By Bob Shepard

Kudzu root extract could provide a novel treatment for metabolic syndrome, according to a new report from UAB researchers.

It sure seemed like a good idea at the time. In the 1930s, farmers and government agents across the American South sowed fields with a popular new Asian import called kudzu that promised to help fight devastating erosion problems. The fast-growing plant, native to Japan and China, bloomed in the hospitable Southern climate and quickly ran wild. In 1972, it was officially declared a weed by the U.S. Department of Agriculture. Today, the “vine that ate the South” has gobbled more than 10 million acres. In the right conditions, it can grow up to a foot a day and as much as 60 feet per year—so fast, in the words of poet James Dickey, “that you must close your windows at night to keep it out of the house.”

But this much-maligned invader may contain a beneficial surprise. In findings published in August in the Journal of Agriculture and Food Chemistry, UAB researchers reported that an edible extract from kudzu’s roots may help regulate high blood pressure, cholesterol, and blood glucose—all contributors to metabolic syndrome, a condition that affects 50 million Americans and is particularly pervasive in the South.

Kudzu’s Secret Ingredient

The UAB study focused on substances called isoflavones found in kudzu root, in particular one called puerarin. “We were interested in kudzu because of its long history of use in China and Japan,” says UAB cell biologist J. Michael Wyss, Ph.D., the lead author on the study. “We thought that, like a lot of other plant products, kudzu root extract might have some benefit for cardiovascular function. We found some small benefits, but we got much more excited when we saw the effects on cholesterol and then on glucose metabolism.”

An excessive amount of glucose, or sugar, in the blood is linked to both diabetes and obesity. Wyss says puerarin seems to regulate glucose by steering it to places where it is beneficial, such as muscles, and away from fat cells and blood vessels.

“We don’t know how it works yet,” he says. “It appears that it buffers sugar loads, so when you take in a large amount of sugar, it doesn’t immediately enter your bloodstream but instead enters much more gradually, preventing a sudden surge in blood glucose.”

“At the same time, we think it’s pulling that glucose out of the blood and depositing it into muscles where it can be used for work,” says UAB biochemist Jeevan Prasain, Ph.D., a study co-author.

Kudzu as Complement

However it may work, kudzu is no magic bullet for metabolic disease, cautions Wyss. “I don’t think puerarin would ever be a stand-alone treatment for diabetes, obesity, or any of the other conditions that make up metabolic syndrome,” he notes. “But as metabolic syndrome progresses, a patient needs stronger and stronger doses of medications to control it, and those medications can be toxic at high levels. Our hope is that puerarin will prove to be a complement to existing drug therapy, allowing patients to decrease the amount of drugs they have to take and helping those drugs maintain their effectiveness over a longer period of time.”

Don’t start planting the back 40 with kudzu just yet, though. Prasain says there is no shortage of kudzu root extract from established growers in China, where it has been used for a variety of medicinal purposes for centuries.

“Botanicals are the root, so to speak, of many medicines,” he says. “Aspirin, perhaps the most commonly used drug, comes from willow bark. Plants have developed a myriad of attributes and compounds to fight off their own forms of disease. This gives science a window into how to use these compounds for our own health and wellness.”

This research was funded by the National Center for Complementary and Alternative Medicine and the Office of Dietary Supplement Grants, in collaboration with scientists at the Purdue-UAB Botanicals Center and the Department of Biology of Luther College in Decorah, Iowa