Is Meat Bad for You? The Complete Scientific Answer

Meat has become more and more controversial of late. 

Some say its damaging effects are on par with smoking, and others even claim we should apply a special “health tax” on meat eaters. 

The contrarians say meat has a number of positive health benefits, very few downsides, and most of the research showing otherwise is on low-quality processed meats.

And others take a middle-of-the-road outlook and say meat might cause some health problems in large amounts, but it’s healthy in moderation. 

Looking at the scientific evidence only further muddies the waters.

If you look online, you’ll find some studies that seem to show meat is bad for you, some studies that show it’s benign, and others that seem to show it’s good for you. 

In the past few years, though, the pendulum of public opinion has swung hard in the “meat is bad for you” direction, largely thanks to several position statements from major health authorities. 

Who’s right? 

Well, the short answer is meat probably isn’t as bad for you as many news outlets claim, and reducing your intake of meat probably won’t make a big difference in your health. 

That said, it’s also fair to say eating as much processed or fatty meat as you want probably isn’t good for you, either.

Ready for the long answer? 

Let’s kick things off by looking at exactly what meat is, then we’ll get into the case for and against eating it.

Table of Contents

• What Is Meat?
• The Case for Eating Meat
• What Happens to Your Body When You Stop Eating Meat?
• It's more difficult to get enough protein for building muscle.
• It’s not more effective for losing weight than an omnivorous diet.
• It increases the risk of nutrient deficiencies. 
• It doesn’t protect you from heart disease.
• The Case Against Eating Meat
• How Much Meat Can You Safely Eat?
• The Bottom Line on Eating Meat

What Is Meat?

Meat refers to the flesh of any animal commonly consumed by humans.

This includes beef, chicken, lamb, pork, and seafood such as salmon, scallops, and shrimp.

When many people in the U.S. say meat, though, they’re specifically referring to red meat, which comes from land animals such as beef and lamb as well as wild game such as elk, deer, and boar.

White meat refers to, well, meat that’s white, which typically comes from animals like chicken, turkey, and pork, although some people consider pork a red meat.

Technically, though, the term meat refers to animal flesh from any animal, whether it lives in water, on land, or in the air. 

Meat that’s been processed by smoking, salting, or curing, or treated with other chemicals to enhance the flavor, texture, or shelf life is referred to as processed meat. Typically, it’s also red meat.

Sausage, bacon, deli meats, and jerky are all examples of processed meats.

Last but not least, offal, also called variety meats, pluck, or organ meats, are the internal organs of a particular animal. 

Liver and liver pâtés are among the most popular of these meats in the West. But the truth is people all over the world eat everything from cattle’s brain curry in Indonesia to rooster testicle stew in Hungary.

Typically, though, when people are debating about whether or not you should eat meat, they’re talking about beef.

Summary: Meat refers to the flesh of any animal consumed by humans. Red meat refers to meat from land mammals such as beef, bison, and deer, whereas white meat refers to meat from animals such as chicken, turkey, and pork, and processed meat refers to meat that’s been salted, cured, or treated with other chemicals to improve the flavor, texture, or shelf life. 

The Case for Eating Meat

In November 2019, a group of 14 researchers led by Dalhousie University epidemiologist Bradley Johnston published five systematic reviews that concluded there are no good health reasons for people to reduce their consumption of red and processed meat.

The studies were published in the journal Annals of Internal Medicine, and their findings summarized in a new clinical guideline by the Nutritional Recommendations (NutriRECS) Consortium.

As you can imagine, these studies sparked a strong backlash from the anti-meat crowd.

They also seem to fly in the face of most of the official recommendations from health and nutrition organizations.

For example, in 2015, the World Health Organization’s International Agency for Research on Cancer announced it had classified processed meat as carcinogenic to humans, and red meat as probably carcinogenic to humans.

Moreover, the American Heart Association, the US government’s dietary guidelines panel, the American Cancer Society, and the World Cancer Research Fund, have long recommended that people limit their consumption of red and processed meat.

So, why the contradictory findings of this new series of systematic reviews?

