Several Chinese studies indicate the goji berry is a rich source of antioxidants and that components of the berry have the ability to stop the growth of cancer cells, reduce blood glucose and cholesterol levels and enhance the effects of radiation on lab animals. But only one of the published studies tested the effects of goji on human beings, and that's a concern for Dr. Jeffrey Blumberg, director of the Antioxidants Research Laboratory at Tufts University.
"In a test tube you don't have to go through the gut," he said.
A 1994 study in the Chinese Journal of Oncology found that 79 cancer patients responded better to their cancer treatments when goji was added to their regimen.
Dr. Victor Marcial-Vega, an oncologist from Hato Rey, Puerto Rico, said that he agrees with those findings, and has been using goji to ease the side effects chemotherapy and radiation is his own cancer patients.
In his 2005 study, which has not been published, 80 percent of his patients who took goji while undergoing cancer treatment maintained a healthy blood count, and 87 percent experienced changes that indicated their immune systems may have improved, he said.
"The results are so dramatic that the doctors will never go back to saying never use antioxidants with chemotherapy," he said.
But, according to Blumberg, cancer patients do need to be aware that an antioxidant like goji juice can interfere with their treatment.
"It's a subject of enormous controversy," Blumberg said. "It depends on which drug or which set of drugs your taking, and which antioxidant you're talking about."
The success of studies abroad and the controversy at home peaked the interest of Dr. H. Leon Bradlow, of the Strang Cancer Research Laboratory in New York, who recently began his own research on the goji berry.
"Natural products have their worth," Bradlow said. "Half of the medications out there originate from natural products."
Bradlow said his tests, which have not been published, showed that the juice extracted from the berry prevented the growth of breast cancer cells. He hopes to go forward with his study and test goji juice on lab mice with cancer.
But until the juice is tested extensively on humans with cancer, he said he has no proof that Goji is worth consuming.
"I haven't the plainest idea," he said. "I don't know if it's good, bad or indifferent."