It is not clear how eating junk food, typically high in animal fat or saturated fats, can lead to the disease, but doctors believe it pushes up the chances of genetically susceptible people developing it.

London - We have long known it is bad for your waistline.

But fast food can also be bad for your mental health, according to research.

Foods such as hamburgers, hotdogs and pizzas heighten your chance of developing depression.

Junk food consumers were 51 percent more likely to suffer from the condition, compared with those who ate little or none.

As well as problems with mood, those eating fast food were more likely to be single and less physically active.

Almudena Sanchez-Villegas, who led the study, said the findings backed up previous studies that had made the link with depression.

The study looked at 8,964 participants who had never been diagnosed with the problem nor had taken anti-depressants.

They were assessed for an average of six months, and 493 were diagnosed with depression or started to take anti-depressants – 51 percent more than would normally be expected.

The study was done by the universities of Granada, in Spain, and Las Palmas de Gran Canaria, in the Canary Islands.

It was published in the journal Public Health Nutrition. - Mail Foreign Service