spirulina

Does anyone here use spirulina while fasting. I bought a jar of it at whole foods today. I knew it was a blue green algae and planned on adding it to my green juice, because it is a raw superfood. But I didn't know that it is full of protein. It says it is good for detoxing and for fasting. But isn't protein contraindicated during a fast?

I don't know what to do. Should I take add it to my juice or not?