How often do you read the nutrition label on your dog’s bag of food? When reading the ingredient names, do you find yourself wondering, “What is this?” We already know pets improve our lives, but do we really know what’s in their food?

Luckily, the Food and Drug Administration (FDA) regulates pet food and provides a complete breakdown to help pet owners navigate pet food labels. According to the FDA, “the majority of ingredients with chemical-sounding names are, in fact, vitamins, minerals, or other nutrients.” However, opinions still vary on dog food ingredients.

Below, you’ll find the names that look the most scary on those labels — and whether you should worry about them.

Ethoxyquin

Approved as a pet food additive in 1959, ethoxyquin is a preservative that prevents fat in food from rancidity. The FDA allows trace amounts for human consumption, namely to preserve three spices — chili powder, paprika, and ground chili. But you could also find ethoxyquin used as a pesticide and rubber preservative.

Ethoxyquin came under fire in the 1990s for causing skin problems, cancer, and other health issues in dogs. For this reason, the FDA had manufacturers reduce the amount by half in dog food. 

Butylated hydroxyanisole

Butylated hydroxyanisole, more commonly known as BHA, is a preservative and found in foods such as butter, cereal and meat. Manufacturers also use BHA to make cosmetics, rubber, medicines, and food packaging.

Despite its common uses in the United States, BHA has been a controversial ingredient since being linked to cancer in rats. In fact, it’s such a controversial ingredient that Japan, the United Kingdom, and other European countries have banned it.

Butylated hydroxytoluene

Butylated hydroxytoluene, more commonly known as BHT, is a chemical preservative similar to BHA. Manufacturers use BHT to preserve freshness in many products, including cosmetics, embalming fluid, and jet fuel.

It was even an ingredient in cereal until blogger Vani Hari, of Food Babe, wrote about the negative effects of BHT. After her remarks, General Mills announced they would remove BHT from their cereals. Chemical and Engineering News reported on the change at General Mills saying that, “there is no scientific evidence that BHT is harmful in the amounts used in packaged food […] but studies of larger doses have shown mixed results.”

Some brands who use artificial preservatives include Kibbles ‘n Bits, Ol’ Roy, Pedigree, Beneful, and Hill’s Science Diet.

Zinc sulfate

Zinc sulfate contains both sulfur and zinc, which is an essential mineral for humans, dogs, and plants. Aside from dog food, zinc sulfate is also used as an herbicide for moss control.

While the name may sound scary, the benefits of zinc sulfate are anything but — two of the benefits of zinc sulfate include improving a dog’s skin and hair. Unless your dog has a skin condition, the amount of zinc sulfate in your pet’s food is usually enough for your dog to reap the benefits. If you find yourself unsure about the amount of zinc sulfate your dog is receiving, talk to a veterinarian before giving supplements to your pet.

DL-methionine

DL-methionine is derived from methionine, an essential amino acid naturally found in meat and fish. Dogs who consume meat and fish receive plenty of DL-methionine. However, because many dogs only eat dry dog food, manufacturers add the amino acid as a supplement.

Other names for DL-methionine include L-2-amino-4-(methylthio) butyric acid and L-Methionine. This can also be used to prevent and treat bladder and kidney stones in dogs. Be sure to discuss treatment options with a veterinarian to make sure DL-methionine is the best choice for your dog.

Niacin

Another name for vitamin B-3, niacin is an essential vitamin needed by both pets and humans. (Other names for vitamin B-3 are niacinamide, nicotinamide, and inositol hexaniacinate.) For more than 50 enzymes to work properly in the human body, the body must have vitamin B-3. Niacin supports healthy skin, strengthens the immune system, and helps with metabolizing carbohydrates, proteins, and fats. Some good sources of niacin are broccoli, carrots, peas, cheese, eggs, and brown rice. Interestingly, niacin is the cure for pellagra, more commonly known as Black Tongue, in dogs who have a vitamin B-3 deficiency.

DL-tryptophan

Here’s an amino acid additive with an interesting history. You may recognize tryptophan from eating lots of turkey at Thanksgiving. Supposedly, tryptophan makes humans tired, so scientists thought applying the same method to anxiety-ridden dogs would make them more calm. Studies haven’t had much success, but dog food with DL-tryptophan is still marketed to help curb anxiety.

