Enteroimmunology: A Guide to Prevention and Treatment of Chronic Disease,
by Charles A. Lewis, MD
Psy Press; 602 Riverview Dr., Carrabelle, Florida 32322
© 2013; $71.50; 450 pp.
This is the textbook that I wish we had used a quarter-century ago when I was in naturopathic school; I might have helped a great many more patients if it had been. Only problem: back then much of the information in this book wasn't known yet. Even the book's title, Enteroimmunology, was probably not a word back then.
Enteroimmunology is defined as the prevention and treatment of diseases that are initiated in the intestine. As naturopathic doctors, we view pretty much every disease as beginning in the intestine, so in a way this book may prove to be a fundamental text for our profession.
We all know the basics: half of our immune cells guard the intestinal borders, the gut microflora far outnumber the cells in our body, dysbiosis gives rise to no end of problems. We have all known that much. What we haven't learned are the nitty-gritty details that are needed if we are to really succeed in treating complex health problems that originate in the gut.
Thinking in terms of the gut as an immune control system provides a framework for understanding and treating a range of disorders and conditions that are not commonly associated with gastrointestinal function. Pain syndromes such as fibromyalgia; autoimmune conditions such as multiple sclerosis, lupus, rheumatoid arthritis, Hashimoto's, and psoriasis; inflammatory diseases, including IBD; acne; mood disorders such as depression, fear, anxiety and rage disorders; and so on can all be seen as responses to diseases of gut immunity.
Regular readers of this journal won't be surprised that these and other disorders are now considered manifestations of immune dysfunction in the digestive tract. We've been reading and talking about this for years. So in a way, I wasn't expecting much when I picked up this book, figuring it would be old hat to me. I was wrong.
Lewis's contribution is in part to tie together all the assorted details we've been talking about and present it in a logical and comprehensive format that is easily accessible. And, I should add, to talk about it in greater detail and richer depth than we are normally exposed to. Rather than the "CliffsNotes," we get the full story. Lewis's writing is straightforward and easy to follow. While I thought myself adequately informed on this material, I admit to putting circles and stars on every page of the book, marking the new fascinating tidbits and clinical pearls.
The book is divided into 42 chapters. The first 8 chapters review digestive function, detailing digestion of carbohydrates, fats, proteins, the bowel's inhabitants, and the various functional mishaps that give rise to maldigestion, in particular flatulence and diarrhea.
Numerous charts summarize information and provide quick reference. One example is a chart of the fructose-glucose ratios in specific foods. Fructose intolerance symptoms are caused by several possible mechanisms. Most of us appreciate that 15% to 20% of people of European descent have symptoms from eating fructose because they have low levels of the fructose carrier GLUT-5, but there are other individuals who have problems from eating fructose even with adequate GLUT-5. In these people, fructose may trigger symptoms simply because the glucose to fructose ratio is imbalanced. The glucose transporter GLUT-2 pulls fructose and glucose molecules out of the gut and into intestinal cells only in a 1 to 1 ratio. So if fructose molecules greatly outnumber glucose molecules, fructose will be left behind; malabsorption will still occur. Few know which foods have a fructose to glucose ratio greater than 1 off the top of our heads. Thus Lewis's chart of fructose to glucose ratios can prove useful. It makes sense of the patient who tells you that apple juice with a fructose to glucose ratio of 2:2 gives them gas, while orange juice with a ratio of 1:1 doesn't. The book is filled with useful charts like this.
Lewis provides bits of information and clinical pearls that prevented me from skimming through the pages. Instead I found myself reading his book page by page, chapter by chapter, seeking out these gems of information. My family has at times lost patience with me as I have been eager to share trivia over the dinner table. Knowing that 12% of an elephant's total body weight comes from its intestinal contents was interesting to this reader, but was more information than my daughter cared to know. Another gem that I marveled at is that raw kidney beans are remarkably poisonous; eating five of them can kill you. This strikes me as useful information when working with patients who believe that all foods should be eaten raw. Another tidbit: eating salt with starchy foods increases their glycemic index. Apparently the salt enhances the action of amylase, speeding carbohydrate breakdown. Not everyone will find these details interesting; but for those of us who spend our workdays hearing about the digestive complaints of strangers, there is a certain appreciation, if not fascination.
Chapters 8 and 9 cover metabolic syndrome, which Lewis blames on a pair of meteors that hit Europe 14 million years ago. Our nation's current obesity epidemic is blamed on high fructose consumption. Did you know that 70% of our calories come directly or indirectly from corn? Speaking of gems.
Chapters 10 through 16 cover immune cells, hypersensitivity, IgE food reactions, mast cell disorders, bioactive amines and mast cells that cause pseudoallergies, leukotriene associated hypersensitivity, and reactions to enzymes in food and the effects of cooking on these reactions.
Chapters 17 through 23 go into greater depth on immune hypersensitivity reactions, chocolate, wine, vitamin D, gluten diseases, biofilms and dysbiosis, and mitochondrial oxidation.
It isn't until he has laid this foundation for understanding the various mechanisms underlying gut dysfunction that Lewis starts in on the problems which we see in our patients and addresses how to treat them. In chapters 24 to 36, he tackles small intestinal bacterial overgrowth, leaky gut, irritable bowel, interstitial cystitis, headaches, hypothalamic pituitary problems, mood disorders, fibromyalgia, autoimmune disease, sexual function, autism, acne, rage, sleep, cancer, and osteoporosis.
These chapters are concise, well-referenced summaries of the current state of knowledge, providing solid and clinically useful information that is never pedantic. Lewis doesn't tell us that inflammatory bowel disease (IBD) patients should avoid potatoes. Instead he first explains in detail why IBD patients seem to be so affected by potatoes, explaining how potato lectins impair protein digestion and how the resultant maldigestion increases bioamine levels in the intestine. He also details the toxic effects of potato glycoalkaloids and explains how to avoid or at least reduce exposure. By the time one has read through this, it's hard not to dump every potato in the house into the compost bin. It is certainly easy to tell a patient with IBD to avoid them. Each chapter ends with a concise summary of what steps you should take with a patient to treat their condition.
I like the way the author of this book thinks, his mix of detail and big-picture thinking. His views on how we should treat disease are totally congruent with my naturopathic way of seeing the world.
My office shelves are filled with textbooks that I rarely open. This book is different; the author covers the conditions that affect a large portion of our patients, and he does it well and in greater depth than most of us have been exposed to before. It's a book that I expect to read over and over.
Glowing endorsements on my part do not mean that the book is perfect. That it is self-published is all too evident. No copy editor has combed through the text to find mistakes. There are small typos, misplaced prepositions, and other grammatical errors that drive me nuts as I read. I read with pen in hand like a schoolteacher, making corrections as I go. Hopefully, these will disappear by the second edition.
The single-page index is worse than lousy; it lists only a fraction of the words or topics that one might wish to search the book for. For example, the index has no listing for fructose, flatulence, thyroid, or even diarrhea. Let us hope that this too is remedied in the second edition.
Dr. Lewis lets personal asides slip into the text occasionally, and these make me like him as a person. I warn you, though, that there is something a little odd about him: While the book provides no biographical information, what is strange is that there is almost no information about him online. That a person can still exist in our modern world with so little online presence is peculiar. Even if he were hiding in some sort of witness protection program, I'd expect Google to find out more information about him than it does. Whoever he turns out to be, is, he has still written a marvelously useful text for us.
Jacob Schor, ND, FABNO