Sugar debate: Local researcher weighs in on fructose study

Dr. Jean-Marc Schwarz, a researcher and professor at Touro University in Vallejo, studies the metabolic effect of fructose. (Robinson Kuntz/Daily Republic)

FAIRFIELD — Fructose – it seems as if it’s in everything we eat and drink today.

It’s in our energy drinks, cereals, desserts and sodas.

Fructose itself is a naturally occurring monosaccharide, or, simple sugar, found in many plants. It’s a nutritionally important carbohydrate, yet in recent years researchers have argued that fructose is one of the leading causes of diabetes.

Researchers and dietitians dispute that it isn’t necessarily the fructose found in fruits and other plants that are harmful – with the exception of people with diabetes – it’s the added sweeteners such as high fructose corn syrup that are cheaply produced and provide little nutritional value.

A recent study by Yale School of Medicine researchers now argues that consumption of fructose may cause overeating.

The study finds that when another monosaccharide glucose is consumed, it suppresses brain activity that promotes a desire to eat. Fructose, by contrast, is allegedly found unable to suppress that desire.

Dr. Jean-Marc Schwarz, a researcher and professor at Touro University in Vallejo, has been studying the effects of fructose for the past 20 years. While he’s skeptical to accept the Yale study point-blank, he acknowledges that it has merit.

Schwarz studied the metabolic effect of fructose and how it differs from glucose.

The way they are metabolized is a key difference, Schwarz said. Most glucose remains in the bloodstream as energy, while excess glucose is stored in the liver as glycogen, or stored energy. When there is excess fructose, the liver converts it and stores it as fat.

This is why, Schwarz said, drinking a large sugary soda, for example, creates a “tsunami effect” in the liver.

“The liver is very overwhelmed and has to break down the fructose,” he said.

With the popularity of the ingredient, Schwarz focused much of his research on the effect of high fructose corn syrup. He compared the consumption of high fructose drinks to that of force feeding a duck to fatten it for foie gras.

Whether or not fructose intake actually causes overeating, Schwarz said limiting fructose intake is essential either way.

“Reducing sugar consumption is a good idea,” he said. “It stays in the liver . . . it may not be perceived by the brain . . . We do not have a full understanding yet.”

The threat of fructose and overeating may be plausible, but Sharon Martin, a dietitian with NorthBay Medical Center, is more worried that Americans are regularly substituting high-fructose foods over whole, nutritious foods.

“By consuming a processed beverage or food, we miss out on many vitamins, minerals, fiber and other components important in maintaining our health,” she said.

There are some ways people can reduce fructose consumption without going hungry, Martin said.

Replacing sweetened beverages and drinks with unsweetened or naturally sweet foods and drinks is one simple way to cut sugar intake. Choosing water over soda or fruit over cake can save hundreds of calories.

Martin also suggests reading the ingredients label, in addition to the Nutrition Facts Label, carefully before buying. The ingredients are listed in order of amount, the first being the most plentiful ingredient.

And if you’re eating out, ask for nutrition information on the meals.

“If you don’t see it, ask,” she said.

Reach Heather Ah San at 427-6977 or hahsan@dailyrepublic.net. Follow her on Twitter at www.twitter.com/HeatherMalia.

Heather Ah San

Heather Ah San covers Rio Vista, features and general news for the Daily Republic. She received her bachelors of art degree from the University of Oregon.

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