Once I had figured out basics of Mushroom biology, I wanted to know what are they made of? Are they meat or vegetables? How much protein and fiber do they contain?

The main stuff that makes up mushrooms is a protein called chitin. It’s a protein that is also found in insect exoskeletons. Hmm… There’s also other nutrients that occur in small amounts and vary according to th e

I looked up mushroom nutrition in the USDA nutrition database. It seems there’s not much of anything in mushrooms. Based on plan-old white button mushrooms, an 8 oz serving (about a packed cup of chopped mushrooms… or three portobello caps. A lot of mushroom) is only 50 calories. Most of the nutrition is from fiber (2.3 g) and protein (7.0g). Compare this to 8oz of flank steak (lean beef) has 440 calories, mostly fat (18.9g) and protein (63.5 g). Really, mushrooms are a fibrous network to hold water.