Fast-food restaurants of the future may have a new menu item: an additive that lets people eat fare high in saturated fat without raising their risk of type 2 diabetes (search).

“It could be formulated into something like a cheese slice,” says Wallace Yokoyama, PhD, a research chemist with the U.S. Department of Agriculture (USDA).

Or, the additive — called HPMC (hydroxypropylmethylcellulose) — could become an ingredient in home cooking. “I don’t see why not,” Yokoyama tells WebMD.

So far, HPMC has helped hamsters avoid blood sugar problems on a diet high in saturated fat (search). That’s the type of fat found in animal products — and on the plates (and arteries) of many Americans. The major culprits of saturated fats for U.S. adults are cheese, beef, milk, and bakery items.

Human trials haven’t been done yet. Yokoyama tells WebMD he hopes those will happen in the next couple of years. Meanwhile, he suggests eating a healthy diet — and takes his own advice. Yokoyama’s lunch yesterday was tuna niçoise salad, not a super-sized burger with fries.

Calories Still Count

Even if HPMC’s human tests succeed, it won’t be a green light to chow down on fatty foods, Yokoyama cautions. HPMC doesn’t shave any calories off foods.

“It’s not going to prevent weight gain, but it does seem to prevent insulin resistance (search),” Yokoyama tells WebMD. “We still recommend moderate intake of calories and moderate exercise.”

Insulin resistance shows that the body’s ability to handle blood sugar is slipping. The problem can lead to type 2 diabetes, which has been rising in the U.S.

What Is HPMC?

HPMC is an indigestible form of fiber made from cellulose (search). You may have already unwittingly sampled it in tiny amounts.

HPMC has been used in many food products for 50 years. It’s added to fillings, sauces, and glazes. With no taste or odor, HPMC lends texture without drawing attention to itself, says a news release from the American Chemical Society, a scientists’ organization.

No negative side effects have been seen from HPMC, says Yokoyama. “We know from another study a couple of years ago that it passes through the digestive system and is excreted intact,” he tells WebMD.

Currently, HPMC accounts for less than 1 percent of the total ingredients in foods containing the additive. It would probably take more than that to avoid insulin resistance, according to the news release.

Targeting Saturated Fat

Yokoyama sees a link between saturated fat and type 2 diabetes. “We’re interested in preventing type 2 diabetes,” he tells WebMD.

When people eat a lot of saturated fats at once, the body can get overwhelmed, he explains.

“In more detail, we think saturated fats will block the transport of glucose (blood sugar) from the bloodstream into tissues,” says Yokoyama. That raises blood sugar levels, driving up demand for insulin to handle the blood sugar spike.

Polyunsaturated fats — found in plant-based foods — don’t have the same effect, he adds. The researchers fed hamsters a diet high in saturated or polyunsaturated fats. The saturated-fat hamsters developed insulin resistance, but the polyunsaturated group didn’t.

A saturated fat binge can also swamp parts of the body not designed for the overload. That includes the liver, heart, and pancreas; pancreatic damage can lead to diabetes, the news release states.

Testing HPMC

For years, Yokoyama and colleagues looked for a solution using natural fiber from oats and barley. When that didn’t work as they hoped, they shifted gears.

“Those natural [fibers] are kind of fragile,” he explains. “We were looking for something a little more stable and more easily controlled, and so we thought we would try HPMC.”

They fed a group of hamsters a high-fat diet similar to what many Americans eat. The hamsters got about 38 percent of their calories from fat and developed insulin resistance. Meanwhile, hamsters on a low-fat diet didn’t become insulin resistant.

A third group of hamsters got a saturated fat diet with HPMC. This time, the hamsters didn’t get insulin resistance.

However, they did gain a bit more weight than hamsters on a healthier diet. Exactly how HPMC works isn’t known, but scientists guess it may slow down fat absorption.

HPMC is made by the Dow Chemical Company, but the study was entirely funded by the USDA. Yokoyama presented the findings in San Diego, at a national meeting of the American Chemical Society. He credits his colleagues, including the University of Minnesota’s chemical engineering and materials science professor Wei-Shou Hu, PhD, for their work.

By Miranda Hitti, reviewed by Brunilda Nazario, MD

SOURCES: Wallace Yokoyama, PhD, research chemist, U.S. Department of Agriculture. American Chemical Society’s 229th National Meeting & Exposition, San Diego, March 13-17, 2005. News release, American Chemical Society.