As discussions grow around the relevance of daylight saving time, experts are raising new concerns about its potential impact on human health. Beyond the inconvenience of adjusting clocks twice a year, recent findings suggest that the disruption to our internal body rhythms could have serious consequences — including higher risks of obesity, cardiovascular problems, and even stroke.
Daylight saving time, designed to maximize daylight hours during certain months, forces millions of people to adjust their natural sleep cycles abruptly. This seemingly small shift in time can trigger a cascade of physiological reactions, as the human body’s circadian rhythm — the 24-hour internal clock — struggles to realign with the new schedule.
Sleep Disruption and Weight Gain Connection
Sleep plays a critical role in maintaining metabolism, hormone regulation, and appetite control. When sleep is disturbed, even by an hour, the balance of hunger-related hormones such as leptin and ghrelin is affected. This imbalance can lead to overeating, sugar cravings, and a slower metabolism — all contributing to gradual weight gain over time.
People who experience ongoing sleep deprivation are also more likely to engage in late-night snacking and irregular eating habits, further straining the body’s ability to process calories efficiently. The biannual time changes associated with daylight saving can therefore act as a repeated stressor, making it harder for individuals to maintain a healthy weight in the long term.
Increased Stroke and Heart Disease Risk
The body’s cardiovascular system is highly sensitive to disruptions in routine, especially sleep and exposure to natural light. Studies have observed spikes in stroke and heart attack cases shortly after the start of daylight saving time. This is often attributed to increased stress levels, higher blood pressure, and impaired vascular function caused by the loss of sleep and circadian misalignment.
Even minor changes in sleep patterns can elevate inflammation and stress hormones like cortisol, both of which contribute to the risk of hypertension and heart disease. The first few days following a clock change can be particularly dangerous for individuals with existing cardiovascular conditions.
Why Ending Daylight Saving Time Could Improve Public Health
Eliminating daylight saving time could help stabilize people’s sleep schedules, allowing the body to function more consistently throughout the year. A fixed time system supports better alignment with the natural daylight cycle, improving energy levels, mental alertness, and overall health.
Consistent sleep patterns enhance hormonal regulation, reduce appetite fluctuations, and support healthier metabolic processes. In turn, this could help combat obesity rates and lower the likelihood of serious conditions such as stroke and heart disease.
The Road Ahead: A Shift Toward Healthier Time Policies
Many regions around the world are reconsidering the necessity of daylight saving time, with growing evidence suggesting that its health risks outweigh the benefits. A permanent standard time not only simplifies daily life but also aligns better with biological needs.
By prioritizing stable sleep and natural light exposure, societies could experience improved public health outcomes — fewer strokes, reduced obesity, and lower stress levels. Ending daylight saving time may thus represent not just a shift in policy, but a step toward a healthier, more balanced life for millions of people.
