It’s claimed that 21 per cent of adults in the UK suffer from Seasonal Affective Disorder (SAD), caused by lack of sun during the winter months. So I was intrigued to hear from K Spa, based at London’s K West Hotel, which claims to have the answer: a treatment room that mimics natural daylight. Obviously it’s not quite the same as lying by a sun-drenched pool like this one, but the spa claims a session in its Sun Meadow room can really make a difference. Not many UK spas offer light treatment therapy, but we’ve found three more that do.Sun Meadow, K Spa, K West Hotel, London 

K Spa’s Sun Meadow is a large open-plan room with low lighting, birdsong, woodland wallpaper and a futon-style treatment bed for two. When you’re ready, beams of light are dispensed from the ceiling for 15 minutes, leaving you – the spa claims – feeling positive and re-energised. Due to its low intensity, the treatment can be repeated every other day and it may also help those suffering from eczema, psoriasis and arthritis. £15 for 15 minutes.Exterior, Lucknam Park, WiltshireHaslauer Reflective Sunlight Therapy at Lucknam Park, Wiltshire

Lucknam Park is the only hotel in the UK to offer this innovative light therapy treatment developed by an Austrian wellness company. Over 40 minutes the system replicates the changes of light, from sunrise to sunset, so you get the full benefit of a warm summer’s day. £30 for 40 minutes. Pool, Donnington Valley Hotel & Spa, Berkshire

Aqua Sun Therapy on offer at Donnington Valley is designed to be a whole beach experience: not only do you get sunshine, courtesy of a low-level UV light canopy, but you get the ocean, too, since the treatment takes place in a bath filled with mineral-rich water and with hot air jets to massage the body. For maximum effect, combine with a Thalgo body treatment, such as spoiling Polynesia Ritual. Bliss. From £36 for 25 minutes.Sun Therapy Lounge, Grange St Paul's Hotel, London EC4Sunlight Therapy at Grange St Paul’s Hotel, London EC4

The five-star Grand St Paul’s Hotel, close to St Paul’s Cathedral, boasts London’s only Sun Therapy Lounge, fitted with a full spectrum lighting and infrared heat to replicate natural sunlight. As well as a range of holistic therapies on offer in the Ajala spa, the hotel also has an 18m pool so you can recreate the whole ‘swim and sun’ experience. £20 for 30 minutes.