An Objective Look At Red Meat, Health and Cancer

Red meat has been strongly demonized in society.

It has long been associated with an unhealthy diet, especially with the current emphasis on avoiding fat in all of its forms.

But, the real question is, is red meat bad for you?

Modern research and news stories have done nothing at all to make red meat look any better.

In fact, the World Health Organization (WHO) has recently concluded that processed meat is a carcinogen while red meat is a probable carcinogen (1,2).

That term, carcinogen, means cancer-causing agent. So, anything said to be a carcinogen can cause cancer – at least in theory.

This conclusion has sent shock waves  throughout the media, especially as bacon and sausages are both considered processed meat under WHO’s definition (3).

To make matters worse, the report suggests that consuming 50 grams of processed meat each day results in an 18% increase in the risk of colorectal cancer (4).

That’s not actually a whole lot of processed meat – roughly two slices of bacon. While many of us probably aren’t consuming processed meat every day, I imagine a decent proportion of the population are.

So, is this the end of the road for red meat?

Should we dramatically reduce our consumption?

There is no simple answer to the question, because the science is actually a great deal more complicated than it first seems.

Carcinogens and Classifications

So, under the WHO’s conclusions, processed meat and red meat have been defined differently. For processed meat, the conclusion looks like this:

For red meat in general, the conclusion looks like this:

In both cases, the classifications are based on the amount of scientific evidence, not on the strength of the observed effect. That’s an important distinction. This means that even though processed meat has been placed in the same category as tobacco, the level of cancer risk is not the same.

As you can see, in the case of red meat, the classification isn’t as strong.

In fact, there is limited evidence that red meat causes cancer, despite the theoretical perspectives that suggest it could.

This all brings us back to the question, is red meat bad for you?

One of the issues here is the idea of cancer-causing agents in general.

The headlines on the topic entirely ignore the actual probabilities involved, so everyone panics.

But, if you really look at it, the numbers aren’t that alarming. For example, out of 100,000 people who smoke regularly, around 1,000 of those will get lung cancer as a result. So, that’s roughly 1%.

In contrast, for 100,000 people who eat bacon regularly, maybe 120 will end up with cancer (5).

Cancer is complicated. There are many different factors that play a role in cancer development, including many that we don’t know and others that we can’t control. So yes, you could cut out processed meat and even red meat, and you might be a little bit safer.

But for the most part, the size of the effect means that cutting out processed meat would have a trivial impact.

A similar outcome is probably true for red meat, if red meat even does cause cancer. After all, research hasn’t even proven that much yet.

One of the reasons that a connection hasn’t been proven with red meat is that many of the studies have been observational in nature. Additionally, studies that have found an effect have often found one that is small in magnitude.

For example, one meta-analysis on the topic found that there were many inconsistencies across studies and that other factors (like lifestyle) probably influenced some of the observed results (6).

Another study suggested that there simply is not enough evidence to determine whether or not red meat plays a role in cancer development (7).

It’s also important to note that WHO never suggested that people stop eating red meat or processed meat. Instead, the recommendation is that for people to lower their consumption if they are eating high amounts of red meat and processed meat (8).

In fact, WHO even noted that red meat is associated with health benefits, so cutting it out entirely is certainly not advisable (9).

The Health Implications of Red Meat

So, cancer aside, is red meat bad for you?

To really understand this, we need to look beyond all of the emotions and controversies that surround red meat.

There has been a considerable amount of research into red meat over the years, and in theory, that should give us considerable insight into the impact that red meat does have on the body.

However, it is important to note that there have also been some serious limitations in this research.

One major issue comes from the observational study approach.

Observational studies are powerful because they let researchers see trends across an entire population or a very large sample size. But, because of this, observational studies only see patterns, they can’t actually work out cause and effect.

As much as possible, researchers try to take into account factors that might bias their outcomes, but it is never possible to do this completely.

One reason for this is that red meat is already viewed as unhealthy. So, in general, people who are less healthy or who care about their health less will tend to eat more red meat. There are many exceptions to this of course, but it is accurate in many cases.

This relationship means that any study would see associations between red meat consumption and negative health outcomes, even though many of those associations were probably caused by lifestyle, not by red meat itself.

That pattern is one reason why there is limited information about what impact red meat actually has on cancer risk or on other health issues.

Red Meat, Fat and Cholesterol

A key area of debate about red meat is tied into the topic of fat and cholesterol. For a long time, our population has focused on reducing the amount of fat and cholesterol in our diet, in an effort to reduce the prevalence of heart disease.

