If you’re a woman awaiting her period and spending a lot of time in the summer sun right now, then don’t be alarmed if you’ve suddenly developed “kankles” and gained mysterious weight overnight.

Ask The Expert: I’m Cycling Loads And Watching My Diet but Gaining Weight

Water retention – called ‘oedema’ by medical professionals – occurs when fluid is not properly removed from body tissue. It can be a reaction to hot weather, intense exercise, or changes in hormones during a woman’s menstrual cycle.

It is possible to gain up to 5 pounds as a result of water retention. Gaining 1-2 kilograms when you’re sweltering and want to be feeling flash in your best summer clothes, or awaiting your period, might seem like some sort of cruel joke from Mother Nature, but you don’t have to put up with it.