1. United States
2. N.Y.
3. Letter

Zeitzer's study published Sept. 15 in the Proceedings of the National Academy of Sciences compared permanent standard time, permanent daylight saving time and shifting biannually. Shifting is the worst for our health, says the team. Sticking with either permanent time would be better — and a permanent standard time would benefit the most people, the scientists say. A permanent standard time would prevent approximately 300,000 strokes per year and result in about 2.6 million fewer people having obesity, according to the study. Sticking with DST permanently would accomplish about two-thirds of that effect.