Red meat causes heart disease. Except when it doesn’t?

One study says reduce red meat consumption; another says enjoy. Which should we believe?

Red meat causes heart disease. Except when it doesn’t?
  • A recent meta-analysis found red and processed meats increased the risk of developing heart disease by 3–7 percent.
  • The study comes just months after an infamous review claimed Americans did not need to change their meat-eating ways.
  • The problem is not scientific consensus, but how specialists analyze risk when proffering public guidelines.


Americans love meat. Love it! Worldwide, a person consumes on average 92 pounds of meat per year. The average American flesh-eater devours more than 265.

Most of that meat is poultry, which has dominated the dinner table slot since about the turn of the century. When you consider that the average chicken weighs 6 pounds at the time of slaughter, that's, wow, so many dead birds.

That isn't to say that Americans have given up on red or processed meats. Since the 1950s, red meat has been a symbol of American prosperity, and while our consumption has declined steadily since the beef lust of the 1970s, we still maintain our love of grilled steaks, juicy burgers, and cold-cut mountains sandwiched in bread. A majority of those polled in a 2012 survey said they eat red meat one to four times a week, a figure that excludes poultry and fish.

But even that may be too much. According to a meta-analysis published in JAMA Internal Medicine, just two servings of red meat and processed meats a week is associated with an increased risk of cardiovascular disease and death. And poultry isn't an entirely benign alternative, either.

A red meat menace

Red meat is associated with an increased, though slight, risk of developing heart disease.

(Photo: Kaleb Snay/U.S. Air Force)

The researchers analyzed six cohort studies, totaling 29,682 participants. The participants were surveyed about their eating habits and health. Baseline data were collected from 1985 to 2002 with follow-ups conducted until August 2016.

The researchers found two servings of processed meats a week to be associated with a 7 percent higher risk of developing cardiovascular disease — or an absolute risk difference of about 2 percent. Two servings of red meat were associated with a 3 percent higher risk — or about 1 percent absolute risk — and poultry was associated with similar risk. Fish consumption showed no increased risk.

The researchers then looked at all-cause mortality. They found a 3 percent higher risk of premature death for servings of red and processed meats, but no difference for poultry or fish.

"Modifying intake of these animal protein foods may be an important strategy to help reduce the risk of cardiovascular disease and premature death at a population level," lead study author Victor Zhong said in a release.

In the heart or in the head?

But a meta-analysis published last year said that Americans don't have to change their meat habits.

(Photo: Pixabay)

You may now be thinking, "Wait! Wasn't there a study last year that said it was okay to eat red meat?' Yes, yes there was.

That meta-analysis, published in the Annals of Internal Medicine in October, was based on four systematic reviews of trials and studies looking at the link between red and processed meat consumption and cancer, cardiovascular disease, and mortality.

In one review, the researchers looked at 12 trials — totaling 54,000 participants — and found no significant association between meat consumption and the risk of heart disease or cancer. In the other three, they looked at studies of all-cause mortality, totaling four million participants. They found a very small reduction in risk but an uncertain association.

The researchers ultimately concluded that the links were small, the risks low, and the quality of evidence lacking. As a result, they recommended that adults continue to eat red and processed meats at their current levels and saw no reason to reduce consumption for health.

"This is not just another study on red and processed meat, but a series of high-quality systematic reviews resulting in recommendations we think are far more transparent, robust and reliable," Bradley Johnston, an epidemiologist at Dalhousie University and the study's corresponding author, said in a release.

However, many nutritionists and organizations like the American Heart Association and the American Cancer Society came out against the study and pushed for its publication to be withheld.

"This new red meat and processed meat recommendation was based on flawed methodology and a misinterpretation of nutritional evidence," Frank Hu, chair of the Department of Nutrition at Harvard, said. "The authors used a method often applied to randomized clinical trials for drugs and devices, which is typically not feasible in nutritional studies."

Nutritional data and you

What should we take away from this back-and-forth between nutritionists? First, both studies found that people who reduce red and processed meat consumption lowered their risk of premature mortality. They also found that the risk reduction was small.

The difference lies in how they believe that risk should be communicated to the public and how people should navigate their daily diets.

"The standards of evidence for the [scientific conclusions] are scientific matters and should not depend on extra scientific considerations" David Allison, dean of the Indiana University School of Public Health, told the New York Times added. "The standards of evidence for the [recommendations] are matters of personal judgment or in some cases legislation."

Red meat and processed foods are associated with a low risk of developing cancer and heart disease. That's a scientific consensus. That's not the same as saying whether individual people should or should not consume those meats.

For example, if changing dietary habits reduces the risk of heart disease by 3 percent, that means only three in one hundred people would statistically see the benefits. The vast majority, 97 people, won't. That's the view of the Annals of Internal Medicine's recommendation: The current guidelines won't change much on an individual level.

On the other hand, spread that risk across an entire population, and the salubrious effects become staggering. For the U.S.'s 327 million people, a reduced risk of 3 percent means 9,810,000 fewer people suffering from heart disease. Since health recommendations are generalized for an entire population, it makes sense that experts target individual advice with the public in mind.

