The twice annual ritual of setting clocks for daylight saving time can affect diabetics adversely, especially those who use insulin pumps.
"Some diabetes patients who use insulin pumps may forget to change the clock that is found in these devices," said Saleh Aldasouqi, associate professor of medicine at Michigan State University in the US.
"Forgetting to change the time can result in insulin dosing errors that can be harmful," Aldasouqi added.
Daylight saving time or summer time is the practice of advancing clocks by an hour near the start of spring so that evenings have more daylight and mornings have less.
At the end of daylight saving time people again reset their clock to have an extra hour of morning sleep during the winter.
Dosing errors could cause too little or too much insulin being delivered at the right time for these patients, Aldasouqi noted.
Too much insulin produces hypoglycemia, which could be severe and trigger seizures, fainting spells or coma.
Hyperglycemia is a result of too little insulin being delivered and in the short term is not as harmful as hypoglycemia.
Aldasouqi said he has had a number of patients come into his office who have forgotten to make the time change.
"The implications of remembering to change the clock in these devices means so much more than just remembering to adjust the alarm clock for that extra hour of sleep," he stressed.
The study appeared in the Journal of Diabetes Science and Technology.