When Alan Gaby’s Nutritional Medicine textbook arrived in the mail, my first thought was, "This book weighs a lot." I walked over and placed it on the office scale. It weighs in at just over 8 pounds, 6 ounces. “Dr. Gaby birthed a textbook,” I thought to myself. As I read the textbook, I realized that the analogy of birth was not far from the truth. The information contained in its pages is a culmination of evidence, anecdotal cases, and Gaby's own clinical experience. This seemed to be a rare deviation for a textbook, most of which use only staid information cited from medical literature.
The reason for this departure from the norm is best explained by Gaby himself in the Introduction to Therapeutic Agents: “Because of the low risk of adverse effects and the relatively low cost of most of the therapeutic agents discussed in this book, I believe the reader should be aware of all the potentially useful clinical applications, not just those that are supported by the highest levels of evidence.” (p51) In addition to his experience, the textbook has Dr. Gaby’s immutable writing style throughout: no words are superfluous, there are no irrelevant tangents to distract, and it is at all times obvious that the intended audience is practicing clinicians.
The textbook is divided into 3 parts. The first is a short section (49 pages) titled "Fundamentals of Nutritional Medicine," covering topics such as food additives and food storage and cooking. Part 2, titled “Therapeutic Agents” is 185 pages divided into 4 sections: Vitamins, Minerals, Amino Acids, and Other Therapeutic Agents. Then comes the vast majority of the book: "Medical Conditions." Beginning with chapter 72 on page 239, each chapter explores a different condition. 263 conditions later, this section ends at chapter 335, page 1272. The next section, called “Modalities,” reviews many novel pieces of clinically useful information to address symptoms that may arise from conventional interventions such as anesthesia and radiation. Finally, the last chapter is a concise overview of drug-nutrient interactions, with an emphasis on drug-nutrient depletions. Without the index or the appendix on Food Elimination, the text of this book spans a total of 1322 pages. I cannot recall ever having read a textbook of such breadth that was authored by one person. Certainly, there have been texts with a single author’s name attributed, but in truth that person is generally the editor with many authors contributing. Having written a fair amount myself, I am left in awe of the gargantuan task Gaby has completed.
What is the clinical utility of Nutritional Medicine? I asked two other practicing naturopathic physicians to use the textbook and give me feedback regarding its strengths and weaknesses. Teresa Silliman, ND, has been practicing for more than 10 years and has an emphasis in women’s health. Catherine Clinton, ND, is a more recent graduate whose interests are autoimmune disease and gastrointestinal complaints. My specialty is naturopathic oncology, and I have seen oncology patients exclusively for many years now. Interestingly, despite our differing knowledge bases, many of our observations about the book were in lock step. Namely, we were impressed by Gaby’s approachable and easy-to-understand writing style, the well organized chapters and index, and the impressive number of references, including some too obscure to find through mere internet searching. Of course, our commonality is that we are all clinicians. It is clear that Gaby has taught many clinicians through the years and understands how to distill information, whether from trials or molecular biology, into useful patient care-oriented take home points.
It is clear that Gaby has taught many clinicians through the years and understands how to distill information, whether from trials or molecular biology, into useful patient care-oriented take home points.
The three of us also agreed that this would be the go-to textbook for that moment when you realize you are about to see a patient with a condition you haven’t thought about in many years. Each condition begins with a short summary, then goes into clinical considerations divided into three sections: Dietary Factors, Nutritional Supplements, and Other Treatments. There are references throughout the text, whether from clinical trials or case reports of therapeutic agents.
Let’s look at chapter 306 on Beta Thalassemia as a sample chapter. First, under Dietary Factors, we find that patients with this condition who drank black tea with their meals reduced their iron absorption by 41-95%, a desirable effect given the propensity for iron overload with blood transfusions that often accompany the disease. Moving on to Nutritional Supplements, considerations include folic acid, L-carnitine, magnesium, vitamin E, B6, riboflavin, vitamin C, and zinc. Each of these supplements has multiple lines of evidence regarding possible therapeutic usage. In the case of B6, Gaby cites evidence suggesting the conversion of pyridoxine to pyridoxal-5-phosphate (P5P) is impaired. Both genetics and a deficiency in riboflavin, the cofactor for the rate-limiting enzyme pyridoxine phosphate oxidase, are implicated in the impaired metabolism. Regardless of the cause, he suggests one consider supplementing B6 specifically in the form of P5P in this population, along with riboflavin. In the same chapter, under the heading Other Treatments, he cites a small trial of wheat grass juice. Consumption of 100 ml of wheat grass juice daily decreased transfusion requirements by 25% in more than 50% of study subjects. This chapter is an example of how the evidence is woven together with a thoughtful consideration of what has possible therapeutic benefit without risk to the patient. It is this perspective, from a long-time practicing clinician, that is infused throughout the book, bringing with it a clinical utility that busy practitioners can appreciate.
The shortfalls of the book were few and none of any substantial note. Absent for each condition was a thorough review of the progression and clinical presentation. Of course, this information can be gotten from reliable references such as Cecil’s Textbook of Medicine or the Merck Manual. As Gaby admits, this textbook was never intended to be exhaustive, but to be a review of therapeutic agents and a compilation of the must-know natural medicine interventions for given conditions. Certainly, at the size and weight of the current volume, any additions to the chapters would warrant at least a two-volume set. From clinicians who are just graduating to those that have been out long enough to forget a few things, this book is an invaluable resource for any practitioner who uses natural medicine in his or her practice, regardless of degree or years in practice.
Dr. Gaby's book is available through his website www.doctorgaby.com.