Guys, I'm sorry, but we have some bad news. That cigarette you thought would make you look cool could actually be the reason your penis has shrivelled.
According to specialists, smoking can have a number of negative effects on men, including erectile dysfunction and even shrinkage.
Speaking to Mirror Online, Harley Street urologist Marc Laniado revealed it is not as rare as you might think.
He said: "I see erectile dysfunction a great deal.
"To have a firm erection, you need sufficient blood flow. Smokers have a higher incidence of artherosclerosis in all blood vessels, including those in the penis, which can reduce blood flow.
"The chemicals in smoke may also have an effect on firmness; nicotine causes blood vessels to become narrow. This can be temporary or - eventually - permanent."
He went on: "Often they will say, 'My erection is not so good, I don't wake up with an erection in the morning as much as I used to or my penis isn't quite so hard when I'm having sexual relations.'
"But also sometimes people say that their penis is getting shorter as they get older, as smoking stops the blood flowing through the penis, which stops the spontaneous and nightly erections that are needed to stretch the penis and keep it at a good length.
"So in summary smoking can make your penis appear shorter or in fact become shorter."
But the specialist said it's not just men who could feel the impact of smoking on their nethers, women could also be in trouble.
He added: "Women's arousal is - if you think about it - also affected by blood flow to the area."
Experts have previously identified links between cigs and performance in the bedroom.
According to Medical News Today, cigarettes possess toxins which can damage the blood vessels in your man thing.
During a study in 1998, boffins at Boston University of Medicine examined the erect penises of 200 men and discovered that those men who were smokers were some way off from those who didn't.
The piece of research also concluded that smoking inhibits blood flow to your genitals, stopping the penis from stretching.
As well as smoking, medication could also have an effect on the size of your penis - including drugs like Adderall (often prescribed to people with attention deficit disorders) and some antidepressants and antipsychotics.
Some drugs used to treat prostate problems could also have an effect, with a 2012 study into a drug called finasteride revealing that men suffered from shrinkage and reduced sensation, and another published in the journal Urology finding that 41 percent of those taking the drug dutasteride suffered sexual dysfunction.