I talk about the relationship between cholesterol and heart disease in much more depth in my post on the cholesterol controversy, but in general, the link between cholesterol, fat and heart disease isn’t as strong as people often believe.

In fact, high fat diets may be as healthy or healthier than the more common high-carb, low-fat diet.

For example, experimental studies comparing low-fat to low-carb diets tend to find that a diet low in carbs but higher in fat is associated with better health outcomes rather than the other way around (10,11).

This is an important indication that fat isn’t actually as bad for health as we are told, and may actually be related to significant health benefits.

Research has even indicated that there isn’t significant evidence to support the relationship between saturated fat and cholesterol (12).

So, avoiding red meat because of its fat content may be a misguided concept.

Nutrition

Another thing to consider with red meat is the nutrients that it contains.

For example, a 3 oz serving of fat trimmed porterhouse steak contains the following nutrients (13):

• Niacin (18% DV)
• Vitamin B6 (16% DV)
• Vitamin B12 (31% DV)
• Zinc (26% DV)
• Selenium (24% DV)

This is actually a small selection of the nutrients in beef, and there are many more as well.

The presence of nutrients is important because they strongly contribute to health overall and an adequate nutrient intake is something that many people do not have.

Of all the vitamins in red meat, one of the most significant ones is vitamin B12, because you can’t get vitamin B12 from plants.

The zinc in red meat is also important. That zinc is highly bioavailable and has the ability to increase how zinc is used from other sources as well (14).

Zinc itself is also a significant mineral and it plays a key role in a range of biological functions (15).

Red meat is also notable as a source of iron.

Specifically, it contains mainly heme iron. This is a form of iron that is found in animal-based products. It’s significant because heme iron is used and absorbed more efficiently (16).

Some other key nutrients in red meat include carnosine and creatine. These two compounds play key roles in muscle and brain function. Because they are primarily found in meat, people who do not eat meat may be frequently deficient in these nutrients (17,18,19).

Finally, the fatty acid profile is appealing because it contains low amounts of polyunsaturated fat.

Typically, this fatty acid profile is not popular because of the saturated fat, but as I mentioned before, saturated fat isn’t actually as bad as people tend to assume.

Inflammation

Another link that is often made is between red meat and inflammation.

Inflammation is an area of significant concern, particularly as there are many diseases associated with inflammation, such as arthritis.

I agree that inflammation is something to be concerned about, but there simply isn’t strong evidence that red meat increases inflammation – despite a few mechanisms being proposed for how this could occur.

One research study followed 60 participants in a randomized study that included a control group and a group that replaced some of the carbohydrates in their diet with lean red meat.

The research followed the participants for a period of 12 weeks and found that the consumption of red meat did not have any influence on inflammation or oxidative stress (20).

Another study compared a red meat diet to a diet rich in oily fish and found that there was no difference in inflammation between the two different groups (21).

It is certainly true that red meat, like many other fields, is an area of ongoing research. Nutrition is not an area that provides simple answers, particularly as the systems within the body are so complex and interact with one another.

For example, some recent research has suggested that the presence of L-carnitine in red meat may be associated with some negative health impacts (22).

However, research in this area is still in very early stages and there is currently insufficient scientific evidence to make any conclusions about what this finding may mean to meat consumption in humans.

Other research suggests that L-carnitine may not have negative health impacts at all, and may be associated with positive benefits (23).

Additionally, much of the research has been conducted in animals rather than humans and further research is needed to determine whether these aspects of red meat are relevant to human health.

Research Into Red Meat

Scientific research is a powerful tool, but it has its limitations.

I mentioned observational studies before, and this is a key issue that faces research into red meat. In fact, most of the studies that have found a link between red meat and cancer have been observational studies (e.g. 24,25,26).

Many of these studies haven’t even tried to distinguish between the consumption of processed and unprocessed meat.

The problem is that there are just so many different variables to look at. After all, the human body is a complex system. So much of what we do can impact the way that our body functions and the way that we respond to different things.

Indeed, authors have noted that these variables make it difficult to isolate what observed effects were actually the cause of red meat (27).

Another major issue surrounding research is that people only find what they are looking for.

This can be a real problem, because of how complicated the human body is. At the end of the day, researchers really don’t have the ability to know everything that they should be looking for.

An interesting example of this is the gut.

