Longtime good friends are good for your health

Nautilus -   Good friends aren’t just good for a shoulder to lean on in tough times. Studies have shown for at least 40 years that having social support can protect against heart disease, cognitive decline, and even death. But new research suggests it’s not just about having friends in the moment: The depth and consistency of a person’s relationships over a lifetime have a huge impact on their health—and is even written in their DNA.

For the new study, researchers compared social experiences across the lifespan of more than 2,100 middle-aged adults in the United States to the biological clock embedded in their DNA. The hands of these biological clocks consist of epigenetic changes to DNA—specifically, patterns in the addition of a chemical called a methyl group to certain genes. Such methylation doesn’t cause mutation; rather, the process turns the gene on or off in different cells of the body at different times. Over time, methylation patterns on certain genes change and can be used as markers of biological aging, a measure of how rapidly cells wear down that can be faster or slower than aging by the calendar. An older biological age is a strong predictor of chronic disease and early death.