A review of 12 published studies and more than one million subjects.
The cruciferous vegetable family, including broccoli, cabbage, and kale, remains a target of much cancer research. Because cancer comes in many forms, a team of Chinese researchers is looking for a particular connection between cruciferous vegetables and kidney cancer risk.
Reporting in the journal PLOS One, researchers from Shangdong University and the Shangdong Weifang People’s Hospital reviewed 12 cohort and case-control studies on cruciferous vegetable intake and renal cell carcinoma, the most common form of kidney cancer. In compiling data on more than 1 million subjects, and more than 5000 cases of kidney cancer, the researchers concluded that high intake of these vegetables is inversely associated with kidney cancer-but only for Americans. Data was not so convincing for Europeans, for example.
The results are subject to much interpretation and are likely influenced by a host of other factors, including age, lifestyle, and gender. Even cooking methods can influence the cancer-fighting status of cruciferous vegetables by increasing (steaming) or decreasing (microwaving) the bioavailability of key compounds. To better elucidate any association between these foods and cancer risk, future studies will have to consider all of these variables more closely.