DNA is safe to eat. RNA isn't bad either.


Have you eaten any DNA lately? My bet is that you’ve eaten lots of it. DNA is not only safe to eat, it’s present in many truly delicious foods.

For example, chocolate has loads of DNA. Ice cream also has DNA, plenty of it. And lest you think DNA is only in desserts, it’s also found in hamburgers, cheese, bread, all kinds of sushi, and a very long list of other foods. Want to know which foods are DNA-free? Keep reading.

(Aside: why am I explaining that DNA is safe? Scientists reading this might say of course it is, what’s the big deal? If you’re among those, you don’t need to read any further. But many people are afraid to eat DNA because they don’t know what it is, and the name sounds a bit scary. In fact, a study in 2016 found that 80% of Americans thought that foods containing DNA should have a warning label.)

DNA contributes pretty much nothing to the taste of your food, which is sort of obvious given that it’s found in so many different-tasting foods. That’s because flavors are a very complex combination of many, many ingredients, and DNA is just one small part of most foods. If you were to purify DNA and taste it all by itself, it would taste slightly salty. If you want to watch someone trying this for himself, check out this video:


So how do we know that DNA is present in so many different foods? The explanation goes like this: all living things–plants, animals, fungi, bacteria, and others–are composed of cells. Almost every cell in a plant or animal contains a copy of its genetic code, and that code is captured by DNA molecules. Think of DNA as a very, very long string of chemicals, or “bases.”

In rice, to choose just one example, each cell contains 12 chromosomes, and each chromosome is a long DNA molecule. The DNA strings in rice add up to about 430 million bases. So when you’re eating rice, you’re eating all of this DNA in every bite.

The wheat we use to make bread has even more DNA: every cell has about 16 billion bases. That’s 5 times more DNA than human cells have! But interestingly, the wheat we use to make pasta, called semolina or durum wheat, has only about two-thirds as much DNA as bread wheat (and only 14 chromosomes instead of 21). But I digress.

Thus any food that is derived from a plant or animal is almost certain to contain DNA, unless the food is processed so much that every cell from the original plant is removed or pulverized to bits, and the DNA is somehow removed (which normal food processing or cooking does not do). There’s no reason to remove the DNA, though, because it’s completely safe.

Pretty much every food that has DNA in it will also have RNA. RNA is safe to eat too! Some people have been concerned lately about RNA, which has been in the news frequently because it is used in two of the most effective Covid-19 vaccines, the ones from Pfizer/BioNTech and Moderna. Of course, injecting RNA into your arm is different from eating it, but both are very safe. (For more about RNA vaccines, see the article I wrote just a month ago, here.)

Now let’s answer a question I posed at the top: what foods don’t have DNA? The list is remarkably short:

  1. Salt
  2. Sugar*

Yep, that’s it. Salt is a mineral, so it doesn’t come from living things. And sugar is a simple molecule, C12H22O11, produced by plants such as sugar cane and sugar beets. The asterisk (*) next to sugar is there because unless the sugar is very pure, some DNA from the original plants is probably present, so even "pure" sugar might not be DNA-free.

And if you want to wash down that salt and sugar with a DNA-free drink, you can’t use coffee, tea, wine, beer, or fruit juice. All of them contain DNA.

Before I close, I should add that DNA stands for deoxyribonucleic acid. To some, the name is cause for concern: after all, “acid” can’t be good, right? Maybe we should call it “nuclein” instead; that was the name given to it by Friedrich Miescher, the Swiss scientist who first discovered DNA, in 1871.

Bottom line: DNA is in almost everything you eat, you’ve been eating it all your life, and there’s nothing to worry about.

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