Limes contain limonoid, a compound believed to have anti-carcinogen effects. These compounds are thought to help prevent skin, mouth, stomach, breast, lung and other types of cancer. An article published in the "Journal of Agricultural and Food Chemistry" noted that limonin has been proven to induce cancer cell death. Limes are also a potent source of antioxidants, particularly vitamin C. Antioxidants reduce the risk of cancer by preventing free radical damage to the cells and DNA. Limes may have anti-inflammatory properties that can slow the risk of chronic inflammation, another high risk factor for developing cancer.