The ever growing focus on industry influence on the scientific method certainly fits the modern focus distrusting anything associated with big business. I am far from totally okay with how much money plays into politics nowadays, and Capitalism + Science isn't a love story for the ages. However, I believe, in science, we should be thorough in calling out all biases, and not let our own concern around industry funding transform into its own bias.
I have long followed Marion Nestle's Food Politics - see here - and have always enjoyed her commentary on the food industry, though I often find myself seeking out the reasoning of the alternative position without blindly following her opinions. One of her recent posts on "Guess Who Funded the Study" was particularly problematic to me.
You can find the post here. Dr. Nestle notes that two conflicting studies came out about the relative content of fructose in drinks -if you're interested in the fructose debate, I encourage you to read David Despain's blog post-interview with John Sievenpiper - see here. The first study was funded by NIH (1), and followed up on a study by Ventura et al (2) that found the mean fructose content of High Fructose Corn Syrup (HFCS)- sweetened beverages to be higher than the 55% that the Corn Refiner's Association reports - see here. The other study, entirely funded by the International Society of Beverage Technologists (ISBT), and authored by Dr. John White, previously known for defending HFCS's similarity to sucrose (4), found that the fructose content of HFCS sweetened beverages randomly obtained from retail store shelves was concordant with the commonly accepted 55% fructose proportions.
Dr. Nestle doesn't go into the methodologies of the study but states that "Really, these kinds of results are so predictable that all I have to do is see the results to guess who must have funded the study. Coincidence? I don’t think so."
Is there something dubious about the ISBT study? There's a couple important issues here related to different methodologies:
As noted in the discussion portion NIH study, the original LC data was limited because it didn't include maltose in their measurements - maltose being a disaccharide of glucose could effect the relative Fructose:Glucose. In table 1:formulas , we can see a major limitation: total sugar was measured as sucrose + lactose + maltose + galactose + fructose + galactose. Looking back at the Corn Refiner's site, HFCS is composed of 55 percent fructose, 42% glucose and 3% sugars and other polysaccharides. As noted in the ISBT study introduction, the remaining 3% is composed of maltose, maltotriose, maltotetraose and higher polysaccharides - all polymers of glucose. The NIH study appears to have missed out on measuring these, skewing the relative ratios to appearing to have higher fructose contents.
The ISBT measured fructose, glucose, and these other polysaccharides (refers to them as DP2+) in 80 samples randomly pulled from retail store shelves. The measurement was taken by two independent laboratories that verified the separation and detection methodology and precision, using the accepted ISBT protocol. The authors go on to note that there are limitations to gas chromatography with acid catalysis, which can degrade oligosaccharides but also degrades fragile sugars, which has limited other (unpublished) attempts to report that HFCS contained more carbohydrate than listed (5). White even goes a bit further to suggest that the Ventura et al 's concerns regarding sucrose in their previous findings (2) were a failure to consider acid-catalyzed sucrose inversion to free fructose and glucose that readily occurs in the low-pH environment of carbonated drinks, and that this concern "appears to based on incomplete understanding of sugars chemistry in carbonated beverages" - Oy.
For more on the analyses used for measuring saccharides, the corn refiners association openly lists their protocols: http://www.corn.org/publications/industry-resources/analytical-methods/analytical-methods-toc/
Sometimes, industry association leads to a biased study. Other times, industry means that they are the experts and have hired the best scientists to determine the best methodologies to produce the products they state. Industry being involved with a study should not automatically mean that its results are to be discredited. I'm no analytical chemistry expert as it applies to sugar (I've used HPLC in relation to amino acids in breastmilk), and not many are. Those who are are employed by the CRA and ISBT to figure this stuff out. It's one thing to ask questions about methodology and ask for transparency, it's another to accuse an entire industry of funneling more fructose into the food supply.
1. http://www.sciencedirect.com/science/article/pii/S0899900714001920
2. http://onlinelibrary.wiley.com/doi/10.1038/oby.2010.255/abstract
3. http://www.nature.com/ijo/journal/vaop/ncurrent/pdf/ijo201473a.pdf
4.http://ajcn.nutrition.org/content/88/6/1716S.full
5. http://www.fasebj.org/cgi/content/meeting_abstract/24/1_MeetingAbstracts/562.1
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I have long followed Marion Nestle's Food Politics - see here - and have always enjoyed her commentary on the food industry, though I often find myself seeking out the reasoning of the alternative position without blindly following her opinions. One of her recent posts on "Guess Who Funded the Study" was particularly problematic to me.
