Much research requires still to be carried on, both in laboratories and in homes, on matters pertaining to Diet. Even more, the knowledge, we already have needs to be put into practice and to be broadcast. Food is a matter on which we are very conservative. If this booklet stimulates research, makes at least some people take interest in what they eat and leads them to reform their food habits, it will fulfil its purpose. Considering the importance of the subject, the overwhelming ignorance and apathy which prevail in regard to it are most deplorable, and need to be combated. It is to serve towards this end that this book is published.