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Vegan vs Carnivore - Who's right?

Some vegans believe meat causes cancer and destroys the planet. But meat-eaters often argue that giving up animal foods leads to nutritional deficiencies. Both sides say their approach is healthier. What does science say? And how can you best help clients, no matter their dietary preferences? Keep reading for the answers.


Put a group of vegans and Paleo enthusiasts in the same social media thread, and one thing is nearly 99 percent certain: They’ll start arguing about food.

“Meat causes cancer!”

“You need meat for B12!”

“But meat production leads to climate change!”

“Meat-free processed food is just as bad!”

And on it will go.

Let’s just say that, when it comes to the vegan vs. meat-eater debate, people have thoughts, and they feel strongly about them.

Who’s right?

And which approach is right for you?

As it turns out, the answers to those questions are nuanced.

In this article, you’ll find our take on the vegetarian vs. meat-eater debate, which you may find surprising—potentially even shocking—depending on your personal beliefs.

You’ll learn:

  • The real reasons plant-based diets may lower risk for disease.

  • Whether eating red and processed meat raises risk for certain diseases.

  • How to eat for a better planet.

  • Why some vegetarians feel better when they start eating meat—and, conversely, why some meat-eaters feel better when they go vegetarian.

Vegan vs. vegetarian vs. plant-based vs. omnivore: What does it all mean?

Different people use plant-based, vegetarian, vegan, and other terms in different ways. For the purposes of this article, here are the definitions we use at Precision Nutrition.

Plant-based diet: Some define this as “plants only.” But our definition is broader. For us, plant-based diets consist mostly of plants: vegetables, fruits, beans/legumes, whole grains, nuts, and seeds. In other words, if you consume mostly plants with some animal-based protein, Precision Nutrition would still consider you a plant-based eater.

Whole-food plant-based diet: A type of plant-based diet that emphasizes whole, minimally processed foods.

Fully plant-based / plant-only diet: These eating patterns include only foods from the plant/fungi kingdom without any animal products. Fully plant-based eaters don’t consume meat or meat products, dairy, or eggs. Some consume no animal byproducts at all—including honey.

Vegan diet: A type of strict, fully plant-based diet that tends to include broader lifestyle choices such as not wearing fur or leather. Vegans often attempt to avoid actions that bring harm or suffering to animals.

Vegetarian diet: “Vegetarian” is an umbrella term that includes plant-only diets (fully plant-based / plant-only / vegan) as well as several other plant-based eating patterns:

  • Lacto-ovo vegetarians consume dairy and eggs.

  • Pesco-pollo vegetarians eat fish, shellfish, and chicken.

  • Pescatarians eat fish and shellfish.

  • Flexitarians eat mostly plant foods as well as occasional, small servings of meat. A self-described flexitarian seeks to decrease meat consumption without eliminating it entirely.

Omnivore: Someone who consumes a mix of animals and plants.

Now that we know what the terms mean, let’s turn to the controversy at hand.

The Health Benefits of Vegetarian vs. Omnivore Diets

Many people assume that one of the big benefits of plant-only diets is this: They reduce risk for disease.

And a number of studies support this.

For example, when researchers in Belgium asked nearly 1500 vegans, vegetarians, semi-vegetarians, pescatarians, and omnivores about their food intake, they found that fully plant-based eaters scored highest on the Healthy Eating Index, which is a measure of dietary quality.

Omnivores (people who eat at least some meat) scored lowest on the Healthy Eating Index and the other groups scored somewhere in between. Meat eaters were also more likely than other groups to be overweight or obese.

Other research has also linked vegetarian diets with better health indicators, ranging from blood pressure to waist circumference.

So, is the case closed? Should we all stop eating steaks, drinking lattes, and making omelets?

Not necessarily.

That’s because your overall dietary pattern matters a lot more than any one food does.

Eat a diet rich in the following foods and food groups and it likely doesn’t matter all that much whether you include or exclude animal products:

  • minimally-processed whole foods

  • fruits and vegetables

  • protein-rich foods (from plants or animals)

  • whole grains, beans and legumes, and/or starchy tubers (for people who eat starchy carbs)

  • nuts, seeds, avocados, extra virgin olive oil, and other healthy fats (for people who eat added fats)

Of the foods we just mentioned, most people—and we’re talking more than 90 percent—do not consume enough of one category in particular: fruits and vegetables. Fewer than 10 percent of people, according to the Centers for Disease Control, eat 1.5 to 2 cups of fruit and 2 to 3 cups of vegetables a day.

In addition, other research has found that ultra-processed foods (think chips, ice cream, soda pop, etc.) now make up nearly 60% of all calories consumed in the US.

Fully plant-based eaters score higher on the Healthy Eating Index not because they forgo meat, but rather because they eat more minimally-processed whole plant foods such as vegetables, fruits, beans, nuts, and seeds.

