Why do people on animal-based diets not eat vegetables?

December 22, 2025 •

4 min read

Proponents of the strict carnivore diet, a prominent form of animal-based eating, often claim significant improvements in health issues after eliminating all plant matter. This trend prompts a closer look into why do people on animal-based diets not eat vegetables, and what the rationale is behind such a restrictive eating pattern.

Quick Summary

Individuals following animal-based diets often avoid vegetables due to concerns over plant antinutrients, perceived gut irritation, inflammation, and potential triggers for autoimmune conditions. This elimination-based approach aims to simplify the diet and is particularly strict on the carnivore diet.

Key Points

Antinutrient Avoidance: Followers eliminate vegetables to avoid compounds like lectins, oxalates, and phytates, which they believe interfere with nutrient absorption and cause health problems.
Digestive and Inflammatory Healing: A core motivation is to address gut health problems, reduce inflammation, and calm autoimmune conditions by removing all potential plant irritants.
Focus on Bioavailability: The diet emphasizes consuming highly bioavailable nutrients from animal sources, such as heme iron and Vitamin B12, suggesting these are superior to plant-derived alternatives.
Nutrient Trade-offs: This approach sacrifices fiber and key vitamins like Vitamin C, found primarily in vegetables, creating potential nutritional deficiencies.
Carnivore vs. Animal-Based: The strictest form, the carnivore diet, bans all plants, while some versions of the animal-based diet permit low-toxicity fruits and honey.
Ancestral Perspective: The diet is rooted in the belief that human ancestors primarily consumed meat and that humans are better adapted to an all-animal diet.

The Core Philosophy: Elimination for Health

For those on a strict animal-based or carnivore diet, the decision to eliminate vegetables is based on the philosophy that plants are not essential for human health and may even cause harm. This view is a sharp departure from mainstream nutritional advice, which has historically promoted a diet rich in fruits and vegetables. The core belief is rooted in ancestral eating patterns, suggesting that humans evolved primarily as facultative carnivores, prioritizing nutrient-dense animal foods and only consuming plants when necessary.

Concerns Over Plant Antinutrients

One of the most frequently cited reasons for avoiding vegetables is the presence of 'antinutrients'—plant defense chemicals that can interfere with nutrient absorption and cause digestive distress. Proponents argue that while animals have evolved to handle these compounds, humans may not be as well-adapted, especially in modern diets that include large quantities of plant foods.

Common Plant Antinutrients

Lectins: Found in beans, grains, and some vegetables, lectins are proteins that can bind to the gut lining and disrupt nutrient absorption. In high concentrations or with improper preparation, they can lead to digestive issues.
Oxalates: Present in spinach, rhubarb, and other leafy greens, oxalates can bind to minerals like calcium and magnesium, inhibiting their absorption. In susceptible individuals, high oxalate intake can also increase the risk of kidney stones.
Phytates (Phytic Acid): Primarily found in the seeds, grains, and legumes, phytates can block the absorption of key minerals like iron, zinc, and calcium.
Saponins: These compounds, found in many plants including some vegetables, have been shown to interfere with digestive enzymes and nutrient absorption.
Glucosinolates: Found in cruciferous vegetables like broccoli and cabbage, these compounds can interfere with thyroid function when consumed in large amounts.

The Focus on Gut Health and Inflammation

Many followers turn to an animal-based diet to address specific health issues, particularly those related to gut health, inflammation, and autoimmunity. By completely removing all potential plant irritants, they aim to create an elimination diet that helps identify and resolve food sensitivities. Anecdotal reports and some clinical settings show improvements in conditions like psoriasis, eczema, and other autoimmune disorders after removing all plant foods. This suggests that for some individuals, certain plant compounds may trigger an inflammatory response.

The Difference Between 'Animal-Based' and 'Carnivore'

It is important to distinguish between the two related dietary approaches, as they treat vegetables differently. The strict carnivore diet, popularized by figures like Dr. Shawn Baker, excludes all plant products without exception. The animal-based diet, more commonly associated with Paul Saladino, is slightly less restrictive and often includes low-toxicity plant foods, such as fruits and honey.

