Do you really know what’s in your go-to olive oil?  And what about that favorite coffee blend?  You may be scratching your head. “Um, olives and, well, coffee beans, obviously.” Not so fast.

Foods we eat every day are packed with things that aren’t supposed to be there—a practice known as “food fraud”—according to a new report from the United States Pharmacopeial Convention and their website FoodFraud.org. In order to reduce costs, unscrupulous companies illegally cut a primary ingredient with something less expensive. And the top 11 most frequently adulterated foods are things many of us eat every single day

1. Olive oil



We’d be hard-pressed to find another oil so healthy as that from olives. In all of its various virginities, olive oil lowers cholesterol, knocks out stomach bugs, and even makes skin glow. But that’s not the whole story. Researchers found that olive oil—yes, even the extra-virgin kind—is the most adulterated food, usually cut by hazelnut oil. (Sound good to any nut-allergy sufferers out there?) Other imposter ingredients include corn oil, sunflower oil, peanut oil, vegetable oil, soybean oil, palm oil, and walnut oil.

More from Prevention: How To Recognize a Nut Allergy

2. Milk



If you think that milk in your coffee comes from a cow, you might be mistaken.  Turns out, there may be a veritable zoo of producers in your carton. Sheep's milk has been found to be cut with bovine milk, and buffalo milk with goat-antelope milk.  Milk was also adulterated with reconstituted milk powder, urea, and rennet. But wait, there’s more! Milk was even cut with something called “fake milk”: oil, urea, detergent, caustic soda, sugar, salt, and skim milk powder. We’re not sure that does a body good…

More from Prevention: 7 Grossest Things In Your Food

3. Honey



Honey is one of our main squeezes for its healing antioxidants and downright deliciousness. But it’s also one of the most common fraudsters. You may also find sugar syrup, corn syrup, fructose, glucose, high-fructose corn syrup, beet sugar, and “honey from a non-authentic geographic origin” in that bottle—rendering it what we’ll call not-honey. Some honey is also likely laced with illegal Chinese antibiotics from abroad and heavy metals, according to Food Safety News.

4. Saffron


Saffron is the world’s most expensive spice , so its place on this list shouldn’t come as a surprise.  What is a surprise is all the stuff sometimes mixed with it. Inside those tiny, astronomically priced bottles of saffron, scientists have found glycerin, sandalwood dust, tartrazine (a yellow dye linked to hyperactivity in children and lupus); barium sulfate (a fluid mainly used in oil well drilling); and borax.

More from Prevention: Top 10 Most Healing Herbs

5. Orange juice

Orange Juice

Orange juice is no stranger to repulsive adulterants like illegal fungicide, and now, here are a few more reasons not to trust anything you don’t squeeze from the fruit: OJ has been shown to host unlisted lemon juice, mandarin juice, grapefruit juice, high fructose corn syrup, paprika extract, and beet sugar as some of its uninvited guests.

6. Coffee


Nothing starts a morning right like a fresh-brewed cup of…twigs? Believe it or not, researchers have found them in coffee, along with roasted corn, ground roasted barley, and even roasted ground parchment. Adulterants in instant coffee are every bit as sneaky; they include chicory, cereals, caramel, more parchment, starch, malt, and figs.

7. Apple juice


Apple juice may conjure the innocence of youth, but sometimes its ingredients are downright guilty. Grape juice, high fructose corn syrup, pear juice, pineapple juice,raisin sweetener, fig juice, fructose, and malic acid have all been detected in apple juice—or perhaps more accurately known as mystery apple soup.

More from Prevention: The Body Fat that Makes You Thinner?

8. Tea


Researchers found that tea has been polluted with leaves from other plants, color additives, and even colored saw dust. How's that for a wake-up call?

9. Fish


In December 2012, the conservation group Oceana found that 39 percent of seafood samples bought in New York City were actually mislabeled as a different species. The fake fish phenomenon is apparent in records, too. The U.S. Pharmacopeial Convention found that fish labeled "white tuna" and "butterfish" are often a fish called escolar, which is banned in Italy and Japan for its waxy esters, which may cause food poisoning. Benign-sounding "monkfish" is even sometimes a disguise for puffer fish, which has caused tetrodotoxin poisonings in the U.S., the group said.

10. Clouding agents


Two glasses of healthy juice - Beet, Apple, Carrot, Ginger and Orange, Apple, Pineapple. Ingredients in the background.

That glass of fruit juice might look fresh-squeezed, but chances are, it isn't. Fraudulent replacements for palm oil and other acceptable food ingredients are rampant: the U.S. Pharmacopeial Convention found 877 food products from 315 companies with fake clouding agents. What's the most common fraudster? Meet the plasticizer Di(2-ethylhexyl) phthalate (DEHP), a chemical that's been linked with cancer and thwarted reproductive development in children, the group says.

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