Can Medical Screening Sometimes Do More Harm Than Good?
By Cedric Murray | Keep Well Nutrition & Health
We are often told that prevention is better than cure. But could there be occasions when looking for a medical problem actually creates one?
It’s a question worth asking, particularly as we grow older and become increasingly encouraged to undergo health checks, screening tests and medical investigations.
Let me make something clear from the outset. I am not against modern medicine, nor am I suggesting that people should ignore symptoms or avoid potentially life-saving screening.
However, I do believe we should question whether every abnormality discovered in the human body necessarily requires medical intervention.
After all, there is a difference between discovering something unusual and discovering something dangerous.
And sometimes, that distinction can be the difference between maintaining a healthy, independent life and opening what I call the medical can of worms.
When a Routine Check Becomes Something More
Imagine someone in their seventies.
They are reasonably fit, enjoy walking, eat sensibly, remain socially active and generally feel well.
They attend a routine health screening, perhaps simply because they have received an invitation.
During the examination, a small abnormality is discovered.
There are no symptoms, no discomfort and no obvious indication that anything is wrong.
Nevertheless, further investigations are recommended.
One test leads to another. Perhaps a scan is arranged, followed by a biopsy or specialist consultation.
Eventually, a diagnosis is made, and treatment is discussed.
What began as a routine examination has now become a significant medical event.
There may be anxiety, medication, possible surgery, recovery time and even complications.
But here is the question I want to raise.
What if the original abnormality would never have caused that person any harm?
Would they have been better off never knowing about it?
We cannot answer that question for every individual. But we do know that unnecessary diagnosis and treatment are recognised problems within modern healthcare.
Overdiagnosis: When Finding More Isn’t Always Better
The medical term for discovering a condition that would never have caused symptoms or harm during someone’s lifetime is overdiagnosis.
This is different from a false positive, where a test suggests a problem that further investigation shows is not actually present.
With overdiagnosis, the abnormality or disease is real. The problem is that it would not have affected the person’s health or lifespan.
Certain prostate and breast cancers provide examples.
Some prostate cancers develop so slowly that a man may live out his natural life without ever experiencing symptoms.
Yet once a cancer is discovered, the individual may face difficult decisions about treatment, including the possibility of side effects.
Similarly, breast screening can identify cancers that would never have become life-threatening, although it can also detect dangerous cancers early enough for treatment to save lives.
The difficulty is that medicine cannot always predict which abnormalities will progress and which will remain harmless.
This creates a genuine dilemma for doctors and patients alike.
The NHS Recognises the Problem
What many people may find surprising is that these concerns are not confined to critics of modern medicine.
The NHS and the UK National Screening Committee openly acknowledge that screening can produce both benefits and harms.
These include:
- False positive results that create unnecessary worry.
- False negative results that provide misleading reassurance.
- Overdiagnosis of conditions that would never cause harm.
- Unnecessary investigations and treatments.
- Physical complications and psychological distress.
The UK National Screening Committee recommends population screening programmes only when the evidence indicates that their overall benefits outweigh their harms.
That is an important distinction.
A medical test is not automatically beneficial simply because it can detect something.
Its value depends on whether the information gained is likely to improve health outcomes.
Are We Turning Natural Ageing Into a Medical Condition?
This is perhaps the part of the discussion that interests me most.
As we age, our bodies naturally change.
Our muscles, bones, joints, cardiovascular systems and metabolic processes all undergo changes over time.
Some of these changes may increase our risk of disease. Others are simply part of growing older.
Yet we increasingly live in a world where almost every aspect of ageing can be measured, monitored, investigated or potentially treated.
Blood pressure, cholesterol, blood glucose, bone density, hormone levels and countless other biological markers can all become subjects of medical attention.
Many of these measurements are extremely useful. For example, identifying and managing genuinely high cardiovascular risk can prevent strokes and heart attacks.
But I wonder whether there is also a danger of encouraging people to regard themselves as unhealthy simply because certain measurements fall outside a particular reference range.
A reference range does not always distinguish between health and disease, and a risk factor is not the same thing as an illness.
Could we be creating a generation of older people who spend more time worrying about what might go wrong than enjoying what is still going right?
I believe that question deserves serious consideration.
What About the Body’s Natural Ability to Maintain and Repair Itself?
My approach to health has long been influenced by the principles of naturopathy and the osteopathic philosophy I studied many years ago.
Central to that philosophy is the recognition that the human body possesses an extraordinary capacity for self-regulation, adaptation, maintenance and repair.
We see evidence of these processes every day.
Wounds heal, tissues regenerate to varying degrees, immune responses protect us from infection, and physiological systems continually adjust to changing demands.
Exercise encourages adaptation in our muscles, cardiovascular system and nervous system.
Good nutrition provides the materials required for normal bodily maintenance and repair.
Rest and sleep support recovery and regulation.
Of course, these natural processes are not limitless. Serious diseases can overwhelm the body’s defences, and medical treatment may be essential.
Nevertheless, I believe we should give greater consideration to supporting health before assuming that every biological irregularity requires intervention.
Sometimes the most appropriate action may be treatment. Sometimes it may be careful monitoring. And sometimes it may be no immediate intervention at all.
The challenge is knowing the difference.
When Treatment Creates Its Own Problems
Every medical intervention involves some degree of risk.
Medication can produce unwanted side effects.
Surgery can lead to complications.
