With temperatures potentially reaching up to 40C this week, here are five foods recommend by experts to help stay cool and healthy...Watermelon, comprising over 90 per cent water, is excellent for hydration and provides vitamins C and A, along with “electrolytes such as potassium”, according to Sejal Jacob, a registered dietitian and Nutritionist Resource member. Tomatoes are “very water-rich”, offering a "nice, light, refreshing food that can really help with hydration," Jacob says. Greek yoghurt is noted by Jacob for its high water content and, when containing live bacteria, offers probiotic benefits. Homemade ice lollies are suggested as a cooling and refreshing treat by Kirsty Wood, a registered dietitian and Nutritionist Resource member. Simply blend fruit with coconut water or yoghurt and a touch of sweetener before freezing.Cucumber, with approximately 96 per cent water, is "one of the most hydrating foods you can reach for when it gets hot," Wood says. It also supplies vitamin K, silica, and potassium, which are beneficial for cardiovascular health. In fullExperts reveal best foods to eat during UK heatwave to stay cool and healthy