THE NEW FAT REVOLUTION

 

“We shouldn’t be thinking about fat at all.  It’s about the overall quality of the food you eat.”

 

We’ve been obsessed with fat for more than half a century.  And this past spring, the fervor hit a new level.    As a result, a lot of questioning hands shot up in the air.  Yours was likely one of them.

 

That feeling of being nutritionally adrift is understandable.  After all, our aversion to fatty foods is as ingrained as the advice to get 8 hours of sleep a night and to regularly exercise.  It all started back in the 1950s, when scientist Ancel Keys made headlines by discovering that saturated fat raised cholesterol levels.  The idea of eating low-fat took off.  Then, about 15 years ago, the concept of ‘good’ and ‘bad’ fats was introduced.   We were told to watch saturated fat, and then trans-fat joined the no-no list a few years later.   We were to embrace unsaturated fats like nuts, oils, and avocados.  So, when a recent study (Annals of Internal Medicine) concluded that saturated fat does not appear to increase heart disease risk, our collective jaws hit the floor.    The researchers analyzed data from 76 studies involving more than 600,000 people and found that those who ate the most of the so-called ‘bad’ fat did not have a higher risk of cardiovascular disease than those who ate the least.  (Trans-fats remain a villain: in the study they were associated with a higher risk.)

 

So, should we end the war on fat?  First, one myth about the Annals study must be dispelled: despite news headlines, no one is saying that all saturated fat is healthy.  Lack of harm is not the same thing as being beneficial.   Overall the findings throughout the literature are that saturated fat is on average neutral compared to everything else we eat; it doesn’t seem to affect heart disease risk.   Initially science was just focused on LDL cholesterol, and the data showed that saturated fat indeed raises LDL levels.  That’s all the evidence we had.  But nutrition science, which isn’t even 100 years old, has rapidly advanced, and the data have changed.   It’s true that saturated fat raises LDL cholesterol; that finding from the 1950’s studies holds up.  But what researchers have discovered since then is that saturated fat also raises HDL, the ‘good’ cholesterol.  And saturated fat does not increase the number of LDL particles, one of the most powerful predictors of cardiovascular risk.  Saturated fat makes LDL particles larger and that’s pretty benign in terms of cardiovascular disease.

 

It’s worth noting, too, that this isn’t some newfangled theory.  Evidence that saturated fat may not raise heart disease risk has been in the literature for decades.  It’s just that 2014 happened to be the year it went viral.  To be sure, the issue is still being studied, and debated.  Not everyone agrees on the degree to which saturated fat impacts our health.  But for now, the bottom line appears to be this: We’ve evolved our thinking and the ‘good’ and ‘bad’ stuff has to go.   Let’s think in terms of beneficial and not-so-great.  There is no bad, except for trans-fats (partially hydrogenated oils).

 

The Annals study also sparked a serious conversation about another health issue at play: what replaced the fat in our diets when we banished it.  We started eating more concentrated sweets and processed carbohydrate.  We replaced one thing with something worse.  These types of refined carbohydrates do lower LDLs, but they also lower HDL levels and increase triglycerides (a type of fat in your blood).  Triglycerides are also linked to higher blood glucose levels and weight gain.  So we’re not just talking about an increased risk of heart disease but also obesity and diabetes.  This may be part of the reason why the group in the Annals study who ate the least saturated fat didn’t have lower rates of cardiovascular disease than those who ate loads of it, because they were subbing in unhealthy processed carbohydrates. It also helps explain why, despite the fact that we’ve lowered our saturated fat intake over the past several decades, obesity rates have continued to climb and heart disease in still our number-one killer.  What the study tells us is that there is more than one way to eat badly!

 

So what, exactly, should we be eating, given all this new evidence?   A diet that’s almost forehead-smacking simple, and what most experts agree on, not matter where they fall on the saturated-fat issue: eat a diet rich in a variety of vegetables, nuts, fruits, seeds, some healthy protein like fish, poultry or beans, and minimally-processed, whole grain carbohydrates (the kind that are high in fiber and have been fiddled with the least, like black rice and Ezekiel bread products).  Also key: limiting concentrated carbohydrates like white bread and processed foods like cereal and most store-bought baked goods.  If the food has unpronounceable ingredients and a long shelf life, keep walking.  (Any of this sound familiar?)  And fats?  How should we think about those?  For the record, our Dietary Guidelines recommend limiting saturated fat to no more than 10 percent of total daily calories, and instead emphasizing foods containing unsaturated fat.  Eating more of these genuinely healthy fats is advice worth following, but some experts have a different take: It’s about the overall quality of the foods you eat.  Depending on the foods you choose, you can eat a low-fat diet that’s terribly unhealthy and raises your heart disease risk, and you can eat a high-fat diet that does the same, or you can eat very healthy versions of either.

 

We’re getting too hung up on grams and percentages and what we really should do is take a big-picture view of eating.  Foods are complicated.  We can’t just look at one aspect and judge their overall healthfulness.  It’s time to stop focusing on macronutrients (carbohydrate, fat and protein) and think in terms of what should make up the majority of your diet.  If you do that, you can’t go too far wrong.

 

Shaun Driesbach

 

**For more information related to this article, please see the September issue of the newsletter, and other related articles on the website.  Thank you.