Consider the humble Russian tarragon plant.

A hardy herb with tiny flowers and slender leaves that thrives around the world despite drought and neglect, it’s been used for medicinal purposes for centuries.

Records of its use as a healing herb have been found in writings of the ancient Greeks, dating back to 500 B.C.

People still turn to Russian tarragon today, in the form of dietary supplements touted as being able to enhance the metabolism of carbohydrates.

Were the ancients on to something?

“The early work suggested that there may be some benefits for humans,” said Dr. William Cefalu, a physician who heads the Botanical Research Center at Pennington Biomedical Research Center, which has researched Russian tarragon and other herbs popular as supplements.

“I am nowhere near suggesting we are at a point where we can recommend any of these things. At this point, we’re just trying to dispel myths,” Cefalu said.

Another botanical supplement that the center has studied is SLH, a Chinese herb advertised as advancing weight loss and glucose control. It does absolutely nothing, he said.

“We’ve proved over and over again it doesn’t work,” said Cefalu, an endocrinologist whose special area of interest is diabetes.

The Botanical Research Center at Pennington is one of five such centers in the country funded by the National Institutes of Health to study dietary supplements derived from plants.

The other centers are the University of Illinois at Chicago, the University of Illinois at Urbana-Champaign, the University of Missouri and Wake Forest University.

Each of the centers has its own health-related focus on botanical supplements.

The focus of the center at Pennington is on pre-diabetes.

“We’re trying to find plant chemicals that alter the path of diabetes,” said Cefalu, referring to Type 2 diabetes, formerly called adult-onset diabetes.

Type 2 diabetes is a chronic condition of high glucose levels in the blood, caused by the body’s inability to use insulin, a hormone that helps the body use glucose for energy. It’s the seventh leading cause of death in the country, according to the Centers for Disease Control and Prevention.

Currently 8.5 percent of all Americans suffer from Type 2 diabetes; in East Baton Rouge Parish, that figure is 10.8 percent, according to the CDC.

“If you ... exercise and lose 5 percent of your weight, you have a close to 60 percent chance of delaying the onset of diabetes,” he said.

Effective exercise and weight loss, however, are hard for many people to achieve and sustain, and researchers are trying to learn if there are plant-based chemicals that can help, he said.

The work the Botanical Research Center at Pennington Biomedical Center is doing on supplements is analogous to the rigorous research that pharmaceutical companies undertake to win approval from the U.S. Food and Drug Administration for medications.

Currently, there’s nothing like that FDA oversight for the supplement industry.

“Unlike medicine, the supplements industry is not regulated,” Cefalu said.

That’s the reason the NIH (specifically its Office of Dietary Supplements) founded the Botanical Research Centers Program in 1999, in response to a congressional mandate.

Pennington’s Botanical Research Center was established in 2005, and last year, it received its second five-year grant from the NIH.

The 2007 National Health Interview Study found that about 18 percent of adults in the U.S., take a non-vitamin, non-mineral natural product, and those consumers collectively spend about $15 billion annually on such supplements.

And there are a lot of supplements out there on the market, more than 30,000, Cefalu said.

Complicating the issue for consumers is that the chemical makeup of the plants used to create botanical supplements varies widely according to the plants’ growing conditions, whether the plant was flowering or non-flowering when it was harvested or how it was processed and stored, he said.

“There’s a complexity the public needs to know about,” Cefalu said.

Two supplement products of supposedly the same herb might in fact have completely different chemical compounds, he said.

“We’re studying products that may be useful for human health,” Cefalu said.

Many of the botanicals being studied by the five different botanical research centers in the country appear on a National Business Journal list of the top 100 dietary supplements, according to a recent Pennington newsletter.

To undertake its study of plant-based supplements, Pennington has partnered with Rutgers University in New Jersey.

“We are to human diseases what Rutgers University is to plants,” Pennington’s Cefalu said.

Under carefully controlled circumstances in large greenhouses, Rutgers researchers grow the plants hydroponically from seed, in water solutions, said David Ribnicky, a research associate at Rutgers and an adjunct professor at LSU.

Rutgers later processes the plants and ships them to Pennington in the form of vials of powder to be mixed in food for animal studies or in capsule form for studies for humans.

The Russian tarragon herb (artemisia dracunculus), mentioned previously, is one of hundreds of species of the plant genus Artemisia.

In pre-clinical, animal studies of laboratory rats, the researchers at Pennington’s Botanical Research Center found a “significant amount” of evidence that Russian tarragon did, indeed, positively affect the metabolism of carbohydrates, Cefalu said.

The metabolism of carbohydrates, which includes sugars, breaks them down into energy for the body; diabetes is a related disorder of carbohydrates metabolism.

The local Botanical Research Center has also had two small, human studies of Russian tarragon, Cefalu said. The first study had negative results; in the second, which used larger doses of the tarragon, “positive trends were there,” he said.

Next year, the center plans to hold a larger study with humans, Cefalu said.

Cefalu said that anyone taking both dietary supplements and prescribed medications should let their doctor know, in case there could be interactions with the medicine.

“Claims on supplements need to be evaluated carefully,” Cefalu said. “Controls on supplements are not regulated. Just because it says it’s natural doesn’t meant it’s good for you.”