Ask Healthy Living: Why Do We Lose Our Appetite When We're Sick?

Why Do We Lose Our Appetite When We're Sick?

Welcome to Ask Healthy Living -- in which you submit your most burning health questions and we do our best to ask the experts and get back to you. Have a question? Get in touch here and you could appear on Healthy Living!

"Ask Healthy Living" is for informational purposes only and is not a substitute for medical advice. Please consult a qualified health care professional for personalized medical advice.

Why do I have zero appetite when I'm sick?

You've probably heard the old adage "Feed a cold, starve a fever." While experts say neither dieting nor force-feeding yourself is likely to help you recuperate any faster, you may certainly find yourself straying from your regular eating habits when you're under the weather.

In fact, loss of appetite is a well-documented symptom of a number of illnesses, including one that often helps experts distinguish the flu from a bad cold. But why does it happen -- and how do we make sure we still eat enough to fuel our recovery?

"When we're sick or ill from many different conditions, our bodies mount a complex inflammatory response," Dr. Donald D. Hensrud, M.D., MPH, chair of the Division of Preventive, Occupational and Aerospace Medicine at Mayo Clinic, explains to HuffPost Healthy Living in an email. "As part of this response, we produce chemicals called cytokines, which have a wide range of effects and are partly responsible for the decreased appetite." Depending on your illness, hormonal changes may also play a role, he says.

Your lowered drive to chow down may actually free up some energy to mount that immune response, he says. "Digesting food also takes energy, so if we're not digesting food, it frees up energy to help fight an infection or illness." While a drop in appetite might help in the short-term, loss of appetite throughout a longer-lasting illness, like some cancers, can lead to detrimental weight loss, says Hensrud.

Of course, you might find yourself with impaired smell and taste during a bout of the sniffles. And when things don't taste or smell as yummy as normal, you may simply be less excited to dig in.

Loss of appetite may also discourage viruses from growing more. Eating less "may decrease certain substances that viruses 'feed' on," says Hensrud. Same goes for bacteria, which won't find as much glucose and iron in the blood to feed on if you're eating less. "This complex response is adaptive short term and can promote recovery and healing," he says.

But that doesn't mean you shouldn't eat. Actively trying to starve out sickness and thereby depriving your body of enough calories could actually hinder the healing process, considering your body needs considerable energy stores to send your immune system into high alert, Everyday Health reported.

Experts recommend listening to your body and eating when you're hungry, in addition to getting plenty of rest and fluids.

Have a question? Ask Healthy Living!

Go To Homepage

Before You Go


Immunity-Boosting Foods