<<Disclaimer: Verify this information before applying it to your situation.>> I received nine responses about miso. A lot of people use miso with no problems. I recieved some conflicting information about it though due to koji which is used in fermentation. I decided to return the Miso Master Traditional Red Miso because the company couldn't tell me anything about the fermentation process. I bought some instant golden miso which says "gluten free" on the package. See below. Susanne According to the attached web site, the miso contains a fermenting product called koji: <A HREF="http://www.mountainark.com/public_html/catalog/miso.html">Miso/Mt Ark Trading Co.</A> And according to the safe/forbidden/iffy list this is bad news. <A HREF="http://www.celiac.com/forbiden.html">Safe & Forbidden Lists For Celiac Disease And A Gluten-Free Diet</A> If you click on edit and do a find of koji you'll find it down the list. There may be other companies to check out, but this was the organic one. If this one isn't safe I'd be wary of the others. However, you're not going to use that much are you? ANOTHER RESPONSE FROM SOMEONE ELSE I live on miso. Miso Master is a good brand, reliable, too. If they are using a rice koji (culture) to make their red miso, then you will be okay. ( I tend to eat more rice miso than red. I like the mellower flavour of the rice, less salty, too.)