You tell yourself you're just tired but maybe you should be seeking help. Many of us simply don't understand what depression looks like
It always amazes me how long it took me to figure out I was depressed. My dad had bipolar and my sister was diagnosed with depression over a decade ago, so you'd think I'd know the signs. But it still took a persistent friend to persuade me that my low moods, constant tiredness, poor appetite and inability to concentrate were all signs of the same thing and that I really did need to seek help.
Statistically, between 8% and 12% of us will experience a period of depression before the year is out, according to the Office for National Statistics. But many will never be never diagnosed. Despite increased awareness of mental health issues, people can live with a range of symptoms without ever realising they are depressed - as I did for several months.
"Some of my patients have been surprised and shocked when I've told them they were depressed," says clinical psychologist Angel Adams. "They think it's something else. If they have a lack of energy or fatigue, they might just think they're doing too much. Sometimes they think, 'It's just this illness' or 'I had a break-up with somebody', but really they're experiencing depression as well as the illness or the grief reaction."
Many of us simply don't understand what depression looks like. "People don't quite understand that you can still function and have depression," says Adams. "A lot of people think if you have depression you're going to quit your job and so on, but many people continue to work, continue to function but to a very different degree. You don't have to be suicidal to be depressed. You can just be clinically depressed and think, 'This is the way my life is.'"
Although no two cases are ever exactly the same, there are a number of factors to look out for.
This is, of course, the most obvious sign of depression. "Often people with depression have a feeling of low self-esteem and unworthiness," says Adams. "A person who is depressed and doesn't know it may become more critical and judgmental about themselves - they might self-blame. And you can become much more irritable with other people."
The low mood may well be worse in the morning. "It's a phenomenon called diurnal variation, which is a great way of saying you feel much sadder in the morning than you do in the afternoon," says Paul Salkovskis, professor of clinical psychology and applied science at Bath University. "It's often accompanied by a mood flip. Around 2pm you suddenly feel a change, as if a switch has been flipped."
Lack of interest and enjoyment
Anhedonia, as psychologists call it, is another very common symptom of depression. In this state you no longer get pleasure from things you once enjoyed, and struggle to make any kind of effort.
"Anhedonia probably translates best as loss of interest," says Salkovskis. "It's feeling listless, feeling totally flat, as if the world is colourless, everything is rubbish."
This can extend to relationships, with the result that people with depression often become isolated. Adams says: "People who are depressed tend to find a sanctuary. They don't want to be around people, they don't go out as much, they spend more time at home."
Loss of appetite
People with depression may overeat, indulging in so-called comfort eating, but more often they lose their appetite - another example of anhedonia. "They simply lose the will to eat," says Salkovskis.
Decrease in libido
Anhedonia can also have an impact on your sex life. "It's scarcely surprising," says Salkovskis. "If everything is rubbish, presumably your relationship is rubbish, and everything is pointless, and why would your partner want to have sex with you anyway?"
There may also be a biological cause, as depression is linked with hormonal changes.
Insomnia and fatigue
Many people with depression report disturbance to their sleep patterns. Some find themselves sleeping too much due to constant fatigue, but wakefulness is more common.
"It can be difficult to go to sleep," says Salkoskis, "but typically with more severe depression it's about early waking - people wake up around 4am and can't go back to sleep."
Aches and pains
Depression can increase your susceptibility to pain. This may present as unexplained aches and pains that don't go away, even with treatment.
"Pain is an almost entirely psychological phenomenon," says Salkovskis. "What is happening in your life will impact on pain. A fine example is soldiers in wartime getting a finger shot off and being carried off the field in a state of euphoria, laughing. For most of us, if our finger was shot off, we wouldn't be laughing. Pain is made worse or better depending on your psychological state."
When you are depressed, your memory becomes "over-general" and you find it hard to recall details.
Salkovskis explains: "Imagine you lose your job and become severely depressed and then somebody says to you, 'You need to get another job.' If you're not depressed, you think, 'I should get my CV in order, I should register with a couple of agencies, I should ask around my contacts and see if there's anything going' - your memory is giving you highly specific things to do. If you're depressed, you're thinking, 'I have to get a job ... umm ...' You can't think beyond the general. That impairs problem-solving."
When you're depressed you're likely to have what psychologists call "elevated evidence requirement". In other words, you want to be more certain before making decisions - and struggle to trust your gut feelings.
"Using your gut is something reserved for a particular type of decision - those that are important to us," comments Salkovskis. "For example, you meet the man of your dreams and he asks you to marry him. You have to consider many different factors but the top level of decision making is the gut feeling. So if you're depressed, very important decisions in particular will be very hard to make."
In addition, if you're depressed you may simply be less motivated. "You know everything ends in failure, so there's no point," says Salkovskis.
If you recognise these symptoms in yourself or someone you know, it's important to seek help from your GP, local counselling service or a charity such as Mind.