A study presented in proceedings of the National Academy of Sciences USA indicates that broccoli grown under the right conditions contains SulfiraphaneGlucoSinolate a substance that may boost the body's natural defense systems against cancer and even kill cancer cell. But you would have to eat pounds of broccoli to get enough SCG to be effective. Continued food research by John Hopkins University Baltimore and the usda however found that three-day-old broccolis seedling contain a concentrated amount of scg-20 times the amount found in broccoli-so only an ounce provides the same benefits.