Why Don't Carnivores Get Scurvy? Unpacking the Science of a Nutrient-Rich Diet

November 2, 2025 •

4 min read

A fascinating biological fact is that almost all animals, with the notable exceptions of primates and guinea pigs, synthesize their own vitamin C. This self-producing ability, along with other metabolic adaptations, helps explain why carnivores don't get scurvy when following an all-meat diet.

Quick Summary

The ability of most animals to internally synthesize vitamin C is the primary reason wild carnivores avoid scurvy. For humans on an all-meat diet, reduced carbohydrate intake lowers their vitamin C requirements, while fresh meat and organ meat provide sufficient bioavailable amounts to prevent deficiency. Cultural and historical evidence from groups like the Inuit supports this dietary approach.

Key Points

Carnivores Synthesize Vitamin C: Most animals can internally produce their own vitamin C, unlike humans and guinea pigs, which is why wild carnivores don't get scurvy.
Lower Human Requirement on Low-Carb Diet: When carbohydrates are eliminated, the body's need for vitamin C decreases significantly, and the available supply from meat is absorbed more efficiently.
Fresh Meat Provides Vitamin C: Fresh, uncooked meat and especially organ meats contain sufficient, bioavailable vitamin C to prevent scurvy in humans, contrary to common belief.
Endogenous Antioxidant Production: In a low-carb state, the body increases its own production of antioxidants like glutathione and uric acid, reducing its reliance on dietary vitamin C.
Historical Context Matters: Cases of historical scurvy, such as among European sailors, were typically due to a lack of fresh food, not meat in general. The Inuit, eating fresh meat and organs, avoided the disease.
Organ Meats are Nutrient Powerhouses: Incorporating nutrient-dense organ meats like liver and kidney is a reliable way for humans on a carnivore diet to ensure adequate vitamin C intake.

The Historical Scurvy Myth: Sailors vs. Inuit

For centuries, scurvy was a feared disease among sailors, famously caused by a lack of fresh fruits and vegetables on long voyages. However, this historical context often fuels misconceptions about modern low-carb or carnivore diets. The key difference lies not just in the absence of produce, but in the specific nature of the meat consumed. European sailors subsisted on preserved, salted, and canned meats, a process that destroys the already minimal vitamin C content. In contrast, Arctic populations like the Inuit traditionally thrived on diets composed almost entirely of animal products, including fresh meat, organs, and fish. They did not develop scurvy because they were consuming fresh, nutrient-dense parts of the animal, often eaten raw or lightly cooked, which retained their vitamin C content.

The GULO Gene: A Tale of Two Species

The primary difference between most animals and humans is the ability to produce vitamin C internally. The synthesis pathway in animals is a multi-step process that starts with glucose and ends with ascorbic acid, the active form of vitamin C. The final, crucial step is catalyzed by an enzyme called l-gulonolactone oxidase (GULO), which is encoded by the GULO gene.

Around 60 million years ago, a mutation rendered the GULO gene non-functional in the ancestors of higher primates, including humans. This meant we, along with guinea pigs and some other species, lost the ability to produce our own vitamin C and became dependent on dietary sources. Carnivorous animals like cats and dogs, however, never lost this ability and can produce all the vitamin C they need in their liver.

The Glucose-Vitamin C Connection

For humans on a low-carbohydrate or carnivore diet, two key factors explain why they can avoid scurvy:

Reduced competition for absorption: Both glucose and vitamin C share the same cellular transport pathways for absorption. On a typical high-carbohydrate Western diet, glucose outcompetes vitamin C for uptake, meaning the body needs a higher dietary intake of vitamin C to absorb enough. By eliminating carbohydrates, the carnivore diet dramatically reduces this competition, allowing even the small amounts of vitamin C found in meat to be absorbed efficiently.
Lower physiological need: With carbohydrates absent, the body's need for vitamin C is significantly lower. Many of vitamin C's roles in a high-carb metabolism are related to managing oxidative stress and inflammation caused by sugar metabolism. In a low-carb, fat-adapted state, the body's oxidative stress is reduced, and it upregulates its own powerful internal antioxidants, such as glutathione and uric acid, which further reduces the reliance on dietary vitamin C.

