Myth or Fact: Cold and Flu Season, According to a Family Medicine Physician

With cold and flu season here, family medicine physician Sarah Medley, M.D., of Baptist Health South Florida, is clearing up some of the most common myths patients bring into her office.

Wet hair, Medley says, won’t make you sick. A cold requires a virus — no pathogen, no infection, no matter how cold or damp you are. The same logic applies to cold weather itself: Temperature alone doesn’t cause illness. What winter conditions do is create more opportunities for viruses to spread; more time indoors in close quarters; cold, dry air where viruses survive longer; and lower vitamin D levels from reduced sun exposure.

The flu shot is another frequent source of confusion. Inactivated and recombinant flu vaccines don’t contain a live virus and cannot cause influenza. The live attenuated version can occasionally cause mild, self-limited symptoms like a runny nose or low-grade fever, but that’s not a true flu infection. Medley notes that postvaccination aches or a low-grade fever often just reflect a normal immune response kicking in.

Contagiousness is trickier than most people assume. The flu virus can be detected in the upper respiratory tract before symptoms even begin, and people who are presymptomatic or asymptomatic can still spread it. Medley’s advice: If you’re feeling even slightly off, assume you could still be contagious.

Antibiotics remain one of the most persistent misconceptions. Colds are viral, not bacterial, and a Cochrane review found antibiotics offer no benefit for the common cold, only added side effects like diarrhea and a risk of contributing to antibiotic resistance.

On home remedies, chicken soup actually holds up reasonably well. Research shows it has a mild anti-inflammatory effect that helps clear nasal secretions, offering real, if modest, symptomatic relief. Vitamin C, on the other hand, doesn’t shorten a cold once symptoms have started, though zinc taken within the first 24 hours has shown some benefit.

One warning sign worth taking seriously: Feeling better partway through a cold, then feeling worse again. Medley says that biphasic pattern can signal a secondary complication like bacterial sinusitis or an ear infection, and it’s worth getting reassessed rather than waiting it out.

Her bottom line for this cold and flu season: There’s no cure, so the real goal is managing symptoms with zinc lozenges, antihistamines, decongestants, Tylenol or NSAIDs through what’s typically a self-limited illness lasting up to two weeks.