Well, the scientists took a different approach to most of the previous research looking at this question. Instead of examining at every study on the topic, including many with dubious methodologies and potentially biased results, they limited their research to cohort studies and randomized controlled trials. 

These two types of studies are regarded as the “gold standard” of scientific research, and are thus most likely to help us get at the truth. 

The researchers intentionally didn’t include evidence from other, less reliable studies such as observational, case-control, or animal studies.

When sorting through the studies they did include in their reviews, they also applied a rigorous standard for deciding how to weight the evidence known as the Grading of Recommendations Assessment, Development, and Evaluation (GRADE). This is a widely used system for deciding how much credibility they should give each study when making broad recommendations.

While these reviews aren’t the final word on the health effects of meat, they are strong evidence the claims against eating might may have been overblown. They certainly support the idea that consuming meat in moderation is fine. 

It’s also worth considering the many health benefits of eating meat, such as: 

• Appetite suppression and metabolic boost. 

Meat is a much better source of protein than plant foods, which helps decrease appetite and increase calorie burning thanks to an increase in the thermic effect of food. 

• Fat loss and muscle building.

Meat’s high-protein content also means it’ll help support fat loss and muscle buliding, especially when combined with a strength-training program.

• Improved bone density and health.

Contrary to what many people believe, eating more animal protein seems to improve bone health, not hurt it. For example, research shows older women who consume the highest amounts of animal protein have a 69% decreased risk of hip fractures.

• Increased iron intake and lower risk of anemia. 

Meat is the best source of highly absorbable heme iron, which is easier to absorb than non-heme iron found in plants.

One more line of evidence in favor of meat consumption are the many studies showing negative health effects when you completely remove meat from the diet, which you’ll learn about in the next section.

Summary: The highest quality scientific evidence available shows you probably won’t benefit from reducing your intake of red meat, and research also shows many benefits of regular meat consumption.

What Happens to Your Body When You Stop Eating Meat?

In other words, what happens when you follow a vegan diet? 

Well, several things, and most of them aren’t good. 

The main problems you’ll run into following a vegan diet are: 

• It’s more difficult to get enough protein for building muscle.
• It’s not more effective for losing weight than an omnivorous diet.
• It increases the risk of nutrient deficiencies. 
• It doesn’t protect you from heart disease.

It’s more difficult to get enough protein for building muscle.

All things considered, animal proteins are better for building muscle than plant proteins. 

The reason for this is because animal proteins are higher in essential amino acids, especially leucine, and are more easily digested and absorbed than plant proteins. All of these factors make animal protein more effective for promoting muscle growth.

For a more detailed explanation on animal vs. plant protein, check out this article:

Animal Protein vs. Plant Protein: Which Is Best for Building  Muscle?

While this doesn’t mean vegans can’t get enough protein to maximize muscle gain, it does take a bit more work, especially in the meal-planning department.

If you’d like to learn more about how you can plan vegan meals to get enough protein to build muscle as efficiently as possible, check out this article: 

This Is the Definitive Guide to Vegan Bodybuilding Every Plant Eater Needs 

It’s not more effective for losing weight than an omnivorous diet.

Many vegans claim giving up all animal foods will help you lose weight, and this is true. 

Veganism can help you lose weight.

What many vegans fail to mention, though, is that many studies show you can lose weight just as effectively while eating meat.

The vegan diet helps you lose weight the same way any diet helps you lose weight: by forcing you to eat fewer calories. 

This is true of the Military Diet, the Mediterranean diet, and the carnivore diet—the vegan diet’s polar opposite.  

(Oh, and if you’d like to know if any of these diets are right for your circumstances and goals, then take the Legion Diet Quiz! In less than a minute, you’ll know exactly what diet is right for you. Click here to check it out.)

So, if your primary motivation for giving up meat is to lose weight, you’re barking up the wrong tree.

What’s more, although veganism can help you lose weight, it’s suboptimal for losing fat.

As you learned a moment ago, it’s more difficult for vegans to eat enough protein to gain muscle or maintain muscle while losing fat. This is why many people who lose weight on a low-protein, vegan diet often wind up looking skinny fat instead of slim and muscular after losing weight.

It increases the risk of nutrient deficiencies. 