Since it takes work—label reading, food prep, menu scrutiny—to follow this eating style, they may also be more conscious of their food intake, which leads to healthier choices. (Plant-based eaters also tend to sleep more and watch less TV, which can also boost health.)

And meat-eaters score lower not because they eat meat, but because of a low intake of whole foods such as fish and seafood, fruit, beans, nuts, and seeds. They also have a higher intake of refined grains and sodium—two words that usually describe highly-processed foods.

Meat-eaters, other research shows, also tend to drink and smoke more than plant-based eaters.

In other words, meat may not be the problem. A diet loaded with highly-processed “foods” and virtually devoid of whole, plant foods, on the other hand, is a problem, regardless of whether the person following that diet eats no meat, a little meat, or a lot of meat.

Now check out the middle of the Venn diagram below. It highlights the foundational elements of a healthful diet that virtually everyone agrees on, no matter what their preferred eating style.

These are the nutritional choices that have the greatest positive impact on your health.

Does meat cause cancer?

For years, we’ve heard that meat-eating raises risk for cancer, especially when it comes to red and processed meat.

And research suggests that red and processed meat can be problematic for some people.

Processed meat—lunch meat, canned meat, and jerky—as well as heavily grilled, charred, or blackened red meat can introduce a host of potentially carcinogenic compounds to our bodies.

Several years ago, after reviewing more than 800 studies, the International Agency for Research on Cancer (IARC), a part of the World Health Organization, determined that each daily 50-gram portion of processed meat—roughly the amount of one hotdog or six slices of cooked bacon—increased risk of colon cancer by 18 percent.

They listed red meat as “probably carcinogenic” and processed red meat as “carcinogenic,” putting it in the same category as smoking and alcohol.

So no more bacon, bologna, salami, or hotdogs, right?

Again, maybe not.

First, we want to be clear: We don’t consider processed meat a health food.

But “eat less” is not the same as “eat never.”

Why? Several reasons.

First, the research is a bit murky.

Several months ago, the Nutritional Recommendations international consortium, made up of 14 researchers in seven countries, published five research reviews based on 61 population studies of more than 4 million participants, along with several randomized trials, to discern the link between red meat consumption and disease.

Cutting back on red meat offered a slim benefit, found the researchers, resulting in 7 fewer deaths per 1000 people for red meat and 8 fewer deaths per 1000 people for processed meat.

Overall, the panel suggested that adults continue their current red meat intake (both processed and unprocessed), since they considered the evidence against both types of meat to be weak, with a low level of certainty.

In their view, for the majority of individuals, the potential health benefits of cutting back on meat probably do not outweigh the tradeoffs, such as:

  • impact on quality of life

  • the burden of modifying cultural and personal meal preparation and eating habits

  • challenging personal values and preferences

Second, the IARC does list processed meat in the same category as cigarettes—because both do contain known carcinogens—but the degree that they increase risk isn’t even close.

To fully explain this point, we want to offer a quick refresher on two statistical terms—“relative risk” and “absolute risk”—that many people tend to confuse.

Relative risk vs. absolute risk: What’s the difference?

In the media, you often hear that eating X or doing Y increases your risk for cancer by 20, 30, even 50 percent or more. Which sounds terrifying, of course.

But the truth? It depends on what kind of risk they’re talking about: relative risk or absolute risk. (Hint: It’s usually relative risk.)

Let’s look at what each term means and how they relate to each other.

Relative risk: The likelihood something (such as cancer) will happen when a new variable (such as red meat) is added to a group, compared to a group of people who don’t add that variable.

As noted earlier, on average, studies have found that every 50 grams of processed red meat eaten daily raises relative risk for colon cancer by about 18 percent.

Like we said, that certainly sounds scary.

But keep reading because it’s not as dire as it seems.

Absolute risk: The amount that something (such as red meat) will raise your total risk of developing a problem (such as cancer) over time.

Your absolute risk for developing colon cancer is about 5 percent over your lifetime. If you consume 50 grams of processed red meat daily, your absolute risk goes up to 6 percent. This is a 1 percent rise in absolute risk. (Going from 5 percent to 6 percent is, you guessed it, an 18 percent relative increase.)

So, back to smoking. Smoking doubles your risk of dying in the next 10 years. Smoking, by the way, also accounts for 30 percent of all cancer deaths, killing more Americans than alcohol, car accidents, suicide, AIDS, homicide, and illegal drugs combined.

That’s a lot more extreme than the 1 percent increase in lifetime risk you’d have by eating a daily hot dog.

Finally, how much red and processed meat raises your risk for disease depends on other lifestyle habits—such as exercise, sleep, and stress—as well as other foods you consume.

Getting plenty of sleep, exercising regularly, not smoking, and eating a diet rich in vegetables, fruits and other whole foods can mitigate your risk.

Is processed meat the best option around? No.

Must you completely part ways with bacon, ham, and franks? No.

If you have no ethical issues with eating animals, there’s no need to ban red and processed meat from your dinner plate. Just avoid displacing other healthy foods with meat. And keep intake moderate.

