American ginseng (Panax quinquefolius), a member of the ivy family, is an herb used in traditional Chinese medicine (TCM) and by Native American healers. The root of the ginseng plant is said to boost energy, prevent infections, and even treat diabetes and cancer.
Indeed, research suggests that compounds found in American ginseng called ginsenosides may stimulate the immune system, inhibit the growth of cancer cells, lower blood sugar, and treat dementia. These studies, however, have been performed on animals and cell cultures; trials in humans are needed to confirm American ginseng's effectiveness.
The overall evidence for American ginseng's health benefits is limited, but the available pool of research is growing. Here's a look at what is known about the herb so far.
Like other forms of ginseng—such as Panax ginseng, a.k.a. Korean ginseng or Asian ginseng—American ginseng has also been found,
in preliminary research, to fight fatigue.
A review of studies published in 2018 stated that American and Asian ginseng may both be viable fatigue treatments in people who have chronic illnesses. However, researchers added that there's a "critical need" for more and stronger trials.
In a 2010 study published in Supportive Care in Cancer, cancer patients who took American ginseng supplements daily for eight weeks showed greater improvements in vitality compared to those assigned to a placebo.
A supplement containing American ginseng plus whole coffee fruit extract and an herb called Bacopa monniera appeared to increase working (short-term) memory when it came to accuracy and response time, according to a study published in a 2019 edition of Nutritional Neuroscience.
That's a promising result, but as this is the first study on the topic, it's far from conclusive.
Maintaining normal blood sugar levels is important for both diabetes prevention and diabetes management. American ginseng may help by regulating blood sugar, according to a 2018 study published in the European Journal of Nutrition.
The study of 39 people with diabetes found American ginseng plus fiber helped lower blood sugar over the 12-week trial.
Though promising, more and larger studies testing American ginseng's effects on blood sugar are needed.
American ginseng may offer protection against viral respiratory tract infections, including influenza, flu-like illnesses, and the common cold, according to a 2017 review.
A 2011 literature review published in the journal Evidence-Based Complementary and Alternative Medicine came to a similar conclusion. The review included five trials of a total of 747 subjects and found taking American ginseng reduced the incidence of colds by 25% compared to placebo.