Monday, March 12, 2007
Spring forward, falling back: Bad for your health?
When I was a kid, daylight-saving time was a glorious time of the year. It meant two things: warmer weather and more hours of schoolyard antics for me and my ball-playing buddies. I used to look forward to it. It used to make me as happy as a vacation day from school.

Now as an adult, daylight-saving time means one thing: one less hour of precious sleep. As I groggily dragged myself out of bed, I just had to wonder: Can one less hour in bed affect my health?

First, I had to find out a bit more about daylight-saving time itself. After all, it seems like a misnomer. You can't really save daylight. We can change, wind or even break the clocks as much as we want, but I'll still get about 12 hours of sunlight in New York today. One of the main purposes for DST is energy conservation. The idea is that daylight should coincide with peak activity times. So, we spring forward so that we don't sleep through that early morning daylight. Also, it gives us more natural light in the evenings. With the clocks moving forward, we use less energy, through acts such as lighting our houses later at night.

How and when did DST all begin? Well, with politicians, of course. Germany was the first nation to enact it in 1915. These days approximately 70 countries worldwide observe DST. Almost all of the United States practices DST except for parts of Arizona and Indiana. In 1918, the U.S. Congress passed the first DST law, but repealed it a year later. In 1966, the Congress enacted the Uniform Time Act which established a uniform DST throughout most of the country. This year, with the Energy Policy Act of 2005 going into effect, DST started three weeks early.

Does all this temporal law-making affect our health? The answer is a definitive maybe. On the bright side, it could mean good news for your oral health. The additional amount of daylight could stimulate your body’s vitamin D production and strengthen your teeth and bones according a study in the Journal of Periodontology. A small 2006 Finnish study found that people who regularly sleep less than eight hours or who are more active at night have a much harder time adjusting to the DST change.

There has also been a good deal of research looking into DST and traffic accidents. The reviews are mixed. In the long-term, DST has been shown to save lives through reduced automobile crashes. The researchers say accidents decrease because more people are traveling during daylight hours and fewer are driving during the accident-prone nighttime. But in the short-term, a Canadian researcher found that springing forward is associated with a slight increase in the number of accidental car deaths. Stanley Coren of the University of British Columbia found a 6.5 percent to 8 percent rise on the Monday immediately following the time change. That's compared with no increases associated with the falling backward shift.

What do you think about daylight-saving time? Do you think it has any impact on our health? Is the practice useful to you? Do you think energy conservation is a direct result? Are there any harmful effects?
The real problem with springing forward is just the sleep loss on the first night, and that can be averted by setting the clocks and going to bed an hour earlier. Perhaps the short-term problems associated with DST really just indicate the larger problem of modern overscheduling: we lose an hour of sleep because we can't afford to lose an hour of anything else.
I was looking forward to waking up to sunshine and not driving to work in the dark. Maybe those who are in the more Southern States don't notice this but in North Dakota, the dark mornings driving to work during the winter, we can hardly wait for them to be over. Driving to work in the dark is long enough without moving DST earlier!
I think the Car Talk guys from NPR described daylight savings time the best when they said that it was a way that the government took an hour away from everyone in the Spring and gave it back in the Fall to the survivors.
I know the daylight hours don't make much difference to my energy consumption; most of the apartment is pretty dim even on a bright sunny day, so I have to turn on lights to see what I'm doing. I've also heard that statistically it doesn't really make any difference to people's energy consumption.

For night owls like me, springing forward is no fun. Sure, I can get in bed an hour earlier, but that just gets me an extra hour of tossing and turning and thinking about how tired I'm going to be in the morning.
This question can be approached in two ways: First, DST is very practical for energy conservation and for giving us more "waking" hours of daylight. Unfortunately, DST is an incredibly rude awakening to you body. Most of us do net get enough sleep to begin with. As a student, I am often up late completing homework, and losing an hour of sleep is nothing short of agitating. Our bodies to not adjust well to sudden shock, and springing forward can compromise everything from our productivity to our creativity to our immune system's ability to fight off viral infections. While DST is beneficial to society and lifestyle, and is very practical, we pay a price medically when an all-important hour of sleep is yanked from our grasp.
I love it, I love it, I love! I could go on and on about how I have always enjoyed DST from a small child to now ( I am 46 years of age). I have lived in Georgia, Tennessee, Virginia,Texas and Colorado. The sunshine makes me happy and I always feel so much better with more motivation in the spring, summer and fall. If I could always live in the DST frame, live would be more productive. Please let's not change it.
It works for me. Getting home while it is still sunny seems to give me the extra boost I need to go out and exercise after work.
A century ago when DST was initiated, lots more people worked outside, or in factories and mills with big windows letting in natural daylight. Now, most people work indoors where the lights are on during the entire workday, regardless of whether it is light outside. I find it very hard to believe that there are any significant energy savings from DST in the 21st century.
I am confused! There are studies showing people do not get enough sleep. We hear about the lack of sleep approximately 3-4 weeks before the start of DST.

