Omega-3 fatty acids abundant in fatty fish like salmon and sardines could help protect your kidneys against cancer, a study by Karolinska Institutet in Stockholm suggests. The study of 61,433 women looked at fatty and lean fish consumption and the risk of kidney cancer and the finding were that those who ate high amounts of fatty fish had 44 percent less risk for developing the most common form of kidney cancer, renal cell carcinoma, than those who did not consume any fish.