The sprouting of wheat into wheat grass destroys the lectin that is problematic in wheat. Sprouting also beneficially changes the nutrient profile of this grain, resulting in a nutrient-dense, enzyme-rich superfood. Because of these factors, I consider wheat grass to be an excellent addition to the diet for all blood types. As far as an amount, use your own judgement. Because of the concentrated nature of this food, a little goes a long way, so if you have not enjoyed wheat grass juice before, start with a smaller amount.