Levels of blood glucose in married people predicted how angry they would be with their spouse that evening

"In a 21-day study, researchers found that levels of blood glucose in married people, measured each night, predicted how angry they would be with their spouse that evening.

At the end of the 21 days, people who had generally lower levels of glucose were willing to blast their spouses with unpleasant noises at a higher volume and for a longer time than those who had higher glucose levels."