Why Do Some People Catch Colds Easier Than Others? | Genetics, Lifestyle & Immunity

Why do some people seem to catch every cold that goes around, while others remain relatively unscathed? The answer, according to researchers, is a complex interplay of genetics, lifestyle, and environmental factors. The common cold, caused by over 200 different viruses, typically affects adults two to three times per year and children six to ten times. But individual responses to these viruses vary significantly.

Genetic predisposition plays a crucial role in susceptibility to the common cold. A study from Yale University found that cells lining the airways react differently to rhinovirus, a primary cause of colds. Cells in the nose mount a stronger antiviral response, but this defense can be compromised when the airways are simultaneously battling other stressors like dryness or cold temperatures. “When your airways experience two different stressors, there’s a trade-off, which leads to susceptibility to infection,” explained senior researcher Ellen Foxman. This explains why some individuals are quickly sidelined by even minor environmental changes.

Lifestyle choices also significantly impact vulnerability to infection. Chronic stress elevates cortisol levels, weakening the immune system and slowing wound healing. Insufficient sleep and disrupted circadian rhythms also increase susceptibility, as do smoking and a poor diet. Understanding these connections is vital for promoting preventative health measures.

Environmental factors and exposure levels are also key determinants. Viruses spread easily in crowded spaces like offices and public transportation through coughing or contact with contaminated surfaces. Children and older adults are particularly vulnerable due to their developing or weakened immune systems, respectively. The Netherlands’ National Institute for Public Health and the Environment (RIVM) emphasizes that while genetic differences have the biggest impact, the specific effect can vary depending on the virus.