Don’t Drink the Agave-Sweetened Kool-Aid Part II: What’s Wrong With Any High-Fructose Syrup

Who knew agaves grew in so many different flavors?

In the first post on agave nectar, I focused primarily on why it’s no more “natural” than high-fructose corn syrup, which is a delicious irony given how both sweeteners tend to be portrayed. But that isn’t necessarily a reason to avoid agave nectar. “Natural” is at best an imperfect heuristic for healthiness or environmental friendliness, and has no inherent relationship with deliciousness. But, as I also suggested in the first post, agave nectar is certainly no better health-wise than other sources of sugar, and the fact that it’s much higher in fructose than most sweeteners (70-90% vs. ~50%) gives me reason to believe it may actually be worse for your health than sucrose or HFCS-55.

So Don’t Drink the Agave-Sweetened Ketchup Either. Because That Would Be Gross.GRANOLA-WASHING

Perhaps the most baffling thing is how many people seem to think agave nectar doesn’t count as sugar. For example, the rave review of Wholemato Organic Agave Ketchup in Men’s Health, contrasts it with the “liquid candy” that is HFCS. And then implies that the even-higher-fructose agave-sweetened condiment is healthier than “fatty” butter (it’s like someone at Men’s Health was specifically trying to give me apoplectic fits): 

This ketchup forgoes the high-fructose corn syrup and uses agave nectar, preserving sweetness without clobbering your fries or hot dog with liquid candy…. Slather it on your sweet potatoes as an alternative to a fatty slab o’ butter.

Note: The review is only available on the Wholemato site because the “read more” link is broken, but I’m not inclined to think it’s a fabrication as the other links on their “buzz” page are legit and you can find nearly-identical, equally-apoplexy-inducing claims about Wholemato Ketchup at The Kitch’n, Girlawhirl, i like granola, and Well Fed Man, among others.

There are also people who claim to have given up sugar, but who still eat agave nectar. Some excerpts from the comment thread on Nicole MacDonald’s resolution to give up sugar in 2010:

Jennifer: I went sugar-free at 16 to help my psoriasis & still don’t have it, 8 years later .
I don’t miss it at all. If I want to make a cake or anything I will use agave nectar … you realise there are so many interesting & alive foods out there you can enjoy without compromising your health!! xx

Nicole: I have to admit that in the first few weeks I baked a lot using ingredients like honey, agave and brown rice syrup. Cookies are my favorite to make, and I have a long list of recipes on my blog to the right. I also drank a lot of flavored tea with honey added and that seemed to cure some of my cravings.

Beth: I stopped eating sugar last year and its worked out pretty well. As long as I can have natural sugars which are found in fruits, then I’m totally satisfied.

Not All Things That Occur Naturally In Fruit Should Be Consumed In Quantity. Like Cyanide.

Beth is certainly not alone in thinking that “sugars which are found in fruits” are healthier than other sugars. People are frequently resistant to the idea that fructose might be unhealthy because, as the name so conveniently reminds them, it’s found in fruit. Or, if they’ve been sold on the idea that HFCS is poison and fructose has something to do with that, they sometimes suggest that there must be different kinds of fructose. Take, for example, the comment by Dave on this post by ThursdaysGirl, which expressed some reservations about agave nectar:

[. . .] you say Agave is 70% fructose, ok, so that means that means a teaspoon of Agave (about 4 grams) has about 2.8 grams of fructose… Hmmm, a small tomato has about 2.6 grams of fructose in it, the same as a carrot!… so, by your ridiculous logic, you should run away from tomatoes and carrots as fast and as far as you can! OMG, never eat another tomato! And don’t even get me started on Apples!

Remember, HFCS, regardless of what the lying chemists say, is not a natural source of Fructose. It is a man made molecule. It is illegal to call High Fructose Corn Syrup “All Natural”. I wonder why… Agave can be found both All Natural and Organic!!! Small amounts of Fructose actually help metabolize Glucose better, plus its low glycemic, has natural inulin fiber which is amazingly beneficial [. . . .]

I would trust the Mayo Clinics recommendations as regards to High Fructose Corn Syrup… it is poison. But really, Apples, Carrots, Tomatoes etc all bad for you? Stop it.

It’s actually not illegal to call HFCS “natural.” The FDA has been notoriously unwilling to define “natural” aside from the essentially meaningless distinction between “artificial” and “natural” colors and flavors—which Eric Schlosser talks about extensively in Fast Food Nation (pp. 121-131). As of July 2008, HFCS is “natural” for the purposes of food labeling. You can read all about the ongoing legal debates here. However, that hasn’t stopped people from trying to differentiate “natural” fructose, like the stuff in fruit, from “chemically-produced” fructose, like the stuff in HFCS. The problem is that they can’t seem to agree which side the fructose in agave nectar is on.

As you might expect, the agavevangelists are on the side of “natural.” According to Kalyn’s Kitchen Picks :

It’s been a long time since I discovered a new product that rocked my world in the way agave nectar has done…. The sweet taste in agave nectar comes from natural fructose, the same sweetener found in fruit (not to be confused with high fructose corn syrup which has chemically produced fructose.)

