Diamond Naturals Grain Free Dog Food earns the Advisor’s mid-tier rating of 3.5 stars.
The Diamond Naturals Grain Free product line includes three dry dog foods, each claimed to meet AAFCO nutrient profiles for all life stages.
The following is a list of recipes available at the time of this review.
- Diamond Naturals Grain Free Beef and Sweet Potato
- Diamond Naturals Grain Free Chicken and Sweet Potato
- Diamond Naturals Grain Free Whitefish and Sweet Potato
Diamond Naturals Grain Free Beef and Sweet Potato was selected to represent the other products in the line for this review.
Diamond Naturals Grain Free Beef and Sweet Potato
Dry Dog Food
Estimated Dry Matter Nutrient Content
Ingredients: Beef, lamb meal, sweet potatoes, peas, potatoes, garbanzo beans, canola oil (preserved with mixed tocopherols), potato protein, tomato pomace, flaxseed, potato fiber, natural flavor, fish meal, salt, choline chloride, dried chicory root, Yucca schidigera extract, tomatoes, blueberries, raspberries, dried Enterococcus faecium fermentation product, dried Lactobacillus acidophilus fermentation product, dried Lactobacillus casei fermentation product, dried Lactobacillus plantarum fermentation product, dried Trichoderma longibrachiatum fermentation extract, vitamin E supplement, iron proteinate, zinc proteinate, copper proteinate, ferrous sulfate, zinc sulfate, copper sulfate, potassium iodide, thiamine mononitrate (vitamin B1), manganese proteinate, manganous oxide, ascorbic acid, vitamin A supplement, biotin, niacin, calcium pantothenate, manganese sulfate, sodium selenite, pyridoxine hydrochloride (vitamin B6), vitamin B12 supplement, riboflavin (vitamin B2), vitamin D supplement, folic acid
Fiber (estimated dry matter content) = 5.6%
Red items when present indicate controversial ingredients
|Estimated Nutrient Content|
|Dry Matter Basis||27%||16%||50%|
|Calorie Weighted Basis||23%||33%||44%|
The first ingredient in this dog food is beef. Although it’s a quality item, raw beef contains about 80% water. After cooking, most of that moisture is lost, reducing the meat content to just a fraction of its original weight.
After processing, this item would probably account for a smaller part of the total content of the finished product.
The second ingredient is lamb meal. Lamb meal is considered a meat concentrate and contains nearly 300% more protein than fresh lamb.
The third ingredient is sweet potato. Sweet potatoes are a gluten-free source of complex carbohydrates in a dog food. They are naturally rich in dietary fiber and beta carotene.
The fourth ingredient is peas. Peas are a quality source of carbohydrates. And like all legumes, they’re rich in natural fiber.
However, peas contain about 25% protein, a factor that must be considered when judging the meat content of this dog food.
The fifth ingredient is potato. Potatoes can be considered a gluten-free source of digestible carbohydrates. Yet with the exception of perhaps their caloric content, potatoes are of only modest nutritional value to a dog.
The sixth ingredient is garbanzo beans, also known as chickpeas. Like peas, bean and lentils, the chickpea is a nutritious member of the fiber-rich legume (pulse) family of vegetables.
Garbanzos contain about 22% protein, something which must be considered when evaluating the total protein reported in this food.
The seventh ingredient is canola oil. Unfortunately, canola can be a controversial item. That’s because some worry that canola oil is made from rapeseed, a genetically modified (GMO) raw material.
Yet others cite the fact canola oil can be a significant source of essential omega-3 fatty acids.
In any case, plant-based oils like canola are less biologically available to a dog than fish oil as a source of quality omega-3 fats.
The eighth ingredient is potato protein, the dry residue remaining after removing the starchy part of a potato.
Even though it contains over 80% protein, this ingredient would be expected to have a lower biological value than meat.
And less costly plant-based products like this can notably boost the total protein reported on the label — a factor that must be considered when judging the actual meat content of this dog food.
The ninth ingredient is tomato pomace. Tomato pomace is a controversial ingredient, a by-product remaining after processing tomatoes into juice, soup and ketchup.
Many praise tomato pomace for its high fiber and nutrient content, while others scorn it as an inexpensive pet food filler.
Just the same, there’s probably not enough tomato pomace here to make much of a difference.
From here, the list goes on to include a number of other items.
But to be realistic, ingredients located this far down the list (other than nutritional supplements) are not likely to affect the overall rating of this product.
With three notable exceptions…
First, flaxseed is one of the best plant sources of healthy omega-3 fatty acids. Provided they’ve first been ground into a meal, flax seeds are also rich in soluble fiber.
However, flaxseed contains about 19% protein, a factor that must be considered when judging the actual meat content of this dog food.
Next, chicory root is rich in inulin, a starch-like compound made up of repeating units of carbohydrates and found in certain roots and tubers.
Not only is inulin a natural source of soluble dietary fiber, it’s also a prebiotic used to promote the growth of healthy bacteria in a dog’s digestive tract.
And lastly, this food also contains chelated minerals, minerals that have been chemically attached to protein. This makes them easier to absorb. Chelated minerals are usually found in better dog foods.
Diamond Naturals Grain Free Dog Food
The Bottom Line
Judging by its ingredients alone, Diamond Naturals Grain Free looks like an above-average dry dog food.
But ingredient quality by itself cannot tell the whole story. We still need to estimate the product’s meat content before determining a final rating.
As a group, the brand features an average protein content of 27% and a mean fat level of 16%. Together, these figures suggest a carbohydrate content of 50% for the overall product line.
And a fat-to-protein ratio of about 58%.
Near-average protein. Near-average fat. And above-average carbs when compared to a typical dry dog food.
When you consider the protein-boosting effects of the peas, garbanzo beans, potato protein and flaxseed, this looks like the profile of a kibble containing a modest amount of meat.
Diamond Naturals Grain Free is a plant-based dry dog food using a modest amount of lamb, chicken or fish meals as its main sources of animal protein, thus earning the brand 3.5 stars.
Please note certain recipes are sometimes given a higher or lower rating based upon our estimate of their total meat content.
Rice ingredients can sometimes contain arsenic. Until the US FDA establishes safe upper levels for arsenic content, pet owners may wish to limit the total amount of rice fed in a dog's daily diet.
A Final Word
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Notes and Updates
04/26/2013 Original review
04/10/2014 Last Update