In this comparison article for Purina Cat Chow vs Hill's Science Diet, we'll highlight the key differences between these two pet food brands. To properly compare Purina Cat Chow and Hill's Science Diet, we'll use up-to-date nutritional and price information.
There are many factors to consider when choosing the best pet food brand for your pet. Factors such as ingredient quality, guaranteed analysis, product safety, brand history, and cost are among the most important factors to consider.
Throughout this Hill's Science Diet vs Purina Cat Chow comparison, we've utilized average data to make general comparisons. If you'd like to see individual product reviews, visit our Purina Cat Chow Review Page or Hill's Science Diet Review Page.
Guaranteed Analysis: Hill's Science Diet vs. Purina Cat Chow
According to AAFCO, all pet food labels must provide a guaranteed analysis of nutrient content. The analysis must provide guaranteed minimum percentages of crude protein and crude fat, and maximum percentages of crude fiber and moisture.
All percentages used in this comparison are averages reported on a dry matter basis.
Protein is an extremely important part of your cat's diet. Without sufficient protein, cats can develop a wide-range of serious health problems.
According to our data, Purina Cat Chow guarantees 3.36% more protein than Hill's Science Diet. Although this difference is relatively small, it's still a notable difference.
Crude Fat Comparison For Cat Food
There are many ways in which dietary fat contributes to the overall health of our feline friends. Here is a short list of benefits provided by fats (not exhaustive):
Fats help with the digestion and absorption of fat-soluble vitamins
Reduce inflammation associated with arthritis
Slow the growth of yeast infections
Prevent or reduce the likelihood of certain heart problems.
Aid in the development of the retina and visual cortex.
Our analysis shows that Hill's Science Diet guarantees 5.58% more fat than Purina Cat Chow dry cat food recipes.
Purina Cat Chow and Hill's Science Diet both provide roughly the same amount of crude fiber.
Purina Cat Chow Pet Food Ingredients vs. Hill's Science Diet Pet Food Ingredients
Purina Cat Chow and Hill's Science Diet both use the following controversial ingredients in many of their products:
Pea Protein
Pea Protein
Pea protein is produced by removing the starchy parts of peas. Pea protein is considered controversial because it provides a substantial plant based protein boost. This boost is undesirable because plant based protein is typically lower in biological value when compared to meat based proteins.
Brewers Rice
Brewers Rice
Brewer's rice is the small fragments of rice kernel that are separated from the larger kernels of milled rice. The fragments do not contain the same nutrition profile of the whole kernel and therefore brewer's rice is a lower quality grain. Brewer's rice is typically regarded as an inexpensive and low quality filler.
Corn Gluten Meal
Corn Gluten Meal
Corn gluten meal is a by-product from the production of various corn products (corn starch, corn syrup, etc). It's very high in protein (nearly 60% protein) and therefore can significant boost the protein content of the product. Because plant based proteins such as corn gluten meal are inferior to meat based proteins (lack many essential amino acids), they are not suitable substitutes.
Whole Grain Corn
Whole Grain Corn
Whole grain corn is the entire corn kernel (the germ, bran, and endosperm). Corn is a cereal grain which provides a modest amount of vitamins, minerals, and plant based protein. It also happens to be one of the most controversial ingredients in pet food.
Proponents of corn claim that corn is highly digestible and an excellent source of protein, energy, vitamins, minerals, and essential fatty acids.
Opponents however believe that positive claims in regards to corn are either half-truths or completely false, we'll discuss a few of the opposing arguments.
In regards to digestibility, the claims of "highly digestible" are only true if corn is processed into a meal or flour and subsequently cooked. In regards to the protein contribution, we must note that corn is a plant based protein which does not contain all of the necessary amino acids required by pets to sustain life. Therefore substituting corn for meat is an unsuitable substitution and actually degrades the overall protein quality of the product.
Finally, we'll discuss the claims about vitamins and minerals in corn. Although corn does provide many vitamins and minerals, it not necessarily an exceptional ingredient in this regards. There are many other ingredients which are more complete and biologically appropriate. Therefore the usage of corn as the primary ingredient in pet food should certainly warrant further questioning.
Whole Grain Wheat
Whole Grain Wheat
Whole grain wheat contains the entire grain of wheat (the germ, bran, and endosperm). Wheat is the second most-produced cereal grain in the world (corn is the first). Although wheat is a controversial ingredient, it is not necessarily undesirable because it provides dietary fiber and many other nutrients. However, wheat contains a notable amount of plant based protein, which is inferior to meat based protein and therefore an undesirable substitution.
Wheat is also one of the most common ingredients to cause food allergies or intolerance. However, grains such as wheat are typically low offenders in comparison to certain protein sources (such as beef).
Powdered Cellulose
Powdered Cellulose
Powdered cellulose is produced from minuscule pieces of wood pulp and plant fibers. Other than its fiber content, powdered cellulose lacks any nutritional contribution.