On the other side, there’s Rami Nagel, whose Natural News article been widelycirculated and cited by people on both sides of the agave nectar debate. According to Nagel, agave nectar is composed of bad, man-made “fructose,” which he claims actually has a completely different chemical formula from the sugar in fruit, which he calls “levulose”:

We all know that the chemical formula for water is H2O: two hydrogens and one oxygen. The opposite would be O2H, which is nothing close to water. Likewise, man-made fructose would have to have the chemical formula changed for it to be levulose, so it is not levulose. Saying fructose is levulose is like saying that margarine is the same as butter. Refined fructose lacks amino acids, vitamins, minerals, pectin, and fiber. As a result, the body doesn’t recognize refined fructose. Levulose, on the other hand, is naturally occurring in fruits, and is not isolated but bound to other naturally occurring sugars. Unlike man-made fructose, levulose contains enzymes, vitamins, minerals, fiber, and fruit pectin. (Similar claims here and here)

However, levulose is just an alternate name for fructose. A search for “levulose” on Wikipedia automatically redirects to their fructose entry. ChemBlink claims they’re synonyms with the exact same molecular formula and structure:

levulose/fructose...not quite as catchy as tomayto/tomahto 

And even the earliest examples from the OED reveal that the terms are completely interchangeable: 

1897 Allbutt’s Syst. Med. III. 386 Cane sugar is partly left unchanged, partly converted into glucose and lævulose. 1902 Encycl. Brit. XXII. 721/1 Glucose and fructose (lævulose)the two isomeric hexases of the formula C6H12O6 which are formed on hydrolysing cane sugar.

With “levulose” eventually giving way to “fructose” by the the 1970s:

1974 Nature 10 May 194/3 Although it is true that some bacteriologists are extremely conservative in the names they use for carbohydrates, surely nobody now uses ‘levulose’…in preference to ‘fructose’ these days.

A PubMed search for “levulose” also turned up 30,398 articles about (surprise!) fructose. The twenty articles that actually had “levulose” in the title were almost all translations, mostly from German.

So no, there is no difference between “naturally occurring” and “chemically-produced” fructose (and if the fructose in HFCS is the latter, so is the fructose in agave). Nonetheless, Dave and Rami Nagel are both at least partially correct. Fructose/levulose may not contain enzymes, vitamins, minerals, fiber, and fruit pectin, but the fruits that contain levulose/fructose certainly do. And there’s no reason to believe that eating a small amount of agave nectar, say a teaspoon, with similar amounts of fiber, protein, and other nutrients as would be found in a tomato or carrot would have a different or worse effect on the body than the vegetables themselves.

Fructose and Your Liver

Just because fructose isn’t necessarily bad for you in the amounts present in most fruits and vegetables, that doesn’t mean it’s a healthier substitution for other sugars. The evidence from studies on humans is still pretty scant. However, in a 2008 study where 23 subjects got 25% of their caloric intake from either fructose-sweetened or glucose-sweetened beverages for 10 weeks, the subjects who drank the fructose-sweetened drinks showed signs of decreased insulin sensitivity (a sign of diabetes) and increased fat in their abdominal regions, especially around their heart and liver, which is associated with cardiovascular disease (here’s the study itself or a translation from WebMD).

We’ve known for over 50 years that fructose is metabolized differently than glucose. Once it enters the body, it’s taken up by the liver, so it doesn’t raise blood sugar levels as much as glucose. It bypasses the step that insulin regulates, so diabetics can digest fructose about as well as non-diabetics. Which initially sounds good, especially for diabetics; however, more recently, fructose has been shown to have the same effects as alcohol on the liver:

I won't pretend to understand everything that's going on here, except that it illustrates the various processes and feedback mechanisms that cause fatty liver disease. From “Fructose Takes a Toll” in the August 2009 Hepatology (login required)

As a recent article in Physiological Review notes:

Fructose was initially thought to be advisable for patients with diabetes due to its low glycemic index. However, chronically high consumption of fructose in rodents leads to hepatic and extrahepatic insulin resistance, obesity, type 2 diabetes mellitus, and high blood pressure. The evidence is less compelling in humans, but high fructose intake has indeed been shown to cause dyslipidemia and to impair hepatic insulin sensitivity.

So while probably harmless in small amounts, it’s certainly not a “healthy” sugar or a free pass to eat sweet things without potential/likely health consequences.

I’ll do a follow-up eventually about the claim that you can use less of it because it’s sweeter. There are lots of conflicting claims about how much sweeter it is and how much less of it you use that I’m still trying to sort out. So far, I’m not at all convinced that the small caloric benefit is a reasonable trade-off for the risks of increased fructose consumption. I’ll also address one final defense: at least in some applications and to some palates, agave nectar may taste better. I admit to being a little skeptical, but a friend has promised to arrange a blind taste-test of mint juleps made with agave nectar, simple syrup, and a 50-50 agave nectar/brown rice syrup blend. That won’t happen until the national day of mint julep drinking, which falls on May 1, 2010 this year. So, until then, I’m going to take a little break from reading and writing about agave nectar.