The heat increases the risk of dehydration. Our body needs more water and mineral salt.
Start your day by drinking two glasses of water and keep drinking at each meal, as well as before and after your workout. It is a good habit to bring a bottle of water always with you in case you need to walk long distances or if you need to take public transports.
Fruit also helps to reintegrate mineral salt. Have a light lunch, try to avoid carbohydrates more difficult to digest, and replace them with vegetables or fruit…a fruity ice cream can be an option!