27/01/2013 18:12 GMT | Updated 29/03/2013 05:12 GMT

The Hidden Depressed Millions

There are millions of people in the UK living with chronic depression, surviving for years at a time with feelings of sadness, apathy and loneliness but, because their depression never reaches severe proportions, never seeking help.

This constant feeling of sadness is clinically referred to as dysthymia, but is more often known as low mood or depression. As many as three million people in the UK could be living their day to day lives without ever addressing it because it does not become severe enough to affect their ability to get up and go to work every day.

This lower-end depression is characterised by a minimum two-year period experiencing a low mood and other depressive symptoms while still carrying on a day to day life.

Sufferers will get up every morning, go to work, come home and cook dinner - all the same things people do every day - but all the while feeling desperately sad. They may also feel hopelessness, fatigue, low self-esteem, poor concentration, and will avoid going out socially.

It's much more common than you might think - up to six per cent of the population has dysthymia. This may not sound like a lot but it means that in a room of 100 people, as many as six of them could be regularly experiencing depressive symptoms but never seeking treatment.

It is massively underdiagnosed as a result, but people who experience these symptoms can benefit hugely from professional help.

Treatment involves cognitive behavioural therapy and, often, anti-depressants. Cognitive behavioural therapy will address the thought processes that cause depression, which helps people combat the cause of their feelings.

Anti-depressants are often necessary because people who experience low mood and depression are more likely to develop more severe symptoms as a result, causing what is termed 'double depression' which has a more severe effect on the person than those who experience depression without first having low mood and depression.

There are a number of ways that people can try and improve their mood:

• Get enough sleep - lack of sleep can have a very negative affect on mood

• Eat properly - a good diet that is nutritionally balanced will help ensure the body is properly fuelled to cope with any changes

• Exercise regularly - exercise releases endorphins which help improve feelings of happiness. It will also help get people in better shape physically, which can help reduce feelings of self-worthlessness

• Avoid alcohol and drugs - when we are feeling low alcohol can act as a depressant, making us feel sluggish, sad and melancholy

Keeping a record of thoughts and feelings can also be a real help when it comes to identifying patterns and behaviours. For example, people might find that their condition gets worse when they haven't exercised for three days or more, or after a night out.

Anyone who feels they might have low mood and depression should seek medical help. It's important to recognise that it won't go away on its own - it is not simply feeling sad - but that there can be a light at the end of the tunnel, and that light comes through accessing experienced help.