A Day in 50g of Fiber: How a Gut Health Scientist Feeds Her Microbiome

Megan Rossi, a gut health scientist and registered dietitian at King’s College London, aims for 50–60 grams of fiber daily—above the UK guideline of 30g—believing this level could boost mood and gut health by feeding the gut’s bacteria. Her day is built around high-fiber choices: a kefir-soaked overnight oats breakfast with seeds, fruit, and nuts; a lunch bowl aligning with her “Super Six” plant-based groups (grains, legumes, vegetables, nuts/seeds, fruits, herbs/spices), plus yogurt and olive oil; an afternoon smoothie packed with frozen fruits/vegetables and kefir; and a dinner stir-fry with protein, vegetables, and legumes, followed by frozen berries with kefir for dessert. She emphasizes gradual fiber increases to minimize bloating and relies on meal planning to hit fiber targets, highlighting the microbiome’s role in digestion, mood, and overall health while noting that more research is needed.