The benefits of summer (or drawbacks, depending on your point of view) include longer days, warmer temperatures and no school. But suppose your health also improved during the warmest time of the year? Believe or not, research suggests that this might be the case.

Winter Woes

Appearing in a recent issue of the journal Nature Communications, this report certainly cast a large net, as data from over 16,000 adults was reviewed. These participants lived in a wide range of countries, including the United Kingdom, Iceland, Australia and the United States. Using blood and tissue samples from this group, the authors found that the behaviors of over 5,000 genes are affected by seasonal changes.

So how do these genetic changes affect the body’s health? The answer appears to be that these fluctuations in genetic behavior impact immune cells. Specifically, the researchers noted that some people had notably more immune-related inflammation in the winter than in the summer. Furthermore, the study noted that many of these same adults also exhibited higher numbers of proteins associated with cardiovascular and autoimmune diseases.

Seeking Sun

In light of the findings described above, the authors contend that genetic activity could explain why some inflammatory diseases tend to get worse in the winter, while conversely subsiding during the summer. In turn, the shifts in gene activity connected to such health woes might be a sort of evolutionary holdover.

In an interview with the website Live Science, study co-author Chris Wallace noted that “humans have been primed to promote a pro-inflammatory environment in our bodies in seasons when infectious disease agents are circulating.” In plain English, our ancestors likely sought out environments that facilitated disease-fighting inflammation. This might explain our continued tendency to spend more outdoors once the weather warms up.