Are Humans Better Suited to Be Carnivores or Herbivores? A Comparison of Meat vs Plant-Based Diets

Biologically speaking, humans are omnivores. This means they have the digestive and metabolic ability to absorb nutrients from foods derived from both plants and animals. 

Despite our evolutionary history as omnivores, many people don’t choose to live as such. Some individuals choose to only eat animal-derived products and eliminate plants, known as the carnivore diet. Others choose to only eat plant-derived foods and exclude all animal products, referred to as a plant-based diet or vegan diet.

When considering both of these restrictive diets in terms of nutrition, health, and long-term feasibility, is the carnivore diet or plant-based diet superior? Is either diet more healthful than the default omnivorous diet?

Carnivore Diet: Protein Power

The carnivore diet consists mostly or entirely of animal based products, such as meat, fish, dairy, and eggs. It eliminates plant products, such as fruits, vegetables, legumes, and whole grains. Due to a lack of carbohydrates, the carnivore diet keeps people in a ketogenic state. In other words, since the diet doesn’t provide sufficient calories from glucose or other sugars, the body resorts to burning fat as a main energy source. This can result in rapid weight loss and short-term improvements in metabolic markers, such as stabilized blood sugar.

People may choose to follow the carnivore diet for a variety of reasons: to lose weight, reduce inflammation, or improve energy levels. However, maintaining this diet long-term is largely considered to be unsustainable, and the short-term benefits are likely to be outweighed by risk of nutritional deficiencies. Although rich in protein, zinc, iron, and vitamin B12, the carnivore diet lacks dietary fiber, essential for digestion, as well as vitamins C, D and E, magnesium, and antioxidants.

Additionally, following a carnivore diet long-term can increase the risk of developing kidney stones, osteoporosis, and, due to animal products being high in saturated fat, even cardiovascular disease. While potentially advantageous in the short term, the carnivore diet is not recommended for long-term sustainable benefits.

Vegan Diet: Plant Power

On the other end of the spectrum lies the vegan diet. Rather than consuming predominantly animal products, a vegan diet is strictly plant-based, emphasizing fruits and vegetables, whole grains, legumes, and nuts while excluding all animal products, including meat, fish, eggs, and honey. 

Many of the downsides of a carnivore diet are not present in a vegan diet. Due to lacking animal products and instead incorporating many carbohydrate-rich foods, the vegan diet is significantly lower in saturated fat and much higher in fiber, minerals and antioxidants that help protect against disease. Additionally, consuming a strict plant-based diet lowers the risk of type 2 diabetes, and lowers blood pressure and cholesterol. However, the diet lacks adequate sources of vitamin B12 and D, iron, omega-3s, and calcium. It is essential to take supplements if adhering to a vegan diet long-term. 

Although many people choose to eat a plant-based diet due to environmental and ethical considerations, others choose it predominantly for health reasons. If the diet is well-planned and accounts for nutritional deficiencies, it can be very healthful and promote sustainable and long-term benefits.

Balance is Key

When considering its nutritional profile and long-term sustainability, the vegan diet comes out on top when compared to the carnivore diet. Rich in fiber, antioxidants, and a variety of vitamins and minerals while also low in saturated fat, a plant-based diet is better suited as a long-term diet. The carnivore diet, despite being rich in protein, iron, and vitamin B12, is best suited as a temporary diet because of the lack of antioxidants and fiber, and increased risk of cardiovascular disease.

Although both diets have benefits and downsides, there is one clear conclusion regarding these two opposing lifestyles: We are omnivores for a reason. Although people have their own personal preferences, balance is the most important factor in a diet, and dedicating yourself to one side of the spectrum has the potential to limit the nutrients and overall benefits the body receives.

The regions of the world where people live the longest are referred to as “Blue Zones.” In these areas, people consume diets rich in fruits, vegetables, legumes, and whole grains, as well as select animal proteins, such as fish and dairy. Also known as the Mediterranean Diet, this diet shows that balance is most important for overall health, and humans operate most optimally by living in accordance with the benefits of both plant and animal-based foods.

References

Carnivore Diet vs. Vegan - ALOHA. (n.d.). Aloha. https://aloha.com/blogs/articles/carnivore-diet-vs-vegan 

Evtushenko, Valeriy (2018, September 28). Raw meat and vegetables [Image]. Unsplash. https://unsplash.com/@valeriycrimea

LeWine, H. E. (n.d.). What is the carnivore diet? Harvard Health. https://www.health.harvard.edu/diet-and-nutrition/what-is-the-carnivore-diet

The Health Implications of Plant-Based vs. Omnivore Diets: A Deep Dive. (2024, May 15). Active Health. https://acthealth.org/the-health-implications-of-plant-based-vs-omnivore-diets-a-deep-dive/

Watson, S. (n.d.). Vegan Diet: Food List, Benefits & Risks. WebMD. https://www.webmd.com/diet/vegan-diet-overview

Assessed and Endorsed by the MedReport Medical Review Board