Table of Contents

Controversial and Dangerous Ingredients and Additives in Hamster Food Mixes

Over the past few decades, the use of food additives in pet food has risen. Understandably, this increase has raised concerns about the safety of these additives. Many pet owners worry that these additives may have adverse effects on their pets, and we have conducted research to investigate the evidence supporting these concerns.

Added Sugars and Sweeteners

Manufacturers use artificial sweeteners to make pet food and treats taste better. Sugar is also known to be addictive, and some forms of sugar can be harmful to the cheek pockets as it can be very sticky.

Some forms of sugar are often used as a binder to hold certain pellets in food together. One example of this is cane molasses, a dark liquid made from sugar cane. Oxbow uses it as a binder in their own pellets.

Sugar may not be inherently bad on its own, however, any food mix rich in sugar may be an indicator that it is of low quality and should be avoided.

Xylitol (E976) is a sugar alcohol that is used as an artificial sweetener and flavor enhancer in many foods like peanut butter. In the pet food community, Xylitol is known for being dangerous for dogs to ingest.

A study done by Truhaut et al in 1977 found no signs of liver damage or hepatoxicity in rats that were administered xylitol in various dose levels (1.25, 2.5, 5, and 10 g/kg) for up to 2 weeks. However, previous research has suggested potential liver dysfunction with shorter exposure.

A study done in 1982 showed that rats and mice were capable of adapting to a diet with a 20% xylitol content. However, a significant amount (22g/kg) of xylitol is required to be lethal, but it is not a dosage that would typically be encountered in food for rodents.

Examples of Added Sugar and Sweeteners

  1. Corn Syrup
  2. Corn Sugar
  3. Dextrose
  4. Fructose
  5. Sucrose
  6. Fruit Juices
  7. Dried Fruit
  8. Molasses
  9. Rice Syrup
  10. Honey
  11. Xylitol

Artificial Dyes

Artificial coloring is usually added to food to make it more visually pleasing. There are no real nutritional benefits to adding artificial dyes, and the ones that aren’t considered dangerous also do not improve the safety of the food either.

Blue 2, Red 40, Yellow 5, and Yellow 6 have all been documented to contribute to allergic-type hypersensitivity reactions, behavior problems, and cancer in humans. 4-MIE and Red 3 are known animal carcinogens, and there is evidence that other dyes are also carcinogenic.

Red 40, Yellow 5, and Yellow 6 have also been found to be contaminated with benzidine and other carcinogens. Yellow 5 has also been shown to be positive for genotoxicity. There were also toxicity tests on Citrus Red 2 and Orange B that suggest safety concerns, with the latter not being used in recent years.

Artificial coloring is mainly used for aesthetic purposes for humans and doesn’t increase the nutritional value of food for hamsters, so it is best to avoid them.

Risky Dyes

  1. Blue 2
  2. Green 3
  3. Red 3
  4. Red 40
  5. Yellow 5
  6. Yellow 6
  7. 4-Methylimidazole (4-MIE)
  8. Citrus Red 2
  9. Orange B

Natural Ingredients

Onions have been shown to have some beneficial properties. A study by Guan et al in 2010 suggests that dietary onion powder can lead to lower cholesterol levels. It’s safe when cooked into other foods, but shouldn’t be given to hamsters raw or on its own.

Garlic can be beneficial for hamsters. Garlic and onion both have positive effects on various health parameters, but garlic may be better at lowering plasma lipids and suppressing antioxidative enzyme activities in hamsters.

Garlic is also associated with beneficial effects on preventing peroxides, platelet aggregation, and thrombosis. A study done in 2005 showed that the combination of tomatoes and garlic appears to protect hamsters against cancer development by influencing the enzymes that are responsible for metabolizing harmful compounds.

A study done in 2022 on mice suggests that the oral administration of garlic and tomato (either individually or in combination) can protect against the harmful effects of the carcinogen DMBA.

However, garlic should not be eaten raw or on its own.

Leeks can also have positive benefits in hamsters. Persian leeks had a positive impact on hamsters who were fed a high-fat high-cholesterol diet by improving their liver function and reducing inflammation. However, just like garlic and onions, leeks shouldn’t be eaten raw or on its own.


Butylated Hydroxyanisole (BHA) and Butylated Hydroxytoluene (BHT)
Butylated Hydroxyanisole (BHA) and Butylated Hydroxytoluene (BHT) are two antioxidants that are added to oils (fats) as preservatives.

BHA is a known reproductive toxicant. BHT can cause kidney and liver damage in rats. Both BHA and BHT have been shown to interfere with hormonal balances in rats.

They are known carcinogens. A study conducted by Ito et al in 1985 suggests that BHA is carcinogenic in Syrian Golden hamsters. In their studies, both groups of hamsters fed BHA diets developed tumors in their forestomach. Their findings indicated that a 2-year carcinogenicity test with BHA administered in the diet would likely yield positive results. It is also noted that hamsters appear to be more susceptible to the carcinogenic effects of BHA in the forestomach compared to rats.

Ethoxyquin is an inexpensive and synthetic chemical preservative and antioxidant used in pet foods and animal feed. It is also known as santoquin, santoflex, quinol. Ethoxyquin often enters pet food under “fish meal” and may not actually appear on any label. It is considered rare to find ethoxyquin blatantly labeled on pet food.

Dr. Karen Becker, a renowned veterinarian says, “Most fish meal in commercial pet foods contain the potentially deadly preservative ethoxyquin, but chances are you won’t find it on the label.”

In skin irritation tests done on rabbits and rats (following OECD Guideline 404), the tests found mild and temporary irritation when these animals were exposed to ethoxyquin. There were also eye irritation tests conducted on rabbits. One test found persistent and conjunctival redness which led to ethoxyquin being classified as an eye irritant. There have been reports of severe allergic contact dermatitis in workers handling animal feed containing ethoxyquin, even at low concentrations.

A metabolite of ethoxyquin has been identified as possibly having harmful effects on genetic material. An impurity associated with ethoxyquin could also cause mutations in DNA. In dogs, there have been reported cases of allergic reactions and other health problems that affect the skin, liver, kidney, thyroid, and even the reproductive system. However, these associations haven’t been definitely confirmed.

Ethoxyquin is carcinogenic in rats. It is harmful to humans if swallowed directly. In the United States, it is illegal to use ethoxyquin in any food for human consumption, with the exception of some spices such as paprika and and to prevent browning in certain fruit. In the European Union, ethoxyquin has been completely banned.

In 1997, the Center for Veterinary Medicine have asked the American pet food industry to reduce the maximum allowable level in dog dood. According to Toxin Free USA, if you’re concerned about Ethoxyquin in your pet food, fish-based pet foods are the highest risk.

Propylene Glycol (PG)
Propylene Glycol is a synthetic preservative. It is a clear, colorless, and near-odorless liquid. It is used to absorb water and maintain moisture levels in food. It is said to be slightly sweet tasting.

The FDA lists Propylene Glycol as “generally recognized as safe” except for cats. This is because cats are particularly sensitive to PG, and the use of PG in cat food is no longer allowed. In 1994, tests indicated that PG is not mutagenic or carcinogenic in rats and Chinese hamsters. Dr. Greg Aldrich asserts that the small amount of PG in pet food is nothing to be concerned with and that it plays a part in meeting pet food quality standards.


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