I bought the test strips from amazon and they show my levels are quite high yet I've been on a low (almost no) sulfur diet for over several months. after about 2 months, I started adding it back in slowly it back in, then started having multiple chemical sensitivities so started no sulfur again for the last 5 wks. My pracitioncer thinks I overdid the no sulfur b/c I was having breathing issues and head pressure. Now I may have histamine issues and I'm not able to determine if the breathing symptom is coming from histamine or lack of sulfur. Regardless, I don't understand why the sulfur levels would still be high, so I'm not sure if they're accurate. Any insight? Thanks.