High fructose corn syrup (HFCS) is now found in practically every type of refined food. There have been major debates between scientists and nutritionists and those who represent the corn syrup industry regarding the safety of this ingredient. Increasingly, research has found the ingredient is linked with higher risks of obesity and diabetes.
But one might find it surprising high fructose corn syrup is associated with greater incidence of respiratory conditions such as asthma, chronic bronchitis and COPD (chronic obstructive pulmonary disease).
Case in point: A 2015 study has found that the consumption of high fructose corn syrup significantly increases the incidence of chronic bronchitis among adults.
The research comes from the New York Medical College and the University of Massachusetts in Lowell, MA. The researchers studied 2,801 people between the ages of 20 years old and 55 years old. To establish correlations, the scientists utilized health data from the National Health and Nutrition Examination Survey of 2003-2006.
The researchers conducted an analysis of data between those people who had a history of chronic bronchitis, and compared this with their consumption of soft drinks.
The research then separated the types of soft drinks consumed, whether diet soda or non-diet, high fructose corn syrup soda. The researchers eliminated potential risks associated with smoking or second-hand smoking, age, gender, ethnicity, obesity, diabetes, and other factors.
The subjects were divided into groups based upon their consumption of HFCS soda drinks: One or less HFCS sodas per month; two to three times per month; one to two times per week; three to four times per week; five to six times per week; one time per day; or two to three non-diet (HFCS) sodas per day.
The study found that drinking five or more HFCS sodas per week increased the incidence of chronic bronchitis by more than 80 percent. This is approaching a doubling of incidence of chronic bronchitis.
The researchers concluded:
“HFCS sweetened soft drink intake is correlated with chronic bronchitis in US adults aged 20-55 years, after adjusting for covariates, including smoking.”
Not the first study implicating HFCS and asthma
This is not the first study that has revealed this association. A 2013 study from the Centers of Disease Control in Atlanta studied the relationship between asthma and soda consumption in U.S. high school students. The study included 15,960 students between the 9th and 12th grades. Of this population, nearly 11 percent of the students were currently suffering from asthma.
The study found that drinking three or more sodas a day increased the incidence of asthma by 64 percent. And just two sodas a day increased the risk of asthma by 28 percent.
Another study – also from the New York Medical College and the University of Massachusetts – found that consumption of these sorts of drinks were linked with asthma among children.
The study analyzed data from the 2003-2006 National Health and Nutrition Examination Survey, which included 1,961 children between 2 and 9 years old. The study found that those children who consumed five or more drinks of fruit drinks (you know the kind with lots of HFCS), soda and apple juice per week had more than a five times (5.29) greater risk of asthma compared to those who drank these drinks one or less times per month.
Apple juice too?
Of course, sodas and fruit drinks are both loaded with high fructose corn syrup. But what about apple juice?
Yes, the researchers found that children who consumed apple juice one to four or five times or more per week were nearly three times more likely to have asthma than those who drank apple juice less than one time per month. It was less than the combined consumption with HFCS as above, but still significant. Why?
Apple juice is one of the few fruit juices that will contain a relatively high proportion of fructose to glucose. Apple juice typically contains about twice the amount fructose than glucose.
Furthermore, most commercial apple juices are made from concentrate. During the concentration process, much of the fructose is freed from the larger polysaccharide chains – and those bound to pulp and fiber such as pectin.
This means the level of what is called free fructose is significantly increased in apple juice made from concentrate.
Apple juice thus contrasts many other types of fruit juices. Still, because of the concentrating process, any fruit juice made from concentrate will also likely contain higher levels of free fructose.
Illustrating these points, the researchers also tested orange juice. They found that not only was orange juice not associated with more asthma incidence: Greater orange juice consumption was linked with less asthma incidence.
Yes, the researchers found that those children who drank five or more glasses of orange juice per week had half the incidence of asthma compared to those children who drank OJ once or less times per month.
This also fits the profile of the free fructose, as orange juice will typically contain a ratio of about 1:1 fructose to glucose. Meanwhile, HFCS will typically contain fructose:glucose ratios between 1.35:1 and 1.8:1.
Furthermore, commercial orange juice is typically offered at the store as not-from-concentrate. This further reduces the amount of free fructose available from orange juice.
Excess Free fructose and asthma and other lung conditions
We should note from the research above that the fructose:glucose ratio is not the only issue here. The apple juice – which contains 2:1 versus up to 1.8:1 fructose:glucose ratio in HFCS – did not spike asthma rates as high as those who drank the HFCS sodas and fruit drinks.
