Extending daylight could boost health, help planet

LONDON Fri Oct 29, 2010 7:41am EDT

The sun shines through the pillars of a memorial in Hyde Park, in London October 11, 2010. REUTERS/Luke MacGregor

The sun shines through the pillars of a memorial in Hyde Park, in London October 11, 2010.

Credit: Reuters/Luke MacGregor

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LONDON (Reuters) - Putting the clocks back in winter is bad for health, wastes energy and increases pollution, scientists say, and putting an end to the practice in northern areas could bring major health and environmental benefits.

Countries across Europe, the United States, Canada and parts of the Middle East mark the start of winter by ending Daylight Saving Time (DST) and putting their clocks back by an hour -- often in late October or early November -- a move that means it is lighter by the time most people get up to start their day.

But this also robs afternoons of an hour of daylight, and some experts argue that in more northern regions, the energy needed to brighten this darkness, and the limits it puts on outdoor activities are harming our health and the environment.

Leaving clocks alone as winter approaches would allow an extra hour of daylight in the afternoon and could boost levels of vitamin D as well as encourage people to exercise more.

In some countries, such as Britain and Russia, politicians are being asked to consider parliamentary bills suggesting it's time for a change.

"It must be rare to find a means of vastly improving the health and well-being of nearly everyone in the population -- and at no cost," said Mayer Hillman of the Policy Studies Institute in Britain, where a bill on DST is coming up for consideration in parliament soon. "And here we have it."

Almost half of the world's population has lower than optimal levels of vitamin D, often called the sunshine vitamin. Vitamin D deficiency is a well-known risk factor for rickets and evidence suggests it may increase susceptibility to autoimmune diseases.


Hillman conducted a study focused on Scotland, the northern-most part of Britain, which found that switching to Central European Time -- to Greenwich Mean Time plus one hour (GMT+1) in the winter and GMT+2 in the summer -- would give most adults 300 extra hours of daylight a year.

A "lighter later" campaign in Britain has gained support from many of the country's major sporting bodies.

Writing in the British Medical Journal on Friday, Hillman said research shows people feel happier, more energetic and have lower sickness rates in the longer, brighter days of summer, whereas moods and health decline during duller days of winter.

Dr. Robert Graham of Lenox Hill Hospital in New York said leaving clocks alone in winter should be considered to encourage people to get out more and get more exercise.

High rates of chronic illnesses such as diabetes, heart disease and obesity are caused in part by lack of exercise -- adults are advised to do 30 minutes moderate or vigorous activity a day, and children at least an hour.

"As a society we are always looking for accessible, low cost, little-to-no harm interventions," he said by telephone. "By not putting the clocks back and increasing the number of accessible daylight hours, we may have found the perfect one."

A study published earlier this year found that advancing clocks by an hour in the winter would lead to energy savings of at least 0.3 percent of daily demand in Britain.

Elizabeth Garnsey, one of the study's authors and an expert in innovative studies at Cambridge University, said this was equivalent to saving 450,000 metric tons of CO2 during winter alone.

(Editing by Paul Casciato)

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Comments (14)
Eideard wrote:
Parochial crap!

Try the same study in a land where air conditioning is used more often than heating systems.

Let’s break the world into different methods of constructing time zones – or state-by-state, province-by-province.

Egregious foolishness.

Oct 29, 2010 9:35am EDT  --  Report as abuse
kmreview wrote:
I’m with you Eideard. Year-round daylight savings time isn’t gonna help. The only thing it’s going to do is mess up the time zones even more than they already are and cause people to spend more. Because instead of using those extra hours of daylight to exercise or go out for a walk, people are gonna spend it shopping, going out to eat or keeping their A/Cs on a little while longer to rack up the electric bill.

Plus, the days get naturally shorter during the wintertime anyway. Daylight savings time has already been extended until November, and even here down south where it’s professed to be sunnier, when October rolls around, the sun sets by about 6:30, and it’s dark by 7 in spite of daylight savings time. So explain to me, first of all, how keeping daylight savings time during the winter is going to do anybody any good, and secondly, why the whole nation has to permanently set the clock forward an hour just because people up north need their vitamin D so badly. Why can’t they just take a One a Day like normal people? Or better yet, just freakin’ eat healthier!

Oct 29, 2010 11:08am EDT  --  Report as abuse
SuefromSault wrote:
Agree with kmreview and eideard!

You could do the same thing by having people start work at a more reasonable hour like 7:30 AM instead of 9!!

The real problem is that “daylight savings” is designed to give people “leisure” to be better consumers (of shopping malls, TV programs, and just plane junk). NONE of these have health benefits! (Except for the wallets of the sellers!)

Oct 29, 2010 11:59am EDT  --  Report as abuse
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