Purina Pro Plan and Hill's Science Diet are both veterinary-trusted, research-backed dog food brands. These science-driven companies take similar approaches but have distinct differences. Here's how they compare.
Brand Overview
Purina Pro Plan
- Founded: 1986 (Purina since 1894)
- Headquarters: St. Louis, Missouri
- Philosophy: Performance nutrition through science
- Parent Company: Nestlé Purina
- Price Point: Premium
- Research: Extensive, published studies
Hill's Science Diet
- Founded: 1939
- Headquarters: Topeka, Kansas
- Philosophy: Clinical nutrition science
- Parent Company: Colgate-Palmolive
- Price Point: Premium to high premium
- Research: Extensive, veterinary-focused
Quick Comparison
| Factor | Purina Pro Plan | Hill's Science Diet |
|---|---|---|
| Average Rating | 4.71/5 | 4.6/5 |
| Price Range | $$ - $$$ | $$$ |
| Live Probiotics | Yes | No |
| Prescription Lines | Yes | Yes (extensive) |
| Research Depth | Extensive | Extensive |
| Made in USA | Yes | Yes |
Ingredient Philosophy
Both brands prioritize science over marketing:
Purina Pro Plan
- Real meat first ingredient
- Live probiotics in many formulas
- Research-proven formulations
- Performance-focused options
- Balanced approach to ingredient quality
Hill's Science Diet
- Clinically proven nutrition
- Ingredients chosen for function
- May include by-products
- Focus on therapeutic nutrition
- Precise nutrient profiles
Nutritional Comparison
Protein Content
- Purina Pro Plan: 26-30% (varies by formula)
- Hill's Science Diet: 21-26% (adult formulas)
- Pro Plan generally slightly higher
Fat Content
- Purina Pro Plan: 16-20%
- Hill's Science Diet: 13-16%
- Pro Plan offers more fat for active dogs
Key Differences
Purina Pro Plan:
- Live probiotics (guaranteed)
- Higher protein/fat in Sport line
- EPA for joint mobility
- Focus on performance
Hill's Science Diet:
- Clinically tested formulas
- Emphasis on therapeutic nutrition
- Perfect Weight technology
- Strong prescription line
Product Lines
Purina Pro Plan
- Complete Essentials: Standard adult
- Sensitive Skin & Stomach: Sensitivities
- Sport 30/20: Active dogs
- Large/Small Breed: Size-specific
- Puppy/Adult 7+: Life stages
- Veterinary Diets: Prescription
Hill's Science Diet
- Adult: Standard maintenance
- Perfect Weight: Weight management
- Sensitive Stomach & Skin: Sensitivities
- Oral Care: Dental health
- Large/Small Breed: Size-specific
- Puppy/Mature Adult/Senior: Life stages
- Prescription Diet: Extensive therapeutic (separate line)
Veterinary Prescription Lines
Both offer veterinary therapeutic diets:
Purina Pro Plan Veterinary Diets
- HA (Hydrolyzed)
- EN (Gastrointestinal)
- JM (Joint Mobility)
- OM (Obesity Management)
Hill's Prescription Diet
- Extensive range (industry leader)
- z/d, i/d, k/d, j/d, w/d, and many more
- Most comprehensive therapeutic line
- Gold standard for veterinary nutrition
Hill's has a significant advantage in therapeutic/prescription options.
Price Comparison
Average Cost (30 lb bag)
- Purina Pro Plan Adult: $55-65
- Hill's Science Diet Adult: $65-75
- Purina Pro Plan Sport: $60-70
- Hill's Perfect Weight: $70-80
Hill's typically costs 15-25% more than Purina Pro Plan.
Research and Science
Purina Pro Plan
- Hundreds of published studies
- Feeding trials (AAFCO)
- Peer-reviewed research
- Veterinary nutritionist developed
- Probiotics research specialty
Hill's Science Diet
- Decades of clinical research
- Extensive feeding trials
- Therapeutic nutrition leader
- Veterinary partner programs
- Academic partnerships
Both are among the most researched pet food brands globally.
Who Should Choose Each
Choose Purina Pro Plan If:
- You want live probiotics
- Value slightly lower cost for similar quality
- Have an active/sporting dog
- Want excellent research backing
- Your dog is generally healthy
Choose Hill's Science Diet If:
- May need prescription options later
- Want widest therapeutic coverage
- Trust the clinical nutrition approach
- Don't mind slight premium pricing
- Dog has specific health conditions
For Active Dogs
Purina Pro Plan Advantage
- Sport 30/20 formula
- Higher protein and fat options
- Designed for performance
- Supports working/sporting dogs
Hill's doesn't have dedicated sport lines, giving Pro Plan the edge for active dogs.
For Health Conditions
Hill's Advantage
- Most comprehensive Prescription Diet line
- Decades of therapeutic nutrition expertise
- Wider range of condition-specific foods
- Industry leader in veterinary diets
For dogs needing therapeutic nutrition, Hill's Prescription Diet is often the gold standard.
Our Verdict
For Most Healthy Dogs
Purina Pro Plan offers:
- Excellent nutrition at better value
- Live probiotics benefit
- Great for active dogs
- Strong research backing
Hill's Science Diet Excels For:
- Dogs needing therapeutic diets
- Those who may need Prescription Diet options
- Clinical nutrition needs
- Premium health focus
Both Are Excellent
These are top-tier, vet-recommended brands. Either choice serves most dogs well.
Frequently Asked Questions
Which do most vets recommend?
Both are highly veterinary-recommended. Some vets prefer Hill's for clinical nutrition; others like Pro Plan's probiotics and value. Personal vet experience often influences recommendations.
Is the price difference justified?
For healthy dogs, Purina Pro Plan provides similar quality at lower cost. If you anticipate needing therapeutic diets, Hill's ecosystem (Science Diet to Prescription Diet) may justify the premium.
Which is better for weight loss?
Both have effective weight management formulas. Hill's Perfect Weight is clinically proven. Purina Pro Plan Weight Management also works well. Hill's may have slight edge in research for weight loss specifically.
Do both have probiotics?
Purina Pro Plan includes live probiotics in many formulas (guaranteed at time of feeding). Hill's focuses more on prebiotic fiber for gut health rather than live probiotics.
Can I switch between brands?
Yes, transition gradually over 7-10 days. Both are high-quality, so most dogs adapt well with proper transition.