Most of us have heard the old adage, “feed a cold and starve a fever.” But have you wondered whether there is any truth behind the sentiment? Yale University professor and author of a new study published in the medical journal Cell had that thought. He wondered whether eating during a cold or flu would impact the immune system’s ability to fight the infection, so he and his team of researchers set to work to put the strange saying to the test, not just with cold and flu viruses but other infections as well.
Does Eating Impact the Outcome in Food Poisoning?
First the researchers explored the effects of eating on mice suffering from food poisoning, or the bacterial infection known as Listeria monocytogenes, to be more specific. Like you might expect, the mice naturally stopped eating after they began experiencing symptoms of food poisoning. And, it worked: they survived. But the ones that ate died. The researchers found that glucose was the factor that determined their fate. It appeared that glucose during the infection influenced whether the animals lived or died.
Now for the Flu
Next, the researchers assessed the effects of eating on animals infected with the flu virus (A/WSN/33). This time the results were quite different. The animals that were force-fed glucose survived while those that didn’t eat died. In the case of the flu, animals that ate lived.
It’s hard to imagine that anything as simple as the decision to eat or fast during an infection could determine an outcome of life or death, but that is exactly what this study found.
Why Did Food Make Such a Difference?
When the researchers analyzed the brains of mice that died from either of the infections, they found that different parts of the brain were affected by either the bacteria or the viruses. They believe that, depending on the type of infection, the body may have different needs (either for food or to fast).
Said lead study author, Ruslan Medzhitov: “Our study manipulated the ability of these mice to tolerate and survive infection without doing anything that had an effect on the pathogens themselves.” In other words, the animals were not given antibiotics or antiviral drugs or any other substances known to inhibit the infections. The only factor was whether or not the animals ate while they were infected.
While the research into eating during infections is young and still has not been conducted on humans, it does give us something to consider. We still don’t know the outcome of eating or fasting on the common cold, but when it comes to the flu (or at least this particular strain) we now know that the adage is FALSE. Keep in mind that one of the characteristics of the flu is that it is accompanied with a fever. If the animal study is any indication, we should reconsider the notion of starving a fever if that fever is caused by a flu virus.