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.
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.
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.
• There are several types of saturated fat - some more detrimental than others - which 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 Pear-son, associate medical director of the British Medical Journal who help-ed 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."
(Barbara Quinn is a registered dietitian and certified diabetes educator at the Community Hospital of the Monterey Peninsula.