Looking for lecithin
Stanley Hazen is head of preventative medicine at the Cleveland Clinic. He’s looking at the label on a package of soft and chewy cookies…

“ There it is, right there; lecithin, boom, right on the label.”

Hazen is one of the authors of a study published in the journal Nature that shows the food additive lecithin, once it reaches our gut, can lead to heart disease.

“And we were able to see that higher levels of this metabolite made by the gut flora was associated with higher risk of having cardiovascular disease.”

You are not human
 The research provides a new understanding of the causes of heart disease.

“We used to say that it was due to their genes, (and) that’s part of the story. But perhaps (an) even a bigger part of the story is the intestinal flora.”

Our bodies host hundreds of billions of bacteria, mostly in our large intestine. Together they form a virtual organ within an organ, which helps us absorb nutrients from food and fight food-born pathogens.

Dr. Steven Zeisel is director of research at the University of North Carolina. He says the importance of our inner ecology is only now being realized.

“You think you’re a human being, but you have 10 times more bacterial DNA in you than you have human DNA."

“It’s been in front of us for years, but we’ve been blind to thinking about it. And now everybody is thinking about what gut bacteria be doing.”

T-MANO -  a new concern for heart health
What the bacteria in our gut should be doing is taking this ubiquitous food additive, lecithin, and converting it into a chemical called trimethylamine N-oxide, or T-MANO. And that, says the Cleveland Clinic’s Stanley Hazen, causes heart disease.

“Those individuals with a higher plasma level of the gut flora metabolite called T-MANO, it predicts future risk of heart attack, stroke, or death quite strongly -- in fact, stronger than traditional risk markers.”

Hazen thinks we could see T-MANO added to the list of markers like cholesterol, LDL, HDL, and triglycerides that doctors now use to measure heart health.

Hazen is concerned because lecithin is in everything from non-stick spray to baby formula. It’s the ingredient that makes cookies soft, margarine spreadable, and chocolate milk mix.

“The food engineers are adding things, thinking it’s harmless from a health standpoint like lecithin, which is the exact same thing that gives rise to this pro-atherosclerotic metabolite by our gut flora.”

Lecithin is safe
Joe Casey is head of the lecithin division of St.Louis-based Solae Corporation. The company produces about a third of the 180-thousand tons of lecithin that go into food each year in the U.S. He’s not concerned about negative effects of the additive.

“It’s only one study, and generally long term conclusions are based on a body of research and a body of literature not individual studies.”

In fact, far from a health risk, Casey is one of the millions of people who believe lecithin can lower cholesterol and boost brain function.

“I take 15 grams of lecithin every day because of the health benefits of lecithin.”

But the University of North Carolina’s Steven Zeisel says that’s a little more than we need. He says lecithin IS a major source of an essential nutrient, choline, but too much can be harmful.

“This is a warning: Don’t go mega-dosing yourself just because you have the idea a little is good but a lot is better. That’s usually not true, especially in nutrition.”

Moderation in all things
Zeisel says the body benefits from lecithin in moderate amounts. Most of it is absorbed by the small intestine before it encounters the gut bacteria further downstream. So it doesn’t get converted into T-mano. And therefore, it’s not generally a health risk.

He adds that the Cleveland Clinic’s research is significant because it’s the first to link the gut to the heart.

But the main lesson is one shared with many other studies: Like everything else in nature, there’s the right amount, and then there’s too much, especially when it comes to food. And food additives.


I'm Jeff St.Clair with this week's Exploradio


4/18/12 10:30am

The Cleveland Clinic study that links a common food additive, gut bacteria, and heart disease was named today as one of the top 10 research studies of the year by the Clinical Research Forum.   The Washington D.C. based Clinical Research Forum is a nonprofit organization is comprised of the nation's most prestigious academic medical centers and professional organizations.  The Cleveland Clinic is partnering with North Carolina-based Liposcience to develop a diagnostic test for the metabolite.