Background
There is a widely known passage in one of Peat's articles on the actual energy content of high fructose corn syrup-(HFCS)-containing beverages. This passage is often used by peatarians to explain the weight gain seen in populations with high HFCS-soda consumption and serves as a basis to prefer sucrose-sugared products compared to HFCS-products (such as mexican coke vs. US-american regular coke)."Much of the current concern about the dangers of fructose is focussed on the cornstarch-derived high fructose corn syrup, HFCS. Many studies assume that its composition is nearly all fructose and glucose. However, Wahjudi, et al. (2010) analyzed samples of it before and after hydrolyzing it in acid, to break down other carbohydrates present in it. They found that the carbohydrate content was several times higher than the listed values. "The underestimation of carbohydrate content in beverages may be a contributing factor in the development of obesity in children," and it's especially interesting that so much of it is present in the form of starch-like materials." - Ray Peat in Sugar Issues
Relevant studies
The study referenced by Peat was a conference abstract, not a full article. Conference abstracts are in most cases not peer-reviewed and submitted at stages were your whole study is not finished yet (because you have to submit those often half a year earlier). This year, a full article was published by White et al. that tried to validate these findings by also analyzing the carbohydrate content in HFCS sodas. They concluded the following:"Total sugars content of commercial beverages is consistent with common industry practices for canned and bottled products and met the US Federal requirements for nutritional labeling and nutrient claims. Prior concerns about composition were likely owing to use of improper and unverified methodology".In their article, they also critcized the conference abstract by Wahjudi et al. I took this as a basis to personally contact the senior author of the Wahjudi study, Dr. Paul Lee. He wrote me the following in response:
"White is right about our abstract. We were not able to repeat the observations, and found out that the calibration samples were not properly prepared leading to systematic errors. "On the question about whether mexican or US-american regular coke is better, the following things are interesting to know:
- Mexican coke ingredients: Carbonated water, sugar, caramel color, phosphoric acid, natural flavors, caffeine (150 calories in 355ml)
- Regular coke ingredients: Carbonated water, high fructose corn syrup, caramel color, phosphoric acid, natural flavors, caffeine (140 calories in 355ml)
- In an interesting study, people consumed regular or mexicon coke in a blinded or non-blinded fashion (knowing what they drank or not and switching the container). It showed that when people don't know the content and just go by taste, people actually prefer the regular US-american and not the mexican coke. When there was a preference for mexican coke, it could better be explained by the preference of drinking out of a glass bottle vs. an aluminium bottle or by psychological perception, when the subjects were told they were drinking mexican coke (even though they actually got regular coke). This study emphasizes the decisive role of the mind when it comes to perception of foods.
Conclusions
The widely cited result by Wahjudi et al. is based on a systematic error. HFCS beverages don't contain more calories than listed on the labels. Given the wide range of studies showing that HFCS is practically identical in metabolic behaviour compared to sucrose, any adverse or beneficial effects seen in studies using HFCS as a calorie source would likely also be seen with the same amount of sucrose.Mexican coke even contains slightly more calories than regular US-american coke. So all in all, you might just as well save the extra money and drink regular coke from a mexicoke glass container.
