Herbal Reports: St. John's Wort    High-dose Herbs Damage Sperm St. John's wort and echinacea damaged sperm DNA and compromised sperm viability. Only the high concentration of St. John's wort was associated with a point mutation of the BRCA1 gene. Saw palmetto was the only herb that did not have a negative effect on penetration. St. John's Wort Causes Cataracts Sun trap - People using the herb St John's wort, a popular antidepressant, should take care if going out into the sunshine. Researchers from New York have found that a combination of St John's wort and bright light could lead to cataracts - New Scientist