The big question is who benefits from DST?

There are some problems with DST. Just to list a few, people schedules are disarray, people are put in harmful situations because they use public transportation early in the morning and the streetlights go off at a set time (even if it is dark outside).

So, again I ask who benefits from DST.
You have got to be kidding! I don't even KNOW anyone who doesn't like daylight savings time. I get most of my sunshine hours in the PM, not the AM, and since I suffer from SAD, the extra sunshine helps me tremendously. I don't know what all the bad publicity about the extra daylight savings time is about, but I and everyone I know what's it to be ALL YEAR ROUND!!!
I love DST and look forward to it every year. I am thrilled it started 3 weeks early! I find myself feeling depressed and lethargic when it gets dark early. During DST, I feel that my day wasn't completely used up at work. Additionally, the sun just makes me feel happy, energetic, and generally, more positive. I am much more pleasant during DST...and I know it's not all in my head.
As far as driving to work in the dark, so what? I would rather drive to work in the dark knowing it will soon be light, than drive home in the dark and god-forbid have a breakdown or something in the dark of night because it gets dark so EARLY after daylight savings time ends. I especially worry about kids on buses having breakdowns on the way home. In the morning it will get light, in the evening
it only gets darker. That's why it should be all year long.
One of the positive aspects of day-light savings time is the feeling of sunshine people get in the afternoon when they leave work. It feels good to leave work and see light out and bring back memories of summers past. Therefore, I think the long term impact of DST is chronic nostalgia.
As I grow older, I find that each year it takes more time to adjust! I made an effort to "prepare" for its onslaught with a sushi meal which is full of fish for more brain food. I will see if this helps and if it does, I will up my fish intake for a while at this time. Good Luck Everybody, Linda Helgeson, San Francisco, CA.
I think it is annoying. I would like to just leave the clocks alone so that you would not have to adjust 2 times a year.
DST, my pet peeve!! My body never adjusts and I rejoice when the country changes back to "real" time. How do you tell a cow that adjustments have to be made in milking time. Same principal.
I hate the change in time. It messes up my schedule -sleep and other. It messes up my daughter schedule. I think our biological clock does not like these changes - I am groggy as I can be in the morning, by the time my body adjusts to this change, new time change is about to come. It is like a jet lag. I do not think it is good for productivity in work. And the energy saver? Why to not switch the lights of when not in room, and other energy saving instead of forcing people to adjust the time for sleeping, waking up, for lunch, dinner? My body gets hungry at noon, then it is 11 am, then noon is always the same time of a day only the time on the clock is different. My body wants to sleep at certain time- when they move the time, I do not get enough sleep. And people who do not get enough sleep cannot perform in work as well, cannot pay attention on the road a well. Is the "energy" savings worth it? Again, I would rather educate peple how to save the energy different ways.
I think that in some cases daylight savings time can affect our health. I know just from my experience that when the time changes its hard for my body to adjust. We are now two days into the change and for the past two nights I have not slept well. I toss and turn and this is also affecting my husband's sleep patterns also. I do like have longer days because I work most of the day so I like to have sun light when I get of work. I belive that day light savings time def. has its pros and cons
I have to say, I'm not a fan of DST. I have enough trouble with waking up at 7AM on ST, now I'm still in bed 8AM on DST. I've pretty much set my body schedule to the sun, vs an alarm clock, but getting up with the sun, now means I'm ready for bed before I even leave the office.
I don't mind the springing forward, but why fall back? Why not have sunshine later in the evening all the time??
I welcome DST with disdain. Even more so now with more of it. All winter I wake easily to greet the day with energy. During DST, it's an hour earlier than my body wants to be up, and I cannot get to sleep earlier at night..therefore my health suffers due to less sleep. Headaches, eating wrong because I cannot eat breakfast that early. I believe it has to do with hormone levels like cortisone and dhea. Ours are set in stone for each time of day. When you mess with your sleep schedule, you are waking with different levels. What is natural is natural. When we mess with it, we pay.
I just love daylight savings time. Here in Toronto we have to get out of bed in the dark no matter what, in the fall and winter. But with DST it is great that we can come home when it is still daylight and don't feel like moles, always in the dark. Also, when the kids get out of school and they have a little more daylight.
Regular time is great for the farmers... but what percentage of the North American population are farmers in 2007? Very small I think. And what percentage of North Americans suffer from Obesity? I'm sure DST encourages after work and after school activities. I'm hoping it is extended to year round DST....
Deepti, Toronto, Canada
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