Table: Comparison of Diet Approaches to Vegetables


Diet Approach	Vegetable Inclusion	Rationale for Inclusion/Exclusion
Strict Carnivore	Zero vegetables allowed.	All plant matter is considered potentially inflammatory or toxic due to antinutrients and other compounds.
Animal-Based	Limited, low-toxicity plant foods (often fruits) may be included.	Focuses on minimizing antinutrient exposure rather than complete elimination, selecting less toxic plant options.
Standard Diet (Omnivore)	Encourages a wide variety of vegetables and plants.	Generally emphasizes the benefits of plant fiber, vitamins, and minerals, often overlooking concerns about antinutrients.

Concerns and Critiques of Eliminating Vegetables

While proponents praise the health improvements they attribute to the elimination of vegetables, critics and mainstream medical professionals raise significant concerns. A key issue is the complete lack of fiber, a nutrient found only in plant foods that is critical for digestive health. The absence of fiber can lead to constipation and may negatively impact the gut microbiome. Furthermore, excluding all vegetables can lead to a deficiency of certain micronutrients, most notably Vitamin C. Critics also point to the high saturated fat content of some animal-based diets, which can raise LDL (bad) cholesterol levels and increase heart disease risk. It is essential for individuals to consider these risks and consult with a healthcare professional before adopting such a restrictive diet.

Conclusion

In conclusion, people on animal-based diets avoid vegetables primarily to eliminate plant antinutrients, mitigate potential inflammatory responses, and resolve digestive issues. This rationale, while largely based on anecdotal evidence and personal experimentation rather than comprehensive, long-term studies, is a powerful motivator for adherents. The strictness of vegetable elimination varies between the carnivore and animal-based approaches. While proponents claim significant health benefits, it is crucial to recognize the potential long-term risks, including nutrient deficiencies and gut health issues, that can arise from excluding an entire food group. As with any highly restrictive diet, careful consideration and professional guidance are paramount. For further reading on the complex topic of antinutrients, consult reliable sources like the NIH.

Note: The effectiveness and long-term safety of the carnivore diet and strict animal-based diets are still under debate within the scientific and medical communities. The information provided here summarizes the stated reasons and philosophies of diet adherents.

Frequently Asked Questions

Antinutrients are natural compounds found in plants, such as lectins, oxalates, and phytates, that can bind to minerals and nutrients, reducing their absorption. For some on animal-based diets, these compounds are seen as potentially harmful irritants to the gut.

Yes, following a strict animal-based or carnivore diet can lead to deficiencies in certain nutrients, most notably dietary fiber and Vitamin C, which are found almost exclusively in plants. Supplementation or careful inclusion of some plant foods in less strict versions may be necessary.

No. The carnivore diet is a specific type of animal-based diet that strictly eliminates all plant foods. Some who follow a broader 'animal-based' diet, like Paul Saladino's approach, may include select low-toxicity plant foods, such as fruits and honey.

Eliminating all plant foods removes dietary fiber, a key source of food for beneficial gut bacteria. The long-term effects of this on the gut microbiome are still being studied, but it can lead to a significant change in bacterial balance.

For some individuals who have used the diet as an elimination tool, reintroducing vegetables can trigger a reaction, providing direct subjective evidence of a food sensitivity. For others, a gradual reintroduction may be possible without issue.

Mainstream health professionals express concerns about the long-term safety of the carnivore diet, citing risks like nutrient deficiencies, lack of fiber, and potentially high saturated fat and cholesterol intake. It is important to consult with a healthcare provider and monitor health markers.

While fresh organ meats contain some Vitamin C, the amount is significantly lower than in most fruits and vegetables. Relying on meat alone may not provide adequate Vitamin C, and deficiency (scurvy) is a risk.