Hill’s Science Diet (Dry) Review

The Hill’s Science Diet dry product range is made of 27 recipes which all receive 4-stars.

It is formulated to meet the nutritional levels established by AAFCO cat food nutrient profiles for all life stages — kitten, adult and senior cats. 

Hill’s Science has a variety of dry products tailored to a cat’s individual needs including health conditions such as diabetes and kidney disease.

The table below shows each recipe in the range including our rating and the AAFCO nutrient profile: Growth (kitten), Maintenance (adult), All Life Stages, Supplemental or Unspecified.

Recipe and Label Analysis

Hill’s Science Diet Adult 11+ Chicken Recipe dry cat food was selected to represent the other products in the line for a detailed recipe and nutrient analysis.

Label and nutrient data below are calculated using dry matter basis.

Ingredients Analysis

The first ingredient is chicken. Chicken is considered “the clean combination of flesh and skin… derived from the parts or whole carcasses of chicken”. ¹

Chicken is naturally rich in the 11 essential amino acids required by a cat to sustain life.

The second ingredient is whole grain wheat. Like corn, wheat is an inexpensive and controversial cereal grain. And aside from its energy content, this grain is of only modest nutritional value to a cat. For this reason, we do not consider wheat a preferred component in any cat food.

The third ingredient is corn gluten meal. Gluten is the rubbery residue remaining once corn has had most of its starchy carbohydrate washed out of it. Although corn gluten meal contains 60% 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 cat food.

The fourth ingredient is chicken fat. Chicken fat is obtained from rendering chicken, a process similar to making soup in which the fat itself is skimmed from the surface of the liquid.

Chicken fat is high in linoleic acid, an omega-6 fatty acid essential for life. Although it doesn’t sound very appetizing, chicken fat is actually a quality ingredient.

The fifth ingredient is brewers rice. Brewers rice is a cereal grain by-product consisting of the small fragments left over after milling whole rice. Aside from the caloric energy it contains, this item is of only modest nutritional value to a cat.

The sixth ingredient is egg product, an unspecified (wet or dry?) form of shell-free eggs. Quality can vary significantly. Lower grade egg products can even come from commercial hatcheries – from eggs that have failed to hatch. In any case, eggs are easy to digest and have an exceptionally high biological value.

The seventh ingredient is flaxseed, 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 cat food.

The eighth ingredient is dried beet pulp. Beet pulp is a controversial ingredient, a high fiber by-product of sugar beet processing. Some denounce beet pulp as an inexpensive filler while others cite its outstanding intestinal health and blood sugar benefits.

We only call your attention here to the controversy and believe the inclusion of beet pulp in reasonable amounts in most cat foods is entirely acceptable.

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 the product.

However, this recipe does contain wheat gluten. Gluten is the rubbery residue remaining once wheat has had most of its starchy carbohydrate washed out of it.

Compared to meat, glutens are inferior plant-based proteins low in some of the essential amino acids dogs need for life.

This inexpensive plant-based ingredient can significantly boost the total protein reported on the label — a factor that must be considered when judging the actual meat content of this cat food.

Nutrient Analysis

Based on its ingredients alone, Hill’s Science Diet Adult 11+ Chicken Recipe looks like an above-average dry product.

The dashboard displays a dry matter protein reading of 32.7%, a fat level of 22.5% and an estimated carbohydrate level of 37%.

As a group, the brand features an average protein content of 33.4% and a mean fat level of 19.6%. Together these figures suggest a carbohydrate content of 35.4% for the overall product line, alongside a fat-to-protein ratio of 59%.

This means the Hill’s Science Diet dry product line contains below-average protein, above-average carbs and above-average fat when compared to typical dry cat food.

Has Hill's cat food been recalled in the past?

Yes, there have been several recalls. Details can be found on the Dog Food Advisor, but in summary:

In 2007, there was an industry-wide recall which impacted Hill’s Science, due to food being contaminated with melamine. The contamination resulted in severe sickness and death among cats and dogs. 

In 2014, there was another recall of Hill’s Science Diet dog food, due to potential salmonella contamination.

A year later, Hill’s initiated a market withdrawal which affected several dog food varieties. The recall was a result of labeling issues. 

In late 2019, Hill’s was also forced to recall canned dog food from their Prescription and Science Diet lines. This was a result of unusually high vitamin D content. High vitamin D levels cause blood calcium to rise, resulting in organ failure and possibly death. 

However, this did not just affect Hill’s Science Diet. About two months later, other pet food brands were recalled over vitamin D-related issues.

You can view a complete list of all cat food recalls since 2021 here.

To stay on top of any cat food product recalls, sign up for our free email alerts, here.

About

Hill’s Pet Nutrition is an international pet food brand that’s known for selling scientifically developed foods.

The company was first founded in 1907 by Burton Hill as a rendering service with a contract to dispose of dead and lame animals in Topeka, Kansas.

It has come a long way since, now employing a team of more than 220 veterinarians, nutritionists, technicians, and food scientists to develop pet foods in the Hill research facility that’s still located in Topeka.