A dietary trend known as fibermaxxing encourages people to meet or exceed recommended daily fiber intake to support overall health. Researchers link adequate fiber consumption to better digestion, reduced risks of chronic conditions, and enhanced gut microbiota. Jennifer Lee from Tufts University explains the benefits and guidelines for incorporating more fiber into diets.
The term fibermaxxing has gained popularity on social media and in media this year, referring to the practice of consuming at least the recommended daily amount of fiber based on body weight. Fiber plays a key role in digestion, feeding beneficial gut microbes, and regulating blood sugar and cholesterol levels. Studies associate sufficient fiber intake with lower risks of obesity, diabetes, and cancers such as colorectal, breast, and prostate varieties.
Jennifer Lee, a scientist at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, focuses on how gut health variations and sex differences influence metabolism across life stages. She views the fibermaxxing trend as evidence of growing interest in extending healthspan—the years lived in good health—beyond mere lifespan. "There is a nine-year gap between living to a certain age in good health and then living in poor quality of health at the end of your life," Lee said. "Behavioral or nutritional strategies that can keep someone healthy are very on trend right now."
Low fiber intake may lead to metabolic and cardiovascular issues. "If you're not consuming a lot of fiber, you're possibly consuming calories from other macronutrient groups, and they may be high in carbohydrates or fats, which can lead to weight gain," Lee explained. The Dietary Guidelines for Americans, 2020-2025, recommend 22 to 34 grams of fiber daily for adults, varying by age and sex. A general rule is 14 grams per 1,000 calories consumed. For instance, women aged 19 to 30 need about 28 grams on a 2,000-calorie diet, while men in the same range require 34 grams.
Dietary fiber includes soluble and insoluble types. Soluble fiber dissolves in water, forming a gel that promotes fullness, stabilizes blood sugar, and lowers cholesterol absorption; sources include apples, avocados, bananas, broccoli, beans, and oatmeal. Insoluble fiber adds bulk to stool to prevent constipation and is found in whole grains, nuts, and seeds. Lee suggests aiming for twice as much insoluble as soluble fiber, such as 20 grams insoluble and 10 grams soluble for a 30-gram daily goal.
Many adults fall short of fiber recommendations, and supplements like capsules or powders can help, though gradual increases are advised to avoid digestive discomfort such as constipation or diarrhea. Resources from the U.S. Centers for Disease Control and Prevention offer tips for fiber-rich meals, including breakfast options to manage conditions like diabetes.