Here are some of the controversial ingredients used only by Purina Cat Chow.
Corn Meal
Corn Meal
Corn meal is another name for ground corn. Corn is a cereal grain which provides a modest amount of vitamins, minerals, and plant based protein. It also happens to be one of the most controversial ingredients in pet food.
Proponents of corn claim that corn is highly digestible and an excellent source of protein, energy, vitamins, minerals, and essential fatty acids.
Opponents however believe that positive claims in regards to corn are either half-truths or completely false, we'll discuss a few of the opposing arguments.
In regards to digestibility, the claims of "highly digestible" are only true if corn is processed into a meal or flour and subsequently cooked. In regards to the protein contribution, we must note that corn is a plant based protein which does not contain all of the necessary amino acids required by pets to sustain life. Therefore substituting corn for meat is an unsuitable substitution and actually degrades the overall protein quality of the product.
Finally, we'll discuss the claims about vitamins and minerals in corn. Although corn does provide many vitamins and minerals, it not necessarily an exceptional ingredient in this regards. There are many other ingredients which are more complete and biologically appropriate. Therefore the usage of corn as the primary ingredient in pet food should certainly warrant further questioning.
Canola Meal
Canola Meal
Canola meal is a high protein by-product of canola oil production. This ingredient is marked controversial because it may be derived from genetically modified rapeseed, which is associated with multiple adverse health affects.
Ground Wheat
Ground Wheat
Ground wheat is regarded as an inexpensive and low-quality filler in pet food. However, wheat does provide plant-based protein and makes pet food more affordable for consumers. It's important to note that plant based protein does not provide the same amino acid profile as meat based protein.
Soybean Flour
Soybean Flour
Soybean flour contains more than 50% protein. Therefore, soybean can significantly boost the protein content of the product. The inclusion of non-meat protein typically degrades the overall quality of protein in the recipe. This degradation is due to the inferior amino acid profile of plant based proteins.
Soybean Hulls
Soybean Hulls
Soybean hulls are a by-product of soybean oil and meal processing. They are typically regarded as low quality and inexpensive fillers which lack any significant nutritional value.
Ground Yellow Corn
Ground Yellow Corn
Ground yellow corn is a cereal grain which provides a modest amount of vitamins, minerals, and plant based protein. It also happens to be one of the most controversial ingredients in pet food.
Proponents of corn claim that corn is highly digestible and an excellent source of protein, energy, vitamins, minerals, and essential fatty acids.
Opponents however believe that positive claims in regards to corn are either half-truths or completely false, we'll discuss a few of the opposing arguments.
In regards to digestibility, the claims of "highly digestible" are only true if corn is processed into a meal or flour and subsequently cooked. In regards to the protein contribution, we must note that corn is a plant based protein which does not contain all of the necessary amino acids required by pets to sustain life. Therefore substituting corn for meat is an unsuitable substitution and actually degrades the overall protein quality of the product.
Finally, we'll discuss the claims about vitamins and minerals in corn. Although corn does provide many vitamins and minerals, it not necessarily an exceptional ingredient in this regards. There are many other ingredients which are more complete and biologically appropriate. Therefore the usage of corn as the primary ingredient in pet food should certainly warrant further questioning.
Turkey By-Product Meal
Turkey By-Product Meal
Turkey by-product meal is produced by cooking turkey by-products using a process called rendering. By-products are defined by AAFCO as the "non-rendered, clean parts, other than meat, derived from slaughtered mammals." Thus, turkey by-products contain nearly all parts of turkeys which are typically not consumed by humans. These parts include the liver, lung, spleen, kidney, stomach, blood, intestine, bone, etc.
Like other meat by-products, turkey by-products are considered controversial, mainly because they are inexpensive ingredients which consumers have equated with slaughterhouse waste. However, manufactures and many experts claim that animal by-products are unjustly criticized. Proponents state that "named" by-products, such as turkey by-products, supply many important nutrients required by pets.
Chicken By-Product Meal
Chicken By-Product Meal
Chicken by-product meal is produced by cooking chicken by-products using a process called rendering. By-products are defined by AAFCO as the "non-rendered, clean parts, other than meat, derived from slaughtered mammals." Thus, chicken by-products contain nearly all parts of chickens which are typically not consumed by humans. These parts include the liver, lung, spleen, kidney, stomach, blood, intestine, bone, etc.
Like other meat by-products, chicken by-products are considered controversial, mainly because they are inexpensive ingredients which consumers have equated with slaughterhouse waste. However, manufactures and many experts claim that animal by-products are unjustly criticized. Proponents state that "named" by-products, such as chicken by-products, supply many important nutrients required by pets.
