by Vanessa Garlepp
It’s Saturday night. You’ve had a long week, and it’s time to settle down for a quiet dinner at home. Picking up your phone, you call McDonald’s to place an order and soon find yourself enjoying a grilled chicken sandwich with barbecue sauce, plus a side of apple dippers and a fruit and walnut salad. Good work–you’ve managed to craft a healthy meal from a fast food restaurant. Or have you?
What if you discovered that your dinner contains approximately 29 grams of fructose, [1] a fruit sugar found in most American foods [2]? Fructose is widely integrated into the Western diet due to its sweetness–up to 1.28 times sweeter than table sugar–and inexpensive manufacturing process [3]. The human body can comfortably process up to 25 grams of fructose per day [2]; however, beginning in the late 1900’s, the introduction of high-fructose corn syrup (HFCS) to the Western diet has increased average fructose consumption to 85-100 grams per day [4]. This means that in a single meal, you may have consumed more fructose than your body can comfortably handle. Perhaps it’s time to rethink your McDonald’s order.
U.S. fructose consumption is dominated by sweetened beverages (30.1%), grains (21%), and fruit/juices (19.4%) [5]. Almost every soda contains large amounts of HFCS, leading to exorbitant fructose consumption: for example, a medium Dr. Pepper soft drink contains 27.25 grams of fructose, [6] and one 16-ounce Sprite contains 32.4 grams [7,8]. And yes, fruit: despite its numerous health benefits, fruit is the number one source of naturally occurring fructose. One apple contains about 7.5 grams, and one cup of grapes contains 11.7 grams [6].
It may be simple enough to avoid these obvious sugar sources; unfortunately, many “healthy” foods also contain high amounts of fructose. Despite studies proving that sports drinks with carbohydrates (including fructose) cause gastrointestinal symptoms and poorer overall performance, companies such as Gatorade still add excessive amounts of fructose to their products. For example, one 20-ounce bottle of lemon-lime Gatorade includes 15.5 grams of fructose [6,9]. Granola bars are another common source of fructose: HFCS can be used to hold the ingredients together, resulting in up to 11.1 grams of fructose per bar–sweeter than a full-sized Kit Kat [6]! This tendency of “healthy” foods to conceal high levels of fructose can be extremely detrimental to those who turn to them for nutritional benefits.
As a consequence, fructose constitutes over 10% of Americans’ daily calories [5]. The age group with the highest fructose consumption level is adolescents (ages 12-18), who average a daily fructose intake of 72.8 grams [5]. This is likely a result of the vast amount of junk food available to teenagers from vending machines, fast food restaurants, high school/college cafeterias, etc. However, high-fructose diets are also common among young children–kids between the ages of 2 and 5 consume an average of 44.9 grams of fructose daily, which is almost double the amount of fructose an adult can process [5,2]! The main problem? Fruit juice. Despite the widespread belief that juice is a healthy beverage, almost all “100% fruit juices” contain added sweeteners. For example, a single box of apple Juicy Juice–one of the most common juice brands–houses 8.1 grams of fructose alone [7].
In addition to increasing calorie intake, high-fructose diets lead to severe biological consequences that are manifested throughout the U.S. population. Excess fructose consumption triggers enhanced lipogenesis, a process of fatty acid synthesis which causes the buildup of triglycerides (fat) [4]. Furthermore, as opposed to its counterpart (glucose), fructose fails to stimulate insulin secretion and is not carried to the brain upon absorption [3]. Since insulin is a key hormone that regulates food intake and body weight, its absence leads to increased fat storage [3]. Additionally, since fructose does not reach the brain, it cannot signal satiety and may cause the consumer to continue eating without realizing that he or she is full [3]. This combination of biological mishaps can lead to metabolic syndrome, a cluster of conditions (including increased blood pressure and blood sugar, insulin resistance, and obesity) that increases the risk of cardiovascular disease and Type 2 diabetes [4]. High-fructose diets can also cause lasting detrimental health effects in children: the high fructose contents of “100% fruit juice” caused a doubling of childhood asthma in the years 1980-1995 [11]. Therefore, an increased awareness of the prevalence of fructose in the American population is necessary in order to prevent these serious health concerns.
Due to the pervasiveness of HFCS in the U.S., fructose consumption may be inevitable; however, there are some strategies you can implement to avoid flooding your system with fructose. First, always read ingredient labels on store-bought items. Even if it seems unlikely that a certain product will contain HFCS, there are several fructose-containing foods that may surprise you: that barbecue sauce that you decided to include with your dinner contains 8.75 grams [1]. In addition, choosing foods that contain equal amounts of glucose and fructose can mitigate the negative effects of fructose on your body [5]. When eaten on its own, fructose is poorly absorbed by the intestine, enters the colon as a complete saccharide, and is fermented there [10]. This causes gastrointestinal distress and excessive gas, and is commonly known as fructose malabsorption [10]. Luckily, fructose absorption is aided by the presence of glucose, so choosing foods containing a fructose:glucose ratio near 1:1 can mitigate digestion issues [5]. Instead of buying the Juicy Juice cited earlier–which contains a F:G ratio of 2.38:1–consider Tropicana 100% Orange juice, which boasts a more reasonable ratio of 1.17:1 [7].
Given the presence of hidden HFCS in everyday foods, avoiding fructose altogether may prove to be an unreasonable goal. However, by reading ingredient labels and choosing to consume fructose in foods with an equal amount of glucose, it is possible to mitigate the negative health consequences of fructose overconsumption. Many health programs seek to increase awareness about the dangers of fructose and reduce its widespread availability, particularly in school cafeterias. Nonetheless, the next time you order McDonald’s on a Saturday night, try swapping out barbecue sauce for ranch dressing or trading the apple dippers for a fruit and yogurt parfait. This way, you can implement your new knowledge of high-fructose foods to make informed decisions and avoid unnecessary fructose consumption.
[1] Traditional Oven. https://www.traditionaloven.com/foods/menu/fast-food/ (accessed 10 Oct., 2020)
[2] Gibson, P.R. et al. Aliment Pharm. Ther. 2006, 25, 349-363.
[3] Bray, G.A., Nielsen, S.J., Popkin, B.M. Am. J. Clin. Nutr. 2004, 79, 537-543.
[4] Basciano, H., Federico, L., Adeli, K. et al. Nutr. Metab. 2005, 2.
[5] Vos, M.B. et al. Medscape J. Med. 2008, 10.
[6] NutritionData. https://nutritiondata.self.com/ (accessed 10 Oct. 2020)
[7] Walker, R.W.; Dumke, K.A.; Goran, M.I. Nutrition. 2014, 30, 928-935.
[8] The Coca-Cola Company. https://www.coca-cola.ca/brands/sprite (accessed 9 Oct., 2020)
[9] van Nieuwenhoven, M.A., Kovacs, E.M.R., Brouns, F. Int. J. Sports Med. 2005, 26, 281-285.
[10] Latulippe, M.E.; Skoog, S.M. Crit. Rev. Food Sci. Nutr. 2011, 51, 583-592.
[11] DeChristopher, L.R.; Tucker, K.L. Nutr. J.2020, 19, 60.