My doc was pleased that my blood tests had improved. “Cholesterol’s down,” he reassured me.

Yay. Trying to avoid excess saturated fat in my diet paid off.

Then he handed me a copy — hot off the press — of a report in the Annals of Internal Medicine that appears to question that choice. A review of the association between different types of fats and coronary (heart) disease concluded: “Current evidence does not clearly support cardiovascular guidelines that encourage high consumption of polyunsaturated fatty acids and low consumption of saturated fats.”

Translation: This study found no clear proof that cutting back on my saturated fat intake and increasing my intake of polyunsaturated fats will lower my risk for heart disease.

My first reaction was, “Yippee. I think I’ll go buy that yummy-tasting high saturated fat yogurt I usually avoid.” My second reaction was, “Maybe I need to get more information.”

Old studies, new findings

This current report is actually a review of several studies, most of which are “observational” — considered a poor source of information on the effects of dietary changes. Moreover, observational studies give us clues to what we need to study further.

And to its credit, this study also looked at real experiments on real people in randomized controlled trials.

So what’s the problem? The way I understand it, we have ample evidence that replacing saturated fats in the diet with those that are more unsaturated reduces the “bad” LDL cholesterol in our blood. And lowering LDL lowers our risk factor for heart disease.

These researchers found no positive proof, however, that just eating less saturated fat (or eating more polyunsaturated fat) will cut our risk for heart disease. Which is enough to fuel the Internet with comments like, “Don’t read anything written by food experts.”

To which I reply, I’d much rather trust a trained pilot to guide me to my destination than the guy in the back of the plane complaining about the turbulence.

So, what’s bad for your heart?

So here’s what experts generally agree on:

Trans fats — more than saturated fat — are detrimental to heart health. That’s why the FDA recommends we phase trans fats out of our food supply.

Saturated fat — of which there are several types, some more detrimental than others — complicates studies of this type even more.

Eating patterns that include a wide variety of plant-based foods — from vegetables to fruit to whole grains to beans to nuts — have shown over and over again to protect against heart disease, obesity and Type 2 diabetes. This “whole diet approach” is naturally lower in saturated fat and shows benefits “not from one specific element, but from the sum of its parts,” according to Jeremy Pearson, associate medical director of the British Medical Journal who helped fund this research.

“This study does not tell us that saturated fat is good for us,” says Pearson. “It only tells us that saturated fat may not be as damaging as we thought.”

Personally, I know the benefits when I improve the overall quality of my diet. And even if there is no absolute proof that the saturated fat in that yummy-tasting yogurt will give me heart disease, I need those extra fat calories like I need another controversial diet study.

— Barbara Quinn, The Monterey County (Calif.) Herald