Myth or fact? Starve a cold and feed a fever. Or is it the other way around?

Doesn't matter, actually. Whether you have a cold or a fever, you should eat normally (unless "normally" constitutes the grease-soaked buffet). The important thing for both is to stay hydrated -- especially if you have a fever. Lots of fluids will help flush your whole body of infection. And rest, rest, rest -- it helps T and B cells (natural bug ousters) prepare for the fight.

The main differences between viruses and bacteria have to do with their structure, size, and function. Bacteria are complex cells that have the ability to replicate themselves; viruses are about a hundred times smaller, much simpler on a cellular level, and without the tools to replicate themselves. A virus works by invading one of your cells and hijacking it -- essentially taking over its genetic code. When the virus uses the good cell's replication machinery, it's like the virus has gone to Kinko's and made millions of copies to send all throughout your bloodstream.

The most common virus is the cold, which is actually caused by several different families of viruses. The vast majority of viral cold infections do run their course and exit your body via the portholes most associated with blowing, sneezing, and coughing. Antibiotics -- when taken for viral infections like a cold -- can actually have a negative effect by killing only the susceptible bacteria and allowing more dangerous resistant strains to gain a stronger foothold.

Which is why you should stop pestering your doctor for antibiotics if you're told that your condition is a virus.