A 10-year-old girl with yellow dystrophic nails, bronchiectasis, chronic sinusitis and lower-limb lymphedema is presented. The underlying mechanism remains unknown although it has been postulated to be associated with lymphatic abnormalities. To date no causative treatment exists. Our patient was treated with conservative management, including a low-fat diet supplemented with medium-chain triglycerides. Moderate improvement in the lymphedema of the lower extremities was observed. To our knowledge this is the first case of yellow nail syndrome to be treated with diet.