Doing the night shift throws the body "into chaos" and could cause long-term damage, warn researchers.
Shift work has been linked to higher rates of type 2 diabetes, heart attacks and cancer.
Now scientists at the Sleep Research Centre in Surrey have uncovered the disruption shift work causes at the deepest molecular level.
Experts said the scale, speed and severity of damage caused by being awake at night was a surprise.
The human body has its own natural rhythm or body clock tuned to sleep at night and be active during the day.
It has profound effects on the body, altering everything from hormones and body temperature to athletic ability, mood and brain function.
The study, published in Proceedings of the National Academy of Sciences, followed 22 people as their body was shifted from a normal pattern to that of a night-shift worker.
Blood tests showed that normally 6% of genes - the instructions contained in DNA - were precisely timed to be more or less active at specific times of the day.
Once the volunteers were working through the night, that genetic fine-tuning was lost.
Chrono-chaos
"Over 97% of rhythmic genes become out of sync with mistimed sleep and this really explains why we feel so bad during jet lag, or if we have to work irregular shifts," said Dr Simon Archer, one of the researchers at the University of Surrey.
Fellow researcher Prof Derk-Jan Dijk said every tissue in the body had its own daily rhythm, but with shifts that was lost with the heart running to a different time to the kidneys running to a different time to the brain.
He told the BBC: "It's chrono-chaos. It's like living in a house. There's a clock in every room in the house and in all of those rooms those clocks are now disrupted, which of course leads to chaos in the household."
Studies have shown that shift workers getting too little sleep at the wrong time of day may beincreasing their risk of type-2 diabetes and obesity.
Others analyses suggest heart attacks are more common in night workers.
Prof Dijk added: "We of course know that shift work and jet lag is associated with negative side effects and health consequences.
"They show up after several years of shift work. We believe these changes in rhythmic patterns of gene expression are likely to be related to some of those long-term health consequences."
Prof Hugh Piggins, a body-clock researcher from the University of Manchester, told the BBC: "The study indicated that the acute effects are quite severe.
"It is surprising how large an effect was noticed so quickly, it's perhaps a larger disruption than might have been appreciated."
He cautioned that it was a short-term study so any lasting changes are uncertain, but "you could imagine this would lead to a lot of health-related problems".
Related Stories
SON: "Daddy, may I ask you a question?"
DAD: "Yeah sure, what is it?"
SON: "Daddy, how much do you make an hour?"
DAD: "That's none of your business. Why do you ask such a thing?"
SON: "I just want to know. Please tell me, how much do you make an hour?"
DAD: "If you must know, I make £20 an hour."
SON: "Oh! (With his head down).
SON: "Daddy, may I please borrow £10.00?"
The father was furious.
DAD: "If the only reason you asked that is so you can borrow some money to buy a silly toy or some other nonsense, then you march yourself straight to your room and go to bed. Think about why you are being so selfish. I work hard everyday for such this childish behavior."
The little boy quietly went to his room and shut the door.
The man sat down and started to get even angrier about the little boy's questions. How dare he ask such questions only to get some money?
After about an hour or so, the man had calmed down, and started to think:
Maybe there was something he really needed to buy with that £10 and he really didn't ask for money very often. The man went to the door of the little boy's room and opened the door.
DAD: "Are you asleep, son?"
SON: "No daddy, I'm awake".
DAD: "I've been thinking, maybe I was too hard on you earlier. It's been a long day and I took out my aggravation on you. Here's the £10 you asked for."
The little boy sat straight up, smiling.
SON: "Oh, thank you daddy!"
Then, reaching under his pillow he pulled out some crumpled up notes. The man saw that the boy already had money, started to get angry again. The little boy slowly counted out his money, and then looked up at his father.
DAD: "Why do you want more money if you already have some?"
SON: "Because I didn't have enough, but now I do.
"Daddy, I have £20 now. Can I buy an hour of your time? Please come home early tomorrow. I would like to have dinner with you."
The father was crushed. He put his arms around his little son, and he begged for his forgiveness. It's just a short reminder to all of you working so hard in life. We should not let time slip through our fingers without having spent some time with those who really matter to us, those close to our hearts. Do remember to share that £20 worth of your time with someone you love? If we die tomorrow, the company that we are working for could easily replace us in a matter of days. But the family and friends we leave behind will feel the loss for the rest of their lives. And come to think of it, we pour ourselves more into work than to our family.
Some things are more important.
DAD: "Yeah sure, what is it?"
SON: "Daddy, how much do you make an hour?"
DAD: "That's none of your business. Why do you ask such a thing?"
SON: "I just want to know. Please tell me, how much do you make an hour?"
DAD: "If you must know, I make £20 an hour."
SON: "Oh! (With his head down).
SON: "Daddy, may I please borrow £10.00?"
The father was furious.
DAD: "If the only reason you asked that is so you can borrow some money to buy a silly toy or some other nonsense, then you march yourself straight to your room and go to bed. Think about why you are being so selfish. I work hard everyday for such this childish behavior."
The little boy quietly went to his room and shut the door.
The man sat down and started to get even angrier about the little boy's questions. How dare he ask such questions only to get some money?
After about an hour or so, the man had calmed down, and started to think:
Maybe there was something he really needed to buy with that £10 and he really didn't ask for money very often. The man went to the door of the little boy's room and opened the door.
DAD: "Are you asleep, son?"
SON: "No daddy, I'm awake".
DAD: "I've been thinking, maybe I was too hard on you earlier. It's been a long day and I took out my aggravation on you. Here's the £10 you asked for."
The little boy sat straight up, smiling.
SON: "Oh, thank you daddy!"
Then, reaching under his pillow he pulled out some crumpled up notes. The man saw that the boy already had money, started to get angry again. The little boy slowly counted out his money, and then looked up at his father.
DAD: "Why do you want more money if you already have some?"
SON: "Because I didn't have enough, but now I do.
"Daddy, I have £20 now. Can I buy an hour of your time? Please come home early tomorrow. I would like to have dinner with you."
The father was crushed. He put his arms around his little son, and he begged for his forgiveness. It's just a short reminder to all of you working so hard in life. We should not let time slip through our fingers without having spent some time with those who really matter to us, those close to our hearts. Do remember to share that £20 worth of your time with someone you love? If we die tomorrow, the company that we are working for could easily replace us in a matter of days. But the family and friends we leave behind will feel the loss for the rest of their lives. And come to think of it, we pour ourselves more into work than to our family.
Some things are more important.
Never mind let's chuck in flexible hours as well, what family life
ReplyDelete