For years, we’ve been led to believe that fat is the enemy—but new research indicates that maybe we’ve got it all wrong.

That’s the tricky thing about research: it’s always evolving. And although the research continues to evolve, the guidelines often do not. Back in the early 1990s, saturated fats were identified as a culprit in heart disease. The result was a drastic shift toward fat-free food. Admit it—you probably bought your fair share of fat-free cookies, fat-free bagels, and fat-free cream cheese.

But what happened when we shunned fat? We had to replace that fat with something and we did: sugar and carbohydrates. Of course, now we know that a high intake of sugar and carbohydrates is associated with a whole bunch of health risks, too.

Here’s the irony: it’s all a great big experiment. No one can say for certain that a food—or a component of food, such as saturated fat—is good or bad. We study the effects of these things and we draw conclusions—sometimes before we have all of the information.

That could be what happened with saturated fat. The problem with saturated fat began with research in the 1960s that showed that saturated fat increased LDL cholesterol (the “bad” cholesterol). Researchers then drew the conclusion—really, the assumption—that saturated fat increased the risk of heart disease. Here’s the thing, though—over the years, the research just has not supported this theory.

In fact, the results of a recently published landmark study suggest that saturated fat isn’t the enemy we’ve made it out to be. The study included data from 530,525 people. After analyzing fat intake, the researchers found no association between saturated fat intake and heart disease. Yes, you read that right—no association. The relative risk of heart disease was no different among people with a high intake of saturated fat and those with a low intake of saturated fat. What’s more, in examining other types of fat, they found that trans-fats may increase the risk of heart problems and monounsaturated fats and omega-3 fats did not appear to provide a heart benefit.

Why the discrepancy? Well, it could be because we know more about the relationship between cholesterol and heart disease than we did 30 or 40 years ago. We used to think that LDL cholesterol was a predictor of risk—but now we know that the ratio of LDL to HDL (the “good” cholesterol) is more important. And irony of all ironies—saturated fat may actually help increase HDL cholesterol.

The bottom line: things are never as black and white as we would like to think. Cutting out entire food groups—no fat, no carb, or whatever the latest fad is—is never a good idea. Instead, aim for moderation. This recent research is probably not a hall pass to consume copious amounts of bacon. Instead, the takeaway message might be as simple as this: eat a variety of real foods in moderation.

Reference:
Chowdhury R, Warnakula S, Kunutsor S, et al: Association of Dietary, Circulating, and Supplement Fatty Acids With Coronary Risk: A Systematic Review and Meta-analysis. Annals of Internal Medicine. 2014;160(6):398-406.