A Closer Look at Stinging Nettle's Effectiveness
Stinging Nettle and Scientific Evidence
One small, preliminary study suggested that stinging nettle worked better than a placebo (a "sugar pill" with no active ingredients) for treating allergy symptoms.
Another study suggested that stinging nettle (in combination with other dietary supplements) may improve the urinary symptoms of an enlarged prostate, although another similar study showed no benefit for the supplement.
There is a little evidence that suggests that taking stinging nettle by mouth or applying fresh stinging nettle leaves (to "sting" the joint) may help with osteoarthritis.
At this time, there is simply not enough scientific evidence to suggest that stinging nettle really works (or does not work) for other uses. Again, more studies are necessary before stinging nettle can be recommended for such uses.
There is little high-quality evidence to show that stinging nettle really works for most uses, although it seems to show promise for some conditions (such as for allergies, an enlarged prostate, or osteoarthritis). As is often the case with dietary supplements, some of the more outlandish claims about the health benefits of stinging nettle should be viewed with skepticism (or at the very least, with caution) until more research is available.