What exactly is a heart-healthy diet?

A grocery shopping trip, arranged by the University of California at Davis, for people with heart disease turns out to not be so simple.

As far back as a 1972, a public-service announcement from the American Heart Association carried a simple message — pig out and you'll clog your arteries. But these days a lot of the emphasis is on eating the right foods to protect your heart.

A lot of people talk about a heart-healthy diet, but the details are surprisingly complex and changing. The biggest change is the move away from the idea that all fat is bad.

So what is still bad? Fats from meat: so-called “saturated fat” tops the list. Margarine: not long ago heart experts encouraged people to use it. But many margarines and processed foods contain something called “trans-fats” and those are just as dangerous as animal fats.

What is good? Fats from fish and from vegetables, like olive oil, are good for the heart.

Eggs, once villains, are no longer seen as a threat to raising cholesterol. According to Dr. Kenny Jialal, “I am not adverse to people having eggs as part of a heart-healthy diet.”

Heart nutrition experts like Jialal can understand the public’s frustration. “I think there’s confusion with the diet. But, you know, it’s a moving target.”

It's a moving target because scientists are constantly carrying out experiments to find heart-healthy foods. They are currently testing vitamin E, orange juice with additives called sterols, and lycopeine, a nutrient found in tomatoes.

But for many heart patients, like Michael Guzman, the education is not so difficult because they have so far to go. “I didn’t eat vegetables!” explains Guzman.

Despite all the changing guidelines, one piece of advice that remains constant is your mother’s: eat your fruits and vegetables.

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