Meat Fit into a Healthy Diet

 

The meat debate is both complicated and divisive. Nutrition experts have sent mixed messages for years. The conversations are not only about meat’s direct health effects but also its environmental effects.

There are reasons to eat meat and to avoid it, but few people can agree on just what meat does for our bodies or how it affects the planet. Some people consider meat to be a fantastic source of nutrients, while others argue that it’s harmful to human health.

For every claim that meat might cure a chronic illness, there seems to be another claim implying that meat causes heart disease and cancer.

Some sources say meat is environmentally-friendly, and others say meat production contributes to deforestation.

This article attempts to untangle the meat debate from a health-based perspective and uncover the pros and cons of eating meat.

 

How different cultures define meat

Meat is the flesh and other edible parts of animals, such as mammals and birds, that humans prepare and consume.

In the United States and many other countries, the term “meat” mainly refers to the muscle tissue and fat of mammals and birds. But meat may also include other edible tissues, such as organs.

Particularly liver, kidneys, brains, and intestines — has historically been eaten in most civilizations. However, it’s fallen out of favor in some parts of the West. Offal remains popular in various cultures throughout the world, particularly among traditional societies.

Many delicacies are also organ-based.

Foie gras is a traditional French specialty made from duck or goose liver. Sweetbreads comprise meat from the thymus gland and have been eaten in Europe since Roman times, and Menudo is a traditional meat dish in Mexico including beef stomach and meat in broth.

Nowadays, meat is produced on farms. Most commercial meat products come from domesticated animals kept in huge industrial facilities that may house hundreds or even thousands of animals at once.

In some traditional societies, though, hunting animals is the only way to obtain meat.

Meat is generally eaten after it has been cooked, sometimes after being cured or smoked. It’s often eaten as steak, chops, ribs, or roast and can also be found in powdered or ground forms.

Meat can be cooked in or served with a sauce, condiment, or side dish, which may be dipped into the meat juices.

Types of meat we can eat

Meat is classified according to the animal from which it comes, as well as how it’s prepared.

Red meat

Red meat is higher than white meat in myoglobin, a protein that’s high in iron and found only in mammals. The following are some examples:

• beef (cattle)
• pork (pigs and hogs)
• lamb
• veal (calves)
• goat
• game, such as bison, elk, and venison (deer)

White meat

White meat refers to flesh that is light in color before and after cooking, as opposed to red meat. The phrase often includes all birds, even if their flesh appears red in reality, as in the case of duck meat. Other examples include:
• chicken
• turkey
• goose
• wild birds, such as quail and pheasant

Processed meat

The term “processed meat” refers to red or white meats that have been “treated” in some way. It might be preserved or enhanced in various forms, such as by salting, curing, smoking, drying, or other processes. Examples include:

• hot dogs
• sausage
• bacon
• luncheon (deli) meats, such as bologna, salami, and pastrami
• jerky

Reviewing the main nutrients in meat

Fresh meat is regarded as a valuable source of high quality protein.

When a protein contains all 9 amino acids (the building blocks of protein) that your body needs in adequate amounts, it’s thought to have high biological value and can be considered a complete protein.

After cooking, meat contains approximately 25–30% protein by weight.

A 3.5-ounce (100-gram) serving of cooked chicken breast contains about 31 grams of protein, while the same serving size from beef provides 27 grams.

Here’s a look at the nutritional content of a 3.5-ounce (100-gram) serving of lean beef.

• Calories: 205
• Protein: about 27 grams
• Riboflavin: 15% of the Daily Value 
• Niacin: 24% 
• Vitamin B6: 19% 
• Vitamin B12: 158%
• Iron: 16% 
• Phosphorus: 19% 
• Zinc: 68% 
• Selenium: 36% 

Other muscle meats have similar nutrient profiles, although they contain less zinc.

Pork is particularly rich in thiamine. For example, pork chops provide 78% of the DV per 5.5-ounce (157-gram) serving.

Vitamin A, B12, iron, and selenium are present in significant amounts in liver and other organ meats. These meats are also excellent sources of choline, an important nutrient for brain, muscle, and liver health.

Meat consumption and cancer risk

Some people insist that eating meat raises cancer risk. However, that probably depends on the type of meat you eat.

There is convincing evidence that eating processed meat leads to cancer, especially colorectal cancer. The IARC reviewed epidemiological research linking cancer in humans with eating processed meats.

