Understanding Why Do Meats Have No Carbs?

October 28, 2025 •

4 min read

Although living animals store carbohydrates as glycogen in their muscles, fresh, unprocessed meat contains virtually no carbs. The answer to why do meats have no carbs? lies in a fascinating biological process that occurs after slaughter, providing a key nutritional fact for those following low-carb diets.

Quick Summary

Fresh, unprocessed meat lacks carbohydrates because the glycogen stored in muscle tissue is converted to lactic acid after an animal is slaughtered. This post-mortem process depletes the energy reserves, resulting in a carb-free final product, a crucial fact for followers of ketogenic and other low-carb diets.

Key Points

Glycogen Depletion: The primary reason fresh meat contains no carbs is that the glycogen stores in an animal's muscles are consumed and converted to lactic acid after slaughter.
Post-Mortem Process: The conversion of muscle to meat involves anaerobic glycolysis, which depletes energy reserves and lowers the pH of the tissue.
Organ Meat Exception: Organ meats, particularly liver, retain small amounts of glycogen and therefore contain a few grams of carbohydrates.
Processed Meat Warning: Processed meats often contain hidden carbohydrates from added sugars, starches, or fillers; consumers should always check labels.
Dietary Relevance: The carb-free nature of fresh meat makes it a fundamental component for low-carb and ketogenic diets, supporting protein and fat intake without adding carbohydrates.
Nutrient-Dense Protein: Beyond being carb-free, fresh meat is a high-quality source of complete protein and essential micronutrients like B vitamins, iron, and zinc.

The Science of Glycogen and Muscle

To understand why meat is carb-free, we must first look at the role of glycogen in living animals. Glycogen is the animal equivalent of starch in plants; it serves as a complex carbohydrate storage form, providing a ready source of glucose for energy. The body stores most of its glycogen in the liver and skeletal muscles. In a living animal, muscle glycogen powers muscle contractions, especially during periods of high activity.

Unlike plants, which produce energy through photosynthesis and store it as starches and sugars, animals acquire energy by consuming other organic matter. Their metabolic processes are fundamentally different. While animals require carbohydrates in their diet to function, these are primarily used for immediate energy or converted into glycogen for short-term storage, not integrated into the muscle tissue's structure as a long-term carb source.

The Post-Mortem Glycogen Depletion Process

Once an animal is slaughtered, its metabolic processes change dramatically. Oxygen is no longer supplied to the tissues, and the conversion of muscle to meat begins. Here’s what happens:

Enzyme Action: Enzymes within the muscle cells begin to break down the stored glycogen in a process called anaerobic glycolysis.
Lactic Acid Production: The breakdown of glycogen produces lactic acid. This acid buildup causes a decrease in the muscle tissue's pH.
Rigor Mortis: This chemical change leads to rigor mortis, the stiffening of the muscles. The process continues until the glycogen supply is nearly exhausted and the low pH inactivates the enzymes.
Depletion: By the time the meat is butchered, packaged, and reaches the consumer, the glycogen has been completely or almost completely depleted. This is why a nutrition label for fresh meat, like a steak or chicken breast, lists 0 grams of carbohydrates.

This depletion is a natural and necessary part of the meat tenderization process and explains the absence of carbs in the final product. Even wild game, where hunting can cause significant stress and physical exertion, will have depleted glycogen stores due to the animal's struggle.

Exceptions to the Rule: Organ Meats and Processed Products

While the “zero carb” rule holds for most fresh muscle meat, it's not universal across all animal products. A few key exceptions should be noted:

Organ Meats: Organs like the liver act as primary glycogen storage depots. Because of this, liver retains a small amount of carbohydrates even after processing. For example, beef liver contains about 3–4 grams of carbs per 100 grams. While still relatively low-carb, this is a notable exception for those on a strict zero-carb or carnivore diet.
Shellfish: Some types of seafood, particularly shellfish like oysters and mussels, naturally contain small amounts of carbohydrates. Oysters can contain around 5 grams of carbs per 100 grams, while mussels have approximately 7 grams.
Processed Meats: Cured and processed meats are the most common source of hidden carbohydrates. Manufacturers often add ingredients containing carbs, such as sugar, starch, breadcrumbs, or fillers, to improve flavor, texture, or shelf life. Always check the nutrition label for products like sausage, deli meats, and pre-packaged bacon.

