(CBS News) -- A report published Wednesday in the New England Journal of Medicine said red meat and eggs are linked to heart disease.
That's no surprise. But what is surprising in this report is why. Turns out there is something inside the human body that may trigger ill effects.
The new research shows it's not just what we eat, but how we digest it that may lead to heart disease.
Dr. Stanley Hazen, of the Cleveland Clinic, led the study.
"A simple blood test of a compound that's ultimately made by gut bacteria serves as a very strong and independent predictor of future risk of heart attack, stroke and death," he said.
Foods such as eggs and meat have high amounts of a fatty substance called lecithin.
Bacteria in the intestines digest the lecithin, producing a chemical called TMAO. The TMAO enters the blood stream where it can potentially make it more likely for arteries to clog.
Researchers followed more than 4000 patients with suspected heart disease for three years. Those with the highest TMAO levels were two-and-half times more likely to have a major cardiovascular event than those with the lowest levels.
"This blood test, TMAO, helped identify people who were at risk for experiencing a major adverse cardiac event, heart attack, stroke, or death in the ensuing three years, even in the absence of having established heart disease or cardiac risk factors," said Hazen.
(Left: A new study questions the value of a vitamin taken by millions to prevent heart attack and stroke)
In addition, when researchers lowered the amount of gut bacteria, their TMAO levels also dropped, raising the intriguing possibility that heart disease might be prevented or treated by developing new drugs to lower TMAO levels.
So is TMAO as big a risk factor as high cholesterol?
We know that people with normal or even low cholesterol levels can go on to have a heart attack. If this research pans out, it may turn out that a high TMAO level helps identify those people.
The big question is, does lowering the TMAO level, lower the risk of a heart attack?