Colds and flu

Updated 05 October 2015

Is it true that you should feed a cold and starve a fever?

We've all heard of the proverb: feed a cold and starve a fever. Where does this come from, and is there any truth in it? And where does chicken soup fit into treating colds and flu?


This winter, most of us will catch a cold. Our kids will probably catch at least two or three. We all know you are supposed to feed a cold and starve a fever. But does it really make any difference if they eat or not?

This proverb appears to have become popular in the nineteenth century. However, dozens of websites attribute the phrase back to the fourteenth century and Geoffrey Chaucer’s Canterbury Tales. 

But no such phrase exists by Chaucer. It seems that everyone simply copied a story, without checking its original source. This is also how many medical myths start.

Colds are caused by viruses that infect the nose, sinuses and throat. But the unpleasant symptoms (blocked and runny nose, cough, sneezing, sore throat and headache) are largely triggered by our body’s reaction to them, rather than any damage caused by these bugs.

The runny nose (often accompanied by sneezing) is caused by increased secretions from the glands in the nose and seepage of serum (the yellow cell-free part of blood) into the nose.

Progressively, white blood cells also find their way in and their presence causes the gunk coming out your nose to turn yellow or green, as these cells contain a green protein called myeloperoxidase. This change in colour is not caused by bacteria and does not mean you need to take antibiotics.

The blocked nose comes about as the large veins in your nose dilate to narrow the space available for air to flow, while at the same time, the volume of secretions are increased and their clearance is diminished, especially during the latter phases of a cold.

Curiously, one nostril is usually worse than the other, at any one time. And it’s not always the same one.

In fact, which nasal passage is most blocked usually alternates from one to the other over a period of several hours. This so-called “nasal cycle” is thought to be defensive response, possibly to keep one open while the other one is being pumped clean with protective fluids.

When you have a cold you often don’t feel much like eating anything.

This is the result of chemicals released by your body to fight off infection also affecting your brain. These same chemicals can also make you feel irritable, lethargic, or just plain miserable.

But why should your brain want you to starve if you are ill? One reason may be that you don’t want to waste precious energy finding food that you could otherwise use in getting well?

Of course this theory doesn’t wash if Mum has just made you chicken soup. But the modern brain still works much like a caveman’s did.

It has also been suggested that not wanting to eat may be an important natural defence mechanism just like a fever, which helps your immune system fight off infections.

In fact, if you force-feed mice during an infection they are actually more likely to die than if they only eat what they feel like.

These facts have led to the idea that there may have been a semantic shift in the idiom.

What we think of as “feed a cold, starve a fever” may originally have been “fede a cold starb o’feber” (fede = “stoke [a fire]”, starb = “die”, feber = “fever”) or “stoke the inflammation of an infection and you die”.

But while starving (in the short term) can keep a feverish mouse alive, this may have little relevance to an innocuous cold.

Most times grown-ups get a cold they don’t even get a temperature.

Adults generally save fevers for bugs they’ve never seen before or severe infections, like influenza. So you have a sore throat and a runny nose, but no fever or cough from the beginning, you’re probably just coming down with a common cold.

And so you may just as well feed (during) your cold, and save your starving for the fever.

For kids all bugs are new, so fevers are commonplace. This doesn’t mean they’re in any danger, but they’ll probably be more miserable than you are.

Whether or not you are feeding a cold or starving it makes little difference to the biology of a common cold. In the end, most colds are mercifully short lived and will peter out after a week or so, regardless.

But feeling healthy is much more than biology. When you’ve got a cold, food is essentially a comfort not a cure. And at these times we all could use some of that.

Read more:

How you recover your sense of smell after a cold

Common old wives' tales about the common cold

Natural relief from spring colds

This article was originally published on The Conversation. Read the original article.

The Conversation is a collaboration between editors and academics to provide informed news analysis and commentary that’s free to read and republish.


Ask the Expert

Flu expert

Dr Heidi van Deventer completed her MBChB (Bachelor of Medicine and Bachelor of Surgery) degree in 2004 at the University of Stellenbosch.
She has additional training in ACLS (Advanced Cardiac Life Support) and PALS (Paediatric Advanced Life Support) as well as biostatistics and epidemiology.

Dr Van Deventer is currently working as a researcher at the Desmond Tutu Tuberculosis Centre at the University of Stellenbosch.

Still have a question?

Get free advice from our panel of experts

The information provided does not constitute a diagnosis of your condition. You should consult a medical practitioner or other appropriate health care professional for a physical exmanication, diagnosis and formal advice. Health24 and the expert accept no responsibility or liability for any damage or personal harm you may suffer resulting from making use of this content.

* You must accept our condition

Forum Rules