Poultry By-Product Meal
Poultry By-Product Meal
Poultry by-product meal is a controversial ingredient because the source animal is not specified. Anonymous ingredients such as poultry by-product meal are typically low-quality ingredients in comparison to named protein by-product meals (e.g. chicken by-product meal, turkey by-product meal, duck by-product meal).
Animal Fat (Preserved With Mixed Tocopherols)
Animal Fat (Preserved With Mixed Tocopherols)
Animal fat is a by-product of tissue rendering. The source animal is not specific and therefore we cannot be certain that the source does not include diseased animals or even euthanized dogs and cats.
Here are some of the controversial ingredients used only by Hill's Science Diet.
Liver
Liver
Liver is a controversial ingredient because the source animal is not specified. Anonymous animal ingredients are typically very low quality and may contain almost any animal, including dogs and cats!
Caramel
Caramel
Caramel is a widely used natural food colorant. The concentrated form of caramel is typically listed as caramel color and has been linked to cancer in laboratory animals. Since our pets do not care about food color, caramel is an unnecessary addition with possible health risks.
Corn Flour
Corn Flour
Corn flour a ground cereal grain which provides a modest amount of vitamins, minerals, and plant based protein. It also happens to be one of the most controversial ingredients in pet food.
Proponents of corn claim that corn is highly digestible and an excellent source of protein, energy, vitamins, minerals, and essential fatty acids.
Opponents however believe that positive claims in regards to corn are either half-truths or completely false, we'll discuss a few of the opposing arguments.
In regards to digestibility, the claims of "highly digestible" are only true if corn is processed into a meal or flour and subsequently cooked. In regards to the protein contribution, we must note that corn is a plant based protein which does not contain all of the necessary amino acids required by pets to sustain life. Therefore substituting corn for meat is an unsuitable substitution and actually degrades the overall protein quality of the product.
Finally, we'll discuss the claims about vitamins and minerals in corn. Although corn does provide many vitamins and minerals, it not necessarily an exceptional ingredient in this regards. There are many other ingredients which are more complete and biologically appropriate. Therefore the usage of corn as the primary ingredient in pet food should certainly warrant further questioning.
Iron Oxide
Iron Oxide
Iron oxide is an FDA approved natural food coloring agent. It's commonly found in rusting metal and provides a reddish-brown color.
We believe food colorants are unnecessary ingredients in pet food. Other than potential harm, food colorants do not provide any nutritional value. These type of ingredients are used only to make the food look appealing to humans.
Pork Plasma
Pork Plasma
Pork plasma is the colorless fluid part of a pig's blood. It may sound disgusting, but it's actually very nutritious for pets. Regardless of the nutritional aspects, consumers are shocked by this ingredient, which is why pork plasma is considered a controversial ingredient.
Poultry Fat
Poultry Fat
Poultry fat is a by-product of poultry tissue rendering. Poultry fat is a controversial ingredient because the specific protein is not specified. Such ingredients are typically low-quality in comparison to named poultry fats (e.g. chicken fat, turkey fat).
Animal Liver
Animal Liver
Animal liver is a controversial ingredient because the source animal is not specified. Anonymous animal ingredients are typically very low quality and may contain almost any animal, including dogs and cats!
Wheat Gluten
Wheat Gluten
Wheat gluten is the main protein of wheat. Although wheat gluten is mostly protein, wheat gluten is considered controversial because it significantly boosts the protein content of the product. This is undesirable because plant based protein does not provide the same amino acid profile as meat based protein.
Caramel Color
Caramel Color
Caramel color is a concentrated form of caramel, a natural food colorant. Caramel color has been linked to cancer in laboratory animals. Since our pets do not care about food color, caramel color is an unnecessary addition with possible health risks.
Tomato Pomace
Tomato Pomace
Tomato pomace is a by-product of tomato manufacturing. It's considered a controversial ingredient because many people believe it is an inexpensive low quality filler. However, tomato pomace provides a notable amount of dietary fiber, B vitamins, Lycopene, and vitamin A. Although it is a very inexpensive ingredient, it is not nutritionally empty.
Beef By-Products
Beef By-Products
By-products are defined by AAFCO as the "non-rendered, clean parts, other than meat, derived from slaughtered mammals." Thus, beef by-products contain nearly all parts of the beef which are typically not consumed by humans. These parts include the liver, lung, spleen, kidney, stomach, blood, intestine, bone, etc.
Like other meat by-products, beef by-products are considered controversial, mainly because they are inexpensive ingredients which consumers have equated with slaughterhouse waste. However, manufactures and many experts claim that animal by-products are unjustly criticized. Proponents state that "named" by-products, such as beef by-products, supply many important nutrients required by pets.
Pork By-Products
Pork By-Products
By-products are defined by AAFCO as the "non-rendered, clean parts, other than meat, derived from slaughtered mammals." Thus, pork by-products contain nearly all parts of pork which are typically not consumed by humans. These parts include the liver, lung, spleen, kidney, stomach, blood, intestine, bone, etc.
