Night shift work may stop body re­pair­ing daily da­m­age to DNA and trig­ger can­cer

Tehran Times - - SCIENCE -

Night shift work may stop the body re­pair­ing daily da­m­age to DNA and raise the risk of mu­ta­tions which lead to can­cer, a new study sug­gests.

The link be­tween work­ing at night and poor health has been known for sev­eral years, with those who work after dark more likely to suf­fer di­a­betes, obe­sity, poor fer­til­ity, heart at­tacks and tu­mors.

Sci­en­tists be­lieved that dis­rup­tion to the body’s nat­u­ral body clock was re­spon­si­ble for the in­creased risk of chronic ill­ness, but could never pin­point the mech­a­nism.

Now US re­searchers have dis­cov­ered that when peo­ple work nights they pro­duce 80 per cent less of a chem­i­cal which is a by-prod­uct of DNA tis­sue re­pair. They say it in­di­cates that the body is not car­ry­ing out the cru­cial restora­tion to cells which should hap­pen nat­u­rally overnight.

They be­lieve the ef­fect could be caused by a lack of mela­tonin, the sleep hor­mone, which is far lower among peo­ple who sleep in the day­time.

Dr. Parveen Bhatti, Fred Hutchin­son Can­cer Re­search Cen­ter, Seattle, Wash­ing­ton, USA, said if awake at night the body has ‘re­duced ca­pac­ity to re­pair and clear ox­ida­tive DNA da­m­age.’

“Over time, this ac­cu­mu­la­tion would likely in­crease the risk of can­cer across mul­ti­ple sites as has been ob­served among shift work­ers,” she added.

The study tested 50 night shift work­ers for lev­els of 8-OHdG - a chem­i­cal which is produced when DNA is re­paired. They then tested them again when they were work­ing days, and found lev­els jumped by 300 per cent.

They be­lieve that shift work­ers may need to take sleep hor­mone supplements to al­low DNA to carry out re­pairs as they sleep in the day.

Newspapers in English

Newspapers from Iran

© PressReader. All rights reserved.