It is commonly said that we should eat when we have a cold but to try and skip a meal or two when we have a fever. Given the fact that fevers normally last only a couple of days during which time we do not really feel like eating anyway, there shouldn’t theoretically be too hard to skip eating for a short while. A cold, however, can last more than a week sometimes, making it difficult to stay away from food even if we tried.
So in theory, we should be able to feed a cold and starve a fever, yet is there any scientific truth behind the saying or not? First of all, the human body needs plenty of liquids to function properly and it also requires nutrients from time to time that cells turn into energy.
According to some theories, the self-inflicted anorexia that we experience when suffering from illness is supposed to boost our immune system to some extent. If this theory were true, then why abstain from eating only when we’re ill? Why not starve ourselves on a regular basis to trick our body into boosting our immune system altogether?
According to a study conducted by Dutch scientists more than a decade ago, subjects who were fed only water during testing experienced decreased levels of gamma interferon while those who were fed liquid meals showed an increase gamma interferon of more than four hundred percent.
You see, gamma interferon is one of the essential chemicals that make up our immune system, which is why you would normally expect high levels of it to travel through your system whenever you are suffering from any form of illness.
Given the fact that it was healthy meals who triggered an increased immune system activity during testing, it seems that you would do well to keep yourself nourished when suffering from any sort of affliction.
This being said, subjects who ‘starved’ themselves temporarily showed increased levels of interleukin-4, more than four times actually than subjects who were given liquid meals. The purpose of interleukin-4 is to help our body fight against bacterial infections by regulating immune reactions to infectious agents within our blood stream.
Therefore, it does indeed seem that starving yourself could technically boost your body’s ability to deal with fevers caused by infectious bacteria while healthy meals will help your immune system deal with virus-based infections like the ones you experience when you have a cold.
However, fever is commonly caused by a flu, which in turn is caused by a virus. Furthermore, the Dutch study wasn’t very large you see, as only six people took part in it. The author of the study also warned people not to change their eating habits based on whether they were suffering from a cold or fever, saying that although the study showed that starvation may in fact play a role in the way our bodies deal with external factors, the fact that it was so small should deter people from drawing any serious conclusions.
Last but not least, when the same study was performed with mice instead of human beings, the results were quite different. Meaning that although the mice showed an increased lifespan due to calorie restriction when suffering from a flu, feeding them properly showed similar results, thus rendering the study inconclusive. So there is no real scientific evidence to support the theory that starving a fever and feeding a cold would improve your immune system in any way.
All things considered, you should probably wait until a larger, more conclusive study is performed on the matter before putting your faith in what appears to be an urban myth. You should, however, do your best to drink a lot of fluids when suffering from both a cold or a fever as your body loses a lot of liquids when suffering from any type of illness.