Restorative sleep refers to sleep which lasts a recommended amount of time, in which a person has progressed smoothly multiple times through the sleep cycle (composed of four individual sleep stages), followed by feeling refreshed, clear-minded, and physically rested upon waking up.1,2

Deep sleep is critical to restorative sleep, allowing for growth and recovery within your body – your body repairs and regrows tissue, and builds bone and muscle. Deep sleep may also strengthen (bolster) your immune system and other important bodily processes.2,3

REM (rapid-eye movement) sleep is believed to be essential for maintaining cognitive functions like memory, learning, cognition (intellectual activity) and creativity.2,3

Failure to obtain enough of both deep sleep and REM sleep could have profoundly negative impacts on your thinking, emotions, and physical health.2

What is non-restorative sleep?

Sleep is non-restorative when you wake up feeling unrefreshed – as if the sleep has not been good enough. Non-restorative sleep can occur if your sleep duration is short, or even if you have slept for 8 hours – leaving you feeling drowsy and tired – implying that the quality of your sleep has been impaired.1,3

Symptoms of non-restorative sleep include1:
  • Fatigue, low energy levels during the day
  • Excessive daytime drowsiness (somnolence)
  • Feeling tired upon waking up
  • Irritability, depression, panic attacks
  • Inability to concentrate and perform daily tasks efficiently, memory problems
  • Impaired immune system leading to frequent sore throat, colds or other health issues
  • Body pains
  • Difficulty falling asleep and/or staying asleep

Non-restorative sleep can be linked to several sleep-related disorders and other factors/conditions (e.g. age, gender, lifestyle habits, stress, poor sleep hygiene, shift work) that disrupt the length and/or quality of your sleep. Conditions that can cause non-restorative sleep include anxiety, gastro-oesophageal reflux disease (described as heartburn), restless leg syndrome, obstructive sleep apnoea, fibromyalgia syndrome (a condition that causes widespread pain throughout the body), chronic fatigue syndrome, overactive bladder and insomnia.1,3

Your doctor may use a questionnaire like the Nonrestorative Sleep Scale to identify and track your experience of non-restorative sleep.4

Not getting enough restorative sleep can affect your health in a variety of ways – causing pain, impaired judgement and learning, fatigue (extreme tiredness), fragmented sleep, weight problems, migraines, and mental health conditions (e.g. anxiety and depression).1,3

Over time, poor sleep can also lead to long-term (chronic) conditions like heart disease, high blood pressure (hypertension) and diabetes. Speak to your doctor if you regularly struggle with non-restorative sleep.3


We’ve created a booklet filled with useful tips to help you manage your insomnia.5

In preparing this article, every effort has been made to provide an objective overview. The content contained in this article contains medical or health sciences information as per cited articles for public information. The content of this article has been initiated and is brought to you by Sanofi South Africa.

  1. Pagano R. Why do I still feel tired after sleeping? How to deal with non-restorative sleep. 30 December 2018. Sleepline. Available online at [Accessed 30 August 2023].
  2. Suni E. Stages of sleep. 08 August 2023. Sleep Foundation. Available online at [Accessed 21 August 2023].
  3. Coelho S. Not all sleep is restorative – what to know about improving your rest. 17 October 2021. Healthline. Available online at [Accessed 30 August 2023].
  4. Wilkinson K, Shapiro C. Development and validation of the Nonrestorative Sleep Scale (NRSS). J Clin Sleep Med 2013;9(9):929-937.
  5. Tips to help you overcome insomnia and get the sleep you need. Patient resource. Sanofi. MAT-ZA-2100751-1.0-07/2021.