It’s not always easy supporting a football club.

Fans are put through it all. The highs, the lows and everything in between.

It’s a real rollercoaster experience and one that’s made worse by the fact that everything that happens is beyond our control.

We weren’t the ones who hacked down the opposing player to concede a last-minute penalty.

And yet we have to live with the emotional consequences of such incidents.

How much we let football affect our lives depends on how deeply involved we get but new research suggests devoted fans are at risk of serious harm.

A study by Oxford University researchers found that loyal supporters experience such intense levels of physical stress while watching their team play that they may put themselves at risk of suffering a heart attack, per BBC.

The study tested saliva from Brazilian fans during their shocking 7-1 defeat to Germany at the 2014 World Cup.

It found that levels of the hormone cortisol rocketed during the semi-final loss.

Despite preconceptions that men are more “bonded to their teams”, researchers found no difference in the stress levels of men and women during the match.

Dr Martha Newson, researcher at the Centre for the Study of Social Cohesion at Oxford, said: “Fans who are strongly fused with their team - that is, have a strong sense of being 'one' with their team - experience the greatest physiological stress response when watching a match.”

"Fans who are more casual supporters also experience stress but not so extremely."

Raised levels of cortisol for a prolonged period can raise blood pressure, constrict blood vessels and damage an already weakened heart.

It can also give people a feeling of impending doom, that their life is in danger or they are under attack.

Previous research into the impact of following football found an increase in heart attacks among fans on important match days, whether they’re following club or country.

The latest study tracked cortisol levels in 40 fans’ saliva before, during and after three World Cup games.

The biggest signs of stress came in the semi-final.

“It was a harrowing match - so many people stormed out sobbing," Dr Newson told BBC News.

However, coping techniques such as humour and hugging were used to reduce stress to pre-match levels by the final whistle.

Dr Newson believes stadiums should help by dimming the lights and playing calming music after games.

She added: “Clubs may be able to offer heart screenings or other health measures to highly committed fans who are at the greatest risk of experiencing increased stress during the game.”