Q. I recently heard about the Chinese herb luo han kuo being used as an immune booster. What other benefits might this herb offer?

A. Luo han kuo (LHK, or Momordica grosvenori) has been used in Traditional Chinese Medicine (TCM) for at least 1,000 years to strengthen the immune system and treat respiratory problems—and for good reason. Researchers from the Yamagata University School of Medicine in Japan found in 2002 that LHK is rich in immune-boosting antioxidants. These antioxidants also fight free radical damage, and studies show that LHK may help lower cholesterol by preventing LDL (bad) cholesterol oxidation.

More than medicine, LHK is naturally sweet—up to 200 times sweeter than sugar—yet it doesn’t have sugar’s negative metabolic effects. Because it is low on the glycemic index and low in calories, LHK is gaining the attention of American food companies as a possible sugar substitute for both diabetics and dieters. That doesn’t surprise William Young, LAc, PhD, founder of Young Life Holistic Healing in Flushing, New York, and an expert in TCM, who says that Chinese bakers often use LHK instead of sugar in cookies and cakes.

More recently, scientists have focused on LHK’s anticancer properties. Several preliminary studies show that the glycosides responsible for the herb’s sweetness also appear to inhibit tumor formation. Available as a tea or processed into bouillon-type cubes and granules, LHK can be found in most natural products stores.

This Ask the Expert was written by Kim Erickson, an herbalist, health writer, and the author of Drop-Dead Gorgeous (Contemporary, 2002).