The Hidden Dangers of Preservatives in Pet Food

The Hidden Dangers of Preservatives in Pet Food

The Hidden Dangers of Preservatives in Pet Food  

Preservatives are commonly used in pet food to extend shelf life and prevent spoilage. However, there is growing concern about the potential negative health effects of these chemicals on cats and dogs. 

Types of Preservatives in Pet Food 

Preservatives in pet food can be broadly categorized into synthetic and natural preservatives. Synthetic preservatives are often used for their effectiveness and low cost. Common synthetic preservatives include: 

  1. Butylated Hydroxyanisole (BHA): A widely used antioxidant that prevents fats from becoming rancid. 
  1. Butylated Hydroxytoluene (BHT): Similar to BHA, used to extend the shelf life of pet foods. 
  1. Ethoxyquin: Originally developed as a pesticide and used as a hardening agent in the process of making synthetic rubber, it is used to prevent fat oxidation in pet foods.  

Natural preservatives, on the other hand, include ingredients such as vitamin E (mixed tocopherols), vitamin C (ascorbic acid), and various herbal extracts, such as rosemary. 

Potential Health Impacts 

Synthetic Preservatives 

  1. BHA and BHT: 
  • Carcinogenic Potential: Both BHA and BHT have been classified as potential human carcinogens by the International Agency for Research on Cancer (IARC) due to evidence of causing tumors in animal studies. 
  • Endocrine Disruption: These chemicals can mimic hormones and interfere with the endocrine system, potentially leading to developmental and reproductive issues. 
  • Allergic Reactions: In some pets, these preservatives can trigger allergic reactions, leading to skin irritations and gastrointestinal problems. 
  1. Ethoxyquin: 
  • Liver and Kidney Damage: Ethoxyquin has been linked to liver and kidney damage in animals. 
  • Immune System Suppression: Studies suggest that ethoxyquin may suppress the immune system, making pets more susceptible to diseases. 
  • Cancer Risk: There are concerns that long-term exposure to ethoxyquin may increase the risk of certain cancers in pets . 
  • Ethoxyquin has been under investigation by the FDA as a possible cause for certain liver and blood problems. 
  • In addition, the preservative is not permitted for use in Australian dog foods nor is it approved within in the European Union.  
  • Yet to this day, ethoxyquin is still commonly found in many popular brands of dog food. 

Natural Preservatives 

While natural preservatives are generally considered safer, they are not without their own potential issues. For example, high levels of vitamin E can cause hypervitaminosis E, which can lead to health problems such as impaired blood clotting in pets. However, the risks associated with natural preservatives are significantly lower compared to their synthetic counterparts. 

Benefits of Preservative-Free Pet Food 

  1. Reduced Risk of Chronic Diseases: Eliminating synthetic preservatives can lower the risk of chronic diseases such as cancer and organ damage. 
  1. Improved Digestion and Allergy Relief: Many pets experience better digestion and fewer allergic reactions when their diet is free of artificial additives. 
  1. Enhanced Nutritional Quality: Preservative-free pet foods often contain fresher, higher-quality ingredients, providing better overall nutrition for pets. 


While preservatives play a role in extending the shelf life of pet food, their potential health risks cannot be ignored. Synthetic preservatives such as BHA, BHT, and ethoxyquin have been linked to serious health issues, including cancer, organ damage, and immune system suppression. Opting for preservative-free or naturally preserved pet food can significantly reduce these risks and promote better health and well-being for cats and dogs.  

All Nibbs Club food and treats are guaranteed preservative-free. In fact, we are supporting several families whose senior pets have been diagnosed with cancer or chronic diseases and whose parents now need to pay particular attention to the ingredients in their pet’s diet. Giving your pet a preservative-free diet can lower their risk for cancer and other chronic illnesses, especially in their old age. Check out our range of healthy options here and read about our Nibbs Club stories here 

Back to blog