Researchers have discovered a link between the popular anti-depression herb St. John’s wort and the development of cataracts.
Published in Current Eye Research, the study describes the results of questionnaires sent to over 31,000 people over age 40 about cataracts and their use of herbal remedies and treatments over the prior year. Those who reported that they had cataracts were 59% more likely to also report they had used St. John’s Wort. Researchers do make clear that this questionnaire format has limits and further study is necessary to determine whether the correlation is dose dependent and learn more about the timing of taking the supplement and developing the cataract.
In earlier research, Hypericin, an active ingredient in St. John’s wort, was linked with crystallization of the eye’s lenses. But, to date, the association had not been evaluated in humans.
St. John’s wort is a European weed whose extracts have been used for the treatment of mental disorders, particularly depression. It is usually taken as an herbal tea or tablet.