Investigations may involve radiation exposure, infection risks or physical discomfort.
Even the psychological effects of receiving a diagnosis can influence someone’s quality of life.
For an older person, these consequences can sometimes be particularly significant.
Imagine someone who is independently mobile and enjoys an active lifestyle.
An unnecessary procedure results in complications, followed by several weeks of reduced mobility.
During that period, they lose strength, confidence and physical conditioning.
Recovery may take considerably longer than expected.
The original abnormality might have been harmless, yet the consequences of investigating or treating it have now affected the person’s independence.
This is a hypothetical example, but it illustrates why the possible harms of an investigation deserve as much consideration as its potential benefits.
When Screening Really Does Save Lives
We must also recognise the other side of this discussion.
There are conditions where early detection makes a substantial difference.
Bowel cancer screening, for example, can identify abnormalities that may develop into cancer, allowing them to be removed before they become dangerous.
Abdominal aortic aneurysm screening can identify a potentially life-threatening enlargement of the main artery before it ruptures.
Breast screening can detect some cancers at an earlier, more treatable stage.
These are important benefits that should not be dismissed.
The objective should never be to reject screening simply because it carries risks.
Rather, we should understand those risks alongside the potential benefits.
Nor should screening decisions be confused with seeking medical attention for symptoms. Persistent, new or unexplained symptoms deserve appropriate assessment, regardless of whether a previous screening result was normal.
Does Age Change the Balance?
I believe it can.
As we grow older, the potential benefits and consequences of medical intervention may change.
A treatment intended to prevent a problem twenty years into the future may have a different value for someone aged 85 than for someone aged 45.
However, chronological age is only part of the picture.
A physically active person in their eighties may have many years of healthy, independent living ahead.
Another individual of the same age may have substantial health limitations.
This is why I believe healthcare decisions should consider the individual rather than simply their date of birth.
Their physical condition, personal priorities, independence, likely treatment benefits and potential risks all matter.
And perhaps most importantly, the person should have a meaningful say in what happens to their own body.
The Importance of Informed Choice
Before agreeing to a screening test, I believe we should feel comfortable asking a few straightforward questions.
- What exactly are we looking for?
- What is the likelihood that this condition would actually harm me?
- How reliable is the test?
- What happens if an abnormality is discovered?
- Would treatment genuinely improve my quality of life or life expectancy?
- Is careful monitoring an alternative to immediate treatment?
- What are the possible consequences of doing nothing?
These are not unreasonable questions.
They are part of making an informed decision.
The NHS itself recognises that accepting or declining screening should be a personal choice, made with an understanding of the benefits, limitations and possible consequences.
My Thoughts: Health Should Be About Living, Not Simply Avoiding Disease
As a health, nutrition and exercise coach, my focus has always been on helping people maintain the best possible quality of life.
For me, healthy ageing is not simply about how many years we live.
It is about how well we live those years.
Can we remain mobile?
Can we maintain our strength and balance?
Can we enjoy our food, our families, our friendships and our independence?
Can we continue doing the things that give our lives meaning?
Modern medicine has an important role in helping us achieve these goals.
But so do regular physical activity, sound nutrition, restorative sleep, social connection and a positive approach to living.
I would like to see healthcare place as much emphasis on maintaining function and wellbeing as it does on identifying disease.
And I would like people to feel confident asking whether a proposed investigation or treatment is genuinely necessary for them.
Final Thoughts: Before Opening the Can of Worms
There is a saying that knowledge is power.
In healthcare, that is often true.
But medical knowledge can also bring uncertainty, difficult choices and unintended consequences.
Finding an abnormality is not necessarily the same as finding a problem that needs fixing.
Equally, feeling well does not guarantee that a serious condition is absent.
The real challenge is finding the right balance between prevention, early detection, appropriate treatment and respecting the body’s natural processes.
I am not suggesting that we should close our eyes to disease.
I am suggesting that we should think carefully before opening a medical can of worms that may never have needed opening.
Perhaps the most important question is not simply, “Can we find something wrong?” but “Will finding it help this person live a longer, healthier or better life?”
That, to me, is what good healthcare should be about.
Stay well, keep moving.
Cedric Murray
Keep Well Nutrition & Health
Strength Through Health
References and Further Reading
- UK National Screening Committee. The Pros and Cons of Screening. Explains false positives, false negatives and the potential harms of unnecessary treatment.
- UK National Screening Committee. Principles of Screening. Describes how screening programmes are assessed for benefits and harms.
- NHS. NHS Screening. Overview of NHS screening programmes, their benefits, risks and limitations.
- NHS. PSA Test. Explains prostate-specific antigen testing and the possibility of unnecessary investigations.
- NHS. Why Breast Screening Is Done. Discusses benefits, limitations and overdiagnosis.
- UK National Screening Committee. Informed Choice. Guidance on making personal decisions about screening.
Health information note: This article is intended to encourage informed discussion, not to replace individual medical advice. Decisions about screening, investigations or treatment should take account of personal risk factors, symptoms and advice from an appropriately qualified healthcare professional.
Test Your Knowledge
KEEP WELL · TEST YOUR KNOWLEDGE
The Medical Can of Worms
Eight questions about screening, overdiagnosis and making informed healthcare choices.
Around 4 minutes · Choose your answers, then see your score and explanations.
For general education only. Screening decisions depend on individual circumstances. Seek medical advice about new or persistent symptoms.