One caveat: don't expect all the recipes in this book to be low-cal, as they aren't. Tahini and peanut butter are two common ingredients. That may or may not be important to the reader.
Another caveat: depending on where the reader lives, some of the ingredients may be difficult or impossible to buy in smaller areas. E.G. flaxseed and other uncommon oils, algae, and a number of vitamin powders.
For those who want health information as well as smoothie recipes this makes an excellent book for reading, and deciding applicability to one's own health goals.