While vegan diets are rich in many important nutrients, they’re not so rich in other, also very important ones, especially those found in animal foods.

As the American Journal of Clinical Nutrition points out, “vegan diets are usually high in dietary fiber, magnesium, folic acid, vitamins C and E, and phytochemicals and they tend to be lower in calories, saturated fat, and cholesterol, omega-3 fatty acids, vitamin D, calcium, zinc and vitamin B12.”

Vitamin B12 deficiency deserves special attention, as it’s one of the most common, detrimental, and easily-avoided nutrient deficiencies in vegans. 

For example, a study conducted by scientists at the University of Oxford measured B12 levels in 689 men, including 226 omnivores, 231 vegetarians, and 232 vegans. 

They found 52% of the vegans were deficient in B12, compared to just 7% of the vegetarians and only one omnivore (.04%).

The bottom line is veganism significantly increases your risk of becoming deficient in key nutrients. Although you can prevent these problems by consuming certain foods and supplements to make sure you cover your nutritional bases, many vegans don’t do this.

It doesn’t protect you from heart disease.

Lots of people look at veganism as a way to protect their heart health. And there’s some evidence to suggest it can help in this regard.

For example, a study conducted by scientists at the Catholic University at São Paulo has shown that a vegan diet is associated with lower levels of triglycerides, low density lipoproteins, and cholesterol than an omnivorous diet.

The study also found that while there was no difference in high density lipoprotein (HDL) levels, the ratio of HDL to cholesterol was much higher in vegans.

Also, there’s solid research showing that vegetarians—who also don’t eat meat—might have as much as 12% lower risk of death than meat eaters, as well as lower risk of suffering from metabolic syndrome. 

However, veganism also creates a number of problems related to heart health.

Perhaps the most important of these problems is that vegans are at a higher risk of developing omega-3 fatty acid deficiencies. 

Also known as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), omega-3 fatty acids aren’t only beneficial for preventing heart disease, stroke, and type 2 diabetes, but also for:

• Decreasing systemic inflammation
• Improving mood, cognitive performance, and brain health
• Helping prevent weight gain
• Optimizing fat loss
• Accelerating muscle growth

The reason is that vegetable oils don’t contain omega-3 fatty acids, but instead contain a fatty acid called alpha-linolenic acid (ALA), which the body then converts into EPA and DHA.

However, the conversion process is very inefficient in vegans, so it’s hard to obtain them in sufficient amounts without eating animal foods.

Actually, it’s also hard to obtain enough EPA and DHA from animal products because they’re found in much lower levels in meat and eggs than fish.

That’s why both vegans and non-vegans alike should consider taking a fish-oil supplement.

Other research shows vegetarians have higher levels of homocysteine in the blood than omnivores, which is a marker for an increased risk of heart disease.

Despite what many vegans claim, there’s little evidence giving up animal products completely is an effective way to avoid heart disease. In fact, there’s strong evidence eating some animal products may be good for heart health by providing omega-3 fatty acids.

The Case Against Eating Meat

The main reasons people say you shouldn’t eat meat are that it can cause cancer and heart disease.

And vegans can point to a handful of papers that seem to support this position.

For example, a paper published in the 2015 World Health Organization’s International Agency for Research on Cancer announced it had classified processed meat as carcinogenic to humans, and red meat as probably carcinogenic to humans.

More specifically, the paper found that people who eat more red and processed meat were more likely to develop colorectal cancer. The paper also found an association between red meat consumption and prostate cancer, and between the consumption of processed meat and stomach cancer.

Other research indicates that higher red meat consumption can increase the risk of breast cancer, and that eating more red and processed meat increases the overall risk of death.

However, there’s also abundant research that contradicts these claims.

So, where does that leave us? Well, one answer comes from the recently published NutriRECS reviews conducted by researchers from Dalhousie University, who concluded there are no good health reasons for people to reduce their consumption of red and processed meat. 

While some have interpreted this conclusion to mean you can eat as much red or processed meat as you’d like without any negative health complications, their actual recommendations were more moderate.

Let’s take a close look at the author’s wording of their conclusions. 

When it comes to unprocessed red meat, the researchers recommended . . . 

