A recent study funded by the National Cattlemen’s Beef Association found that eating a Mediterranean-style diet with lean beef leads to lower levels of a chemical called TMAO compared to a typical American diet with the same amount of beef. TMAO is made by gut bacteria and is linked to a higher risk of heart disease.
Researchers ran a controlled feeding trial with 30 healthy adults. The participants followed different diets: Mediterranean diets with 14, 71, or 156 grams of lean beef per 2,000 calories, and a typical American diet with 71 grams of beef. Each diet lasted four weeks, with a one-week break in between.
Samples of blood, urine, and feces were collected to study gut bacteria and levels of TMAO. Compared to the American diet, the Mediterranean-style diets had less sodium, more healthy fats, fiber, and protein. The American diet had more carbohydrates and unhealthy saturated fats.
The results showed that the Mediterranean-style diets had higher gut bacteria diversity and much lower TMAO levels in blood and urine. Increasing the amount of lean beef in the Mediterranean diet did not raise TMAO levels.
This suggests that the overall diet, not beef alone, influences TMAO levels. However, since the study was funded by a beef industry group, the findings should be viewed with care. Also, TMAO was not the main goal of the original trial.
In conclusion, eating lean beef as part of a Mediterranean diet may reduce some heart risks, but more long-term research is needed.
If you care about heart health, please read studies about a new cause of heart rhythm disorders and eating just one cup of nitrate-rich vegetables daily can reduce heart disease risk.
For more about heart health, please read studies about blood thinners that may not prevent stroke in people with heartbeat problems and this diabetes drug may protect heart health in older veterans.
The study is published in the Journal of the American Heart Association.
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