If research indicates that a certain chemical is harmful to humans (or animals), it might seem like a no-brainer that food regulation agencies across the globe would all agree to ban it. But it’s not always that straightforward: Many studies don’t produce definitive results, and people don’t always agree on what constitutes “definitive results” anyway. So the U.S. Food and Drug Administration (FDA), the European Union’s European Food Safety Authority (EFSA), and other organizations have to make their own judgment calls—and, unsurprisingly, they often come to different conclusions. Here are seven food additives that the FDA has given its stamp of approval, but other countries have outlawed.

1. rbST

Somatotropin is a growth hormone found in humans and other animals that stimulates growth and development. In cattle, it’s aptly known as bovine somatotropin, or bST. If you inject cows with additional bST produced synthetically—called “recombinant bovine somatotropin” (rbST) or “recombinant bovine growth hormone” (rBGH)—they’ll produce more milk. But it often comes at a cost: Studies have shown that cows subjected to rbST have a much greater risk of lameness, infertility issues, and udder infections. It’s not clear what the risks may be for humans who drink milk or eat meat from rbST-injected cattle, and the FDA has deemed those products safe to consume. But rbST’s adverse effects on the cows themselves were a good enough reason for Canada and the European Union to outlaw it in 1999. It’s also not allowed in any American products certified USDA Organic.

2. Ractopamine

To plump up livestock with as much lean meat as possible before the slaughter, farmers often add ractopamine to their feed. It’s from a class of drugs known as beta-agonists, also used to relax muscles and open airways for asthma sufferers. Much like rbST, there’s still a lot of ambiguity surrounding ractopamine’s safety for human consumption. The FDA and other experts maintain that it’s fine; but some research has suggested that it may cause increased heart rates in humans [PDF]. It’s also been linked to increased rates of lameness and other issues in the animals themselves (especially pigs). In general, more research is needed, but the uncertainty has led the European Union to ban it altogether, and dozens of other countries—including China, Russia, Turkey, Egypt, and India—have done the same. The U.S. hasn’t followed suit, though certain American meat manufacturers have sworn off using it on their own in order to export meat products to China’s ractopamine-free market.

3. Olestra

Olestra-infused chips in their heyday.John Barr/Liaison/Getty Images

Procter & Gamble’s fat substitute olestra was common on shelves in the form of fat-free Pringles and Frito-Lay products during the late 1990s. Its infamous habit of causing “anal leakage” and interfering with the body’s vitamin absorption made it fall out of fashion after several years, but the FDA still allows it in snack foods (though manufacturers must add certain vitamins to olestra-containing products to offset the absorption issues). Canada and the UK, on the other hand, kept things simple by never OK’ing olestra in the first place.

4. Potassium Bromate

Potassium bromate helps flour rise and brightens the color of bread, but it’s also known to cause cancer in rats [PDF]. The possibility that it might cause cancer in humans, too, is enough to have landed it on the do-not-use list in China, Brazil, India, Canada, the UK, and the European Union. In the U.S., where the mindset is less “better safe than sorry” and more “innocent until proven guilty,” it’s permitted in bread products and malted barley.

5. Azodicarbonamide

Azodicarbonamide, or ADA, creates the gas bubbles that help make plastic products like yoga mats and shoes springy and lightweight. It has a similar effect on bread products by making dough fluffier and more durable (and, like potassium bromate, can also function as a whitening agent). ADA breaks down when it’s baked, and one of the resulting chemicals, semicarbazide, has been correlated with increased cancer rates in some rodents. The FDA claims that it poses no threat to humans when consumed at certain legal levels, and scores of recognizable brands have been known to use it in their products. But public pressure has led some companies—like Subway and Wonder Bread—to remove the additive from their foods in recent years. In the European Union, however, the ingredient has been banned outright for over a decade.

6. Red Dye 40 (And Other Synthetic Dyes)

Impressive dye job on these M&Ms.Spencer Platt/Getty Images

In 2007, researchers from the UK’s University of Southampton published a study suggesting that consumption of a mixture of certain synthetic food dyes—including Red No. 40 and Yellow No. 5—and the preservative sodium benzoate could increase hyperactivity and inattention in children. Though the study didn’t prompt an outright ban, the UK’s Food Standards Agency advised manufacturers to stop using those synthetic dyes, and you generally won’t find them in British foodstuffs these days. Within a few years, the European Union mandated that products containing the dyes carry a warning that consumption “may have an adverse effect on activity and attention in children.” In the U.S., manufacturers just have to mention artificial dyes in their lists of ingredients.

7. Brominated Vegetable Oil

The reason your citrusy soda tastes the same from beginning to end may be thanks to brominated vegetable oil (BVO), a mixture of bromine and vegetable oil that helps prevent the flavors from separating from the water. According to the Mayo Clinic, bromine has been known to cause skin irritation and neurological issues after chronic, long-term exposure—and it’s possible that drinking a couple liters of soda per day could produce some of the same symptoms. While the European Union and Japan have disallowed BVO completely, the FDA still permits diluted quantities in “fruit-flavored beverages.” That said, public backlash has succeeded in getting major American beverage manufacturers like PepsiCo and Coca-Cola to remove it from many products anyway.