Not all mushroom products are created equal. We use only the whole fruiting body of the mushroom, properly extracted to ensure the beneficial compounds are contained in the final product.
Some companies will short-circuit the growing process using something called “mycelium on grain”. These products will be high in starch from rice or oats.
No matter who you get your mushrooms from, you should ensure that they are made from whole fruiting body and not myceliated grain.