Where did you read that wheatgass stimulates the thyroid at.And when you say stimulates what do you mean by that?The juiceman jay kordich said in his taped seris that wheat and barly grass helps to bring balance to the thyroid.The thyroid has receptor sites on it for iodine.Iodine can stimulate the thyroid and chlorine is similar to Iodine on a molecular leval.So you might want to avoid tap water and salt.All greens are powerfull foodstuffs surley your not afraid to consume spinach or brussel sprouts or lettuce or cabagge.I think you get my point,I have never heard of anyone being hurt by green juice.Be wise be green be healthy!!!