You’d be hard-pressed to find a health topic more widely debated than the case for or against eating red meat. That’s because medical opinion on whether or not we should be eating red meat ― and exactly how much of it we can safely eat ― is constantly changing.
For example, research published in the European Heart Journal linked daily consumption of red meat to tripling trimethylamine N-oxide (TMAO), a chemical linked to heart disease. That study was followed by an analysis published in Annals of Internal Medicine stating there didn’t seem to be a need to limit or restrict red meat consumption. (It was then discovered that the study was tied to a program that is partially backed by the beef industry.)
Needless to say, there’s a lot of murkiness. No wonder we’re all standing around scratching our heads as we ponder our next move in the grocery store. For most, including red meat in your diet doesn’t have to be an all-or-nothing approach (especially if you really crave it). But you should know how it affects you ― both good and bad.
Below experts explain what exactly happens when you eat red meat and how to modify your intake to create a well-rounded, healthy diet.
Red meat has been linked to some diseases like diabetes and cancer.
Eating red meat increases your body’s production of a hormone called insulin-like growth factor 1, or IGF-1. This could speed up the aging in the body along with cell replication that can increase the risk of multiple types of cancers, according to Joel Fuhrman a family physician and author of the forthcoming book Eat for Life.
“Insulin and IGF-1 hormones are tremendously important in the aging process,” Fuhrman said. “The diseases associated with aging ― cardiovascular disease, diabetes, cancer ― are driven by excessive activity of insulin and IGF-1, which in turn are driven by long-term excessive consumption of refined carbohydrates and animal protein.”
The World Health Organization classifies processed meat as a carcinogen and red meat as a “probable” carcinogen. Research published in Cancer Science found an increased risk of colon cancer among Japanese men with higher red meat intake, supporting the World Cancer Research Fund and American Institute for Cancer Research’s recommendation of eating only moderate amounts of red meat and little if any processed meat.
It can mess with your microbiome.
Your gut microbiome ― often referred to as your gut flora ― consists of all the microorganisms that reside in your digestive tract that help keep things running (no pun intended) smoothly.
“When you eat red meat, you are unnecessarily exposing your body to carcinogens, your blood flow is being compromised, oxidative stress and inflammatory markers are rising, and you are eating a food that provides no sustenance for your microbiome,” Fuhrman said.
And it doesn’t take long to do this, as a study published in Nature found short-term red meat consumption over a few days or weeks alters the microbiome, possibly leading to issues like inflammatory bowel disease.
Red meat does contain some useful vitamins.
Red meat does contain essential nutritional properties, like iron and vitamin B12, which are crucial to your overall well-being. Those who are iron deficient may be directed to eat red meat by their doctor, and this benefit of iron typically outweighs any possible adverse health effects depending on the patient. (You can also get these vitamins through a daily vitamin supplement, but don’t take one without advisement from your physician.)
So, how much red meat should you really eat?
While studies over the years have shown a link between heavy red meat diets and coronary heart disease, stroke, colorectal cancer and diabetes, further research shows that reducing red meat intake even slightly can have a big payoff.
Take, for example, a study published in Archives of Internal Medicine where Harvard researchers did a statistical analysis of two major health databases with over 100,000 men and women. The study found that every extra daily serving of unprocessed red meat (think steak, hamburgers, etc.) increased the risk of dying early by 13%, and eating extra processed red meat (like hot dogs and bacon) increased the risk by 20%.
More deaths could be prevented “if people ate fewer than .5 servings of meat per day [roughly 42 grams per day],” said Stephen Sinatra, a board-certified cardiologist and integrative cardiologist at Healthy Directions.
The World Cancer Research Fund’s experts state that if you do consume red meat, you should “limit your consumption to no more than about three portions per week,” which is equivalent to 12 to 18 ounces cooked. In other words, you don’t have to ditch the beef forever.
“My approach to diet is the 80-20 rule, that is, only 20% of consumption should be from animal sources, including fish, chicken, lamb, and buffalo,” Sinatra said. “If you want to make one of those servings organic red meat, that’s fine. But I wouldn’t make that your daily go-to source of protein.”
Fuhrman stresses that eating as much plant-based food ― think greens, seeds, beans and nuts ― as possible is the healthiest option overall.
“Plant-based foods are rich in antioxidants and phytochemicals that protect us from disease,” he said. “More natural plant foods and less animal products and processed foods is the secret to a long healthy life.”
Also on HuffPost
This article originally appeared on HuffPost.