Does ‘an apple a day keep the doctor away’ and should you ‘feed a cold, starve a fever’?

Aphorisms have been around since the beginning of medical practice. Essentially medical proverbs, some, but not all, are accurate.

Recently the online medical journal Medscape examined the accuracy of some common medical aphorisms to see whether they deserved their status as received wisdom.

Does the saying “cold hands, warm heart” ring true?

Implying that a cool exterior may mask a person’s real underlying warmth, it dates back to a collection of English proverbs published in 1903. But from a physiological point of view, is there any truth to the statement? Can you tell anything about the temperature of a person’s core from the temperature of that person’s extremities?

‘He’d lean over looking for a kiss from his gypsy girl while having a grope’

---

Irish scientists discover why babies need to move in the womb

---

How cigarettes are advertised and on sale near schools in many countries

---

There is a dearth of evidence supporting the “cold hands, warm heart” aphorism. Indeed, what evidence is available seems to point in the opposite direction. One study carried out in healthy people found that lower core temperatures in women correlated with lower hand temperatures.

How about “feed a cold, starve a fever”?

This expression, traceable back to the 16th century, implies that those with upper respiratory infection should eat well, but that a lighter diet is preferable in the presence of fever. For treating fever, Hippocrates recommended starvation. But fever increases metabolic rate, suggesting starvation is the wrong approach.

And what about that old reliable recuperative remedy, chicken soup? It supplies liquids, thereby preventing dehydration, and inhaling the warm vapour may moisten the roughened mucous membranes of the nose and throat.

Does “an apple a day keep the doctor away”?

While an exclusively apple diet has yet to be studied, there is a plethora of research to show that consuming several portions of fruits and vegetables daily (apples included), when accompanied by limited consumption of animal-based protein, has health benefits.

So this aphorism, dating back at least to the mid-19th century has stood the test of time.

“Whoever is desirous of pursuing his medical studies must pay a good deal of attention to the different seasons of the year” is credited to Hippocrates.

Drug-related complications have succeeded the dubious merits of bloodletting

So does climate influence health? Infectious diseases such as Lyme disease and influenza exhibit strong seasonal trends. As for non-infectious ailments, there is some evidence linking acute episodes of heart disease to cold weather. Pollution levels, which can be strongly related to climate, may presage a worsening of respiratory illness such as asthma. Global warming has already changed the distribution of tropical diseases like malaria and dengue fever and may have an increasing influence on health challenges of the future.

Can the cure be worse than the disease?

Most definitely. This aphorism appears to have its origins in the days of bloodletting, which was certainly worse than any disease it purported to treat.

But the aphorism has outlived now defunct treatments. That renowned creator of medical aphorisms, William Osler, said: "The person who takes medicine must recover twice, once from the disease and once from the medicine."

And of course there is modern research to show how that a proportion of modern illnesses are iatrogenic – the direct result of treatment or deficiencies in care. Drug-related complications have succeeded the dubious merits of bloodletting.

At the recent DotMD conference in Dublin (of which I am co-organiser), we were spellbound by the author of the book Medical Axioms. Dr Mark Reid is an internal medicine physician in Denver, Colorado. An inveterate tweeter of medical aphorisms, many inspired and moderated by his Twitter followers, Reid has put together a thought-provoking collection. While many deal with medical specifics, others will resonate with a wider audience.

Here are a few examples:

“Almost nothing in medicine is ‘always’ or ‘never’. Almost everything is ‘usually’, ‘sometimes’, ‘often’ and ‘rarely’.”

“No patient wants a hurried doctor. Speed up between patients and slow down with them.”

“The further into the future we ask medicine to predict, the less accurate and more expensive it becomes.”

And my favourite:

“Wisdom is the offspring of error and humility.”

mhouston@irishtimes.com