Immune System and Cancer Prevention: Galia melons are packed with nutrients that can protect your body from illness, including high levels of vitamin C, which stimulates the immune system, vitamin A, which acts as an antioxidant, as well as carotenoids and bioflavonoids, which also act as antioxidants. These components eliminate or neutralize free radicals, which can cause cancer. Galia melons contain organic compounds that have been directly linked to reducing lung, oral, colon, and breast cancer.