In retrospect, this probably could have been an entirely separate article in the "things that won't kill you" series, as many people still believe that dietary cholesterol (i.e. cholesterol in food) is a bad thing. For example, the article that image was taken from claims:

If you get too much dietary cholesterol (over 300mg a day) the extra cholesterol will accumulate in the walls of the blood vessels, making your LDL (bad) blood cholesterol levels rise. Over time, your arteries will become narrower, which can cut off the blood supply to your heart (causing a heart attack), or your brain (causing a stroke).

However, that's pretty easily dismissed—even Ancel Keys, "Monsieur Cholesterol" himself, never argued that dietary cholesterol was related to serum cholesterol or heart disease. In a 1952 article in Circulation, the journal of the American Heart Association, Keys noted that although rabbits and chickens that eat high-cholesterol diets will develop high cholesterol and atherosclerosis, or hardening of the arteries:

No animal species close to man in metabolic habitus has been shown to be susceptible to the induction of atherosclerosis by cholesterol feeding…. Moreover, even in the favorite species for such  experimentation, the herbivorous rabbit, the necessary concentration of cholesterol in the diet is fantastically high in comparison with actual human diets. Moreover, there is reason to believe that man has a greater power of cholesterol regulation than does the rabbit or the chicken. From the animal experiments alone the most reasonable conclusion would be that the cholesterol content of human diets is unimportant in human atherosclerosis.

Two "moreovers" in one paragraph, people! “Most reasonable conclusion”! Moreover, five decades of subsequent research haven't given anyone any reason to think differently. In 1997, Keys was even more direct:

There’s no connection whatsoever between cholesterol in food and cholesterol in blood. And we’ve known that all along. Cholesterol in the diet doesn’t matter unless you happen to be a chicken or a rabbit.

Research done in the interim on the relationship between diet and heart disease in humans like the Framingham and Tecumseh studies showed no relationship between cholesterol consumption and blood cholesterol or heart disease. I'm not even going to modify this with "probably" or "as far as we know": There is no reason to believe that how much cholesterol you eat has any effect on your health.

But that doesn’t stop the AHA from recommending that “most people…limit cholesterol intake to less than 300 mg per day” and claiming that “an egg can fit within heart-healthy guidelines for those people only if cholesterol from other sources — such as meats, poultry and dairy products — is limited.” Despite repeated studies showing that egg consumption is not associated with higher serum cholesterol, myocardial infarction, cardiovascular disease, or all-cause mortality.Read more

This is probably going to be an even harder sell than MSG, but I swear I'm not just trying to be contrary. It's true that all the major sources of public health and nutrition advice, including the Harvard School of Public Health, Mayo Clinic, CDC, and American Heart Association continue to refer to saturated fats as "bad fats" and suggest that people avoid them as much as possible, limit them to <7-8% of their total caloric intake, and replace them with "good," i.e. unsaturated fats, whenever possible. It's also true that there are a few studies that suggest that increased saturated fat consumption is correlated (albeit weakly) with cardiovascular disease (CVD).

However, many other studies have found no increase in CVD associated with saturated fat consumption. And several recent review articles have concluded that the evidence for a connection between saturated fat consumption and CVD is inconsistent, insufficient or nonexistent.

There are basically three things that have convinced me that saturated fat isn't independently responsible for heart disease or death:

1) groups of people who eat vastly more saturated fat than most Americans frequently have lower rates of CVD—or no apparent CVD at all

2) the study that first inspired many people to think saturated fat was a bad thing had a lot of obvious flaws and has been thoroughly discredited

3) there's no good evidence that the proposed mechanism actually works—briefly: saturated fat supposedly causes heart disease by raising serum cholesterol levels because cholesterol is what clogs arteries and causes heart attacks and strokes, but serum cholesterol turns out to be a really poor predictor of CVD 

1) The French (and Polynesian and Melanesian and Masai and Fulani and Sri Lankan) Paradox 

