A new study from Sweden has found the risk of having a heart attack rises nearly 40% on Christmas Eve.
The observational study analyzed the timing of 283,000 heart attacks over 15 years.
Researchers found specifically around 10:00 p.m. on Christmas Eve is the greatest risk.
Researchers also found mornings before 8:00 a.m. and Monday mornings to be other times related to high risk of heart attack.
They say more research needs to be done to find out what exactly causes the spikes.
You can read more in the medical journal the BMJ.