For adults 18 years of age or older, we suggest continuing current unprocessed red meat consumption (weak recommendation, low-certainty evidence).

And when it comes to processed red meat, the researchers recommended . . . 

For adults 18 years of age or older, we suggest continuing current processed meat consumption (weak recommendation, low-certainty evidence).

The reason the researchers qualified their conclusions with “weak recommendation, low-certainty of evidence,” is they felt the studies they reviewed didn’t produce clear enough results to justify a definitive, clear-cut answer.

That said, it’s still the best evidence currently available, so it can’t be easily dismissed.

When you look at all of the current scientific evidence on red and processed meat and your health, the truth of the matter is we don’t really know what the long-term health effects are.

Eating a lot might be bad, not eating any is also probably bad, and it’s unclear what a healthy compromise looks like according to the scientific literature. 

So, where does that leave us? 

Well, there’s little evidence that eating red meat is bad for you, even in relatively large amounts. 

And in the case of processed meats, I’ll quote Mike’s position from a previous article: 

The research shows that it’s reasonable to assume that eating too much processed meat can cause cancer but without controlled interventions, which would never pass an ethics board due to the possibility of actually giving someone cancer, we can’t say for sure.

I’m not afraid to have a hot dog or some deli meat now and then but I eat very little of these types of foods and recommend you do the same.

And here’s Mike again on the closely-related issue of saturated fat:

The long-held belief that saturated fat increases the risk of heart disease has been challenged by recent research, which has been a boon to the fad diet industry, not to mention the meat and dairy industries (we’ve seen a veritable renaissance of meat and dairy consumption).

The problem, however, is that the research used to promote this movement has also been severely criticized by prominent nutrition and cardiology researchers for various flaws and omissions.

These scientists maintain that there is a strong association between high intake of saturated fatty acids and heart disease and that we should follow the generally accepted dietary guidelines for saturated fat intake (less than 10% of daily calories) until we know more.

One more line of evidence against reckless meat consumption can be found by examining a new diet fad known as the carnivore diet, about which Mike wrote an extensive article:

Should You Try the Carnivore Diet? What 74 Studies Say

There are a few major takeaways from that article: 

1. You can probably eat large amounts of red meat—even fatty meat—and still be healthy.
2. You should still eat large amounts of fruits and vegetables, and omitting these in favor of more meat is foolish and unhealthy.
3. You probably shouldn’t eat large amounts of processed meats if you care about your long-term health.

If you want to learn more, read the article.

Summary: Although some studies have shown eating large amounts of red and especially processed meats can increase the risk of heart disease and cancer, the latest and highest quality scientific evidence shows this probably isn’t the case. The safest course of action is to eat meat in moderation. 

How Much Meat Can You Safely Eat?

If you want to keep eating meat, but you also want to optimize your health, longevity, and well-being, what is a sensible omnivore like yourself to do? 

Should you limit yourself to petite portions of red meat only a few times a week, or can you safely indulge in larger amounts of red meat every day?

Well, the scientific evidence doesn’t provide us with any clear answers, but it does give us a few hints at what might be the healthiest strategy.

The 2015 to 2020 Dietary Guidelines for Americans recommend one serving (85 grams) of cooked red and processed meats per week, which is an extremely small amount. That’s one medium-size hamburger patty per week.

These guidelines also stem from largely discredited research that seemed to show eating red meat contributed to cancer and heart disease, so take them with a grain of salt. 

On the other hand, the UK’s National Health Service (NHS) and the World Cancer Research Fund recommend an upper limit of 500 grams of cooked red and processed meat per week, nearly six times more than the Dietary Guidelines for Americans. 

This might sound like a lot of red meat, but it’s really not. In fact, it’s the equivalent of two, eight ounce steaks or one large hamburger and a few pieces of pot roast per week.

This recommendation is also closer to what Americans actually consume: 471 grams of red and processed meat per week.

Now, before you blindly adhere to these guidelines, it’s worth keeping a few facts in mind. 

For one thing, all of these agencies have lumped together red and processed meats, despite the fact that most research shows processed meats pose a significantly greater risk to human health than unprocessed red meat.

