Light sleep
Stage N1 · about 5% of the night
The doorway into sleep, lasting a few minutes. Muscles relax, breathing slows and you are easily woken. Too much light sleep is a sign that sleep is broken up, for example by sleep apnoea.
Sleep clinic for adults and children · London and Surrey
Sleep is where your body repairs itself
Levitas Sleep finds out why you are not sleeping well, tracks your sleep night by night for up to 30 days at home, and builds an evidence-led plan that links sleep to your hormones, gut, weight, mood and long-term health.
What makes us different
A real-time 30-day sleep study
Most sleep tests record one or two nights. With the Empower sleep device we follow your sleep every night for 30 days, so we can see exactly which changes help you, and adjust your plan as we go.
Free sleep check
How well are you sleeping?
Answer a few quick questions about the past month to get your sleep score and our recommended next step. It takes about two minutes.
This sleep check is a simple guide developed by Levitas. It is not a diagnosis and does not replace a consultation with a clinician.
The science of sleep
The different types of sleep
Sleep is not one state. Each night you move through cycles of about 90 minutes, four to six times. Each type of sleep does a different job, so good sleep means getting enough of every stage, not just enough hours.
- Light sleep 6%
- Core sleep 49%
- Deep sleep 22%
- REM sleep 23%
- Time awake 26 min of 8 hours in bed
Core sleep
Stage N2 · about 50%
Heart rate and temperature fall. Short bursts of brain activity called sleep spindles help store memories and learning, and protect sleep from noise.
Deep sleep
Stage N3 · about 15 to 25%
The body's main repair time. Growth hormone is released, tissues and muscles repair, the immune system is strengthened and the brain clears waste. Deep sleep is concentrated early in the night and naturally falls with age.
Dreaming sleep
REM · about 20 to 25%
The brain is highly active while the body is still. REM sleep processes emotions, strengthens memory and supports creativity and mood. REM periods lengthen towards morning, so cutting sleep short loses the most REM.
What disrupts each stage
Alcohol reduces REM sleep and breaks up the second half of the night; sleep apnoea repeatedly pulls you out of deep and REM sleep; stress keeps sleep light; and late caffeine reduces deep sleep. Children and teenagers need more deep sleep for growth and development. The Empower 30-day sleep study shows how much time you spend in each stage, night by night.
Who we help
Conditions we assess and treat
Adults
- Insomnia: trouble falling asleep, staying asleep, or waking too early
- Snoring and suspected obstructive sleep apnoea
- Mouth breathing during sleep
- Daytime tiredness and fatigue
- Shift work, jet lag and body-clock problems
- Restless legs
- Sleep disrupted by menopause or low testosterone
- Sleep linked to stress, low mood or anxiety
- Unrefreshing sleep despite enough hours
Children and teenagers
- Snoring, mouth breathing and disturbed breathing at night
- Difficulty settling, night waking and early waking
- Sleep problems linked to ADHD and autism
- Low mood, irritability and anxiety linked to poor sleep
- Teenage body-clock delay
Causes and consequences
Why poor sleep affects your whole body
We label every claim by the strength of the evidence behind it, so you know what is proven and what is still being studied.
Common causes
- Stress and an overactive nervous system
- Sleep apnoea, snoring and mouth breathing
- Hormone changes, including menopause, low testosterone and thyroid problems
- Weight gain around the neck and abdomen
- Alcohol, caffeine, late meals and evening screens
- Shift work and irregular routines
- Pain, reflux, night-time urination, some medicines and low iron
Sleep and hormones
- Short sleep lowers testosterone and disturbs the daily cortisol rhythm
- Poor sleep raises the hunger hormone ghrelin and lowers the fullness hormone leptin
- A few nights of poor sleep reduce insulin sensitivity
- Growth hormone is released mainly in deep sleep
- Menopause and low testosterone also worsen sleep, creating a two-way cycle
Sleep and inflammation
- Ongoing short or broken sleep is linked to higher inflammatory markers such as CRP and IL-6
- Inflammation is a shared driver of many long-term diseases, and may worsen autoimmune and inflammatory conditions
Sleep and gut health
- Poor sleep and a disrupted body clock are linked to changes in the gut microbiome
- Sleep loss may increase gut permeability and digestive symptoms
- The gut may also influence sleep through the gut-brain axis
Mostly early and observational studies. This is a developing area.
Long-term risks
- Heart disease, high blood pressure and stroke, especially with untreated sleep apnoea
- Type 2 diabetes and weight gain
- Atrial fibrillation
- Depression and anxiety
- Road and workplace accidents
Sleep and the brain
- During deep sleep the brain clears waste, including amyloid
- Poor sleep is linked to cognitive decline and dementia risk
- Sleep is a core pillar of the Levitas approach to cognitive health
Integrated care
Sleep connects to everything we do
Sleep sits at the heart of Restore in the Levitas 10R approach. Your sleep plan links directly to our other services.
01
Brain and mood
02
Hormones
03
Gut health
04
Dental and airway
05
Diagnostics
Your safety
When to seek help urgently
Some sleep symptoms need medical attention straight away, before you book with us.
- 01Falling asleep while driving
- 02Witnessed pauses in breathing with severe daytime sleepiness
- 03Sudden, unexplained changes in sleep
- 04In children: breathing pauses, gasping, laboured breathing or poor growth
Your GPFor new or worsening symptomsNHS 111Urgent advice, day or night999EmergencyIf someone is in immediate danger
Drivers with diagnosed sleep apnoea that causes excessive sleepiness must tell the DVLA.
