Modern shift work pattern potentially less harmful to health

September 27, 2011, Queen's University

Recent research suggests that the modern day-day-night-night shift pattern for shift workers may not be as disruptive or as potentially carcinogenic as older, more extreme shift patterns.

"Recent research has suggested shift work could increase the risk of cancer, although the responsible for this observation is still unknown," says Anne Grundy, the paper's lead author and a doctoral student in the Department of and Epidemiology. "Our study indicates that the now common rotating shift pattern of day-day-night-night may not disrupt circadian rhythm or melatonin production significantly."

Melatonin is a hormone that has been shown to have and tumor suppressor qualities. Since the production of melatonin is tied to the light-dark cycle and peaks between midnight and 4am, shift workers who are exposed to light at night may have an increased risk of diseases like cancer.

Ms. Grundy and her research colleagues recruited 123 female shift workers at Kingston General Hospital (KGH). They tested the participants to determine both their peak melatonin levels and the overall change in their melatonin levels during a winter day shift and night shift and a summer day shift and night shift. During these testing periods, the participants wore light meters that objectively measured the surrounding .

The researchers found that the light level in the KGH wards at night is generally dim and that there is little difference in peak melatonin levels in working during the day or night shift. However, in instances where the levels of light increased during a , the workers'overall change in melatonin levels decreased slightly—a finding that is statistically significant.

"We've already seen a shift away from the older patterns of two weeks of days, two weeks of nights, and a short time off to more humane patterns of day-day-night-night then five days off, so it's possible that an intervention to combat the health risks of shift work has already occurred," says Ms. Grundy. "However, the overall change in levels that we found may still be a concern. We look forward to seeing other studies that either confirm our findings or that examine the impact of specific risk factors like extreme shift patterns and higher intensities of light at night."

Related Stories

Recommended for you

Women run faster after taking newly developed supplement, study finds

January 19, 2018
A new study found that women who took a specially prepared blend of minerals and nutrients for a month saw their 3-mile run times drop by almost a minute.

Americans are getting more sleep

January 19, 2018
Although more than one in three Americans still don't get enough sleep, a new analysis shows first signs of success in the fight for more shut eye. According to data from 181,335 respondents aged 15 and older who participated ...

Wine is good for you—to a point

January 18, 2018
The Mediterranean diet has become synonymous with healthy eating, but there's one thing in it that stands out: It's cool to drink wine.

Sleep better, lose weight?

January 17, 2018
(HealthDay)—Sleeplessness could cost you when it's time to stand on your bathroom scale, a new British study suggests.

Who uses phone apps to track sleep habits? Mostly the healthy and wealthy in US

January 16, 2018
The profile of most Americans who use popular mobile phone apps that track sleep habits is that they are relatively affluent, claim to eat well, and say they are in good health, even if some of them tend to smoke.

Improvements in mortality rates are slowed by rise in obesity in the United States

January 15, 2018
With countless medical advances and efforts to curb smoking, one might expect that life expectancy in the United States would improve. Yet according to recent studies, there's been a reduction in the rate of improvement in ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.