Fructose is naturally found in fruits, honey and some root vegetables. Fructose also makes up half of sucrose; common table sugar. Historically, fructose has typically been eaten in small quantities. This all changed in the late 1970's with the introduction of high-fructose corn syrup.
(HFCS). HFCS is a man-made product produced in the lab from cornstarch (Forrestal). It has no connection to fruit. HFCS contains, by calories, 56.7% fructose and 43.3% glucose and by weight 55% and 42%, respectively (Gaby). In contrast, an apple is about 6% fructose, 4% sucrose, and 1% glucose by weight (Taubes). The annual per capita intake of HFCS from 1970 to 1997 increased from .5 pounds to 62.4 pounds and sucrose consumption decreased from 102 pounds to 67 pounds (Gaby). The amount of fructose increased from less than .5g/day in 1970 to 40g/day in 1997, an 80-fold increase (Gaby). Much of the HFCS is found in soft drinks (it's interesting that these can make you soft i.e., fat), fruit juices, sports drinks and other processed food items. The significantly higher intakes of fructose, from HFCS and pure fructose, has been strongly associated with many adverse health effects.
The negative health effects of fructose have been demonstrated in numerous studies (Gaby, Taubes). The following list highlights what the research (with animals and humans) on fructose has demonstrated (Gaby, Taubes):
- Increased advanced glycation end-products (AGE's, causing increased cross collagen)
- Insulin resistance
- Diabetes mellitus
- Non-alcoholic fatty liver disease
- Hypertriglyceridemia (high triglyceride levels)
- Hyperuricemia (high uric acid levels, may cause gout)
- Irritable bowel syndrome and other digestive problems
- Urticaria (hives)
The ingestion of fructose and HFCS, as well as sucrose and other processed carbohydrate foods, have a strong potential to elicit poor health. However, the ingestion of small amounts of these processed items will probably not cause ill effects and eating real foods (fruits, etc.) with naturally occurring fructose does not need to be avoided. Fruits can be eaten, but should be approached with caution, particularly if dealing with health issues and weight problems. An important point is most of the current fruits available today are much higher in sugar than ones available during almost all of human existence (Billings). Taking an evolutionary perspective helps to clarify the subject. Gary Taubes makes a good point:
With an eye toward primitive diets transformed by civilization, and the change in Western diets over the past few hundred years, it can be said that the single most profound change, even more than the refinement of carbohydrates, is the dramatic increase in fructose consumption that comes with either the addition of fructose to a diet lacking carbohydrates, or the replacement of a large part of the glucose from starches by the fructose in sugar (p.197).
There is no reason (biological) to ingest fructose or HFCS. There are, however, many reasons to avoid these items. Do your body and your health a favor; steer clear of fructose and HFCS. For more info on how fructose can effect your health, see our weight loss e-book.
- Billings, T. (1997). Wild/Natural Fruit vs. Modern/Cultivated Fruit. Retrieved from,
- Forrestal, L. (2003). The Murky World of High-Fructose Corn Syrup, Retrieved from, http://www.westonaprice.org/motherlinda/cornsyrup.html
- Gaby, A. (2005). Adverse effects of dietary fructose. Alternative Medicine Review, Vol. 10. (4)
- Taubes, G. (2007). Good calories, Bad calories. Alfred A. Knoph, New York