Furthermore, there is strong — but limited — evidence linking red meat consumption to colorectal cancer. Pancreatic and prostate cancers have likewise been connected. As a result, the IARC classifies red meat as “probably carcinogenic to humans”.

Other research links a high intake of red meat to cancers of the digestive tract, kidney, and bladder.

Although no definite link between eating meat and breast cancer has been established, diet may significantly influence breast cancer prognosis.

Eating a healthy diet high in fruits, vegetables, and whole grains and low in meat may improve outcomes of early-stage breast cancer.

A recent review of observational and experimental studies suggests that eating meat may induce direct DNA damage, which is known as genotoxicity. However, the researchers acknowledged that some of the studies in the review were flawed.

Of all cancers, colon cancer has the strongest association with processed and red meat intake, with dozens of studies documenting a link.

Overall, more high quality research is needed to further explore the relationships between meat and cancer.

The connection between meat and heart disease

A significant number of large observational studies have linked meat consumption to a higher chance of developing heart disease.

Recent research including 43,272 men found that eating unprocessed or processed red meat was linked to a slightly increased risk of heart disease.

In an older review of 20 studies among more than 1.2 million people, researchers found that consuming processed meat appeared to increase heart disease risk by 42%. Although, they didn’t uncover a link between red meat and heart disease.

One study found that people who ate a diet high in red meat had three times the amount of trimethylamine N-oxide (TMAO) — a compound linked to heart disease — compared with those who ate a diet heavy in white meat or plant-based protein.

However, these studies don’t prove that a high intake of meat causes heart disease. They only show an association.

Additionally, some controlled studies and older research have found that frequent meat consumption, including high fat varieties, has a neutral or beneficial effect on heart disease risk factors.

The connection between meat and type 2 diabetes

Several large studies have shown an association between processed or red meat and type 2 diabetes.

Eating meat raises the risk of type 2 diabetes by 22%, according to a recent meta-analysis of epidemiological research.

An older review of 3 studies found that consuming more than half a serving of red meat daily increased the risk of developing diabetes within 4 years by 30%, in part related to weight gain.

However, the science of nutrition is anything but straightforward.

It’s likely that those who developed diabetes had other contributing risk factors, such as genetic or environmental factors. Dietary behaviors may have also played a role, including eating too many refined carbs, consuming insufficient vegetables, or consistently overeating.

The connection between meat and weight gain

However, more research is needed, as the relationship between meat consumption and weight gain isn’t totally clear.

For example, the results from individual studies vary greatly.

Plus, these studies are observational, and they don’t account for other types and amounts of food consumed regularly. It’s also important to remember that many factors aside from diet can influence a person’s weight, such as genetics, sleep quality, and activity level.

A study of 170 countries’ obesity rates found that the availability of meat explained 50% of the variation in rates after adjusting for wealth, calorie consumption, urbanization levels, and physical inactivity, all of which significantly contribute to increased body weight (43).

In other words, high meat availability may be associated with an increased prevalence of obesity.

Although red meat is frequently linked to weight gain and white meat isn’t, one controlled study found no difference in weight changes among people with excess weight who were assigned to eat beef, pork, or chicken for 3 months.

Another study in people with prediabetes found that weight loss and body composition improvements were similar among those who consumed diets based on animal or plant protein.

Either way, it appears that consuming a plant-heavy or plant-based diet supports healthy weights, regardless of whether meat is consumed.

A plant-heavy diet should be rich in whole foods, which are minimally or not at all processed, especially fresh fruits and vegetables.

But that doesn’t mean meat can’t fit into a well-rounded diet.

For example, a recent meta-analysis revealed that the Paleolithic (paleo) diet — which centers whole foods, includes meat, and excludes grains and processed foods — might help people lose weight, reduce their waist circumference, and help manage chronic disease.

The paleo diet is a subset of diets that follow what many proponents believe to be the eating patterns of people during the Paleolithic era. It comprises lean meats, fish, fruits, vegetables, nuts, and seeds — foods that may have been hunted or foraged in the past.

To verify its health advantages, however, more randomized clinical trials with a larger number of participants and longer duration are required.

If you’re considering changing to a plant-based, paleo, or other diet plan, be sure to talk with a healthcare professional first. They can help you explore new eating habits while ensuring you get the nutrients you need and maintain a healthy relationship with food.