You can find the post here. Dr. Nestle notes that two conflicting studies came out about the relative content of fructose in drinks -if you're interested in the fructose debate, I encourage you to read David Despain's blog post-interview with John Sievenpiper - see here. The first study was funded by NIH (1), and followed up on a study by Ventura et al (2) that found the mean fructose content of High Fructose Corn Syrup (HFCS)- sweetened beverages to be higher than the 55% that the Corn Refiner's Association reports - see here. The other study, entirely funded by the International Society of Beverage Technologists (ISBT), and authored by Dr. John White, previously known for defending HFCS's similarity to sucrose (4), found that the fructose content of HFCS sweetened beverages randomly obtained from retail store shelves was concordant with the commonly accepted 55% fructose proportions.
Dr. Nestle doesn't go into the methodologies of the study but states that "Really, these kinds of results are so predictable that all I have to do is see the results to guess who must have funded the study. Coincidence? I don’t think so."
Is there something dubious about the ISBT study? There's a couple important issues here related to different methodologies:
- The ISBT funded study used the adapted ISBT method 3.2. The methods that have been established for analysis of HFCS include liquid chromatography and utilizing the refractory index (RI), which determines the dry matter in the syrup. The RI was used to develop the ISBT method 3.0, and was updated to 3.2 which allows for measuring the saccharide content of commercially prepared beverages that contain additives which might interfere with determination of saccharide content. For more on the RI, see here.
- The NIH-funded study used a Metabolomics-Type (MET) Approach (mass spec with combined GC/LC) and Gas Chromatography(GC), and compiled this with previously derived Liquid Chromatography(LC) data from (2).
As noted in the discussion portion NIH study, the original LC data was limited because it didn't include maltose in their measurements - maltose being a disaccharide of glucose could effect the relative Fructose:Glucose. In table 1:formulas , we can see a major limitation: total sugar was measured as sucrose + lactose + maltose + galactose + fructose + galactose. Looking back at the Corn Refiner's site, HFCS is composed of 55 percent fructose, 42% glucose and 3% sugars and other polysaccharides. As noted in the ISBT study introduction, the remaining 3% is composed of maltose, maltotriose, maltotetraose and higher polysaccharides - all polymers of glucose. The NIH study appears to have missed out on measuring these, skewing the relative ratios to appearing to have higher fructose contents.
The ISBT measured fructose, glucose, and these other polysaccharides (refers to them as DP2+) in 80 samples randomly pulled from retail store shelves. The measurement was taken by two independent laboratories that verified the separation and detection methodology and precision, using the accepted ISBT protocol. The authors go on to note that there are limitations to gas chromatography with acid catalysis, which can degrade oligosaccharides but also degrades fragile sugars, which has limited other (unpublished) attempts to report that HFCS contained more carbohydrate than listed (5). White even goes a bit further to suggest that the Ventura et al 's concerns regarding sucrose in their previous findings (2) were a failure to consider acid-catalyzed sucrose inversion to free fructose and glucose that readily occurs in the low-pH environment of carbonated drinks, and that this concern "appears to based on incomplete understanding of sugars chemistry in carbonated beverages" - Oy.
For more on the analyses used for measuring saccharides, the corn refiners association openly lists their protocols: http://www.corn.org/publications/industry-resources/analytical-methods/analytical-methods-toc/
Sometimes, industry association leads to a biased study. Other times, industry means that they are the experts and have hired the best scientists to determine the best methodologies to produce the products they state. Industry being involved with a study should not automatically mean that its results are to be discredited. I'm no analytical chemistry expert as it applies to sugar (I've used HPLC in relation to amino acids in breastmilk), and not many are. Those who are are employed by the CRA and ISBT to figure this stuff out. It's one thing to ask questions about methodology and ask for transparency, it's another to accuse an entire industry of funneling more fructose into the food supply.
1. http://www.sciencedirect.com/science/article/pii/S0899900714001920
2. http://onlinelibrary.wiley.com/doi/10.1038/oby.2010.255/abstract
3. http://www.nature.com/ijo/journal/vaop/ncurrent/pdf/ijo201473a.pdf
4.http://ajcn.nutrition.org/content/88/6/1716S.full
5. http://www.fasebj.org/cgi/content/meeting_abstract/24/1_MeetingAbstracts/562.1
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