Second, these agencies are also assuming that much of the red and processed meat people are eating is high in fat and saturated fat in particular. Thus, their recommendations are also intended to help reduce saturated fat intake. 

If you’re mostly eating leaner cuts of meat and little to no processed meat, though, and not consuming that much saturated fat, then these recommendations might be unnecessarily low.

Finally, these recommendations are also based on studies that generally involve sedentary people, many of whom are following a standard Western diet of processed foods. In other words, people living relatively unhealthy lifestyles. 

We don’t have as much data on how healthy or unhealthy it is for active people eating lots of fresh fruits and vegetables to also eat red or processed meat.

All of these wrinkles open the door to several more questions, such as . . .

Can you eat more than the upper limit of red meat (500 grams per week) if all or most of the red meat you eat is unprocessed?

Can you eat more meat than the upper limit if most of the meat you eat is relatively lean and low in saturated fat? 

Can you eat more meat than the upper limit if you also eat plenty of fresh fruits and vegetables, work out regularly, get plenty of sleep, and otherwise live a healthy lifestyle?

The scientific research doesn’t provide any definitive answers, but common sense would indicate the answers are “yes,” “yes,” and “yes.”

All in all, here’s what we can say: 

1. There is no clear upper or lower limit for how much meat you should eat, although it’s probably a good idea to eat a wide variety of different kinds of meat (fish, poultry, pork, etc.) instead of just red meat.
2. It’s probably best to prioritize lean cuts of red meat over fatty cuts, and to keep your total saturated fat intake below 10% of your total calories.
3. It’s probably best to minimize your intake of processed meats and focus on eating fresh, minimally processed meat instead.
4. Regardless of how much meat you eat, you should also be sure to eat plenty of fresh fruits, vegetables, and whole grains. 

Summary: There is no definitive scientific answer on how much red or processed meat you can eat per week, but it’s probably best to minimize your intake of processed meats and focus on relatively lean cuts of fresh, minimally processed meats from a variety of animals.

The Bottom Line on Eating Meat

Try to find a clear answer on how much and what kind of meat you should eat to stay healthy, and you’ll quickly find yourself in a whirlwind of different ways of thinking.

Some people say eating any meat is bad for you, and several prominent health agencies have echoed these views by saying red meat is a carcinogen. 

Others claim regular red meat is perfectly healthy to eat in any amount, but that processed meat is the real culprit. 

And others claim eating small amounts of meat is fine, but large amounts are bad for you.

By meat, most people mean red meat such as beef or lamb, and by processed meat, most people mean meats that have been salted, cured, or treated with chemicals to improve the flavor, texture, and shelf life. 

The argument in favor of eating meat goes like this:

The highest quality research available shows eating meat isn’t unhealthy, and there’s little benefit in reducing your meat consumption. 

Moreover, meat is also a good source of protein and essential nutrients that are difficult to obtain on vegetarian and vegan diets. 

The argument against eating meat relies on evidence that shows an association between red and processed meat in particular and cancer and heart disease. 

It’s worth noting, though, that much of this research is based on relatively low-quality studies involving sedentary, often overweight people following a standard Western diet of processed foods. 

Thus, it’s hard to say how eating red or processed meats would affect active, lean, healthy people who are also eating lots of fresh fruits, vegetables, and whole grains. 

Where does that leave us? 

While there are no definitive answers, here are some simple, evidence-based recommendations for sensible meat consumption: 

1. There is no clear upper or lower limit for how much meat you should eat, although it’s probably a good idea to eat a wide variety of different kinds of meat (fish, poultry, pork, etc.) instead of just red meat.
2. It’s probably best to prioritize lean cuts of red meat over fatty cuts, and to keep your total saturated fat intake below 10% of your total calories.
3. It’s probably best to minimize your intake of processed meats and focus on eating fresh, minimally processed meat instead.
4. Regardless of how much meat you eat, you should also be sure to eat plenty of fresh fruits, vegetables, and whole grains. 

Do all that, and make sure you stay active, maintain a healthy body fat percentage, and practice a generally healthy lifestyle, and you probably don’t need to worry too much about your meat consumption.

What’s your take on red meat? Have anything else to share? Let me know in the comments below!