Intense Light Therapy May Boost Heart Health

Influences Gene Involved in Circadian Rhythms

A novel use of intense light therapy may help reduce tissue damage experienced during heart attacks, according to a study from the University of Colorado, published in Cell Reports.

"We already knew that intense light can protect against heart attacks, but now we have found the mechanism behind it," says senior author Dr. Tobias Eckle, professor of anesthesiology at the University of Colorado School of Medicine in Aurora.

In studies with mice, the researchers discovered that intense light influences the functions of the PER2 gene, which is expressed by a part of the brain that controls circadian rhythms. By boosting this gene through intense light therapy, the researchers discovered that the mice's heart tissue received extra protection when it experienced problems with oxygen, such as during a heart attack.

Intense light also heightened cardiac adenosine, a specialized chemical that helps with blood flow regulation. In concert, both benefits helped protect heart health.

The researchers next worked with healthy human volunteers, exposing them to 30 minutes of intense light (10,000 lumens). As in the mice, PER2 levels increased in response to light therapy. In the humans, plasma triglycerides also declined and metabolism improved.

Light has long been known to play an essential part in human health, not only in regulating the circadian rhythm but in cardiovascular health as well. Prior studies have shown that more people experience heart attacks during the darker months of winter, even in states that traditionally get more sunshine, such as Hawaii and Arizona.

This study could have a significant impact on the treatment of heart patients in the future, Eckle says: "If the therapy is given before high risk cardiac and non-cardiac surgery, it could offer protection against injury to the heart muscle."

Source:, Aug. 18, 2019