Overview

• Deputies approved the time‑change bill 151–66 with 8 abstentions, advancing a plan to set UTC‑4 in winter and authorize a return to UTC‑3 in summer.
• The measure would require Argentines to set clocks back one hour if it becomes law, with specific switch dates to be defined by the Executive.
• Chronobiologists argue the change would align civil time with solar time—most of the country maps to UTC‑4 and the far west to UTC‑5—improving morning light exposure, sleep and school performance.
• Energy savings remain disputed, with analyses of the 2007–2009 regime finding the prior shifts did not consistently reduce consumption and in some cases slightly increased it.
• Specialists warn that any abrupt clock changes can trigger short‑term health effects comparable to jet lag, including sleep disruption and higher risks of accidents and cardiovascular events.