Irish Moss
Those people on blood thinners and anticoagulants should consult their doctor before taking this herb (which is a sea vegetable) as it does thin the blood a bit. Some people may be allergic. One resource I read said that carragheenans were suspected of being carcinogenic and could possibly cause ulcerative colitis, but Dr. John Christopher (a famous herbalist) uses it in many ways not even discussed here and often for cancer.