“Cool as a cucumber”" isn’t just a catchy phrase. The inner temperature of a cucumber can be up to 20 degrees cooler than the outside air.
Cucumber has 96% water content that is more nutritious than regular water, which helps in keeping the body hydrated and regulating body temperature.
The cucumber is originally from India where it has been cultivated for over 3,000 years. There is a reference to people eating cucumbers in the ancient story of Gilgamesh.
The flavor comes from their seeds. Medium-sized cucumbers with soft small seeds have better flavor.