You can find DL-tryptophan in all types of dog food. Remember, while the name sounds scary, it’s really just a more scientific way of naming an amino acid.

D-calcium pantothenate

Known as the anti-stress vitamin, vitamin B-5 (or D-calcium pantothenate) helps produce adrenal hormones and enhances stamina. All B vitamins help the body convert fat and carbohydrates to energy. B complex vitamins are also necessary for healthy skin, hair, eyes, and liver. Additionally, they help the nervous system function properly and contribute to a healthy digestive tract.

A source of vitamin B-5 often sold as a B-5 supplement. Some other sources of vitamin B-5 include beef, eggs, vegetables, wheat bran, and saltwater fish. The American Academy of Fertility Care Professionals recommended level of vitamin B-5 in dogs is 10 parts per million. If you’re concerned about your pet’s vitamin B-5 levels, talk to your vet.

Sodium selenite

Sodium selenite is an essential mineral derived from selenium. It supports immune response and plays a crucial role in limiting cellular damage.

But there is some controversy over using this ingredient in dog food. Critics believe the margin of error is too small between safe and dangerous levels. However, it’s important to note that any mineral or vitamin can become toxic when consumed in excess.

Alpha-linolenic acid

Just as you take daily vitamins every morning, so does your dog. Except while you’re swallowing a pill, your dog simply has to finish his bowl of food. Omega-3 fatty acids, sometimes called Alpha-linolenic acid, are known to be a powerhouse for helping many functions in the body. Just as omega-3 fatty acids help humans with different ailments such as heart disease, rheumatoid arthritis, and osteoporosis, omega-3 fatty acids can help dogs too.

Omega-3 fatty acids can help treat allergies, kidney disease, inflammation, and arthritis. They’re also good for prevention of these health issues. While omega-3 fatty acids can be especially helpful for older dogs, they’re beneficial for dogs of all ages.

Ethylenediamine dihydriodide

Aside from being difficult to pronounce, ethylenediamine dihydriodide is a source of iodine. Recognized by the FDA as a “generally recognized as safe” ingredient, ethylenediamine dihydriodide helps maintain proper function of the thyroid gland. Like the human body, a dog’s metabolism is also regulated by thyroid hormones. Without iodine and the proper thyroid hormones, it could inhibit a dog’s growth.

Meat meal

The Association of American Feed Control Officials defines meat meal as “rendered products from mammal tissues, exclusive of any added blood, hair, hoof, horn, hide trimmings, manure, stomach and rumen contents except in such amounts as may occur unavoidably in good processing practices.” This means manufacturers can’t add any of the aforementioned parts to the meat meal. The word “meal” refers to the fact that they grind each piece of cooked meat to the same size.

Mixed tocopherols

The ingredient “mixed tocopherols” refers to a chemical preservative made of vitamin E. Vitamin E boosts the immune system, has lots of protein, and helps give your dog a shiny coat and healthy skin.

Your dog will heal faster and have healthier circulatory system because of vitamin E. In fact, vitamin E deficiencies are associated with cell damage in the nerves, heart, liver, and skeletal muscle. And, unlike other vitamins, there’s no evidence that a high dose of vitamin E disrupts a dog’s bodily functions.

Propylene glycol

Manufacturers use propylene glycol in dog food as a thickener, stabilizer, and texturizer. This ingredient may sound familiar to pet owners who’ve heard about the lawsuit in recent years between Nestle Purina PetCare Company and their customers.

Frequent buyers of Purina’s Beneful dog food alleged that their dogs were getting sick or even dying from eating Beneful’s dry kibble. Filed in California, the lawsuit claimed toxins in the food, including propylene glycol, were to blame. Nestle Purina PetCare won the case in 2016 after a judge ruled that the plaintiffs didn’t provide enough evidence to prove Beneful was making dogs ill. Manufacturers still include propylene glycol in dog food today.

Potassium chloride

Potassium chloride is a source of the mineral potassium. A dog food industry standard, potassium chloride balances acid and alkaline levels. It’s a necessary nutrient, especially for the beating of the heart in both dogs and humans. Looking for whole foods that are rich in the mineral? Try squash, spinach, lentils, broccoli, and Brussels sprouts.