Q There used to be a lot of talk about the dangers of BHA, BHT and ethoxyquin used as preservatives in certain pet foods. Have they been replaced by different ingredients, or are there simply fewer concerns about them now?
Elizabeth M. Randall
A Dear Elizabeth: There is currently less discussion about these synthetic preservatives, mainly because they have largely been replaced in most dry commercial pet foods. Interestingly, they were removed because of consumer demand for naturally preserved products — not because there was actual evidence that they are harmful.
Most pet foods are now preserved with mixed tocopherols (vitamin E derivatives), citric acid and/or rosemary extract. Curiously, there is less data on safety and efficacy of these natural products than there is for the synthetic preservatives, yet they appeal to consumers because they are “natural.”
There is some evidence that natural preservatives may not be as effective as synthetic preservatives, so this change does place more responsibility on pet food manufacturers to insure that their products are adequately preserved to provide appropriate nutrition throughout the shelf life of the product. Additionally, pet owners are encouraged to check the expiration date on food bags before purchasing.
If pet owners want to avoid preservatives entirely, they can feed their pets a diet of canned food, which utilizes the canning process to keep food from going bad.
Cailin Heinze, MS, VMD, DACVN
Veterinary Clinical Nutritionist
Cummings School of Veterinary
Medicine at Tufts University