Aaron Carroll, a physician and author of the Bad Food Bible, has written and spoken a lot on this topic. His advice is as follows: "If you're eating multiple servings of red meat a day, then you may want to cut back. If you eat a couple of servings a week, then you're likely just fine."

Moving away from meat, nutritional research also agrees what the average person should eat on a daily basis. In an interview with Big Think, David Katz, director of the Yale Prevention Research Center, summed up the findings nicely:

You want to eat fish? Eat fish. You want to eat seafood? Eat seafood. You want to eat some lean meat? Do. You want to eat eggs? Do. You want to eat dairy? Do. But the bulk of your diet should be vegetables, fruits, whole grains, beans, lentils, nuts, and seeds. This is true all around the world where people do the best.

If you choose to eat meat, well, you do you. But you do you at your own risk.

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7 most notorious and excessive Roman Emperors

These Roman Emperors were infamous for their debauchery and cruelty.

Nero's Torches. A group of early Christian martyrs about to be burned alive during the reign of emperor Nero in 64 AD.

1876. Painted by Henryk Siemiradzki.
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  • Roman Emperors were known for their excesses and violent behavior.
  • From Caligula to Elagabalus, the emperors exercised total power in the service of their often-strange desires.
  • Most of these emperors met violent ends themselves.

We rightfully complain about many of our politicians and leaders today, but historically speaking, humanity has seen much worse. Arguably no set of rulers has been as debauched, ingenious in their cruelty, and prone to excess as the Roman Emperors.

While this list is certainly not exhaustive, here are seven Roman rulers who were perhaps the worst of the worst in what was one of the largest empires that ever existed, lasting for over a thousand years.

1. Caligula

Officially known as Gaius (Gaius Caesar Augustus Germanicus), Caligula was the third Roman Emperor, ruling from 37 to 41 AD. He acquired the nickname "Caligula" (meaning "little [soldier's] boot") from his father's soldiers during a campaign.

While recognized for some positive measures in the early days of his rule, he became famous throughout the ages as an absolutely insane emperor, who killed anyone when it pleased him, spent exorbitantly, was obsessed with perverse sex, and proclaimed himself to be a living god.

Caligula gives his horse Incitatus a drink during a banquet. Credit: An engraving by Persichini from a drawing by Pinelli, from "The History of the Roman Emperors" from Augustus to Constantine, by Jean Baptiste Louis Crevier. 1836.

Among his litany of misdeeds, according to the accounts of Caligula's contemporaries Philo of Alexandria and Seneca the Younger, he was accused of sleeping with other men's wives and publicly talking about it, as well as killing for mere amusement. Supposedly, during one competition he was presiding over, he got so bored that he had his guards throw a whole section of the audience into the arena during the intermission so they would be eaten by wild beasts as no prisoners were available. He also allegedly executed two consuls who forgot his birthday.

He was also said to have caused mass starvation and purposefully wasted money and resources, like making his troops stage fake battles just for theater. If that wasn't enough, he turned his palace into a brothel and was accused of incest with his sisters, Agrippina the Younger, Drusilla, and Livilla, whom he also prostituted to other men. Perhaps most famously, he was planning to appoint his favorite horse Incitatus a consul and went as far as making the horse into a priest.

In early 41 AD, Caligula was assassinated by a conspiracy of Praetorian Guard officers, senators, and other members of the court.

2. Nero

Fully named Nero Claudius Caesar, Nero ruled from 54 to 68 AD and was arguably an even worse madman than his uncle Caligula. He had his step-brother Britannicus killed, his wife Octavia executed, and his mother Agrippina stabbed and murdered. He personally kicked to death his lover Poppeaea while she was pregnant with his child — a horrific action the Roman historian Tacitus depicted as "a casual outburst of rage."

He spent exorbitantly and built a 100-foot-tall bronze statue of himself called the Colossus Neronis.

He is also remembered for being strangely obsessed with music. He sang and played the lyre, although it's not likely he really fiddled as Rome burned in what is a popular myth about this crazed tyrant. As misplaced retribution for the fire which burned down a sizable portion of Rome in the year 64, he executed scores of early Christians, some of them outfitted in animal skins and brutalized by dogs, with others he burned at the stake.

Roman Emperor Nero in the burning ruins of Rome. July 64 AD.Credit: From an original painting by S.J. Ferris. (Photo by Kean Collection / Getty Images)

He died by suicide.

3. Commodus

Like some of his counterparts, Commodus (a.k.a. Lucius Aelius Aurelius Commodus) thought he was a god — in his case, a reincarnation of the Greek demi-god Hercules. Ruling from 176 to 192 AD, he was also known for his debauched ways and strange stunts that seemed designed to affirm his divine status. Numerous statues around the empire showed him as Hercules, a warrior who fought both men and beasts. He fought hundreds of exotic animals in an arena like a gladiator, confusing and terrifying his subjects. Once, he killed 100 lions in a single day.