We know that there are many different types of beneficial bacteria that live in our gut. These are sometimes referred to as gut microbiota or the gut biome. These bacteria play a role in promoting our health and influencing the way that our bodies interact with the things we consume.

At the same time, our behaviors and eating choices can influence the composition of the gut microbiota. For example, some eating patterns could significantly change the bacteria present, resulting in negative impacts on health overall.

This may be happening for many people who eat red meat, because of the other aspects of their diet and lifestyle.

For example, behaviors, like eating less fruit and vegetables as well as consuming more sugar, refined flour and seed oils, are all more common in red meat eaters than those that don’t eat red meat. At the same time, those behaviors are all associated with negative changes to the bacteria in the gut (28,29,30).

Links have already been shown between changes to the gut microbiome and cancer (31,32).

That pattern could mean that changes in gut bacteria can lead to the development of cancer.

If that’s the case, then some of the observed impacts of processed meat or red meat on cancer could be the result of changes in the gut microbiome. It seems unlikely that red meat itself would cause that type of change. Instead, it could be the result of other aspects of people’s lifestyle and diet.

The worst part is that we simply do not know.

The gut microbiome is still a pretty new field of research. Because of this, the gut microbiome is an area that researchers into red meat typically don’t account for.

This is just one example of how the research into red meat is limited, especially the observational research. There may well be other areas that current research doesn’t consider which also play a role in the development of cancer or other health issues.

There have also been other pretty major issues with the research into red meat consumption.

For example, many studies tend to have incredibly low sample sizes. With scientific research in general, a higher sample size helps to ensure that the results of a study are accurate.

I mean, it just makes sense.

If you did a study on the health of 5 red meat eaters and 5 vegans, your outcomes wouldn’t mean a whole lot. After all, there is a huge amount of variation between different people who eat red meat and between different vegans.

Yet, studies with low sample sizes are sometimes used to ‘prove’ negative health outcomes of red meat. That’s a very inaccurate approach, especially when some red meat eaters have a healthy diet and lifestyle, while others don’t.

All of these issues highlight how difficult it is to be certain about any of the negative claims surrounding red meat.

Realistically, much more research is needed before we really know what impact red meat has on health – and that research needs to be better planned and better designed.

Beyond all of this, nutrition science is inherently complicated. It is incredibly difficult to accurately research and the studies that are conducted often don’t consider differences between individuals or how people behave in the long-term. The site Science Alert offers considerable insight into this topic and why there are no simple answers when it comes to nutrition.

Specific Diet Types

Most discussions on red meat assume that anyone who eats a lot of red meat must also have an unhealthy diet.

For many people this is true, as red meat is often associated with a heavier consumption of processed meat and processed food in general.

However, including red meat in the diet doesn’t have to be unhealthy. In fact, there are multiple healthy diet approaches that make use of considerable amounts of red meat.

One of these diets is the Paleo diet, which focuses on following a nutritional approach of our Paleolithic ancestors, rather than the modern day eating patterns. The site Nerd Fitness offers a great introduction to the diet and its underlying principles.

The Paleo diet is one that places a strong emphasis on eating significant amounts of meat while also cutting out a large number of food groups, including legumes, wheat, dairy (most of the time) and processed foods.

I talk more about Paleo in a post specifically on the Paleo diet, and I personally think it is a dietary approach that has some merit.

Many people have found the Paleo diet to be an effective way of losing weight and improving health, and others argue that Paleo acts as a good starting point for a healthy diet, rather than a set of hard and fast rules.

There are very few studies that directly consider the role of the Paleo diet in health or in weight loss, and most of the ones that are present are very low quality.

Nevertheless, the Paleo diet is likely to offer significant health effects simply as the result of its focus on red meat and the fact that it cuts out additives, processed foods and refined sugars.

A second diet type that follows the approach of eating red meat is Atkins, where followers limit carbs and get most of their calories from fat instead.

Even though this diet is sometimes subject to ridicule, it does have the potential to help people lose weight and improve health (33).

Additionally, there are also a large number of diets that are low-carb and high-fat, an approach that inherently lends itself to increased consumption of red meat.

The differences in diet type also cause a major issue for research.

For example, many studies simply focus on the amount of red meat that a person eats, rather than any other aspects of their diet.

Yet, a person on a Paleo diet, for example, will consume far fewer processed foods than the average red meat eater, even though the amount of red meat consumed may be similar.

