“Feed a cold, starve a fever.” It’s one of the many pearls of wisdom passed down through the ages by our well-intentioned but unscientific mothers. But is it a health myth or should you take it to heart?

Origins

No one really knows the origins of the axiom, but most accounts link it back as early as 1574, when dictionary writer John Withals wrote “Fasting is a great remedie of feuer.”

In those days, medical wisdom dictated that a drop in body temperature caused colds, while fevers produced a temperature spike.

The rationale behind “feed a cold, starve a fever” may have been that eating food and drinking tonic helped the body generate warmth during a cold, while laying off the calories helped temper the inner heat during a fever.

"I'm sure you could look through some old medical books and someone has mentioned it there, just like blood letting and other things that were recommended," says Scott Joy, MD, chief of clinical services with Duke’s Division of General Internal Medicine.

Click play to hear Joy discuss why maxims like "feed a cold, starve a fever" are so popular with patients:

Is it True?

Although a few small-scale studies have suggested that “feed a cold, starve a fever” loosely represents sound medical advice, Duke medical experts caution against putting too much faith in the adage.

“I think it was always pretty much dismissed as folklore,” says Denise Snyder, a nutrition scientist and clinical trials manager at the Duke University School of Nursing. “If you break it out and really think about it, there is some immune response if you eat less during a fever. But as a nutritionist, I certainly wouldn’t tell people to starve themselves.”

Snyder points out that you probably won’t feel like eating anyway -- loss of appetite is your body’s natural defense mechanism for fevers, as it helps the immune system focus its energy on fighting pathogens.

“You shouldn’t overconsume, but if you’re hungry you should eat,” she says, adding that fluids can only help fight the fever.

As for “feed a cold,” it’s simply a matter of keeping your nutrient levels up while the virus runs its course.

“Colds usually last longer than fevers,” Snyder says. “You need to be consuming food so you can fight it off -- especially fruit and vegetable juices and warm broths.”

Joy doesn’t want patients to get hung up on unproven treatments. “It’s important to stress what we know makes a difference, which is getting plenty of rest,” he says.

“Drinking plenty of fluids also makes a difference because it helps keep the secretions thinner and allows patients to get them out of their system lot quicker, alleviating symptoms such as a cough or nasal drainage.”

Joy also emphasizes the need to practice good hygiene when you’re sick -- whether it’s a cold or a fever. “Washing your hands often, covering your mouth when you cough -- those are great ways to reduce the spread of infection that are underappreciated.”

Click play to hear Joy discuss more proven forms of cold and fever treatment: