Sunday, March 11, 2012

Hello Summertime!.. Owls Beware

Environment can significantly affect human health. And the risks are not limited to air pollution, seasonal allergies, tainted water or chemicals in food. Our life dramas are set against the backdrop of world events that contribute to environmental health too, to a lesser or greater extent.

How does springing clocks forward affect our lives?

Hopefully, not much financially. Despite earlier predictions that average stock market returns are likely to be lower on Mondays following time changes (Kamstra et al, 2000), unbiased modeling techniques in later studies proposed that markets are not really influenced by this event (Berument et al., 2010). So we can all sleep sound tonight.

Daylight savings time (DST) will make some of us a little bit more active. By about 2%, as measured by scientists in  Indiana (Holmes et al., 2009). It will lead to a 3% drop in crime, as estimated by the Home Office in UK. So we have something to look forward to.

Still, as we are going to loose 1 hour of sleep, would it not affect our mood, our attention and the ability to work productively? Would it increase the probability of being involved in health-related catastrophes? What about traffic accidents? Some studies suggest they will increase (by 8-17% according to Stanley Coren), while others say there will be no impact or even less accidents during DST transition (if 1 day or week before is compared to 1 day/week after, see articles by Ferguson, Coate, Lahti). The results about occupational accidents and hospitalizations are also inconsistent (Janszky, Lahti).

But there was one result that scientific studies from all over the world had in common:  the impact of DST transition was different on larks and owls. And night owls were the ones that suffered the most, during spring transitions - in Finland, Germany, Korea, Russia and everywhere else.

So let's enjoy the extra hour of sunshine. And if you are a morning lark, bear with the sleepiness of night owls  - they'll need more time to adjust.

Aurametrix is an advanced analysis tool that correlates our symptoms, reactions and feelings with  environmental factors such as weather, air, pollen and time transitions.


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