Emperor Commodus (Joaquin Phoenix) questions the loyalty of his sister Lucilla (Connie Nielsen) In Dreamworks Pictures' and Universal Pictures' Oscar-winning drama "Gladiator," directed by Ridley Scott.Credit: Photo By Getty Images

A burning desire to fight both animals and humans as a gladiator for the New Year's Day celebrations in 193 AD brought about his demise. After Commodus shot hundreds of animals with arrows and javelins every morning as part of the Plebeian Games leading up to New Year's, his fitness coach (aptly named Narcissus), choked the emperor to death in his bath.

4. Elagabalus

Officially named Marcus Aurelius Antoninus II, Elagabalus's nickname comes from his priesthood in the cult of the Syrian god Elagabal. Ruling as emperor from 218 to 222 AD, he was so devoted to the cult, which he tried to spread in Rome, that he had himself circumcised to prove his dedication. He further offended the religious sensitivities of his compatriots by essentially replacing the main Roman god Jupiter with Elagabal as the chief deity. In another nod to his convictions, he installed on Palatine Hill a conical fetish made of black stone as a symbol of the Syrian sun god Sol Invictus Elagabalus.

His sexual proclivities were also not well received at the time. He was likely transgender (wearing makeup and wigs), had five marriages, and was quite open about his male lovers. According to the Roman historian (and the emperor's contemporary) Cassius Dio, Elagabalus prostituted himself in brothels and taverns and was one of the first historical figures on record to be looking for sex reassignment surgery.

He was eventually murdered in 222 in an assassination plot engineered by his own grandmother Julia Maesa.

5. Vitellius

Emperor for just eight months, from April 19th to December 20th of the year 69 AD, Vitellius made some key administrative contributions to the empire but is ultimately remembered as a cruel glutton. He was described by the Roman historian Suetonius as overly fond of eating and drinking, to the point where he would eat at banquets four times a day while sending out the Roman navy to get him rare foods. He also had little social grace, inviting himself over to the houses of different noblemen to eat at their banquets, too.

Vitellius dragged through the streets of Rome.Credit: Georges Rochegrosse. 1883.

He was also quite vicious and reportedly either had his own mother starved to death or approved a poison with which she committed suicide.

Vitellius was ultimately murdered in brutal fashion by supporters of the rival emperor Vespasian, who dragged him through Rome's streets, then likely beheaded him and threw his body into the Tiber river. "Yet I was once your emperor," were supposedly his last words, wrote historian Cassius Dio.

6. Caracalla

Marcus Aurelius Antoninus I ruled Rome from 211 to 217 AD on his own (while previously co-ruling with his father Septimius Severus from 198). "Caracalla"' was his nickname, referencing a hooded coat from Gaul that he brought into Roman fashion.

He started off his rise to individual power by murdering his younger brother Geta, who was named co-heir by their father. Caracalla's bloodthirsty tyranny didn't stop there. He wiped out Geta's supporters and was known to execute any opponents to his or Roman rule. For instance, he slaughtered up to 20,000 citizens of Alexandria after a local theatrical satire dared to mock him.

Geta Dying in His Mother's Arms.Credit: Jacques Pajou (1766-1828)

One of the positive outcomes of his rule was the Edict of Caracalla, which gave Roman citizenship to all free men in the empire. He was also known for building gigantic baths.

Like others on this list, Caracalla met a brutal end, being assassinated by army officers, including the Praetorian prefect Opellius Macrinus, who installed himself as the next emperor.

7. Tiberius

As the second emperor, Tiberius (ruling from 42 BC to 16 AD) is known for a number of accomplishments, especially his military exploits. He was one of the Roman Empire's most successful generals, conquering Pannonia, Dalmatia, Raetia, and parts of Germania.

He was also remembered by his contemporaries as a rather sullen, perverse, and angry man. In the chapter on his life from The Lives of the Twelve Caesars by the historian Suetonius, Tiberius is said to have been disliked from an early age for his personality by even his family. Suetonius wrote that his mother Antonia often called him "an abortion of a man, that had been only begun, but never finished, by nature."

"Orgy of the Times of Tiberius on Capri".Painting by Henryk Siemiradzki. 1881.

Suetonius also paints a damning picture of Tiberius after he retreated from public life to the island of Capri. His years on the island would put Jeffrey Epstein to shame. A horrendous pedophile, Tiberius had a reputation for "depravities that one can hardly bear to tell or be told, let alone believe," Suetonius wrote, describing how "in Capri's woods and groves he arranged a number of nooks of venery where boys and girls got up as Pans and nymphs solicited outside bowers and grottoes: people openly called this 'the old goat's garden,' punning on the island's name."

There's much, much more — far too salacious and, frankly, disgusting to repeat here. For the intrepid or morbidly curious reader, here's a link for more information.

After he died, Tiberius was succeeded in emperorship by his grandnephew and adopted grandson Caligula. How fitting.

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