winning the war on fructose

I just mentioned the quasi-voluntary move by the American Beverage Association to stop selling corn-syrup-laden beverages in schools. Peter's response in comments deserves a post of its own.

Actually, high fructose corn syrup has been shown to chemically affect the brain such that the brains of the consumers of this substance are effectively made incapable of regulating their intake of food. If we are going to take obesity seriously as a legitimate public health problem and we are going to be consistent with our regulation of addictive chemicals that have a detrimental effect on the physiology of the individuals consuming them (to the benefit of those companies selling them), then fighting the schoolyard distribution of these substances is what we have to do.

I'll address each contention in turn.

1. "Actually, high fructose corn syrup has been shown to chemically affect the brain such that the brains of the consumers of this substance are effectively made incapable of regulating their intake of food."

That's just a tad overstated. HFCS, even though it appears to affect metabolism and leptin production differently than sucrose, has not been shown to be uniquely harmful. The Bray paper makes no attempt to experimentally confirm the contention, relying instead on historical correlations and inferences from animal experiments. Second, the best-designed study to date points to sucrose as a weight-gain culprit, as the Bray paper notes.

Ludwig et al (31) showed that in adolescents participating in the Planet Health project, the quantity of sugar-sweetened beverages ingested predicted initial body mass index (BMI; in kg/m2) and gain in BMI during the follow-up period. Raben et al (32) designed a randomized, double-blind study to compare the effect of calorically sweetened beverages with that of diet drinks on weight gain in moderately overweight men and women. This European study found that drinking calorically sweetened beverages resulted in greater weight gain over the 10-wk study than did drinking diet drinks. Compared with the subjects who consumed diet drinks, those who consumed calorically sweetened beverages did not compensate for this consumption by reducing the intake of other beverages and foods and thus gained weight. The beverages in this study were sweetened with sucrose, whereas in the United States almost all calorically sweetened beverages are sweetened with HFCS. Thus, we need a second randomized controlled study that compares sucrose- and HFCS-sweetened beverages. This could establish whether the form of the caloric sweetener played a role in the weight gain observed in the study by Raben et al .

I'd wager that it's the mode of consumption, not the precise chemical substrate, that makes the greatest difference. Liquids are easy to consume, sliding down the gullet without pause or effort. Calorie-rich liquids (and fruit juice is a culprit here, too) don't expand in the stomach like other starches, and don't produce a feeling of "fullness" unless taken in massive quantities. At any rate, more study is needed.

Responding to the Bray paper, Michael Jacobsen doubts that HCFS is to blame:

[C]aloric soft drinks' contribution to obesity is not likely to have been due to HFCS, but to other factors that increased consumption, including the following: 1) massive soft-drink advertising campaigns (about $6 billion over the past decade), 2) serving sizes that have increased over the years from 6.5-ounce (192 mL) bottles to 12-ounce (355 mL) cans to 20-ounce (591 mL) bottles and to 64-ounce (1893 mL) cups at some locations, 3) soft drinks having become a child's standard drink at increasingly patronized fast-food restaurants (which sometimes offer free refills), 4) huge servings offered at cinemas and convenience stores, and 5) ubiquitous soft-drink vending machines (including in schools).

(And note that the last factor, soda in schools, is but one of five variables.)

Despite this, we can concede the inarguable point that sugary sodas aren't healthy in large doses. What, then, should we do?

"If we are going to take obesity seriously as a legitimate public health problem...."

We should. (As an aside, adenoviruses might play a role in the obesity "epidemic.")

...and we are going to be consistent with our regulation of addictive chemicals that have a detrimental effect on the physiology of the individuals consuming them (to the benefit of those companies selling them)...

1. It may alter metabolism, but HFCS's status as an "addictive" substance is entirely speculative and unwarranted.
2. We aren't consistent in our regulation of addictive chemicals, anyhow.
3. All unhealthy chemicals aren't created equal, and perhaps inconsistency is a good thing. Consider all the factors listed by Jacobsen, and take a look at this unscientific list of HFCS-saturated foods. Impressive or frightening, depending on your sweet tooth.
4. The "detrimental" nature of sugary soda can be largely offset by moderation--which, as this intriguing study demonstrates, comes from a little education.

At 12 months the mean percentage of overweight and obese children increased in the control clusters by 7.5%, compared with a decrease in the intervention group of 0.2% (mean difference 7.7%, 2.2% to 13.1%; fig 2).

...then fighting the schoolyard distribution of these substances is what we have to do.

If we grant every previous premise, does this mean banning soda in all schools, even high schools, where--presumably--students are old enough to make their own dietary choices, and where soft drink revenues fund sports and activities? When limited sizes (12 instead of 20 ounces) might be a workable compromise at that level? When the ban won't affect the other poison drinks, fruit juices, so its efficacy might be mitigated from the outset? When soda is already nonexistent in elementary schools? And when parental behavior is hugely influential on children's dietary choices, as milk commercials constantly remind us?

If the ABA (the other ABA) wants to fold to outside pressure, okay. But if the problem is much broader than vending machines, and is the consequence, not the cause, of cultural largesse, then this new proposal will have all the flavor and fizz of Diet Rite.