Two New Negative Fructose Studies via Science Daily

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From

http://www.sciencedaily.com/releases/2009/04/090420182151.htm

and

http://www.sciencedaily.com/releases/2009/03/090325091811.htm

Too Much Sugar Is Bad, But Which Sugar Is Worse: Fructose Or Glucose?

ScienceDaily (Apr. 25, 2009) — In 2005, the average American consumed 64kg

of added sugar, a sizeable proportion of which came through drinking soft

drinks. Now, in a 10-week study, Havel and colleagues, at the

University of California at , , have provided evidence that human

consumption of fructose-sweetened but not glucose-sweetened beverages can

adversely affect both sensitivity to the hormone insulin and how the body

handles fats, creating medical conditions that increase susceptibility to

heart attack and stroke.

In the study, overweight and obese individuals consumed glucose- or

fructose-sweetened beverages that provided 25% of their energy requirements

for 10 weeks. During this period, individuals in both groups put on about

the same amount of weight, but only those consuming fructose-sweetened

beverages exhibited an increase in intraabdominal fat.

Further, only these individuals became less sensitive to the hormone insulin

(which controls glucose levels in the blood) and showed signs of

dyslipidemia (increased levels of fat-soluble molecules known as lipids in

the blood).

As discussed in an accompanying commentary by na Hofmann and Matthias

Tschöp, although these are signs of the metabolic syndrome, which increases

an individual's risk of heart attack, the long-term affects of fructose

over-consumption on susceptibility to heart attack remain unknown.

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Journal reference:

1. Stanhope et al. Consuming fructose-sweetened, not

glucose-sweetened, beverages increases visceral adiposity and lipids and

decreases insulin sensitivity in overweight/obese humans. Journal of

Clinical Investigation, 2009; DOI: 10.1172/JCI37385

<http://dx.doi.org/10.1172/JCI37385>

Fructose Metabolism By The Brain Increases Food Intake And Obesity, Review

Suggests

ScienceDaily (Mar. 26, 2009) — M. Lane and colleagues at s

Hopkins have built on the suggested link between the consumption of fructose

and increased food intake, which may contribute to a high incidence of

obesity, and Type 2 diabetes.

Over the past four decades life-styles have gravitated toward the excessive

consumption of 'high energy' foods and sedentary behavior that has resulted

in a high incidence of obesity and its pathological consequences. This

scenario has led to the increased occurrence of insulin resistance and Type

2 diabetes. At present, approximately thirty percent of adult Americans can

be classified as obese. Moreover, these changes now extend into the younger

age group.

M. Lane and co-workers at The s Hopkins University School of

Medicine in Baltimore have now pulled together work, largely in their

laboratory (many papers beginning in 2000), dealing with the role of

malonyl-CoA in the signaling system in the brain (specifically the

hypothalamus) that has inputs into the higher brain centers that determine

feeding behavior, most notably appetite. Two papers in the journal PNAS in

2007 and 2008 showed that glucose and fructose act quite differently in the

brain (hypothalamus) - glucose decreasing food intake and fructose

increasing food intake. Both of these sugars signal in the brain through the

malonyl-CoA signaling pathway and have inverse effects on food intake.

Lane commented: " We feel that these findings may have particular relevance

to the massive increase in the use of high fructose sweeteners (both high

fructose corn syrup and table sugar) in virtually all sweetened foods, most

notably soft drinks. The per capita consumption of these sweeteners in the

USA is about 145 lbs/year and is probably much higher in teenagers/youth

that have a high level of consumption of soft drinks. There is a large

literature now that correlates, but does not prove that a culprit in the

rise of teenage obesity may be fructose. "

The fact that fructose metabolism by the brain increases food intake and

obesity risk raises health concerns in view of the large and increasing per

capita consumption of high fructose sweeteners, especially by youth.

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Journal reference:

1. Lane et al. Effect of glucose and fructose on food

intake via malonyl-CoA signaling in the brain. Biochemical and Biophysical

Research Communications, 2009; DOI: 10.1016/j.bbrc.2009.02.145

<http://dx.doi.org/10.1016/j.bbrc.2009.02.145>

Driscoll

Exercise Physiologist and Sports Dietitian

Sydney Australia