How often you change your bed linen is up to you but we recommend changing bed linen every one to two weeks. If you sleep in the bed less often, wear pyjamas or shower before bed, you might change your bed less often than if you shower in the morning, sleep naked or are a hot sleeper. Leaving it longer than 2 weeks can lead to a build up of dust mites which can cause allergies. It can also lead to staining on your sheets. Wash well, often, with warm water and you should be fine.