The link between inadequate sleep and depression

A study of 290,000 people showed 7-8 hours of sleep was the biggest determinant in lowering depression risk. 

The factors that influence the onset of depression are complicated and include a mixture of biological and lifestyle factors. In new research in Nature Mental Health, an international team of researchers, including from the University of Cambridge, looked at a combination of factors that might explain this link including:

- lifestyle factors

- genetics

- brain structure

- immune system

- metabolic system

By examining data from almost 290,000 people – of whom 13,999 had depression, followed over a 9-year period, the research team was able to identify 7 healthy lifestyle factors linked with a lower risk of depression. These were: 

- moderate alcohol consumption

- healthy diet

- regular physical activity

- healthy sleep

- no smoking

- low-to-moderate sedentary behaviour

- frequent social connection

Of all of these factors, having a good night's sleep between 7-9 hours a night made the biggest difference, reducing the risk of depression, including single depressive episodes and treatment-resistant depression by 22%.

Frequent social connection reduced the risk of depression by 18%, and was the most protective against recurrent depressive episodes. 

In people at genetic risk for depression, the team further found that a healthy lifestyle can cut the risk of depression, regardless of a person's genetic risk. Professor Barbara Sahakian, from the Department of Psychiatry at the University of Cambridge said: "Although our DNA – the genetic hand we've been dealt – can increase our risk of depression, we've shown that a healthy lifestyle is potentially more important".

I really love a good research finding, and this one really had me because I know for myself I'm a completely different person if I haven't had enough sleep. Those first few years with the twins, I felt so far from 'myself', and sleep deprivation was a big factor in that. 

We know sleep is important for mental health, but it's really one of THE most important factors. And how easy is it, to lie in bed all night scrolling on our phones way past when we feel tired? 

This is me reminding you to go to bed by 9:30pm tonight. Do it for next week, and feel the differences. Anything on your phone will also be there the next day, but you'll be a happier you with an extra 30+ minutes of sleep. 

Source: "healthy lifestyle can help prevent depression – and new research may explain why" - University of Cambridge