Missing out on an hour of daytime as the clocks roll back means many in Canary Wharf will “exist in the dark.”

The culture of early morning starts, lunch breaks snatched inside the malls and a Tube journey taken in the late evening could result in office workers not venturing outside all day.

The routine could spark danger signs for health according to east London counsellor Owen Redahan.

Lack of exposure to natural light together with the seasonal time shifts could prompt anything from mild winter blues to full-blown Seasonal Affective Disorder (Sad).

The West India Quay-based therapist said Sad, a form of depression, was a key reason clients sought his help throughout winter.

But what is Sad and how can those in E14 combat the symptoms?

Here, Owen shares his advice.

What is Sad?

While the exact cause is not known, it is thought Sad is linked to reduced exposure to sunlight which then affects the hypothalamus, the part of the brain that controls sleep, appetite and moods.

Statistics from the NHS suggest the condition impacts one in 15 people in the UK.

It is often sparked between the ages of 18 and 30 with symptoms beginning around September and November and continuing until April.

Owen said: “The reduced amount of light affects the production of certain body chemicals – serotonin and melatonin – which may affect the body’s normal daily rhythm.

“Fewer hours of sunlight mean less serotonin is produced, something which affects our moods and makes us more positive.

“When it is dark more melatonin is produced and we feel sleepy and in winter, some people produce larger amounts.”

How do I know it’s not just a case of the winter blues?

Symptoms include persistent low mood, loss of interest in activities, sleeping longer than normal and feelings of despair and guilt.

Owen said: “For sufferers, it’s a struggle to get through the day – it’s like pulling yourself through a bog – it really is a struggle. And for those who don’t suffer it’s difficult to understand.

“This is serious depression but it’s difficult to accept mental illness because you can’t see it.”

He added for those who has suffered Sad in previous seasons, combating the anxiety attached was key.

He said: “See it as ‘I am taking control of my life, I have to accept that I have low moods, but it’s not going to control me’.”

What’s your top tip to beat it?

Owen said: “Going out for a half an hour walk, come rain or shine. In theory, everyone has a lunch hour but we are not good at taking it.

“If you go out with your friends for a walk that’s doing a massive thing – you’re removing yourself from work, and you’re getting natural light, and natural light will start to produce the feel-good hormones.”

But it’s not sunny outside?

Owen said: “It’s not specifically sunlight that’s important, it’s natural light. You might think because it’s a cloudy day it won’t help but it’s the importance of that light that gets through the clouds and stimulates the eyes.”

What’s your top seven quick-fire action plan?

  1. Sleep is important, but too much can have a negative effect, so sort out a routine and ideally get between seven and nine hours.
  2. Make your work environment as light as possible and get breaks away from the screen.
  3. Get regular outdoor exercise during the daytime
  4. Eat a healthy diet and avoid drinking lots of alcohol late at night, as alcohol is a depressant.
  5. Work at managing stress levels better and prioritise.
  6. Tell family and friends of your struggles so they better understand
  7. Talk to a counsellor who uses Cognitive Behavioural Therapy (CBT) methods which may help.

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