25 Human Foods Cats Should Never Eat

Some foods can be poisonous or even deadly for cats. Anyone who suspects their pet has ingested any harmful foods should note the amount consumed and contact their veterinarian or the ASPCA (American Society for the Prevention of Cruelty to Animals) Animal Poison Control Center at 1-888-426-4435.

Here are some common human foods that cats should not eat.

Coffee and tea

Both drinks, as well as coffee grounds and even used tea bags, are unsafe for cats due to their caffeine content.

Within one to two hours of exposure to caffeine, cats and other pets can experience "mild to severe hyperactivity, restlessness, vomiting, tachycardia (elevated heart rate), hypertension (elevated blood pressure), abnormal heart rhythms, tremors, hyperthermia (elevated body temperature) seizures, and collapse," according to the Pet Poison Helpline, a national licensed animal poison center.

Energy drinks

Many energy drinks also contain caffeine, which contains methylxanthines (toxic substances found in cacao seeds).

"When ingested by pets, methylxanthines can cause vomiting and diarrhea, panting, excessive thirst and urination, hyperactivity, abnormal heart rhythm, tremors, seizures and even death," the ASPCA explains.

Chocolate

Chocolate also contains methylxanthines. "Note that darker chocolate is more dangerous than milk chocolate. White chocolate has the lowest level of methylxanthines, while baking chocolate contains the highest," the ASPCA says.

Meat

Raw meat can be harmful to cats because it may contain bacteria such as Salmonella and E. coli.

Eggs

The ASPCA says: "Raw eggs contain an enzyme called avidin that decreases the absorption of biotin (a B vitamin), which can lead to skin and coat problems," for cats and other pets.

Fish

Raw fish can also be harmful to cats because it contains an enzyme that destroys thiamine, an essential B vitamin for cats. Low levels of thiamine could cause serious neurological issues, which could result in convulsions and coma, according to an article reviewed by veterinarian Amy Flowers on WebMD.

Canned tuna

While a little bit of tuna may not be harmful, cats can get addicted to it and too much may lead to mercury poisoning, WebMD reports.

Onions

Onions may be dangerous for cats because they can cause gastrointestinal irritation and lead to red blood cell damage and anemia, the ASPCA warns.

Garlic

Garlic is considered to be about five times as potent as onions and is toxic for cats. The Pet Poison Helpline explains: "Toxic doses of garlic can cause damage to the red blood cells (making them more likely to rupture) leading to anemia."

Cats who ingest garlic may experience nausea, drooling, abdominal pain, vomiting and diarrhea. "Signs of garlic poisoning can be delayed and not apparent for several days," the Pet Poison Helpline says.

Fat

Cats licking fat trimmings off table scraps or other foods lying around could be dangerous. Fat, whether cooked and uncooked, can lead to gastrointestinal upset in cats, including vomiting and diarrhea, according to WebMD.

Nuts

Nuts, such as almonds, pecans, and walnuts, have high amounts of oils and fats, which can cause vomiting and diarrhea as well as possibly pancreatitis in cats, according to the ASPCA.

Bones

Cats nibbling on bones leftover from human meals can also be hazardous. They could either choke on the bones or "sustain a grave injury should the bone splinter and become lodged in or puncture your pet's digestive tract," the ASPCA warns.

Liver

While small amounts of liver are harmless, too much consumption can be harmful to cats. Eating too much liver can lead to vitamin A toxicity, which impacts cats' bone health and could even cause death. Symptoms can include deformed bones, bone growths on the elbows and spine as well as osteoporosis, according to WebMD.

Grapes and raisins

It has yet to be determined why grapes and raisins can be toxic for cats, as well as dogs.

The Pet Poison Helpline said: "To date, dogs are the only species positively identified as being sensitive to these foods, but there are a few anecdotal cases of cats developing renal problems as a result of grape/raisin ingestion. This could also be, in part, to cats merely having no interest in eating these products.

"To be precautious, depending on the number ingested it is typically recommended to treat feline ingestions in a similar manner to canines," it adds.

Peaches

The stems, leaves and seeds of peaches contain cyanide, which is poisonous to cats and other pets. They are "particularly toxic in the process of wilting," the ASPCA says. Symptoms of poisoning can include dilated pupils, difficulty breathing, panting and shock.

Tomatoes

While ripe tomatoes are non-toxic, tomato plants are poisonous. Symptoms include "hypersalivation, inappetence, severe gastrointestinal upset, depression, weakness, dilated pupils, slow heart rate," the ASPCA says.

Yeast

Yeast dough can rise and lead to gas build-up in your cat's digestive system. This can be painful, causing the stomach to bloat and "potentially twist, becoming a life-threatening emergency," the ASPCA warns.

Milk

Milk and other dairy products can be harmful because cats and other pets lack significant amounts of lactase, the enzyme that breaks down lactose in dairy products. Having milk or other dairy-based foods can cause diarrhea or other digestive issues.

Alcohol

Alcohol and any foods containing alcohol can cause vomiting, diarrhea, decreased coordination, central nervous system depression, difficulty breathing, tremors, abnormal blood acidity, coma and even death in cats and other pets.

"Under no circumstances should your pet be given any alcohol. If you suspect that your pet has ingested alcohol, contact your veterinarian or the ASPCA Animal Poison Control Center immediately," the ASPCA warns.

Citrus

Citrus plants, including the stems, leaves, peels, fruit and seeds, contain different amounts of citric acid, which "cause irritation and possibly even central nervous system depression if ingested in significant amounts," the ASPCA warns.

Coconut

Fresh coconuts and coconut milk contain oils that can cause upset stomach, loose stools or diarrhea for cats, but small amounts are not likely to be harmful. "Coconut water is high in potassium and should not be given to your pet," the ASPCA says.

Candy

Candy products containing xylitol, an artificial sweetener, can be dangerous for cats. Ingestion of xylitol can cause a spike in insulin levels, which can lead to liver failure. "The increase in insulin leads to hypoglycemia (lowered sugar levels). Initial signs of toxicosis include vomiting, lethargy and loss of coordination. Signs can progress to seizures. Elevated liver enzymes and liver failure can be seen within a few days," the ASPCA says.

Gum

In addition to containing xylitol, chewing gum can potentially cause blockages in the throat if ingested by cats and other pets.

Salty snacks

Snacks such as potato chips, pretzels, popcorn and other foods with high salt content, should be avoided because too much salt consumption can "produce excessive thirst and urination, or even sodium ion poisoning in pets," the ASPCA notes.

Human medicine

Medication used by humans should not be given to cats unless advised by a veterinarian, the U.S. Food and Drug Administration warns.

"For example, nonsteroidal anti-inflammatory drugs for people, such as aspirin, ibuprofen, and naproxen, may not be right for your pet and may even be harmful," the FDA says.

Acetaminophen, the ingredient found in Tylenol, an over-the-counter pain killer, is also harmful to cats. The Pet Poison Helpline advises: "Cats have a decreased ability to metabolize acetaminophen in their liver, making them much more susceptible to poisoning than most other species. Just one dose of this medication when given to your cat could possibly cause concern for toxicity!"

Grapes California market
Grapes pictured at a market in Monterey Park, California on July 25, 2014. Frederic J. Brown/AFP via Getty Images