Despite this, research tends to treat everybody who consumes red meat in a similar manner. In fact, there have been very few research studies that have seriously considered diets like the Paleo diet.

Modern Meat

One of the arguments against meat is that it is challenging for the body to digest.

This is true to an extent, but our bodies are well adjusted to eating red meat so this is not a good argument on its own.

Additionally, there are traditional populations that consume red meat regularly as part of their diet without negative health consequences, such as Masai populations (34).

The fact that red meat is a bit harder to digest comes from its protein content. This means that it does take the body longer to break down some of the components of red meat. But, that isn’t a bad thing.

Instead, this pattern means that red meat will tend to keep you full for a longer period of time. The fact that more energy is required for digestion is also a positive thing for your body.

However, it is important to note that the meat that we eat in the modern day and age is very different than what humans ate historically and this does have the potential to impact health.

For example, a large proportion of the meat that people eat is intensively farmed, a process that often involves providing animals with hormones and choosing their feed to promote specific types of meat.

Additionally, much of the meat that we consume is heavily processed, such as sausages and bacon.

Although I am primarily talking about red meat in this article, it is worth noting that some people focus on meat consumption in general, and this discussion often includes white meat, which is defined as meat that is white after it is cooked – such as chicken.

These differences mean that the health impacts of some types of meat are different than the health impacts of others.

In particular, most advocates of eating red meat argue that people should preferentially choose meat that is grass-fed and organic wherever possible.

For some people, this is an important ethical decision, while other people are more interested in the health benefits that grass-fed meat offers.

For example, one study found that grass-fed beef had a higher concentration of omega-3 fatty acids than corn-fed beef (35).

This makes grass-fed meat a much better choice, as improving the level of omega-3 in the diet is important for health, especially as a good ratio of omega-3 to omega-6 is needed to protect against cardiovascular disease (36).

Likewise, grass-fed beef tends to contain higher levels of vitamin A, vitamin E and CLA (a nutritious fatty acid) (37,38,39).

Because of this, grass-fed meat tends to be a much better option for health than corn-fed red meat.

In a similar manner, research has indicated that processed meat (like sausage) is linked to a higher risk of cardiovascular disease, while non-processed red meat (like steak) is not (16).

This study was actually particularly important, because it was so large in scope – however, it was still an observational study, so it did have some limitations.

Safety with Red Meat

When it comes to red meat, many of the health concerns are associated with effects that occur when meat is cooked.

In particular, when meat is cooked at high temperature, particularly when meat is burned or barbecued compounds are formed, including polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HCAs).

These compounds have been associated with mutations to DNA, which are associated with the formation of cancer (40).

This may mean that some observational studies are finding a link between red meat and cancer while the link may actually be between cooking method and cancer.

A good way of getting around this is to look for cooking methods that are not as harsh. For example, stewing and steaming are both great ways to cook meat. You can also marinade the meat, using ingredients like red wine or garlic.

If you do cook with high heat, be careful to turn the meat often. If part of the meat does get charred, the simple answer is just to cut that piece away prior to serving.

Nevertheless, the amount that red meat (or processed meat) contributes to cancer development is still relatively low. So, if you really want your meat charred, you would probably be okay, just be aware that doing so does increase your risk.

Is Red Meat Bad For You?

Even with all the arguments surrounding red meat and cancer, there is pretty scarce evidence that red meat has any negative impacts on health – especially if you focus just on unprocessed red meat.

Overall, there is very little actual evidence that meat causes negative health outcomes and significant evidence that a diet high in fat and low in carbs can have considerable health benefits.

There have simply not been any reliable controlled studies that link red meat to poor health or disease, and the results for observational studies do not have the power to be accurate.

Until I actually see randomized controlled research that shows that red meat has a negative health impact, I will continue to strongly support the idea that red meat is an important part of the diet and one that should not be avoided because of poor research.

Furthermore, as many people can attest, red meat is a tasty addition to any diet and avoiding it because of a myth that it is bad for health is simply not a good idea.

At the same time, red meat contains valuable nutritional elements. Many of those are hard to get in other places.

It all really comes back to one simple point.

There are many more significant things that you should be worrying about before you even think about red meat.

Not getting enough exercise, not getting enough fruit and vegetables, focusing on processed foods and simply eating too much food are all very serious food and lifestyle issues that contribute strongly to poor health.

Those areas are much more significant for health than red meat is, and you should be looking at them long before you look at red meat.

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