“As we age, the lung tissue becomes less stretchy, so it doesn’t expand and contract as easily. This makes it harder to take deep breaths and fully empty the lungs,” writes Whimsy columnist CLIVE WILLIAMS.

“People are so rude to smokers. You’d think they’d try to be nicer to people who are dying.” –Roseanne

What happens to our lungs as we age, and how do they compare from their peak performance – at ages 20-25 in women and 25-30 in men – with how they perform at ages 70-80?

Well, as we age, the lung tissue becomes less stretchy, so it doesn’t expand and contract as easily. This makes it harder to take deep breaths and fully empty the lungs.

We have weaker respiratory muscles meaning that the diaphragm and chest wall muscles lose strength, reducing the power of inhalation and exhalation. 

There are also changes in the chest wall. The rib cage stiffens with age due to calcification of cartilage. This limits chest expansion. There is less efficient gas exchange. The number of functioning air sacs gradually decreases, and their walls may thin or lose surface area. This reduces how much oxygen can pass into the blood. 

The clearance systems are in decline. Mucus and pollutants aren’t cleared as quickly. This contributes to increased risk of lung infections in older adults.

By their late 70s-80s, even fit people may have only 60-70 per cent of their youthful lung capacity.

What does this mean for us in daily life? 

The decline is most noticeable during exertion (climbing stairs, swimming, running) because reduced reserve capacity makes breathing harder.

Exposure to pollutants, smoking, and chronic diseases can accelerate the decline. Regular exercise, staying active and avoiding pollutants helps preserve lung function.

The main health threat for the baby boomer generation is cigarette smoking. Smoking accelerates the natural ageing of the lungs, often by decades, and damage can be extensive depending on how long and how heavily someone smokes. 

Early evidence is that while vaping carries a lower cancer risk than smoking it carries increased risks of respiratory and cardiovascular problems.

By age 65 a healthy non-smoker may still have 80 per cent of peak lung capacity. A lifelong smoker may have only 40–60 per cent, often with disabling breathlessness. 

On a positive note, after quitting smoking: Within weeks: airways become better at clearing mucus. Within months: coughing and shortness of breath improve as inflammation eases. Within years: the decline in lung function slows to near that of a non-smoker. Some capacity will be regained, but structural damage is permanent.

While exercise is invariably beneficial, jogging along busy roads can be bad for your lungs. Busy roads have high levels of nitrogen dioxide, particulate matter and other exhaust pollutants.

Long-term exposure can lead to reduced lung function, higher risk of asthma, bronchitis and other respiratory issues, and increased risk of heart disease and stroke.

The bottom line is look after your lungs if you don’t want to be gasping for breath in old age.

On a lighter note: After dying in a car crash, three friends attend an orientation session in Heaven. They are all asked the same question: “When you were in your casket and family and friends were mourning over you, what would you have liked to hear them say about you?”

The first guy responds: “I’d have liked to hear them say I was one of the greatest doctors of my time and a great family man”.

The second guy says: “I’d have liked to hear that I was a wonderful husband and a schoolteacher who made a huge difference to the children of tomorrow”.

The third guy thinks for a while and then replies: “I guess I’d have liked to hear them say, “Quick – call triple 0 – he’s moving.”

And Peter hops into the local theatrical agency. “What’s your act?” says the agent. “I’m Peter the parrot and I imitate a parrot,” says Peter. 

“Oh, please” says the agent, “I get at least one offer like that a week. Forget it – and get the hell out of here.”

Peter screeches in disappointment and flies out the window.

Clive Williams is a Canberra columnist