Science Reveals How Red Meat Harms the Heart – HealthDay News
WEDNESDAY, Dec. 29, 2021 (HealthDay News) — Red-meat lovers may raise their risk of heart disease through a chain of events that plays out in the gut, a new study suggests.
Many studies over the years have tied diets heavy in red and processed meats to a heightened risk of heart disease and stroke. That type of evidence does not, however, prove red meat is the problem — or, if it is, why.
The new findings offer more clues about the “why.”
Researchers found that particular gut bacteria, more abundant in red-meat eaters, are key in turning a dietary nutrient called carnitine into a foe: a chemical known as TMAO, which helps promote blood-clotting and clogged arteries.
For the average person, the insights reinforce what’s already known about heart-healthy eating, said study co-author Dr. Stanley Hazen, who directs Cleveland Clinic’s Center for Microbiome and Human Health.
In particular, he pointed to the traditional Mediterranean diet, which has been shown in clinical trials to cut the risks of heart disease and stroke.
That diet is high in fish, fruits and vegetables, legumes, olive oil and nuts — and low in red meat and processed foods.
The new study was published Dec. 23 in Nature Microbiology. It is among the latest to delve into the relationship among diet, the gut microbiome and human health.
“Microbiome” refers to the vast collection of bacteria and other microbes that naturally inhabit the human body, especially the gut. Research in recent years has begun to reveal just how vital those gut microbes are — not only in digestion, but in immune system defenses, brain function and the health of the cardiovascular system.
It’s well-established, Hazen said, that people with diets high in red meat typically have a higher risk of heart disease and stroke than those who eat little red meat.
The traditional suspect was saturated fat, found almost exclusively in animal products. Saturated fat can boost “bad” LDL cholesterol, which contributes to cardiovascular disease.
But, Hazen said, research has shown that any ill effects of saturated fat are not enough to explain the excess heart disease risks linked to heavy red-meat consumption. There had to be other mechanisms.
The new findings point to one, said Lauri Wright, chair of nutrition and dietetics at the University of North Florida, in Jacksonville.
There is still much to learn about the gut microbiome, said Wright, who is also a spokesperson for the Academy of Nutrition and Dietetics. But in general, she said, diets rich in foods like vegetables, fruits and high-fiber grains help “feed” beneficial gut microbes.