Global warming can worsen health risks

While physical inactivity continues to pose mortal risks in the future, studies have highlighted that recent rise in global temperatures can cause severe heat stress on top of production and activity loss. As the burden mostly lies upon low- and middle-income countries like India, the government need to orient health policy priorities

Commuters braving heatwaves during a hot summer afternoon in Delhi (Photo | Express)

A study in the Lancet Global Health journal has cautioned that hotter climate could drive millions worldwide into physical inactivity by 2050, cause 7,00,000 more premature deaths a year and result in $3.68 billion in productivity losses. According to experts, physical inactivity is a major cause for diabetes, cardiovascular disease, obesity, certain cancers, muscle weakness, osteoporosis, poorer blood circulation, increased inflammation and mental health issues.

Another study, in the Environmental Research: Health journal, has underlined something we in India have experienced increasingly in recent years—humid conditions on the hottest days of the year considerably reduce physical activity in the tropics and subtropics. The Intergovernmental Panel on Climate Change projects that every 0.5°C rise in temperature increases the intensity, frequency and duration of heat-humidity extremes, with labour-productivity losses and health risks. If the global average rises by 2°C above the pre-industrial temperatures, more than a quarter of the world’s population could experience an extra month of severe heat stress each year compared to the 1950-79 average. Such shifts compress the number of thermally safe hours for exertion, eroding habitual physical activity and exacerbating inequalities where adaptive capacity is limited.

The burden is especially heavy on low- and middle-income countries where non-communicable disease mortality is already high. India, which faces diabetes as a major public health crisis, should particularly heed the caution. According to the Indian Council of Medical Research, as of 2024-25, over 10 crore Indians suffered from diabetes, while 13.6 crore were pre-diabetic.

The major risk factors for cardiovascular diseases, the leading cause of mortality in India, include diabetes, increasing consumption of high-fat, high-sugar and processed foods, tobacco and alcohol. In urban areas, poor air quality exacerbates the risks. The recent studies add global warming as another factor aggravating the situation.

WHO guidelines say adults up to age 65 should have at least 150 minutes of moderate or 75 minutes of vigorous physical activity per week. Given its disease burden, India cannot afford to ignore the probability of forcibly reduced physical activity. The central and state governments need to significantly increase focus on health and climate action to improve the quality of India’s human resources for the future.