Why This Matters for Your Diet

For individuals on low-carbohydrate diets like the ketogenic (keto) or carnivore diet, the carb-free nature of fresh meat is a foundational principle. It allows them to consume a nutrient-dense source of protein and fat without impacting their carbohydrate macros or disrupting ketosis. This is particularly important for keto dieters who need to remain under a very strict daily carb limit. Meat provides a high-quality, complete protein source, offering all the essential amino acids the body needs for muscle building and repair. Furthermore, it is a powerhouse of micronutrients, including iron, zinc, and B vitamins, that are essential for overall health.

Fresh Meat vs. Processed Meat: Carb Comparison

For a clearer picture, here is a comparison of carbohydrate content in various animal products (per 100g approximate values):


Type of Meat	Carbohydrate Content (g)	Notes
Fresh Beef Steak	0	Glycogen depleted post-slaughter.
Fresh Chicken Breast	0	Glycogen depleted post-slaughter.
Fresh Pork Chops	0	Glycogen depleted post-slaughter.
Beef Liver	3–4	Small amount of glycogen retained.
Oysters	~5	Natural carb content in shellfish.
Mussels	~7	Natural carb content in shellfish.
Processed Sausage	2–3 (approx)	Contains added fillers or sugar.
Processed Bacon	0–1 (approx)	Can contain added sugar.

Nutritional Profile Beyond Carbs

It is important to remember that the value of meat extends far beyond its lack of carbohydrates. The nutritional density of meat is considerable. A typical serving offers a substantial amount of high-quality protein, which is vital for maintaining and building muscle mass. It is also an excellent source of essential fats, B vitamins (particularly B12, crucial for nerve function and red blood cell production), iron, and zinc. The bioavailability of these nutrients in meat is often higher than in plant-based sources, meaning the body can absorb and utilize them more efficiently.

Conclusion: The Final Word on Carb-Free Meat

The reason behind fresh meat's carb-free nature is a straightforward consequence of a natural post-slaughter process where muscle glycogen is consumed and converted to lactic acid. This biological fact makes fresh, unprocessed meat a zero-carb food, a cornerstone of many restrictive diets. While it's important to remember the exceptions for organ meats, shellfish, and processed products, fresh meat remains a reliable, nutrient-dense, and carb-free option. For anyone monitoring their carbohydrate intake, understanding this fundamental principle of food science is key to making informed dietary choices.

The Role of Carbohydrates in Other Animals

For additional context, consider the significant role of carbohydrates in livestock diets. Ruminant animals like dairy cattle consume a large amount of carbohydrates from forages, which their specialized digestive system (the rumen) uses to produce energy. A balanced diet with an appropriate mix of simple and complex carbohydrates is essential for their health and productivity. This highlights the difference between an animal's diet and the final nutritional composition of its muscle tissue once it becomes meat. Learn more about the biology of muscles and their energy sources here..

Frequently Asked Questions

No, not all meat is completely zero-carb. While fresh, unprocessed muscle meats are virtually carb-free, certain organ meats like liver and some shellfish (e.g., oysters, mussels) contain small amounts of carbohydrates.

Processed meats, such as sausage, deli meats, and hot dogs, often contain added ingredients like starches, fillers, or sugar during their preparation, which introduces carbohydrates to the final product. Always check the nutritional label.

Glycogen is a complex carbohydrate that serves as the energy storage form in animals. It is primarily stored in the liver and skeletal muscles of a living animal, providing a ready source of glucose.

Cooking meat does not destroy or remove carbohydrates. The carbohydrates (glycogen) are already depleted during the post-slaughter process before the meat is cooked. What you eat is already virtually carb-free.

Unlike muscle meat, shellfish retain some carbohydrates naturally. For example, oysters and mussels contain a few grams of carbohydrates per serving, making them an exception to the general rule.

Yes, fresh, unprocessed pork is also a carb-free meat. As with other muscle meats, the glycogen stores are depleted during the post-mortem process.

Wild game meat is also carb-free. The exertion and stress of the hunt often lead to a rapid depletion of muscle glycogen, leaving no carbohydrates in the meat that reaches your plate.