Your immune system helps to fight off all diseases, including cancer. Having a good immune system is vital to cancer treatment because it will not only help you fight the tumor, but if the patient goes through chemotherapy, the immune system will be weakened. There are several vitamin supplements you can take which will help to boost your immune system and fight off the cancer.
Vitamin A
The main component of vitamin A is lycopene, which has been found to be an effective tool in battling prostate cancer. Beta carotene, which your body can convert to vitamin A, contains carotenoids which help to lower lung cancer risk. Lycopene and carotenoids are also antioxidants which clear the body and help the immune system fight off germs. Vitamin A can be found in such foods as beef, liver, shrimp, eggs and cheddar cheese. The beta-carotene version of vitamin A can be found in vegetables like carrots and sweet potatoes
Vitamin C
The benefits of vitamin C on the immune system have been known for a long time. Although, mostly used as an overall immune system booster, it also helps with various types of cancer, such as stomach, breast, esophageal and mouth. The vitamin helps the body repair itself and support blood vessel walls by aiding in the creation of collagen. This vitamin is found in mainly citrus fruits and citrus juices (but it is found in all fruits). It can also be found in potatoes, broccoli, bell peppers, tomatoes and Brussels sprouts.
Vitamin E
Also an antioxidant, vitamin E is a vital component for helping the immune system battle cancer. This vitamin battles unstable molecules and neutralizes them, freeing the immune system to fight against other illnesses. Vitamin E has been especially helpful when used against prostate cancer. This vitamin is found in a variety of foods including vegetable oils, nuts and whole grains.
Folic Acid
Folic acid is an important part of new cell creation. As more healthy cells are created, the body gets stronger and the immune system is able to work better. Taking daily doses of folic acid can help fight against colon and breast cancer. Folic acid is found in fortified grains and cereals, asparagus, okra, spinach, turnip greens, broccoli, orange juice and tomato juice.


