For years now, large studies have shown us the connection between red meat and poor heart function.
These dangers have largely been attributed to the fat and cholesterol in red meat.
Yet for older Americans, meat provides much-needed protein that offsets the loss of muscle mass and strength that comes as we age.
For this reason, a group of researchers has looked more deeply into the link between red meat intake and heart disease, with some surprising results…
It’s NOT all about cholesterol
The study followed nearly 4000 subjects for a median of 12.5 years. The average age at the start of the study was 73 years old.
Results indicated that, for each serving per of red meat per day, the risk of cardiovascular disease jumps 22 percent.
But why?
The “age-old wisdom” is that the cholesterol and fat found in red meat can harm the arteries and cause heart disease.
But Meng Weng, a postdoctoral fellow at Tufts University and lead researcher of this study, and her team found something completely different…
It seems that about ten percent of that increased risk is linked to three key metabolites created in the gut by the bacteria that dwell there when we eat meat.
“The interactions between red meat, our gut microbiome, and the bioactive metabolites they generate seem to be an important pathway for risk, which creates a new target for possible interventions to reduce heart disease.”
Trimethylamine N-oxide (TMAO) and two related metabolites (gamma-butyrobetaine and crotonobetaine, derived from L-carnitine, which is abundant in red meat) were associated with an elevated risk of heart disease.
There were more surprises as well…
“Interestingly, we identified three major pathways that help explain the links between red and processed meat and cardiovascular disease — microbiome-related metabolites like TMAO, blood glucose levels, and general inflammation — and each of these appeared more important than pathways related to blood cholesterol or blood pressure,” said co-senior author, Dariush Mozaffarian, dean for policy at the Friedman School.
More reason to cut back on red meat
This isn’t the first time TMAO has been linked to major cardiovascular problems.
Taking both the old knowledge and new findings into account, it’s certainly still a good idea to cut back on red meat as much as you can, whether cholesterol is involved or not.
And the good news is that the higher risk and connections to gut bacterial metabolites were found for red meat but not poultry, eggs, or fish.
So if heart disease is a concern, cut down on red meat and enjoy safer protein sources.
If you’re looking for the ultimate heart-healthy diet that still gives you plenty of protein, you might want to give the pesco-Mediterranean diet a try.
As far as processed meats go, the potential damage is a little more clear-cut.
Not only does eating processed meat increase inflammation, but research has found strong disease links. For example, bacon has been linked to cognitive decline and dementia.
Sources:
Research links red meat intake, gut microbiome, and cardiovascular disease in older adults — Eureka Alert
Dietary Meat, Trimethylamine N-Oxide-Related Metabolites, and Incident Cardiovascular Disease Among Older Adults: The Cardiovascular Health Study — American Heart Association Journals