The most confounding phenomenon for the theory that saturated fat consumption causes heart disease (sometimes called the lipid hypothesis or lipid-heart hypothesis or diet-heart hypothesis) is the virtual non-existence of CVD in multiple populations that eat way more saturated fat than most Americans. This has primarily been documented in the Pacific islands where coconuts, which are very high in saturated fat, are a staple food. For example, before the 1970s, the inhabitants of the island Tokelau got an estimated 55% of their calories from saturated fat, but heart disease was virtually unknown (according to Gary Taubes and Stephen Guyenet; notably, since their diet has shifted to include less saturated fat but more sugars and refined carbohydrates, many health indicators have worsened). Read more

Confession: I not only avoided high-fructose corn syrup (hfcs) until about a year ago, I was actually skittish about fresh corn for a while after my first encounter with Michael Pollan in The New York Times Magazine (or it might have been this article). I stopped eating corn tortillas and frozen corn kernels and felt vaguely panicky about the possibility that I was consuming hfcs in condiments and sandwich bread when I ate out, even if it would have only been tiny amounts.

Now that I'm over it, I sometimes have a hard time remembering what was so scary about the idea that there was corn in everything I was eating, an idea that was obviously ludicrous anyway because I was a vegetarian who mostly ate food prepared at home from whole, fresh, non-corn ingredients. But looking back at the articles linked above, they are pretty ominous. Even though Pollan notes that a corn-based diet has been the norm in Mexico for centuries without any apparent ill effects, and the story he tells about the "cornification" of the American diet is too complex to be a nefarious plot designed to kill us all, it's clear that he thinks the amount of corn Americans eat on average is a Bad Thing. Sure, it may rely on innocent accidents of nature, like the uniquely efficient way corn fixes carbon during photosynthesis and and the great distance corn pollen has to travel to reach the style, but it's also reliant on much more insidious developments: synthetic pesticides and fertilizers, an arcane federal farm subsidy systems that turned corn into "a welfare queen," agribusiness giants with seed patents on genetically-modified strains, giant livestock feeding operations that use antibiotics to keep cows alive because eating corn makes them sick, and food manufacturers who profit from getting people to buy cheap food in ever-increasing quantities. Eating corn in any form may seem like a way of giving in to all of that or even supporting it.

So although I did a fair bit of eye-rolling when I read about people avoiding sweet corn at their farmer's markets this summer or feeling "corn guilt" when they eat popcorn, it's worth remembering that I was one of them not so long ago.

HFCS paranoia is not primarily an issue of ethical consumption

It's not that many of those concerns are invalid—it's true that most corn relies on a lot of synthetic fertilizers and pesticides, that much of it is grown using genetically modified seeds with patents held by huge corporations that have been known to sue farmers when corn with their patented genes end up in their fields, that cows fed diets of corn get sick and are more susceptible to diseases like e coli that can threaten humans. But it's also far from clear that refusing to eat ketchup containing high fructose corn syrup is an effective means of changing any of that or even primarily motivated by the desire to change those things.

Although people like Pollan have made a big deal about corn sweeteners being artificially cheap due to farm subsidies, the actual farm cost of hfcs in the food products we buy is so minimal that even if subsidies were eliminated entirely, it might not affect portion sizes or consumer demand at all. Even in soft drinks, which are by far the most demonized hfcs delivery system, hfcs represents just 3.5% of the total cost of manufacturing. The corn content, the only part actually affected by farm subsidies, is only 1.6 percent of the price (based on US Department of Commerce data). A comparison between the U.S., Australia, the UK, and France, all of which have different sugar policies but similar consumer prices, show no pattern in the relationships between how cheap sugar is, how much of it people eat, or how fat on average they are (which most people wrongly assume is a reliable measure of health outcomes, but I'll tackle some other time).

Pollan's formal case against hfcs relies primarily on arguments about price and prevalence, but that doesn't really explain the kind of paranoia his books and articles have helped inspire about eating corn and/or hfcs. Not buying and eating something because it's too cheap just isn't the kind of consumer behavior that spreads the way hfcs-phobia has. Nor is this some sort of mass avoidance of all added or refined sugars, or brands like Snapple and Pepsi wouldn't be running huge campaigns to advertise soft drinks containing only "natural sugar."

