
Fructose is having a public relations crisis. Its reputation
started to take a nosedive several years ago when some nutrition experts
suggested that Americans eat far too much of it and that it is a major cause of
the so-called obesity epidemic. Things got worse when studies provided a
measure of support for this opinion.
While fructose is a
natural sugar found in many fruits, most of the fructose in the American diet
takes the form of high-fructose corn syrup, a processed sugar added to soft
drinks, candy, and other foods. The body metabolizes fructose in a somewhat
different way than it does other sugars—a way that possibly promotes metabolic
syndrome. For example, a study published recently in Nutrition &
Metabolism reported that 10 weeks of drinking fructose-sweetened
beverages significantly increased uric acid levels and other markers of
metabolic syndrome in overweight subjects, whereas glucose-sweetened beverages
did not.
However, other studies supply evidence that pinning the
country’s weight problem on fructose may be unfair. Researchers at the
University of Rhode Island and the Rippe Lifestyle Institute recently
investigated the effects of a 12-week hypocaloric diet (where subjects ate 309
fewer calories per day than their bodies used) on weight loss. Participants
were separated into four groups, each of which was given a different amount of
sucrose or high-fructose corn syrup.
The researchers were interested in seeing whether including
large amounts of HFCS in the diet made it harder for people to lose weight on a
hypocaloric diet. Turns out it didn’t. Subjects in the high HFCS group lost
just as much body fat as members of the other three groups. The authors of the
study concluded, “Similar decreases in weight and indices of adiposity are
observed when overweight or obese individuals are fed hypocaloric diets
containing levels of sucrose or high fructose corn syrup typically consumed by
adults in the United States.”
This doesn’t mean your
diet should include as much HFCS as the average American’s. Added sugars
account for 14 percent of total calories in the typical American diet. That’s
too much. On the other hand, don’t make the mistake of lumping all sources of
sugar together. Some health-conscious eaters have taken their fear of fructose
so far that they avoid fruit. That’s insane. We’re talking about fruit,
people! The fructose in fruit will not harm you. In fact, a study from the
Harvard School of Public Health found that eating a lot of fruit prevents
long-term weight gain even more effectively than eating a lot of vegetables.
Some athletes avoid sports drinks and energy gels that contain
fructose. This is not necessary, either. While research has shown that sports
drinks and energy gels that contain more than one sugar are more effective than
those that contain a single type of sugar (whether it’s fructose or something
else), there is nothing bad about the presence of fructose in such products
provided they are used as intended: before, during, and after exercise.