Where Do Carnivores Get Vitamin C?

While muscle meat contains trace amounts of vitamin C, the most significant animal sources are organ meats and fresh seafood, mirroring the practices of ancestral populations.

Excellent Carnivore Sources of Vitamin C:

Beef Liver: Provides a concentrated dose of vitamins and minerals, including vitamin C.
Beef Spleen: A highly nutrient-dense option with a notable vitamin C content.
Fish Roe: A rich source of not only omega-3 fatty acids but also vitamin C.
Kidney: Contains slightly more vitamin C than liver and is a valuable addition to the diet.

When consuming meat, freshness is crucial, as the vitamin C content is heat-sensitive and degrades during processing, drying, and prolonged cooking.

Carnivore vs. Standard Western Diet: A Comparison of Vitamin C Needs


Feature	Carnivore Diet (Low-Carb)	Standard Western Diet (High-Carb)
Primary Vitamin C Source	Animal products (fresh meat, organs)	Plant-based foods (fruits, vegetables)
Glucose Competition	Very low; efficient vitamin C absorption	High; competition for transport limits absorption
Vitamin C Requirement	Lower due to metabolic adaptation	Higher to compensate for competition
Role of Endogenous Antioxidants	Upregulated; helps manage oxidative stress	Standard function; less critical role due to dietary intake
Risk of Scurvy	Negligible with fresh, whole animal intake	Possible with poor intake of vitamin C foods

The Takeaway for Human Carnivores

The long-standing concern that an all-meat diet will cause scurvy in humans is largely based on a misunderstanding of both human metabolism and nutritional requirements under different dietary conditions. By eliminating the high-carbohydrate foods that compete with vitamin C for absorption and consuming nutrient-dense fresh meats and organ meats, individuals can easily acquire the lower amount of vitamin C needed to prevent deficiency. The success of ancestral groups like the Inuit on similar diets and modern anecdotal evidence from carnivore dieters further supports this conclusion.

For those considering an animal-based diet, prioritizing fresh food sources and incorporating nutrient-rich organ meats is key. Consulting a healthcare professional is also advisable to ensure a transition that addresses individual health needs.

Conclusion

While it is true that humans cannot produce their own vitamin C like most carnivores, modern adherents of a carnivore diet have demonstrated that scurvy is not a foregone conclusion. The combination of consuming fresh, bioavailable vitamin C from meat and organs, coupled with a reduced physiological need resulting from low carbohydrate intake, effectively prevents deficiency. This dietary approach re-frames our understanding of vitamin C needs, showing that the context of the overall diet is far more important than just the amount of a single vitamin consumed.

Frequently Asked Questions

It is highly unlikely for a human consuming a fresh, nutrient-dense carnivore diet to get scurvy. While meat contains less vitamin C than fruits and vegetables, the body’s requirement for it is significantly lower on a low-carb diet, and the vitamin C from animal products is very bioavailable.

Unlike humans, most animals, including carnivores like cats and dogs, have the ability to synthesize their own vitamin C within their bodies, primarily in their liver. Therefore, they do not need to obtain it from dietary sources.

Cooking does destroy some of the vitamin C content in meat, as the vitamin is sensitive to heat. This is why traditional populations that ate all-meat diets often consumed parts of the animal either raw or very lightly cooked.

Yes, historical accounts of the Inuit people, who lived on a diet of fresh meat and fish, demonstrate that it is possible for humans to survive without plant-based foods and avoid scurvy. They consumed all parts of the animal, including the organs, which are rich in nutrients.

In a low-carb diet, the body has lower levels of glucose, which competes with vitamin C for uptake at the cellular level. With less glucose competition, the body can absorb the vitamin C it needs more efficiently, thus lowering the overall dietary requirement.

Organ meats such as liver, kidney, and spleen are excellent sources of vitamin C for human carnivore dieters. These are much more concentrated sources than muscle meat.

Most people on a well-formulated carnivore diet do not need a vitamin C supplement, especially if they are consuming a variety of fresh meats and including organ meats. However, individuals with pre-existing health conditions should consult a doctor before making major dietary changes.