Two Popular Dietary Theories: Plant-Based vs. Carnivore Style Diets

whitney starrs
Jan 18
9 min read

Diet choices have become a hot topic everywhere you look and listen today.

Especially at the beginning of each New Year. Insert eye roll ;)

Information overload is coming at us 24/7, full force.

If you follow any sort of health or wellness accounts, on any platform, I am sure you have seen the fairly new, popular Carnivore Diet pop up.

At this point, most are familiar with one form of Plant Based (plant forward) or another- be it vegan, vegetarian which includes some dairy like eggs and cheese, and even pescetarian which includes fish but relies mainly on plant based sources.

These two debated dietary theories both have pros & cons, but is one really better than the other?

Plant based diets and the carnivore diets, both stand out for their stark differences and passionate followers.

Supporters of each diet promote various health claims, ethical considerations, and personal experiences.

Let's break down the details of these two dietary theories, exploring their health benefits, challenges, and philosophies.

Understanding the Plant-Based Diet

A plant-based diet focuses on foods derived from plants, such as vegetables, fruits, whole grains, legumes, nuts, and seeds. While some associate this diet strictly with veganism, it can also include a moderate intake of animal products, emphasizing plant foods- like vegetarianism or pescetarian.

Key Health Benefits of a Plant-Based Diet

Nutrient Density: Plant-based diets are packed with vital nutrients. For example, a cup of spinach has 181% of the daily requirement for Vitamin K. Foods like beans and lentils are not only rich in protein but also provide significant fiber, which is essential for digestive health. PMID: 36834032
Heart Health & Disease Prevention: Vegetarian & Vegan diets can lower the risk of type 2 diabetes, hypertension and high cholesterol. Studies show that people who follow a plant-based lifestyle can reduce their risk of heart disease by 32%, and type 2 diabetes by 50%. This is because a plant forward diet is typically lower in saturated fats and results better blood pressure regulation and insulin resistance. PMID: 15297079 PMID: 36834032 PMC7551487.
Weight Management: Research indicates that individuals on plant-based diets can lose weight effectively—those who follow such diets tend to eat fewer calories but still feel full, thanks to the high fiber content.
Gut health & Nutrient Absorption: Plant forward diets foster the growth of good gut flora, which aids in stronger gut health/ less inflammation. Having a healthy intestinal tract and gut lead to better absorption of nutrients. Every heard of "leaky gut"? That's another day... PMID: 34836399
Sustainability: Choosing plant-based foods contributes to lower greenhouse gas emissions, and a smaller carbon footprint. Reports indicate that shifting towards a plant-based diet could cut food-related carbon emissions by up to 70%. PMID: 34836399

Potential Challenges of a Plant-Based Diet

Despite its many benefits, a plant-based diet can come with some challenges:

Nutritional Deficiencies: Key nutrients like Vitamin B12, iron, zinc, calcium, and omega-3 fatty acids can be hard to find in a strictly plant-based diet. Planning meals carefully can help prevent deficiencies. Supplementation can also be recommended to accompany dietary choices to avoid deficiencies. PMID: 34836399
Social Situations: Eating out or attending gatherings can be tricky if few plant-based options are available. This can sometimes lead to feelings of isolation among plant-based dieters. Doing some research ahead of time, or working with a nutrition professional is a good way to overcome this obstacle.
Initial Adjustments: For people used to a traditional diet, making the switch can be challenging. Cravings for meat or dairy may occur, necessitating support during the transition. Again, working with a professional can help you navigate a dietary shift.

Unpacking the Carnivore Diet

In contrast, the carnivore diet consists solely of animal products like meat, fish, eggs, and some high-fat dairy. Some that follow this may eliminate dairy all together as well. On a Carnivore diet all plant-based foods are off the table. No fruits, veggies, nuts, beans, or seeds.

Key Health Benefits of a Carnivore Diet

Simplicity: Some individuals appreciate

the straightforward nature of the carnivore diet. With fewer choices, meal planning becomes easier. Many can feel overwhelmed in planning and preparing their meal choices for the week. A daily breakfast of steak and two eggs is pretty straightforward. Zero calorie counting. Very simple.
Less Inflammation: Some followers of the carnivore diet report reduced inflammatory symptoms. Eliminating certain plant foods might help alleviate issues with joint pain, auto-immune disease, and even digestive discomfort for those that have trouble with certain plants and veggies. PMID: 34934897 PMID: 27759811

The lowering of inflammation from the Carnivore diet is typically due to the avoidance of all other foods that had been previously contributing to the inflammation; not the factor of only consuming meat.
High Protein Intake: With a significant focus on meat, the protein levels in this diet can support muscle growth. For example, 100 grams of beef can provide around 26 grams of protein. Many find that an increase in protein and a low or no carb diet will aid in weight loss. PMID: 32833688
Potential Weight Loss: People often find that the satiety from high protein and fat helps them manage their weight more effectively. Some have reported losing an average of 10% of their body weight after a few months, resulting in a lower BMI. PMID: 34934897 PMID: 36033148
Mental Clarity: Supporters claim that avoiding carbs leads to fewer blood sugar spikes, contributing to improved focus and mental clarity. It should be noted that there is not a lot of scientific research on this diet, it's claims are primarily anecdotal.

