What causes depression?

Nobody knows exactly what causes depression. This section looks at some of the things that might increase your risk.

Your body

Scientists think that if you have depression, some of the chemicals in your brain are out of balance. In particular, having lower amounts of a chemical called ‘serotonin’ in your brain may cause depression.

Changes in your hormones can affect your mood. These changes might be particularly noticeable for women during pregnancy or menopause.

The family connection

Depression seems to run in families. This could be because:

a) it is passed down in your genes, or

b) you have experienced other people’s low moods.

Your background or situation

Problems during your childhood might cause depression. Bad experiences can lead to you thinking negative thoughts about yourself or about the world.

Stressful events, including problems at home, a breakup, the death of someone you know, or losing your home or a job can also affect your mood. Doctors sometimes call these ‘triggers’ or ‘triggering events’ if they think that these problems have caused your depression.

Lifestyle

Good food, exercise and hobbies can make it less likely that you will become unwell. Having other illnesses or using drugs or alcohol might make it more likely. There is more information on these things below.

Food

If we eat badly then we may be at risk of physical health problems like obesity, heart disease and diabetes. In the same way, the things we eat may affect our moods and our risk of becoming mentally unwell. Some people deal with their depression by eating high-fat and high-sugar foods. This is called ‘comfort eating’, and it can make things worse in the long term.

Some top tips include:
•Eat regularly throughout the day,
•Drink plenty of water,
•Try to avoid too much caffeine – tea, coffee and chocolate,
•Try to keep a healthy weight,
•Eat fruit, vegetables and wholegrain cereals,
•Don’t drink too much alcohol.

If you have depression, eating well will probably not have an instant impact on your mood. However, it might make you feel better in the long term.

Exercise

Exercising regularly can help your mood. Finding something that you enjoy doing is important so that you will want to keep it up. Exercise may also help you to get to sleep. Getting proper sleep is important for your mental health.

You can try increasing the amount of exercise you do gradually. The amount you can do will depend on your age, physical health and your fitness. We have listed some options below:
•Going for a walk
•Cycling
•Gardening
•Jogging
•Playing a sport
•Going to the gym

In some areas, you may be able to get ‘exercise on prescription’ from your GP. For example, you could get some free sessions at a local gym.

Drug and alcohol use

Using drugs can affect the way your brain works. Scientists think that this can have long lasting effects on you. Regularly drinking too much alcohol may also cause depression.

There is more information on drugs and alcohol in our ‘Drugs, Alcohol and Mental Health’ section.

Other illnesses

You may feel low if you have a physical illness. This risk might be higher if you have a long-term or life-threatening illness. Some people with brain injuries and dementia will also have changes in their moods.