiber-rich plant foods—soups, bars, olives, and snacks—blended with other nutrients that work together to promote fat-focused weight loss, protect muscle, and support deep cellular renewal. This unique design allows the body to remain nourished, even in a fasting state, while activating powerful processes like autophagy. The result is improved digestion, cardiometabolic support, and measurable benefits for healthy aging.

While ensuring your diet includes the right amount of daily fiber is essential for optimal digestion and metabolism, overloading your system with too much of any one dietary staple is rarely the most effective way to achieve lasting health. Consult a dietician or your healthcare provider about how much fiber is optimal for your diet. 

Sources:

National Library Of Medicine. National Center For Biotechnology Information. “Closing America’s Fiber Intake Gap.” Website. 

National Library Of Medicine. National Center For Biotechnology Information. “Dietary Fiber Intake and Gut Microbiota in Human Health.” Website.

National Library Of Medicine. National Center For Biotechnology Information. “Dietary fiber intake and mortality in the NIH-AARP Diet and Health Study.” Website. 

National Library Of Medicine. National Center For Biotechnology Information. “Fasting-mimicking diet and markers/risk factors for aging, diabetes, cancer, and cardiovascular disease.” Website. 

National Library Of Medicine. National Center For Biotechnology Information. “Fasting-Mimicking-Diet does not reduce skeletal muscle function in healthy young adults: a randomized control trial.” Website. 

National Library Of Medicine. National Center For Biotechnology Information. “Fiber and colorectal diseases: Separating fact from fiction.” Website.

Nature Communications. “Fasting-mimicking diet causes hepatic and blood markers changes indicating reduced biological age and disease risk.” Website.