So you think you’re safe with the odd puff, do you? We reveal the facts as the NHS prepares to roll out lung cancer tests for all ex-smokers. Photo / Getty Images
So you think you’re safe with the odd puff, do you? We reveal the facts as the NHS prepares to roll out lung cancer tests for all ex-smokers. Photo / Getty Images
As soon as you stop smoking, change will start to happen.
After eight hours, nicotine and carbon monoxide levels in your blood fall by half. Your oxygen levels begin to return to normal. After 48 hours, carbon monoxide leaves your body and your lungs start to clear. Between two and 12 weeks the blood circulation in your body improves. After a year your risk of having a heart attack is half of someone who still smokes.
Quitting smoking at any age can lower the risk of lung cancer. However, the risk will remain higher than for those who never smoked.
As such, a mass NHS rollout of lung cancer tests for every ex-smoker has been hailed as the action needed to improve survival rates in the UK.
Lung cancer is Britain’s most common cause of cancer death. With a record number of people on NHS waiting lists, detecting cases sooner, it is hoped, will reduce the amount of treatment required and help clear backlogs.
Ministers are apparently poised to back the recommendation that will see mobile units and trucks appearing in supermarket car parks.
Lung cancer is Britain’s most common cause of cancer death. Photo / Getty Images
Already results from pilot schemes have found such checks were able to spot three-quarters of cases of lung cancer at stage one or two.
“This is a good news story because of the way lung cancer is,” says Professor Nick Hopkinson of the National Heart and Lung Institute at Imperial College London. “By the time it causes symptoms, it’s often too late for curative treatment. So the only way we’re going to stop it is by finding it at an earlier stage.”
There are thousands of carcinogens in cigarettes, such as aldehydes and nitrosamines, as well as heavy metals and carbon monoxide. These toxic materials damage the cells in our airways and trigger an immune response, which causes airways to become inflamed.
“They damage the DNA in cells so that they make cancer more likely to happen,” says Prof Hopkinson. “And then tiny particles of tar that pass into the bloodstream or the chemicals in them leach into the bloodstream and cause damage to other parts of the body.”
A study suggests that being a 'social smoker' is not substantially less risky than being a regular smoker. Photo / Getty Images
It’s not just cancer…
There’s really no part of the body that’s shielded from the effects of smoking. It causes cardiovascular disease, damaging blood vessels in the legs, brain and heart, which can lead to heart attacks and strokes.
People may smoke in the belief that it reduces stress and anxiety, which compounds the problem.
Smoking also causes damage to the eyes: “People are more likely to get cataracts and have macular degeneration,” says Prof Hopkinson. Smoking, or even being around second-hand smoke, degrades the building blocks of the skin: “It damages the skin by triggering the destruction of collagen and elastin.”
Damage to the lung tissue directly causes lung disease such as emphysema and chronic bronchitis. Prof Hopkinson says that chronic bronchitis and emphysema kill a similar number, if not more people, than lung cancer a year.”
Those with a history of smoking also have an increased risk of flu and pneumonia.
“You’re five times more likely to get flu if you smoke than if you don’t,” says Prof Hopkinson. He explains that the toxic materials in smoke activate the immune system in a random and unproductive way. “Particles of tarry material allow the virus to hitch on them and help them to get into cells and infect them.”
Each cigarette will produce a little spike of risk. Photo / Getty Images
Is being an occasional social smoker dangerous?
A 17-year-long study by Columbia University suggested that the risk of lung cancer death for “social smokers” – those who smoke less than 10 cigarettes per day – is not substantially lower than for those who smoke more than 20 a day.
“Each cigarette will produce a little spike of risk,” says Prof Hopkinson. So that one-off cigarette at a party isn’t as innocent as you think.
There is evidence that smoking at a lower level can still cause inflammatory changes. “There’s research that suggests that for a pack of 20 cigarettes, half the risk of that is from the first cigarette,” says Prof Hopkinson.
However, volume does play a role and broadly the risk of cancer is dose-related. The more years a person smokes, and the more cigarettes smoked each day, the more risk goes up. “So smoking five cigarettes a year isn’t as bad as smoking 15 a day, every day,” says Prof Hopkinson. “But it will still be causing some health risks. There is an increased risk from smoking more, but even smoking intermittently and being a social smoker is exposing you to a lot of toxic material.”
To get lung cancer you have to have damaged the DNA in enough cells that they start to reproduce out of control: “The more toxins they are exposed to the more likely that is to happen,” says Prof Hopkinson. “So the more you smoke the more likely it is to happen - and at a younger age.”
Susceptibility to lung cancer varies from person to person. Photo / Getty Images
Do we all share the same risk?
Susceptibility to lung cancer varies from person to person. “These things certainly do run in families. If there’s a strong history of smoking-related lung disease in your family your individual risk is going to be higher than someone who doesn’t have that family risk,” says Prof Hopkinson.
Genetics can influence even how much you smoke. “That is partly to do with the fact people have slightly different nicotine receptors,” says Prof Hopkinson. “Part of the risk is that people will smoke more and expose themselves to more for that reason. They’re just exposed to more cigarette smoke, not that they are more vulnerable.”
Certainly starting at a younger age increases the risk of lung damage, disease and cancer. Photo / Getty Images
Age is also a factor
Certainly starting at a younger age increases the risk of lung damage, disease and cancer.
“Being exposed to smoke in early life is very important,” says Prof Hopkinson. “People’s lungs grow and reach peak lung function around the age of 20 and from that point, it starts to decline as we get older. But if your lungs are damaged as they grow, and never reach their full potential then you always have a handicap. Your decline will happen from a lower base of function.”
Although he adds: “If someone smoked a dozen cigarettes in their late teens and they’re 75 now, their risk is not going to be much higher.”
Look after your lungs
In people who have lung disease caused by smoking, quite often a lot of the underlying processes are not reversible, says Prof Hopkinson: “Lungs don’t grow back. They don’t recover. The airways stop being inflamed, so you’re less likely to have bronchitis and chest infections, but mostly it’s about improving lung function rather than repairing.”
The main ways to maintain good lung function after quitting smoking are a healthy diet and exercise.
“Exercise probably has some protective effect for the lungs. The fitter you are the less your lungs have to work,” says Prof Hopkinson. “If you do have some lung damage, being fit is a way of compensating for that.”
Ten years after stopping smoking your risk of lung cancer falls to half of that of a smoker. Photo / Getty Images
Giving up smoking will reverse the damage
Ten years after stopping smoking your risk of lung cancer falls to half of that of a smoker. After 15 years, your risk of a heart attack is the same as someone who has never smoked. “Modelling of the disease risk for ex-smokers shows that it returns to normal by the time you’ve quit smoking for 10 or 15 years,” says Prof Hopkinson. So it’s never too late to quit.
The most important point, says Prof Hopkinson, is that from the moment you stop smoking, you transform your risk of lung cancer and disease.
There are still about 6.5 million people in the UK who smoke, and two out of three people who continue to smoke will die from a smoking-related disease.
“Helping people to stop smoking is one of the few health-care interventions that actually saves money in one year,” says Prof Hopkinson. The figure estimated by the Royal College of Physicians is that spending £20 million (NZ$41 million) on smoking-cessation services in hospitals saves about £80 million (NZ$166 million) in the same year.
“These are benefits felt within a few months from a healthcare point of view,” says Prof Hopkinson.
The personal health benefits, however, are priceless. “You rapidly reduce your risk of stroke, heart attack or a chest infection once you quit smoking.”
