Not changing the time in summer or winter in the US would reduce strokes and obesity, according to a study
If the United States did not change the time twice a year, there would be a lower incidence of obesity and strokes. This is the conclusion of a study by Stanford University (USA) published in PNAS that compared how three different time policies — permanent standard time (winter), permanent daylight saving time, and biannual time changes — could affect circadian rhythms and the health of the population. By modelling light exposure, circadian impacts and health characteristics county by county, the researchers estimate that permanent standard time would prevent about 300,000 cases of stroke per year and reduce the number of people with obesity by 2.6 million, compared to biannual changes. Permanent daylight saving time would also be positive, although with a smaller impact.