How hot weather harms human health

Climate change leads to extreme temperatures that can make you sick or kill you

Know what extreme heat and heatwaves are

Your health can be affected by isolated days of extreme heat (maximum temperature of 35°C or more) or during heatwaves. Heatwaves are defined as three consecutive days when the highest temperature is 5°C above the mean maximum for the hottest month in that area

What heat can do to you

Extreme heat can cause dehydration, heat cramps and heat exhaustion. It can also cause heat stroke which manifests as damage to the brain, kidneys and other organs. This can be fatal. Extreme heat can also affect mental health, including worsening of anxiety, irritability, interpersonal violence and gender-based violence

Disease and infection

Excessive heat indirectly influences health through outbreaks of food and waterborne infections. It enlarges areas affected by malaria and other infections carried by insects and organisms

Food insecurity and malnutrition

Extreme heat increases evaporation from dams and rivers and damages crops, leading to hunger, malnutrition and higher food prices

Who is more vulnerable?

Some groups have higher exposure to heat or are more physiologically or socioeconomically vulnerable to heat stress: The elderly, infants and children are at the highest risk.

Pregnancy raises the vulnerability of women to heat exposure and has been linked to preterm birth and stillbirth. People with chronic medical conditions have limited ability to respond to heat stress

People living in poor households or who are homeless are at high risk — they may have limited access to water, fans and

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