The links between sleep and mental health

IOL News

08-07-2025

Anxiety, depression and poor sleep are closely linked, and in many cases, the underlying sleep disorder remains undiagnosed – worsening people's mental health and quality of life. According to Dr Alison Bentley, medical doctor at the Restonic Ezintsha Sleep Clinic in Johannesburg, the relationship between sleep and mental health is complex, but worth understanding to improve both.
'Sleep is like servicing the car of your brain and body – and it needs to happen every night,' says Dr Bentley. 'Poor sleep doesn't just make you tired; it affects your mood, memory, focus and self-confidence, and can increase your risk of developing depression and anxiety for years to come,' she said.
Restonic SA is the largest bed manufacturer in southern Africa and is on a mission to help people understand the power of sleep. Through the Restonic Ezintsha Sleep Clinic, it aims to support local sleep research and training for medical professionals. Adéle de la Reÿ, Group Marketing Manager for Sleep Group, Restonic SA's parent company, says sleep remains an undervalued aspect of health, including mental health.
'Dr Bentley has taught me that mental health challenges and sleep disorders often exist in a 'chicken and egg' relationship,' she says. 'Anxiety and depression can cause sleep disruption, while insomnia and other sleep disorders like sleep apnoea or restless legs syndrome can also trigger or worsen mental health issues. That's why it's so important to draw attention to the relationship between sleep and mental health. More and more young people are turning to platforms like TikTok for mental health support, and while this is helping to remove the stigma around mental health challenges, it also means that misinformation is flourishing.'
Restonic is working with Dr Bentley to make credible medical information relating to sleep more accessible, whether for young people, the working population, or organisations looking to understand the role that sleep health plays in employee productivity and engagement. This includes a podcast series on sleep health, corporate health screening, and partnering with schools to work with educators and parents. De la Reÿ says that addressing sleep offers potential benefits to every area of health.
'Many people put their tiredness down to work stress, parenting, or just life. But sometimes it's a sleep disorder – and left untreated, that can do long-term damage to both physical and mental health,' she warns.
Sleep disorders have been linked to higher risks of cardiovascular disease, obesity, dementia, and even earlier onset of diabetes.
'Sleep also influences mental health in a big way, and we're trying to draw attention to that.'
For example, Dr Bentley references a study that followed doctors who had battled to sleep during exams and found they had a higher risk of depression – even 35 years later. Dr Bentley explains that insomnia – defined as getting too little sleep to function properly – is not a one-size-fits-all condition. Acute insomnia, often triggered by stress or illness, can become chronic if not treated early. Secondary insomnia occurs alongside conditions like arthritis, depression or anxiety. And when insomnia persists for three months or more, even after the original trigger is gone, it is classified as insomnia disorder – a self-sustaining condition that often requires its own targeted treatment.
While sleeping tablets may help in the short term, they don't solve the root of the problem. For long-term improvement, Dr Bentley recommends Cognitive Behavioural Therapy for Insomnia (CBTI) – a proven, non-medication-based programme that addresses unhelpful sleep habits, thoughts and behaviours.
'There are free CBTI apps available, and seeing a trained professional can be life-changing,' she says. 'From August the Restonic Ezintsha sleep clinic will be taking bookings for an insomnia assessment clinic as well as a face-to-face CBT-I clinic charged at medical aid rates.'
Dr Bentley highlights lesser-known links between mood and other sleep disorders. She explains that restless legs syndrome and sleep apnoea – a condition where breathing is repeatedly interrupted during sleep – can rob the body of deep, restorative sleep and leave people exhausted, irritable and vulnerable to depression. 'In men, sleep apnoea is a common but often missed cause of midlife depression,' she says.
'If you're waking up tired despite getting a full night's sleep, it may be time to get checked. A simple questionnaire or overnight sleep study can make all the difference.'
'Insomnia or poor sleep shouldn't just be seen as a symptom of mental health issues – they're often contributing to or even causing them,' Dr Bentley says. 'Treating both sleep and mood problems simultaneously leads to better outcomes all round. If you're struggling with sleep or feeling overwhelmed, don't wait. There is help. Better sleep can be a powerful step toward better mental health.'