High fructose corn syrup has a bad rap. It has been linked and blamed for the obesity epidemic in the United States that has reached alarming levels over the last 30 years.
So, what is HFCS?
- High fructose corn syrup is a product made from cornstarch. Cornstarch is almost 100% glucose.
- HFCS has various forms, all of which are mixtures of fructose and glucose. There are 2 commonly used versions: HFCS-42 and HFCS-55, indicating their ratio % of fructose relative to glucose in composition.
- HFCS is in liquid form and has the ability to withstand pH levels that sucrose cannot. These products are typically used in beverages and food. In other countries it can be referred to as ‘isoglucose’.
- Table sugar is the disaccharide ‘sucrose’, composed of 50% glucose and 50% fructose.
HFCS began replacing sucrose in processed, packaged foods in the 1970s related to:
- functional properties which extend shelf life and preserve ‘freshness’
- aids in fermentation
- maintained structural stability over range of temperature and acidity levels
- maintained texture of baked goods
In the long run- it saves food companies a lot of MONEY!
The HFCS Hypothesis
Until 2004, HFCS was flying under the radar when a study was published in the American Journal of Clinical Nutrition (Bray et al) that deemed it a direct cause of obesity. This hypothesis was based on the rising rates of obesity over the last 30 years and the replacement of sugar with HFCS in the national food supply. (3)
It seems reasonable to suggest a relationship between increased consumption of this product and chronic disease, however evidence from ecological studies linking HFCS consumption with rising BMI rates is unreliable and evidence from epidemiologic studies and randomized controlled trials is inconclusive. (2)
You can find studies to support this hypothesis, but the quality of the studies is continually poor. Check out this review by Dr. John White and his examination of a HFCS vs sucrose study, purporting the HFCS Hypothesis. It really sheds light on how bad information can turn into ‘fact’. Dr. White: Review HFCS-vs-Sucrose Video
–>Just The FactsHFCS and sucrose are fundamentally composed of the same carbohydrate monomers-fructose and glucose. The ratios are slightly different, however the building blocks are the exact same.
Sucrose is a disaccharide and when hydrolyzed in the body by sucrase, it becomes ‘free’ fructose and glucose molecules.
HFCS is composed of ‘free’ fructose and glucose molecules, unbound in solution as monosaccharides. Once sucrose is digested, it is absorbed JUST THE SAME as HFCS.
Composition of Caloric Sweeteners
HFCS 42: 42% Fructose & 58% Glucose
HFCS 55: 55% Fructose & 45% Glucose
Sucrose: 50% Fructose & 50% Glucose
Honey: 49% Fructose & 51% Glucose
Agave: 74% Fructose & 26% Glucose
The Science Behind The Misunderstanding of HFCS:
Fructose and glucose are metabolically different, yielding different absorption rates and endocrine system effects. However, neither sucrose nor HFCS exist in pure form of fructose or glucose, so the differences are irrelevant. Both have nearly identical ratios of fructose and glucose, therefore any variance in the monomers metabolism occurs equally.
- Fructose empties from the stomach more quickly than glucose, is absorbed into the intestine slower and not as thoroughly as glucose.
- In addition, unlike glucose, fructose does not stimulate insulin secretion or leptin levels. Ghrelin levels are also not decreased, as with glucose metabolism.
Although fructose and glucose metabolism are different- HFCS and sucrose are not metabolized differently, therefore distinguishing them as such is incorrect.
HFCS and sucrose both contain the same energy- 4 calories per gram.
So, why is the ‘HFCS Hypothesis’ invalid?
Listed below are 3 research studies which examine various effects on the manipulation of HFCS in the diet, as it relates to obesity markers and health.
- All 3 studies posed the examination and analysis of HFCS as a direct cause to obesity markers and/weight gain.
- All 3 studies concluded that in relation to sucrose(table sugar), HFCS is metabolically equivalent, produces similar clinical biomarkers of obesity and does not contribute more significantly to negative health.
1) Melanson KJ, Zukley L, Lowndes J., Nguyen V, Angelopoulos TJ, Rippe JM. Effects of high fructose corn syrup and sucrose consumption on circulating glucose, insulin, leptin and ghrelin and on appetite in normal-weight women. Nutrition 2007; 23:103-12.
2) Soenen S, Westerterp-Plantenga MS. No differences in satiety or energy intake after high-fructose corn syrup, sucrose or milk preloads. Am J Clin Nutr 2007; 86: 1586-94.
3) Lowndes et al: The effects of four hypocaloric diets containing different levels of sucrose or high fructose corn syrup on weight loss and related parameters. Nutrition Journal 2012 11:55.
1) Melanson KJ, Zukley L, Lowndes J., Nguyen V, Angelopoulos TJ, Rippe JM. Effects of high fructose corn syrup and sucrose consumption on circulating glucose, insulin, leptin and ghrelin and on appetite in normal-weight women. Nutrition2007; 23:103-12
2) Foreshee RA, Storey ML, Allison DB, Glinsmann WH, Hein GL et al. A critical examination of the evidence relating high fructose corn syrup and weight gain. Crit Rev Food Sci Nutr 2007; 47(6): 561-82
3) Bray GA, Nielsen SJ, Popkin BM. Consumption of high fructose corn syrup in beverages may play a role in the epidemic of obesity. Am J Clin Nutr 2004; 79:537-43
4) Soenen S, Westerterp-Plantenga MS. No differences in satiety or energy intake after high-fructose corn syrup, sucrose or milk preloads. Am J Clin Nutr2007; 86: 1586-94
5) Lowndes et al: The effects of four hypocaloric diets containing different levels of sucrose or high fructose corn syrup on weight loss and related parameters. Nutrition Journal 2012 11:55.