A new study has identified two genes that may reduce gastric cancer.
When people do not drink enough green tea, those two genes can become damaged by DNA methylation.
The two genes are CDX2 or homeobox transcription factor, and BMP-2 or bone morphogenetic protein 2. They involve chemical pathways that are related to gastric cancer.
The researchers tested DNA methylation of these two genes as well as four other genes. After examining gastric cancer patient's lifestyles, they found a significant association between decreased green tea and increased DNA methylation damage of the two genes. The less green tea, the greater the damage.
In addition, they found that increased physical activity also provided DNA protection to the genes CACNA2D3 or calcium channel-related gene (Yuasa Y, DNA methylation status is inversely correlated with green tea intake and physical activity in gastric cancer patients, International Journal of Cancer, December 2008).
A previous study also confirmed the protective relationship between green tea and cruciferous vegetables in the diet against DNA methylation.
In particular, a daily intake above 7 cups of green tea showed significant reduction of DNA methylation and this protection was further enhanced by regular consumption of cruciferous vegetables like broccoli, cauliflower, cabbage, kale, Brussels sprouts, collard greens, and bok choy (Yuasa Y, Relationship between CDX2 gene methylation and dietary factors in gastric cancer patients, Carcinogenesis, January 2005).