By Dr. Neil
Few herbal agents have been as widely studied and traditionally used as ginseng. Panax ginseng is the most commonly used form, and has been seen prescribed in Korean herbal medicine as far back as 1610 A.D. The word panax is derived from the greek word “all healing”, and has been traditionally used to treat a variety of different ailments ranging from improving mental focus and clarity, to natural male enhancement (e.g. libido/erection). Currently there is a myriad of literature studying the various benefits of ginseng, but the areas with the most robust, quality literature are cognition, subjective well-being, and male enhancement. Lets look at the studies and what they suggest.
When looking at panax ginseng's impact on cognitive function, the general consensus is that the panax ginseng has an acute improvement in cognitive function. A double blind placebo controlled trial conducted on 30 individuals suggested that when given 200 mg of ginseng, there was a statistically significant increase in cognition, social function, and mood. However, one important note with the study is that the improvements were attenuated after week 8 of consumption. These benefits were repeated in another randomized placebo controlled double blind trial in which subtracting serial 7’s were assessed in those given 200-400 mg of ginseng compared to those without. In the trial, there was a statistically significant improvement in the test subjects receiving ginseng . There was then a third study showed similar results when healthy subjects were given 200 mg of ginseng and had a statistically significant improvement in arithmetic as well as a trend towards a generally improved sense of well being. While the literature may suggest that the cognitive benefits of ginseng may decrease after 8 weeks, the benefit during the 8 weeks of consumption was certainly observed. That being said, the studies were all small and while randomized controlled, not necessarily generalizable to every single person.
A sense of “well being” is very subjective and variable. However the literature on the subject has done a reasonably good job of assessing improvement in mood. In a double blind, randomized control trial conducted on 36 individuals during which each subject received 100 mg of ginseng for a period of 8 weeks, subjects had a statistically significant improvement in mood, body weight, and glycemic profile . There was a similar result seen in a larger, 384 individual randomized controlled trial in which post-menopausal women received ginseng for a period of 16 weeks. The women in the trial did not have a reduction in post-menopausal symptoms, but did have a statistically significant reduction in depressive symptoms and an improvement in a general sense of well being . While the studies show promise, there are always numerous confounders when looking at mood and well being – e.g. other study conditions, diet, uncontrollable confounders. Fortunately, there were no studies suggesting a dysphoric effect on mood, which suggests that there may be some significant benefit.
The last area with a robust body of literature is an effect on male enhancement. The first study was a randomized controlled double blind trial conducted on 60 men with mild erectile dysfunction, who received 3 grams of ginseng daily. The test group showed a statistically significant improvement in erectile function when compared to the placebo. The next study had similar results when 90 subjects received 2,700 mgs of ginseng over a period of 8 weeks and reported a statistically significant improvement in the quality of erections . The third study, also randomized placebo controlled, double blind trial looked at 90 individuals who received 2 grams of ginseng daily for a period of 8 weeks. The study also found a statistically significant improvement in erectile function . The studies while well conducted all had a few fundamental flaws, first they were all using mega-doses of ginseng (1-2 grams daily), with studies done on a limited number of subjects (30-60), and done primarily in Asia. That being said, the studies are positive enough to suggest benefit without harm and could potentially have some significant improvement.
Overall, the literature on ginseng is positive. The benefits were best summated in a systematic review looking at over 57 randomized controlled trials. The review suggested that the literature studied showed benefit in cognition, subjective well being, erectile function, and glucose metabolism, while having a good safety profile . That’s certainly enough for me to recommend ginseng as a solid herbal adjunct to any regular diet.
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