The Unexpected Reason We Tend To Be Healthier In The Summer

By: Agata Blaszczak-Boxe Published: May 12, 2015 01:05pm ET on LiveScience. The activity of human genes changes with the seasons, and with it, immunity changes too, according to a new study. Seasonal changes in gene activity mean that the immune system revs up inflammation in the winter, researchers found. This may help explain why the symptoms of inflammation-related conditions — such as heart disease and rheumatoid arthritis — often worsen in winter, and why people tend to generally be healthier in the summer. "Our results indicate that, in the modern environment, the increase in the pro-inflammatory status of the immune system in winter helps explain the peak incidences of diseases that are caused by inflammation, by making people more susceptible" to inflammation's effects, said study co-author Chris Wallace, a genetic statistician at the University of Cambridge in the United Kingdom. In the study, researchers examined genetic data from blood samples and fat tissue of more than 16,000 people who lived in both the northern and southern hemispheres, in countries that included the United Kingdom, the United States, Iceland, Australia and The Gambia. The researchers found that the activity of almost a quarter of all human genes — 5,136 out of 22,822 genes tested in the study — vary over the seasons. Some genes are more active in the summer, whereas others are more active in winter, the researchers found. [11 Surprising Facts About the Immune System] These...
Source: Science - The Huffington Post - Category: Science Source Type: news