Overindulging in the pleasures of life has been scientifically proven to shorten people’s lifespans, according to Professor Luke O’Neill.

Over drinking, heavily smoking and not exercising regularly were found to cause damage to the body from the age of 36.

“People who smoked, drank heavily or didn’t exercise, had much poorer mental health, first of all,” Prof O’Neill told the Show Me the Science podcast.

“[They also] felt less well overall and had a higher risk of heart disease and liver disease.

“Over time, following the people, these ill effects increased – but the point was, they were already evident for the 36-year-olds, but not younger.

“So, when they measured these various things, they noticed the 27-year-olds, no issues about mental health – on average of course – physical health and so on.”

Drinking stock, © PA Archive/PA Images

Prof O’Neill said these habits are particularly hard to shake as a person heads into middle age.

“One of the key outcomes from this – and the authors mentioned this – get in early with health advice, because if you can get someone in their 20s and especially in their 30s, to modify their lifestyle, it’ll stay with them,” he said.

“If they form, let’s call them bad habits early on, those bad habits keep going.

“It’s much more difficult to escape from the bad habits, if you start early on, is the way to think of it.”

Quitting smoking

However, for heavy smokers at least, if a person quits their bad habit before 40, there is evidence that much of the damage will be reversed.

“Even though the damage begins to appear in the mid-30s, if you quit – certainly earlier than 36, but slightly less than 40 – the evidence is you can expect to live as long as someone who never smoked,” Prof O’Neill said.

“So, if you’re a smoker now, you may have done the damage already, and you end up in the healthcare system.

“But let’s say there was no smoking before you’re 40, and anybody who is that age, under 40, you will live almost as long as someone who never smoked.”

Prof O’Neill said that those that smoke between the ages of 40 and 79 can expect to live an average of 13 or 14 years less than their peers.

Main image; Luke O'Neill in the Newstalk studio (L) and people holding up pint glasses (R).