Blue cheese or bleu cheese is cheese made with cultures of the mold Penicillium, giving it spots or veins of the mold throughout the cheese, which can vary in color through various shades of blue and green. This carries a distinct smell, either from that or various specially cultivated bacteria.

Why blue cheese is bad for you?

Consuming spoiled blue cheese can cause food poisoning, which causes symptoms like nausea, vomiting, diarrhea, and stomach cramps ( 5 , 6 ). Certain types of mold also produce mycotoxins, which are toxic compounds that can suppress immune function, cause digestive distress, and even contribute to cancer ( 1 ).

Why is it called blue cheese?

This special mold creates the unique veins of blue or blue-green mold throughout the cheese. It is these blue veins in the cheese that gave it its name, as well as its signature sharp and salty flavor. These veins of mold, along with certain types of bacteria, also give blue cheese its special smell.