Although many people think of fats as inherently bad, the truth is that omega-3 fatty acids benefit the body in many different ways, even in the prevention and treatment of cancer. Omega-3 fatty acids can work to reduce inflammation in the body, thus cutting down on oxidative stress that promotes the development of cancer. Furthermore, omega-3s act as antioxidants and boost the strength of the immune system to prevent lymphoma or any other form of cancer from taking hold of your body. Omega-3s are found in high concentrations within salmon, tuna, eggs, peanut butter, soy milk and yogurt.