Pornography – whilst most see it as a simple bit of fun and escapism, for some it is a potentially dangerous route into excess.

Although there is little concrete evidence, experts are becoming increasingly convinced that pornography addiction is on the rise, thanks to easy access to adult films provided by free streaming sites like PornHub.

As in the case of most addictions, causes of porn addiction can be complex and vary between sufferers, from difficult home situations as children (including emotional neglect and abuse) to problems with relationships formed as adults.

Symptoms of pornography addiction can include severe feelings of guilt, a need to watch ever-more extreme sex acts to gain the same gratification (known as sensitisation) and a lack of libido when with a real-life partner, sometimes in the form of erectile dysfunction.

However, there are treatments available for pornography addiction on the NHS. The best known is talking therapy with a trained counsellor. Mental health charity Mind says the purpose of talking therapy is, through discussion, to “help you understand your feelings and behaviour better and, if you want, to change your behaviour or the way you think about things.”

In 2016, a BBC report quoted psychosexual therapist Angela Gregory, who blames the proliferation of freely available pornography online for a range of health problems she has seen in her patients.

She said: “What I’ve seen over the last 16 years, particularly the last five years, is an increase in the amount of younger men being referred.

“Our experience is that historically men that were referred to our clinic with problems with erectile dysfunction were older men whose issues were related to diabetes, MS, cardio vascular disease.

“These younger men do not have organic disease, they’ve already been tested by their GP and everything is fine.

“So one of the first assessment questions I’d always ask now is about pornography and masturbatory habit because that can be the cause of their issues about maintaining an erection with a partner.”

In 2014, German researchers at the Centre for Lifespan Psychology in Berlin found a possible link between watching more pornography and having a smaller brain.

However, since online pornography is still fairly new to the mainstream, there has been limited scientific investigation into its effects.

An addiction to pornography can also be connected to sex addiction, where sufferers can be tempted to carry out high-risk activities and can suffer comedowns after sex.

NHS Choices describes it as an “addiction [that] is similar to substance abuse, caused by the powerful chemical substances that are released during sex.”

Those who believe they might be suffering from sex or pornography addiction are advised to visit their GP to explore the options available.