New data demonstrating a DNA protective agent was present in at least some fruits and vegetables found that the agent was heat sensitive and determined it was not vitamin C. This was confirmed in a study that tried vitamin C directly and found no effect on DNA protection and repair of DNA strand breaks.
The carotenoid beta cryptoxanthin, found primarily in citrus, seems to be at least one candidate. If you expose cells to a mutagenic chemical, you can cause physical breaks in the strands of DNA, but in less than an hour, our DNA repair enzymes can weld most of our DNA back together. But if you add some of that citrus phytonutrient, you can effectively double the speed at which the DNA is repaired. But this is all just cells in a petri dish, what about in a person?
If you have people drink a glass of orange juice and draw their blood two hours later, the DNA damage you can induce with an oxidizing chemical drops, whereas if they just had like orange Kool-Aid, it didn’t help.
So, do people who eat more fruit walk around with less DNA damage? Yes, particularly in women. Does this actually translate into lower cancer rates? Yes, citrus alone is associated with a 10% reduction in odds of breast cancer.
Given to newly diagnosed breast cancer patients, citrus phytonutrients were found to concentrate in breast tissue, though many complained of “citrus burps” due to the concentrated extract they were given; so, researchers evaluated topical application as an alternative dosing strategy, recruiting women to apply orange flavored massage oil to their breasts daily. This request was met with excellent compliance, but it didn’t work. We actually have to eat our food.
Why not just take carotenoid supplements to boost our DNA repair? Because it doesn’t work. Although dietary supplements did not provoke any alteration in DNA repair, dietary supplementation with carrots did. This suggests that the whole food may be important in modulating DNA repair processes.
Though orange juice consumption was found protective against childhood leukemia, it was not found protective against skin cancer. However, the most striking feature was the protection purported by citrus peel consumption. Who eats orange peels? Lots of people evidently. Just drinking orange juice may increase the risk of the most serious type of skin cancer. Daily consumption was associated with a 60% increase in risk; so again, better to stick with the whole fruit. And you can eat citrus extra-whole by zesting some of the peel into your dishes.
Featured Photo, Recipe and Article: Activate Lemon’s Hidden Anti-Cancer and Anti-Inflammation Powers by Freezing Them Like This
About Michael Greger M.D.Michael Greger, M.D., is a physician, author, and internationally recognized professional speaker on a number of important public health issues. Dr. Greger has lectured at the Conference on World Affairs, the National Institutes of Health, and the International Bird Flu Summit, testified before Congress, appeared on The Dr. Oz Show and The Colbert Report, and was invited as an expert witness in defense of Oprah Winfrey at the infamous “meat defamation” trial. Currently Dr. Greger proudly serves as the Director of Public Health and Animal Agriculture at the Humane Society of the United States.