Kirkland Signature Dry DOG FOOD Review

With a score of 3.4/10, Kirkland Signature Dry is considered a high risk dog food. There are 6 recipes that average 26% protein and 40% carbohydrate as calculated.

The carbohydrate level is excessively high which contributes toward the lower score. Within the top 10 ingredients you’ll find as many as 6 or 7 grains and starches like rice peas, barley, millet, legumes, sweet potatoes, oatmeal, potatoes. Dogs have no nutritional requirement for carbohydrates but starch is required for extrusion in dry foods like these. Excessive carbohydrate are an indicator of low quality foods as they are used to keep costs down. Large amounts of starch can increase insulin levels, cause obesity and negatively impact gut balance.

This line loses significant ingredient quality points for excessive added vitamins and minerals. One recipe has added amino acids. This usually reflects poor quality or overly processed ingredients. Ideally, these nutrients should come from whole food sources. Vitamin and mineral excesses, especially vitamin D and copper, can also result from vitamin premixes. 

It’s also worth noting that the line contains sodium selenite as a source of selenium. Dogs need selenium, and it’s usually added in very small amounts. However some research suggests that sodium selenite may be associated with potential toxicity, so selenium yeast is the preferred form of this mineral.  

The line also loses quality points for using plant proteins. Plant proteins are a low cost substitute for quality animal protein. Animal sources of protein are preferred because they contain a wider array of amino acids and are more digestible. 

These recipes include fish meal which is an unspecified animal ingredient. You want to see beef, salmon or chicken, not animal, fish or poultry. Unnamed protein sources are of much lower quality which are typically from rendered waste. 

The Healthy Weight recipe contains cellulose, presumably to create satiety and firm stools, but this is a low quality insoluble fiber which is a cheap substitute for soluble fiber obtained in food along with other nutrients. 

It doesn’t improve the score, but it’s good to see that 5 of these recipes include a guaranteed amount of probiotics.

The ingredient safety scores for this line are low, with many concerns. Like all kibbles, Kirkland Signature Dry is ultra-processed. The individual ingredients in dry dog foods are heated several times during processing, which can cause a significant loss of enzymes, vitamins, amino acids and phytonutrients. Processed foods are also linked to higher mortality rates in many species. 

These recipes use ingredients with known high pesticide or herbicide residues, like oatmeal, peas and barley, often in the top 5 ingredients. Pesticides, herbicides and fertilizers pose a significant health risk to plants, animals and soils. Foods with the largest reported amount of residue are penalized, including crops that are known to be spray-dried with glyphosate. Potatoes are a known GMO used in these recipes. There are limited safety studies on genetically modified and Roundup Ready crops although they are lacking in nutrients compared to non-GMO foods. GMO crops also strip nutrients from soils, require increased pesticide risk and may be involved in bee die-off.

Another ingredient safety concern costing points is the use of rice. Arsenic contamination is a significant concern since rice naturally absorbs arsenic and the water it’s grown in can be contaminated with arsenic. Arsenic is linked to chronic health issues. Finally, points are lost as natural flavor is used in each recipe to make processed food more palatable. Natural flavor is often either MSG or animal digest, both low quality ingredients with limited safety studies.

It doesn’t cost points, but several recipes use ingredient splitting. This is when ingredients are split into sub-categories (like brown rice and white rice) to move certain ingredients higher or lower on the ingredient list. This is often used to disguise the amount of lower quality ingredients in the food, such as corn, rice, potatoes or peas, and moves desirable ingredients, like proteins, higher.

All of these recipes contain glam ingredients. These are expensive or desirable ingredients like blueberries, kale and apples that are often added to appeal to consumers but may be in minute amounts when they’re below the salt in the ingredient list. Salt is an ingredient added in small amounts so anything listed after salt adds little or no nutritional value.  

These recipes include fish meal but they don’t specify whether the fish sources are farmed or wild caught. Farmed fish is less nutritious than wild caught fish and doesn’t contain the same healthy fatty acid balance. 

Kirkland doesn’t provide the omega-6 to omega-3 ratio. They’re not the only brand not providing this, but it’s a concern because diets rich in omega-6 fats can cause chronic inflammation and disease, and AAFCO allows a highly inflammatory level of 30:1.