Potential Challenges of a Carnivore Diet

However, the carnivore diet also has many notable downsides:

Nutritional Concerns: This diet lacks fiber and many essential vitamins and minerals that come only from plants. Over time, this may lead to vitamin and nutrient deficiencies, like a noted lack of Vitamin C which is crucial for immune function. Osteoporosis and Gout are also two concerns with the Carnivore diet. Inflammation can also increase for some, every body is different. PMID: 32833688

Risk of Chronic Diseases: High saturated fat intake raises concerns about heart health. Research suggests that long-term adherence may increase the risk of developing heart-related issues.

Kidney disease & Non- Alcoholic Fatty Liver Disease are also linked to diets with high saturated fat/ increase in LDL cholesterol.

Increased risk of cancer has been reported with those who consume a lack of fiber, with Carnivore diet followers consume zero. PMID: 31805451 PMID: 37571305

Digestive Issues: At the beginning of this diet, many report cases of constipation followed by weeks of extreme diarrhea.

Without fiber, some individuals report constipation or other gastrointestinal issues, which can lead to discomfort. Over time these issues could lead to other gastrointestinal issues like bowel obstruction.

While kidney stones are not a digestive issue- (excretory system), consistent diarrhea and the fat not being properly absorbed in the intestines can lead to it binding to oxalate (a natural molecule found in humans & plants like spinach, almonds, baked potato with skin), causing higher levels of oxalate in the urine, which then turns into kidney stones.
Sustainability/ Limited Food Choices: Eating out becomes challenging, as options are severely restricted. This may cause social anxiety or frustrations during group meals. The sustainability of this diet is also difficult for some for two reasons- budget and lack of diversity of meal options. The environmental impact of this diet should be taken into account as well in a larger picture.
Sports Performance: Sports performance may be affected; sports performance outcomes typically improve with carbohydrates, where those practicing a Carnivore diet would be at a disadvantage. PMID: 35150294. PMID: 33599941.

Blood Glucose: While some have reported lower blood glucose levels; over time these would likely increase- the body has plenty of room to store fat and carbs. The body does not have room to store excess protein, so when it recognizes it's "limit" it will start turning that protein into excess glucose.

Comparing and Contrasting the Two Diets

These diets reflect different philosophies and health outcomes.

Nutritional Composition: A plant-based diet is rich in a variety of nutrients and fiber, while a carnivore diet delivers high protein and fat but may lack vital nutrients.
Ethics and Sustainability: Advocates of plant-based diets often highlight animal welfare and reducing environmental impact. In contrast, supporters of the carnivore diet view animal consumption as a natural part of our diet. The realistic idea that one can consume only one food group for an extended period of time is also hard for most to sustain.
Flexibility: The plant-based diet's adaptability appeals to more people. The strictness of the carnivore diet may benefit those desiring a straightforward plan. Those that have history of or may be prone to disordered eating should be mindful of this dietary theory.
Long-term Health: More research is needed to understand the long-term impacts of each diet. Attention should be given to potential deficiencies and risks associated with both diets. The most significant "study" of the Carnivore diet is an online 2021 "Harvard" Study, pulled from various social media platforms, and is based on questionnaires and anecdotal evidence.

Making the Right Choice

The decision between a plant-based diet and a carnivore diet hinges on personal health needs, lifestyle preferences, and ethical considerations.

Each diet offers unique advantages and challenges.

Every body and everybody is different. The is no one correct way of eating for anyone.

However; as a nutrition professional, while I can acknowledge some of the benefits of the carnivore diet, I cannot say that I would ever recommend this to anyone. The lack of scientific research, and potential health risks outweigh the benefits in my opinion. I feel similar about the ketogenic which includes carbs but the majority of those that follow it exclude them, as well as choose poor or processed choices of protein and fats.

Any diet that eliminates whole food groups (unless for medical/ allergic reasons) should be avoided. Your body requires all three macronutrients, not just one. If there are fruits or veggies you don't like, don't eat them!

Focus on fibrous produce that you love. Fill your plates and bowls with colors & carbs, and make sure you're getting your protein, whether it be meat or plant based in there too!

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