As Europe emerges from another intense heatwave, the British science magazine New Scientist has dedicated its September 5 edition to exploring how humans can adapt to increasingly frequent and extreme heat. The cover story, written by journalist Alice Klein, examines the concept of "seasonal acclimatization," a natural process by which the body gradually adjusts to higher temperatures over time. This adaptation helps people cope better with heat during the summer months, reducing the risk of heat-related illnesses and deaths, especially as the season progresses. Klein, who grew up in Australia, noticed a striking contrast during a video call with colleagues in the UK. While they were struggling with a recent peak temperature of 38°C, she found the heat more manageable. This observation sparked a discussion on how individuals perceive and react to heat differently, influenced by factors such as culture, environment, and personal experience. In Australia, where summer heat is expected, people mentally and physically prepare for high temperatures, which can make the experience less stressful. While acclimatization is a natural process, it does not rely on genetic factors that allow some people to tolerate heat better than others. Instead, experts suggest that regular physical activity is one of the most effective ways to improve the body's ability to handle heat. Exercise increases internal body temperature, which in turn helps the body adapt to high temperatures. For those who cannot exercise regularly, studies have shown that frequent sauna use can offer similar benefits in terms of heat adaptation. However, there are limits to how much the human body can adapt. If core body temperature rises beyond 43°C, it becomes fatal. As global temperatures continue to rise due to climate change, some regions may become too hot for human survival. While humans can adapt to a few additional degrees of heat, the article concludes, there is a clear boundary to how much we can withstand. The challenge, as Klein points out, is to find ways to stay within those limits as the planet warms.