Lung
Last updated: March 18, 2026
In This Article
Quick Summary
Lung Excellent for training treats due to its light, airy texture when dried and very low fat content (2-3%). Less nutrient-dense than liver or heart, so it works better as a treat ingredient than a primary protein source. Look for species identification (beef lung, pork lung).
What Is Lung?
Lung tissue from mammals. Lower protein density than muscle meat but still nutritious organ meat.
Compare to Similar Ingredients
- vs. beef heart: Both are organ meats. Lung is spongy, low-fat protein, while heart is denser muscle with more CoQ10, taurine, and B vitamins.
Why Manufacturers Add Lung to Dog Food
Lung is used in dog treats and raw food as a light, airy organ meat that's high in protein and rich in iron and B vitamins—its spongy texture makes it an especially popular single-ingredient treat that dehydrates and freeze-dries well while remaining palatable to dogs.
- Organ meat variety
- Cost-effective protein
- Rich in vitamins and minerals
Lung Quality Considerations
When evaluating lung in dog products, it's important to understand protein density, amino acid profile, digestibility, and sourcing quality. Lung tissue is nutritious and digestible but very light — its low density means it can appear higher on an ingredient list than its actual contribution to dietary protein warrants. It's a legitimate protein source, just one where label position is a less reliable volume indicator than usual.
Acceptable organ meat though less nutrient-dense than liver or heart.
Lung: What the Research Shows
Function and Purpose
Primary Function: Novel protein source and treat ingredient from organ meat
Nutritional Profile and Composition
Lung is organ meat (offal) from cattle, pork, or other livestock. It consists primarily of alveolar tissue with associated blood vessels and bronchial structures. Nutritionally, lung provides moderate protein (15-18% fresh weight basis), very low fat (2-3%), and significant moisture content (75-80%).
As organ meat, lung contains higher levels of certain nutrients compared to muscle meat, including iron, B vitamins (especially B12), vitamin A, selenium, and zinc. The spongy texture when dried makes it popular for training treats. Lung is less nutrient-dense than liver or kidney but provides protein variety.
Efficacy and Research
Lung is a digestible protein source suitable for most dogs, though its low fat content means it provides lean protein without substantial energy. For treats, the airy texture creates high-volume, low-calorie options. As a novel protein for dogs with food sensitivities, lung from uncommon sources (bison, venison) may be appropriate.
Quality varies significantly based on sourcing and processing. Human-grade lung from inspected facilities ensures safety and quality. Dried lung treats should have minimal additives. The ingredient provides nutritional variety in rotation diets but shouldn't be a primary protein source due to its lower nutrient density compared to muscle meat.
Moderate - Digestible organ meat with nutritional benefits; quality highly dependent on sourcing and processing
Lung on the Label
How It Appears on Labels
Lung tissue is nutritious and digestible but very low density — it appears higher on ingredient lists than its actual protein contribution warrants because its weight per volume is much lower than muscle meat. Label position is a less reliable volume indicator for lung than for most other protein sources. Common label names:
- lung
- beef lung
- pork lung
- dried lung
- lung meat
Positioning and Context
Common in treats, training rewards, and some novel protein formulas; positioning varies by product type
Quality Indicators
Signs of quality sourcing and use:
- Species specified (beef, pork, bison)
- Human-grade or USDA inspected
- Single ingredient treats (dried lung only)
- Source country disclosed
Red Flags
Potential concerns to watch for:
- Generic 'lung' without species identification
- Unknown sourcing or country of origin
- Combined with numerous additives in treats
- Used as primary protein in formulas (suggests low-quality nutrition)
Decent organ meat for variety, though not as nutrient-dense as liver or heart.
Frequently Asked Questions
Why is lung used in dog treats?
Lung makes excellent training treats due to its unique properties. When dried, the spongy alveolar tissue creates a light, airy texture that's easy to break into small pieces. It's very low in fat (2-3%) so it's low-calorie—ideal for frequent training rewards. Dogs find the flavor appealing. The light weight means more treats per bag, making it economical for training purposes.
Is lung as nutritious as liver or heart?
No—lung is less nutrient-dense than liver or heart. Liver is a vitamin powerhouse (A, B12, iron, copper). Heart provides exceptional taurine and CoQ10. Lung offers moderate protein (15-18%), some B vitamins and iron, but at lower concentrations. Lung is valued more for its unique texture (great for treats) and as part of whole-prey variety rather than as a nutritional superstar.
Can dogs eat lung regularly?
Yes, lung is safe for regular consumption. Unlike liver, there are no vitamin toxicity concerns with lung. It's lean, digestible, and provides variety in the diet. As treats, dried lung can be fed daily during training. In complete diets, lung can contribute to the organ meat portion (though liver and heart offer more nutritional benefit). Quality and sourcing matter—look for USDA-inspected sources.
Related Reading
Learn more: The Real Benefits of Organ-Based Nutrition for Dogs · Beef Liver for Dogs: Nutrient-Dense Superfood
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