Shark cartilage is said to be beneficial in the treatment more conditions including arthritis, psoriasis (allied to arthritis), rheumatism, eczema, acne, allergies and the most controversial cancer. It is said to inhibit tumor growth by inhibiting angiogenesis the formation of new blood vessels by growing them from old ones. This can lead to metastasis, or the spread of cancer between organs and also feed the cancer cells with blood.