Our circadian rhythm, which regulates our heart rate and makes us tired, can also influence how well a wound heals — depending on the time of day the injury happened.
Disruption of this natural cycle is linked to sicknesses like cancer, diabetes, obesity and heart attacks. But researchers wanted to know how individual cells used the circadian clock to boost certain functions, like healing from a wound.
They found fibroblasts, the most common cells in connective tissue, worked faster to close open wounds during the active part of the circadian cycle, or when people were awake. When the cell hit its resting phase of the cycle — when people slept — wounds closed a lot slower.
Open wounds weren't the only injury that healed more quickly during the day. When researchers looked at historical data from the International Burn Injury Database, they found burn wounds sustained at night took about 60 percent longer to heal than daytime burns.
The study's authors said the new information might be useful for patients who are going to have surgery. If they can reset their cellular clocks before the procedure, they might recover more quickly.