Instead, people have latched on to the implication, which isn't supported by any data I can find, that hfcs is nutritionally worse than other sugars. The hfcs paranoia isn't caused by the idea that hfcs might be unwisely or unfairly subsidized or that pesticides used to produce corn are poisoning waterways or anything related to feeding corn to cows. The fear is that hfcs might be some kind of demon poison that makes people fat.

The confusing part: "high fructose" isn't actually high fructose

The idea that hfcs is worse than other sugars seems to be primarily reinforced by research about how fructose is metabolized. Just last April, an article about a study comparing drinks sweetened with fructose and  glucose in the New York Times began:

Some research has suggested that consumption of high-fructose corn syrup, used as a sweetener in a wide variety of foods, may increase the risk of obesity and heart disease. Now, a controlled and randomized study has found that drinks sweetened with fructose led to higher blood levels of L.D.L, or "bad" cholesterol, and triglycerides in overweight test subjects, while drinks sweetened with another sugar, glucose, did not.

Things like this get reported all the time. However, the very last sentence of the article quotes another biochemist:

The study did not test high-fructose corn syrup, he said, and judgments should not be made about it from the findings.

Not that that stopped the author from leading with the useless, ambiguous claim about a supposed link between hfcs and obesity, but surely this deserves a little more attention: yes, fructose alone seems to cause more insulin resistance and weight gain in both rats and people than glucose alone. But high fructose corn syrup is only "high fructose" relative to normal corn syrup, which is 100% glucose.

The kind of hfcs used in most food processing, including soft drinks, is hfcs-55, which is approximately 55% fructose and 45% glucose, or almost identical to sucrose, which is about 50/50. Another kind, hfcs-42, is used in the manufacture of some baked goods, and if fructose is really worse, that would make that kind of hfcs healthier than cane sugar. Indeed, studies comparing the consumption of hfcs to sucrose have shown no differences in metabolic responses (or energy or macronutrient intake) at all.

The argument that hfcs is somehow responsible for the obesity epidemic relies entirely on correlations between the rise of hfcs in food manufacturing in the 1980s and the rise in national rates of overweight/obesity (and the exponential rise in concern about fatness). Pollan's case against hfcs amounts to a gut suspicion that:

It's probably no coincidence that the wholesale switch to corn sweeteners in the 1980's marks the beginning of the epidemic of obesity and Type 2 diabetes in this country.

Of course, this fails to account for the simultaneous increases in obesity in many other countries, perhaps most notably Australia, where obesity rates rival or even exceed those in the U.S., but sugar is the primary sweetener. It's not that he's totally wrong; it does seem probable that U.S. farm subsidies and the cheap price of highly-palatable, nutrient-poor, calorie-rich, primarily carbohydrate-based foods is one factor driving the relatively small increases in the average American's weight since the 1970s. And the history of corn cultivation and agricultural policy has something to do with that. But there's no reason to think that hfcs is uniquely responsible for the "obesity epidemic." After all, if it weren't for subsidies and tariffs that keep the price of sugar artificially inflated, which are the result of a different set of biological, historical, and political contingencies, it would be just as cheap. 

Ultimately, hfcs is just another source of sugar, nutritionally no different from cane sugar, and way better than agave nectar if you're concerned about fructose. It might be slightly worse than things like honey (esp. raw) and maple syrup (esp. grade B or lower) if you're interested in vitamins and minerals. (This is all assuming the hfcs in question contains mercury, but that's sort of another story altogether).

That doesn't mean hfcs is  "natural," a word which has virtually no meaning when it comes to food labeling anyhow, but then, if "natural" is the alternative to "processed," no sweeteners are. Agave nectar must be filtered, hydrolyzed, re-filtered, and concentrated before it can be used as a sweetener. Refined cane sugar is purified with phosphoric acid and calcium hydroxide, and sometimes whitened using bone char which is why some vegetarians and vegans refuse to eat it.

The upshot is there's no reason to believe that hfcs is any worse for you than sugar or much worse for you than any other sweeteners, and there's certainly no reason to believe that a little bit here and there in a favorite condiment or even the occasional soda is going to hurt you.

Later in this series: I've gotten a request to weigh in on fruit juice, and will try to do that soon. And someday I'll get around to msg, as promised before.