Flashback Friday: Which Fruits and Vegetables Boost DNA Repair?

In light of strikingly consistent observations from many population-based studies, there can be little doubt that the habitual consumption of diets high in fruits and vegetables helps to reduce the risk of development of degenerative diseases, including many types of cancers. Not satisfied with just telling people to eat their fruits and veggies, scientists want to know the mechanism.

Fruits and vegetables are not just vehicles for antioxidants; they contain innumerable phytonutrients that can boost our detoxification enzymes, modulate gene expression, and even repair DNA.

Until fairly recently, it was generally assumed that functions as important as DNA repair were unlikely to be readily affected by nutrition. But if you compare identical twins to fraternal twins, only about a half to three quarters of DNA repair function is genetically determined; the rest we may be able to control.

It is estimated that, on average, there are 800 incidents of DNA damage in our bodies per hour. That’s 19,000 hits to our DNA every day. And that DNA damage can cause mutations that can give rise to cancer—if not repaired.

Thankfully, the regulation of DNA repair may be added to the list of biological processes that are influenced by what we eat—and, specifically, that this might constitute part of the explanation for the cancer-preventive effects of many plant-based foods.

Any plants in particular? Nine fruits and vegetables were tested to see which was better able to boost DNA repair: lemons, persimmons, strawberries, oranges, choy sum (which is like skinny bok choy), broccoli, celery, lettuce, and apples. Which ones made the cut? Lemons, persimmons, strawberries, apples, broccoli, and celery each conferred DNA protection at very low doses.

Here’s what lemons could do, for example. Cut DNA damage by about a third. Was it the vitamin C? No, removing the vitamin C from the lemon extract did not remove the protective effect. However, if you boiled the lemon first for 30 minutes, the effect was lost.

To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video. This is just an approximation of the audio contributed by Katie Schloer.

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Images thanks to lightwise / 123rf, PublicDomainPictures / Pixabay, Evan-Amos / Wikimedia Commons, Olegivvit / Wikimedia Commons, Donnawetta / Pixabay, PublicDomainPictures / Pixabay, kattebelletje / Flickr, Fir0002 / Wikimedia Commons, Popolon / Wikimedia Commons, Selena / Wikimedia Commons and Silberfuchs / Pixabay