Why do we get sick less in the summer?

Summer, in my opinion, is the most healthful season compared to the other three. As temperatures rise, fewer people huddle together indoors, reducing the concentration of germs and decreasing the risk of influenza A and other health issues linked to low levels of vitamin D. Various studies highlight that higher temperatures in summer months can indeed make us less prone to illness.

Decreased Exposure to Viruses in Summer

Winter's dry conditions are ideal for the proliferation of certain viruses, which is less likely in the more humid summer months. This leads to fewer viral particles in the air, thus reducing the likelihood of infection. Additionally, people tend to spend more time outdoors and in open spaces, instead of being confined to smaller, indoor environments where germs can easily spread.

Study on Immune Response

A study involving 16,000 participants revealed that in the northern hemisphere, the immune system is more active in winter, while in the southern hemisphere, it is more active during summer months. The difference is most pronounced at extreme latitudes, such as Iceland, where the sun shines almost 24 hours in summer and is practically non-existent in winter.

The Heat and Cold Myth

A common misconception was that getting chilled increased the chances of catching a cold. Despite this being largely debunked, recent research suggests that cold temperatures may indeed have an impact on immune function. Studies indicate that immune response in the nasal passages drops as the ambient temperature drops, potentially making it easier to catch a cold in colder months.

The Role of Vitamin D and Sunlight

The sun is a source of energy, not just light, but also vitamin D. While too much sunlight can lead to skin cancer, controlled amounts of sunlight with proper sunblock protection can be beneficial. Vitamin D plays a crucial role in immune response, and low levels have been linked to an increased risk of influenza A and other illnesses. In the summer, people are more likely to be exposed to sunlight, which can help maintain optimal vitamin D levels.

Hand Hygiene in Summer

One key factor often ignored is hand hygiene. Less people are rubbing their runny noses on surfaces, but this doesn't mean handwashing habits improve in summer. Instead, people tend to wash their hands less often, which is a significant risk factor for the spread of germs. Proper hand hygiene, combined with increased outdoor activities, contributes to overall better health during the summer months.