A social media trend known as "fiber maxxing," which sets a daily target of more than 50 grams of dietary fiber, is gaining traction. That is 1.7 to 2 times the amount recommended for South Korean adults. Doctors warn that pushing intake up over a short period puts the strain on the gut first.
Amir Khan, a general practitioner with Britain's National Health Service, discussed the diet on the 2nd on his podcast "No Appointment Necessary." Khan said he supports the broader push to get more fiber, but explained that people who normally eat little fiber and then hit the target overnight experience gas, bloating and irregular bowel movements. The reason is that they have yet to build up the gut bacteria needed to process the added fiber.
Fiber maxxing refers to filling every meal, snack and drink with fiber. Chia seeds, oats, beans, lentils and whole grains are the mainstays. Mixing psyllium husk or inulin powder into drinks to hit the target has spread alongside it. Khan said young influencers are packing fiber into every meal from morning to night.
The gap becomes clear against established benchmarks. The NHS recommends 25 to 30 grams a day. The South Korean standard is lower. The 2025 Dietary Reference Intakes for Koreans, released last December by the Ministry of Health and Welfare and the Korean Nutrition Society, applied a formula of 12.5 grams per 1,000 calories for adult dietary fiber, and set a floor of 30 grams for men and 25 grams for women aged 50 and over as a chronic disease prevention measure.
The benefits of dietary fiber are established. It feeds beneficial gut bacteria and makes bowel movements regular. It also helps with blood sugar management by increasing satiety. Research has also accumulated showing that higher intake lowers the risk of heart disease, type 2 diabetes and colorectal cancer. What matters is not the total amount but the pace of the increase. Khan advised going in stages rather than jumping from zero to 100 at once. Constipation gets worse if water intake is not increased along with fiber, because fiber needs to draw in moisture to pass through the gut.
Long-term excessive intake is a separate matter. Fiber binds cholesterol and fat and carries them out of the body, and minerals can be flushed out along with them. The Ministry of Food and Drug Safety warns that excessive intake can interfere with the absorption of calcium, vitamins and minerals, and advises caution for growing children, underweight adults and the elderly. Academics note, however, that research directly demonstrating this remains limited. Patients with irritable bowel syndrome may experience stomach pain, and those with Crohn's disease may in rare cases suffer intestinal obstruction.
With chia seeds, how they are eaten determines whether they are safe. They absorb up to 27 times their own weight in water and swell. The American College of Gastroenterology advises against swallowing them dry. A case reported at the ACG's 2014 annual meeting involved a 39-year-old man whose esophagus became blocked after he swallowed a tablespoon of dry chia seeds with water. Doctors spent several hours removing the seeds with an endoscope. The seeds should be soaked in liquid or wet food for at least 10 to 15 minutes until they form a gel before being eaten.
Khan said intake should be increased slowly while drinking plenty of water, so that gut bacteria can adapt and the full benefits of fiber can emerge.
