Scientists Show How Certain Vegetables Combat Cancer

While it has been known for some time that eating cruciferous vegetables, such as broccoli, cauliflower, and cabbage, can help prevent breast cancer, the mechanism by which the active substances in these vegetables inhibit cell proliferation was unknown — until now.

Scientists in the UC Santa Barbara laboratories of Leslie Wilson, professor of biochemistry and pharmacology, and Mary Ann Jordan, adjunct professor in the Department of Molecular, Cellular, and Developmental Biology, have shown how the healing power of these vegetables works at the cellular level. Their research was published in the journal Carcinogenesis.

"Breast cancer, the second leading cause of cancer deaths in women, can be protected against by eating cruciferous vegetables such as cabbage and near relatives of cabbage such as broccoli and cauliflower," said first author Olga Azarenko, who is a graduate student at UCSB. "These vegetables contain compounds called isothiocyanates which we believe to be responsible for the cancer-preventive and anti-carcinogenic activities in these vegetables. Broccoli and broccoli sprouts have the highest amount of the isothiocyanates.

"Our paper focuses on the anti-cancer activity of one of these compounds, called sulforaphane, or SFN," Azarenko added. "It has already been shown to reduce the incidence and rate of chemically induced mammary tumors in animals. It inhibits the growth of cultured human breast cancer cells, leading to cell death."

Other studies have confirmed the protective benefits of these vegetables for other types of cancer as well, such as:

Bladder cancer – Researchers found that the higher the intake of cruciferous vegetables, the lower the risk of bladder cancer in men

Lung cancer – Researchers found that men with detectable amounts of isothiocyanates in their bodies had a 36 percent lower chance of developing lung cancer over 10 years

Prostate cancer – This study, published in PLoS ONE in 2008, discovered that just a few additional portions of broccoli each week could protect men from prostate cancer

How Many Vegetables Do You Have to Eat to Reap These Benefits?
Previous studies have indicated that people who consume more than one portion of cruciferous vegetables per week are at lower risk of prostate cancer. In the PLoS study, the participants ate four extra servings of broccoli per week for one year.

The researchers collected tissue samples over the course of the study and found that the men who ate broccoli showed hundreds of beneficial changes in genes known to play a role in fighting cancer!

That’s pretty impressive. What’s even more impressive is the fact that you don’t have to make that drastic of a change to reap the benefits. After all, one serving of broccoli equates to about two spears. So we’re only talking approximately 10 spears a week. That’s it!

Sources:
Science Blog December 23, 2008
Carcinogenesis December 2008; 29(12):2360-8