Like other meat by-products, pork by-products are considered controversial, mainly because they are inexpensive ingredients which consumers have equated with slaughterhouse waste. However, manufactures and many experts claim that animal by-products are unjustly criticized. Proponents state that "named" by-products, such as pork by-products, supply many important nutrients required by pets.
Dried Tomato Pomace
Dried Tomato Pomace
Dried tomato pomace is a by-product of tomato manufacturing. It's considered a controversial ingredient because many people believe it is an inexpensive low quality filler. However, tomato pomace provides a notable amount of dietary fiber, B vitamins, Lycopene, and vitamin A. Although it is a very inexpensive ingredient, it is not nutritionally empty.
Pea Protein Concentrate
Pea Protein Concentrate
Pea protein concentrate is produced by removing the starchy parts of peas. Pea protein concentrate is considered controversial because it provides a substantial plant based protein boost. This boost is undesirable because plant based protein is typically lower in biological value when compared to meat based proteins.
Soybean Protein Isolate
Soybean Protein Isolate
Soy protein isolate is a highly refined/purified form of soy bean protein. Roughly 90% of soy protein isolate is protein. The inclusion of non-meat protein typically degrades the overall quality of protein in the recipe. This degradation is due to the inferior amino acid profile of plant based proteins.
We believe that certain pet food ingredients are linked to adverse health affects; these ingredients are classified as harmful.
Purina Cat Chow and Hill's Science Diet both use the following harmful ingredients in many of their products:
Menadione Sodium Bisulfite Complex
Menadione Sodium Bisulfite Complex
Menadione sodium bisulfite complex is a synthetic version of vitamin K that has been linked to many health concerns. Research has suggested possible toxic reactions in liver cells and red blood cells among other serious problems. In fact, one large chemical supplier warns, "The substance is toxic to kidneys, lungs, liver, mucous membranes. Repeated or prolonged exposure to the substance can produce target organs damage."
Here are some of the harmful ingredients used only by Purina Cat Chow.
Blue 2
Blue 2
Blue 2 is an artificial dye which can increase the likelihood of tumors according to the Center for Science in the Public Interest. Like other dyes, blue 2 does not provide any nutritional value.
Red 40
Red 40
Red 40 is the most widely used artificial dye in consumer goods. Studies have shown that red 40 may accelerate the appearance of immune-system tumors in mice, cause allergy-like reactions and trigger hyperactivity in children.
Yellow 5
Yellow 5
Yellow 5 is an artificial dye which may be contaminated with several cancer-causing chemicals. Like other dyes, yellow 5 does not provide any nutritional value.
Product Safety: Recall History of Purina Cat Chow & Hill's Science Diet?
According to our records, Purina Cat Chow has never been recalled.
Hill's Science Diet has been recalled 2 times.
Jan. 31, 2019: elevated levels of Vitamin D
March 20, 2019: elevated levels of Vitamin D
Price Comparison: Which Brand Is More Expensive?
Dry Dog Food
Purina Cat Chow
Hill's Science Diet
Per Pound
$1.38
$2.83
Per Calorie
$0.0008
$0.0018
Dry Cat Food
Purina Cat Chow
Hill's Science Diet
Per Pound
$2.03
$4.17
Per Calorie
$0.0013
$0.0024
The average cost-per-lb is heavily influenced by the varying amounts of moisture present in each brand's food products (wet vs. dry food, dry vs. freeze-dried food, etc). However, the average cost-per-kcal eliminates the influence of moisture. Therefore, the average cost-per-kcal is the better metric to consider.
If you'd like to calculate the average cost-per-day or cost-pet-year of feeding Purina Cat Chow or Hill's Science Diet, input your pet's weight into our cost analyzer widget.
Averages price data can identify whether or not there exists a significant price difference between two brands. However, the actual price that you'll pay for Purina Cat Chow or Hill's Science Diet will depend on your shopping habits.
Cost Analyzer Widget
Cost of Feeding Purina Cat Chow
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Cost of Feeding Hill's Science Diet
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Pet owners who use our price comparison feature typically save more than 25% off retail prices for Purina Cat Chow and Hill's Science Diet. In addition, we currently have some great coupons for our readers.
Disclosure: PawDiet has an affiliate relationship with stores featured (or linked-to) in this article. We are compensated for referring customers. Thank you for shopping with our retail partners!
Where To Buy Purina Cat Chow Pet Foods
You can purchase Purina Cat Chow pet foods from the following stores:
8 Recipes In-Stock Today
3 Recipes In-Stock Today
7 Recipes In-Stock Today
Where To Buy Hill's Science Diet Pet Foods
You can purchase Hill's Science Diet pet food products from these retailers: