What Is Sodium Selenite?
Sodium Selenite is an organic compound that is a mix of Sodium and Selenium. It comes in a colorless powdered form that can easily be dissolved in water.
Sodium Selenite has limited use but is mainly used in the production of glass, as it can help produce colorless glass.
However, Sodium Selenite’s secondary use is as a dietary supplement, and it is commonly found in dietary supplements such as the Vitamins and Mineral supplements you would find in your local grocery store.
However, the FDA also approved Sodium Selenite for use as a supplement to animal feed such as dog food.
This approval was given several decades ago before selenium compounds were well understood, and Sodium Selenite and Sodium Selenate happened to be the forms of selenium that were easily available.
Why Is Sodium Selenite In Dog Food?
As we alluded to above, Sodium Selenite is present in dog food for the same reason that several other minerals are included to provide trace amounts of Selenium to dogs.
Selenium is usually present in water and some foods, such as nuts, fish, red meat, poultry, and grain ingredients.
However, for certain dog food formulas that have minimal of these ingredients, they may need to boost the natural levels of Selenium present.
Selenium is an important mineral for dogs and humans, and some associate it with benefits such as high levels of antioxidants, a reduction in the risk of certain cancers, and various others, such as arthritis.
However, many of the benefits of Selenium are far from conclusive, with many suggesting that boosting the level of Selenium may have minimal effects.
Is Sodium Selenite Bad For Dogs?
At the correct levels, Selenium is not toxic to dogs and is actually an important mineral for several reasons.
However, some studies in rats suggested that Sodium Selenite was 2.94 times more toxic than an alternative form of Selenium called Selenium Yeast.
Unfortunately, there have not been identical studies done on dogs to see if that is also the case for them, so it’s difficult to know if we can make assumptions based on this.
Regardless of the form of Selenium, taking it in high doses is most definitely toxic to dogs and is something that should not be done.
Thankfully, the levels of Selenium in most dog food brands are barely above the minimum required, so it will not cause any kind of toxicity.
For example, in Purina Pro Plan’s Adult Complete Essentials Shredded Blend Salmon & Rice formula, which includes a small amount of Sodium Selenite, the overall levels of Selenium are 0.35mg/kg, which are far below the maximum recommended intake of 2mg/kg.
Dog Food Brands That Use Sodium Selenite
Most dog owners will be completely unaware that their dog’s favorite food contains minerals like Sodium Selenite.
Many of the larger dog food brands that are well-known use trace amounts of this mineral in their recipes.
In fact, while performing research on dog food ingredients, we found that from the 100 bestselling dry dog food recipes on Chewy.com, 99 of them contained Sodium Selenite which was a surprise, even to us.
Some examples of dog food brands that use Sodium Selenite include Purina Pro Plan, Hill’s Science Diet, Taste of the Wild, Blue Buffalo, Iams, Royal Canin, and Rachael Ray Nutrish.
You can see a simple example of the use of Sodium Selenite in the ingredient list of Iam’s Adult Large Breed Real Chicken recipe.
Here Sodium Selenite is joined by several other common minerals in dog food recipes such as Zinc Oxide, Manganese Sulfate, and Potassium Iodide.
If for some reason, you were not happy about the inclusion of Sodium Selenite in your dog’s food, we would recommend studying the ingredient list of any potential recipes to see if it is present.
You may also want to contact the manufacturer of the recipes to understand the typical levels of Selenium in the recipe.
If you need help selecting a high-quality dog food recipe, take a look at our Dog Food Guide or visit our Pet Food Brand Review Index for the full list of brands we’ve analyzed to date.
I called Blue Buffalo and Merrick about the amount of sodium selenite in their dog foods. Both of them told me that was proprietary information and cannot give me that information. interesting. That tells me either they do not know and maybe it is a total lie that it is not even in there. So if I have a dog with low selenium levels and want to supplement her diet I have no clue what she is already getting through her food. These companies are not very transparent.