Think of it as a continuum.

Rather than eating less meat, you might start by eating more fruits and vegetables.

You might go on to swap in whole, minimally-processed foods for ultra-processed ones.

Then you might change the way you cook meat, especially the way you grill.

And then, if you want to keep going, you might look at reducing your intake of processed and red meat.

Okay, but at least plants are better for the planet. Right?

The answer, yet again, is pretty nuanced.

Generally speaking, consuming protein from animals is less efficient than getting it straight from plants. On average, only about 10 percent of what farm animals eat comes back in the form of meat, milk, or eggs.

Unlike plants, animals also produce waste and methane gasses that contribute to climate change. “Raising animals for slaughter requires a lot of resources and creates a lot of waste,” explains Ryan Andrews, MS, MA, RD, CSCS, author of A Guide to Plant-Based Eating and adjunct professor at SUNY Purchase.

For those reasons, a gram of protein from beef produces roughly 7.5 times more carbon than does a gram of protein from plants. Cattle contribute to about 70 percent of all agricultural greenhouse gas emissions, while all plants combined contribute to just 4 percent.

But that doesn’t necessarily mean you must completely give up meat in order to save the planet. (Unless, of course, you want to.)

For a 2019 study in the journal Global Environmental Change, researchers from Johns Hopkins and several other universities looked at the environmental impact of nine eating patterns ranging from fully plant-based to omnivore.

Notably, they found:

  • Reducing meat intake to just one meal a day cuts your environmental impact more than does a lacto-ovo vegetarian diet.

  • An eating pattern that includes small, low on the food chain creatures—think fish, mollusks, insects, and worms—poses a similar environmental impact as does a 100 percent plant-only diet.

In other words, if reducing your environmental impact is important to you, you don’t necessarily need to go fully plant-based to do it.

Isn’t meat the best source of iron—not to mention a lot of other nutrients?

Meat eaters sometimes argue that one of the cons of a vegetarian diet is this: Without meat, it’s harder to consume enough protein and certain minerals.

And there may be some truth to it.

Meat, poultry, and fish come packed with several nutrients we all need for optimal health and well-being, including protein, B vitamins, iron, zinc, and several other minerals.

When compared to meat, plants often contain much lower amounts of those important nutrients. And in the case of minerals like iron and zinc, animal sources are more readily absorbed than plant sources.

Remember that study out of Belgium that found vegans had a healthier overall dietary pattern than meat-eaters? The same study found that many fully plant-based eaters were deficient in calcium.1

Compared to other groups, fully plant-based eaters also took in the lowest amounts of protein.

Plus, they ran a higher risk of other nutrient deficiencies, such as vitamin B12, vitamin D, iodine, iron, zinc, and omega-3 fats (specifically EPA and DHA).

Is this proof that everyone should eat at least some meat?

Not really. It just means that fully plant-based eaters must work harder to include those nutrients in their diets (or take a supplement in the case of B12).

This is true for any diet of exclusion, by the way. The more foods someone excludes, the harder they have to work to include all of the nutrients they need for good health.

Bottom line: Any eating pattern can be healthy or unhealthy.

Someone can technically follow a fully-plant based diet without eating any actual whole plants.

For example, all of the following highly refined foods are meat-free: snack chips, fries, sweets, sugary breakfast cereals, toaster pastries, soft drinks, and so on. And meat-eaters might also include similar foods.

Vegetarian and carnivore diets only indicate what people eliminate—and not what people include.

Whether someone is on the carnivore diet, the keto diet, the Mediterranean diet, or a fully plant-based diet, the pillars of good health remain the same.

If you have strong feelings about certain eating patterns (for example, maybe you’re an evangelical vegetarian or Paleo follower), try to put those feelings aside so you can zero in on your client’s values and needs—rather than an eating pattern they think they “should” follow.

What you might find is that most clients truly don’t care about extreme eating measures like giving up meat or giving up carbs. They just want to get healthier, leaner, and fitter—and they don’t care what eating pattern gets them there.

How do we know this?


Each month, roughly 70,000 people use our free nutrition calculator. They tell us what kind of an eating pattern they want to follow, and our calculator then provides them with an eating plan—with hand portions and macros—that matches their preferred eating style. We give options for just about everything, including plant-based eating and keto.

What eating pattern do most people pick?

The “eat anything” pattern. In fact, a full two-thirds of users choose this option, with the remaining third spread across the other five options.

In other words, they don’t particularly care what they eat as long as it helps them reach their goals. Interestingly, of the many options we list, people choose fully plant-based and keto diets the least.

In Conclusion, there is no "right way" to do this. A lot of this comes down to personal preference.


No matter what your preference(s) are, we can help! We have experience with vegetarian diets, keto, etc. We can customize any meal plan to your preference.

Ready to get started with your custom meal plan? Send an email to:


This article was modified form a full article that was posted by Precision Nutrition. You can check out the full article here:

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