Can you cook a stir fry in water instead of oil?

[BmmnTmmmWmm]

l use about 30ml of vegetable oil in my stir-fry but l still feel as if it's slightly too fattening, plus l add some sauce into it as well (15ml of soy sauce.) l was just wondering whether you could cook it in water instead? Or is there any other types of oil that may be a bit healthier to use? Thanks!