Access to clean water and soap not only improves hygiene but may boost growth in young children, research suggests.
A review of global data found evidence of a small increase in height - about 0.5cm - in under-fives living in households with good sanitation.
The studies took place in Bangladesh, Ethiopia, Nigeria, Chile, Guatemala, Pakistan, Nepal, South Africa, Kenya and Cambodia.
Poor growth affects 265m children globally with long-term health impacts.
The evidence from 14 studies involving nearly 10,000 children comes from a review of evidence known as the Cochrane review, led by the London School of Hygiene & Tropical Medicine (LSHTM) and the international charity WaterAid.