Tomorrow's health-care summit may well devolve into bad theater, but one of the few areas of agreement at its start will be bipartisan support for employers and the government to get in on the promotion of prevention and wellness. 

"Promoting better health and preventive care is one area of real common ground," wrote David Herszenhorn in a New York Times preview on Sunday. "Various proposals call for grants to help employers start programs, including nutrition counseling, preventive tests and fitness."

Conservatives hear the word prevention and break out in song at the sight of their old friend — individual responsibility! The health system needs to stopping paying for everyone's medical bills, the thinking likely goes, and start offering information — like the importance of Keeping Your Cholesterol in Check. Likewise, progressives surely sense something appealingly holistic in promoting health instead of just treating sickness — of eschewing an "unhealthy diet" instead of simply waiting to cut out its residue from your plumbing. Reps. John Boehner and Steny Hoyer may not agree on much, but I bet they both reach for skim when walking through Capitol Hill cafeteria line.

Neither of these motivations for promoting wellness are bad in themselves. But few of the canny political animals who make up the bipartisan embrace of prevention seem to recognize the politics that have shaped and at times distorted prevention science.  As a result, any bipartisan prevention effort to emerge from the current health care debate will likely would march forward with fallacious, expensive, and even dangerous recommendations about diet and health — or at least when it comes to subjects like "bad cholesterol" or what makes for a healthy diet. 

A sweeping meta-analysis
That's if you are willing to consider the work of University of California Berkeley lipid scientist Ronald Krauss, anyway. Last month, Krauss published the results of a sweeping meta-analysis on the effects of saturated fat in the diet. 

The article, which was published in the American Journal of Clinical Nutrition, abstract available here, pooled 21 epidemiological studies, prospective research which followed, get this, 347,000 subjects. It found that "there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of coronary heart disease or cardiovascular disease." In other words, he found no evidence for the decades-long, impenetrable orthodox prevention message of our need to reduce saturated fat in the diet in order to reduce our risk of heart disease.

We will now pause for those of you choosing to mark the announcement with an extra pour of half-and-half into their coffee.

Krauss is no gadfly on the fringe of nutrition science. He is a widely respected lipid scientist and recipient of NIH funding who is assigned for the next seating of the National Cholesterol Education Panel, the influential governmental body that  determines formal recommendations for acceptable levels of cholesterol. He is also a relentlessly determined basic scientist, albeit one who works in a field — the interaction of blood lipids, diet and heart disease — that frequently seems more interested in presenting a unified prevention message than in furthering our understanding of the remarkable complexity of human physiology. 

So, you ask: How can saturated fat be harmless? (When it comes to heart disease, that is — it is, of course, still high in calories.) 

LDL: A disparate array of particles
The answer comes down to the diversity of LDL. For years, it has been an easier sell to label LDL cholesterol as one big bad thing — "the bad fat." But researchers have always known that LDL is, in fact, a disparate array of particles, and thanks to early work by Krauss and others, they have long known that different forms of LDL react differently to foods in the diet and in relationship to heart disease. Small LDL is bad stuff, largely because it tends to rise in concert with the lowering of HDL. Small LDL, moreover, rises due to an elevation in triglycerides brought on by carbohydrates in the diet.

While saturated fat does indeed raise LDL cholesterol, and high levels of LDL cholesterol are  associated with an elevated risk of developing heart disease, lost in the simplification of that message was the fact that saturated fat from dairy only raises large, fluffy forms of LDL — forms Krauss has determined are largely benign. (Krauss has received funding from the dairy industry. That would seem like a deal  breaker, but this appears to be a case of a wrongly maligned industry that was smart enough to fund the right researcher. He has not yet exonerated saturated fat from animals, but his recent meta-analysis would appear to do so.)

Boiled down, Krauss' message has been that excessive carbohydrates in the diet — probably refined carbohydrates in particular, but he has no data yet on that question — are the true culprit behind heart disease. As carbohydrate intake goes up, people can develop a blood lipid phenotype in which they have both low HDL and a high number of small forms of LDL, the subparticle of LDL known to be associated with heart disease. Krauss believes the low-fat prevention message exacerbated this process, and you only need to look at the double-barreled sight of a "low fat muffin" in a chain coffee store to see its proxy in the food supply. 

For a lengthier review of these issues, please see "Your Unstoppable Heart" in last month's Men's Health. (Written by yours truly, but don't hold that against me.)

Questioning the cornerstones
What does this mean for the bipartisan zeal for prevention? Consider this: Two cornerstones of our prevention superstructure — LDL is bad, and saturated fat is bad — may be not only ineffective, but contributing to new health problems in our society.

Reducing saturated fat in the diet may be leading us to consume more carbohydrates, thereby increasing our risk of heart disease. The widespread use of lipid controlling medications, moreover — paid for with tax dollars, for the most part — and increasingly aggressive guidelines for lowering LDL may be an expensive, unwarranted distraction from better markers of heart health — like HDL.

Freelancer Paul Scott of Rochester writes frequently about health and fitness for various media. Susan Perry will return March 8.