Citrus and Green Tea Daily Offer Anticancer Protection
An apple a day may keep the doctor away, but experts now say that citrus and green tea every day may help keep cancer away as well. Daily consumption of oranges, grapefruit, and other citrus, along with a cup of green tea may reduce the risk of cancer, according to a new study from Japan.
Citrus and green tea are both popular in Japan, and the researchers, led by Wen-Qing Li from Tohoku University Graduate School of Medicine, noted that “these findings suggest that a possible joint effect between them may have implications for public health.”
Benefits of Citrus and Green Tea
Citrus fruits are well known as nutritional powerhouses. In a 2009 Texas A&M University study entitled “Citrus Superfruits: Multiple Potential Health Benefits,” researchers explained that citrus are promoted commercially as functional foods because they contain many bioactive compounds such as phenolics, flavonoids, carotenoids, sterols, limonoids, vitamin C, and more.
The compounds found in citrus have potential anticancer properties, including demonstrated ability to fight colon cancer cell proliferation and promote cell suicide (apoptosis), and to inhibit growth of human breast cancer. Green tea contains the antioxidants catechins, which have also shown anticancer abilities.
New Citrus, Green Tea Study
Japanese researchers evaluated data regarding citrus and green tea consumption from 42,470 people (average age 59 years) in the Ohsaki National Health Insurance Cohort. After nine years of follow-up, 3,398 people had been diagnosed with cancer. Five categories of citrus consumptions were identified: never, occasionally, 1 to 2 times weekly, 3 to 4 times weekly, and daily.
Daily consumption of citrus was associated with an 11 and 14 percent reduction in the incidence of all types of cancer for both men and women, respectively, when compared with never having citrus. Researchers also noted that drinking one cup of green tea daily along with the citrus boosted the anticancer effect to 17 percent.
The study’s authors point out laboratory data indicate that citrus compounds like lycopene, lutein, hesperidin, and limonoids have shown anticancer potential against both pancreatic and prostate cancer. Li emphasized that “clinical trials are ultimately necessary to confirm the protective effect of citrus consumption against cancer.” The contribution of green tea also needs to be explored.
Li W-Q et al. International Journal of Cancer 2010; 127: 1913-22
Patil BS et al. Citrus superfruits: multiple potential health benefits. April 2, 2009, Texas A&M University.