There is another factor. This is called free fructose. As mentioned above, the concentrating process for apple juice concentrate hikes the available free fructose levels. And the refining process of high fructose corn syrup does too – but worse. The researchers also pointed out that fruit drinks, which will contain both apple juice and HFCS are likely the worst combination. Why? Because together they provide higher levels of excess free fructose:
“The opposite tendency towards no association with orange or grapefruit juice further supports the hypothesis that excess free fructose may be responsible for the relationship with asthma.”
Why does excess free fructose increase the risk of asthma?
Researchers hypothesize that upon consumption, excess free fructose produces what are called advanced glycation end products (often called AGE) within the body. When advanced glycation end products are produced by excess free fructose, it is often referred to with the unwieldy acronym of enFruAGE.
Higher levels of advanced glycation end products increase the risk of oxidation in the blood, and thus increase inflammatory processes. This increase in inflammation tends to inflame the respiratory system and increase the production of mucus within the lungs. This promotes the inflammatory processes of bronchitis and asthma.
This is the official version. The unofficial version – actually more of a hypothesis, but one based on many studies – is that excess free fructose provides excellent food for pathogenic bacteria that live in our intestines and our airways.
The advanced glycation end products are just one of the many endotoxins that these pathogenic bacteria produce after they consume simple sugars like excess free fructose. They produce these endotoxins within the intestines, which are released into the bloodstream. These endotoxins in themselves stimulate the inflammatory process because they stimulate the immune system. Why? Because the immune system needs to get rid of these.
The excess free fructose that converts its way into the blood in the form of blood sugars also provides excellent food for the various bacteria that can harbor within our respiratory systems. When these bacteria are provided a diet of simple sugars to expand their colonies, they also produce endotoxins, which increase inflammation within the airways.
It is for this reason that the presence of volatile organic compounds determined from breath testing is a valid way to diagnose asthma. Volatile organic compounds are produced from fermenting bacteria – bacteria that are feeding from the body’s high levels of simple sugars.
So we find a triple-whammy situation: Excess free fructose feeds intestinal pathogens, which release inflammatory endotoxins that flow through the bloodstream. The excess free fructose also produces higher levels of blood sugars, which are easily oxidized and feed bacteria that dwell within our respiratory systems.
Does this mean fruit is bad?
This is the unfortunate conclusion many have made. As illustrated with the orange juice consumption – along with other studies that we examine in my book – the consumption of whole fruits is linked to reduced risk of asthma and bronchial conditions such COPD.
Apple juice from concentrate, as noted above not only by me but by the researchers, is not healthy. Other research has found that it is primarily refined foods that contain high levels of excess free fructose. In terms of the fructose:glucose ratio, the very few exceptions besides apples are pears, mangos and watermelons.
So it is critical to avoid not only any processed fruit juice, but especially juice from concentrates of apple, pear, mango and/or watermelon.
Yet when these very same fruits are eaten raw, they contain numerous healthy fibers and antioxidants that balance their higher fructose levels. When these nutrients are removed in the form of concentrated juice, that balance is lost.
This means that all fruits are best eaten raw. Alternatively they can be drunk as smoothies – basically, the raw fruits are put into a blender.
It is for this reason that I personally am not a juicer. To extract out part of the food while leaving behind the best parts – its pulp and fiber – is senseless. Then of course, you have the hassle of cleaning out all that pulp and fiber out of the juicer strainer – which would have been better to consume with the juice in the first place.
While you can’t call me a juicer, feel free to call me a blender…
DeChristopher LR, Uribarri J, Tucker KL. Intake of high fructose corn syrup sweetened soft drinks is associated with prevalent chronic bronchitis in U.S. Adults, ages 20-55 y. Nutr J. 2015 Oct 16;14(1):107.
Park S, Blanck HM, Sherry B, Jones SE, Pan L. Regular-soda intake independent of weight status is associated with asthma among US high school students. J Acad Nutr Diet. 2013 Jan;113(1):106-11. doi: 10.1016/j.jand.2012.09.020.
DeChristopher LR, Uribarri J, Tucker KL. Intakes of apple juice, fruit drinks and soda are associated with prevalent asthma in US children aged 2-9 years. Public Health Nutr. 2015 Apr 10:1-8.
Cavaleiro Rufo J, Madureira J, Oliveira Fernandes E, Moreira A. Volatile organic compounds in asthma diagnosis: a systematic review and meta-analysis. Allergy. 2015 Oct 17. doi: 10.1111/all.12793.
Adams C. The Ancestors Diet: Living and Cultured Foods to Extend Life, Prevent Disease and Lose Weight. Logical Books. 2014
Case Adams is a California Naturopath and a Board Certified Alternative Medicine Practitioner with a PhD in Natural Health Sciences, and diplomas in Homeopathy, Aromatherapy, Bach Flower Remedies, Blood Chemistry, Clinical Nutritional Counseling and Colon Hydrotherapy. He has authored 26 books on natural healing strategies.