What to eat or not to eat? That is the question.
Some time ago, a doctor who works at the same hospital where I practice came by to say hello, and I noticed he had lost some weight. When I inquired about his weight loss, he said that he had decided to do something to get rid of the extra pounds, but when I asked him what he was doing, he seemed a little hesitant to discuss what he had done. This is one of the worst things to tell someone like me because I'm kind of curious about all things I can't easily explain. How does a highly conservative doctor (yes, I'm also a little judgmental) make such an effective and rapid change in weight...and why did I feel like I was prying the method(s) out of him? He knows me well enough to say that I'm kind of a data addict and that I respect efforts that attempt to prove points by evidence-based information, so instead of telling me outright what he did, he referred me to a book (he even gave me a copy, perhaps because I'm also cheap) and said I needed to read it if I wanted to find out what he did and was continuing to do. I was hooked.
The China Study and the basics of nutrition
The book was one I would never choose to read on my own. The title was unattractive to me, and the purported subject matter was one that I have had little interest in exploring. Perhaps because as a medical doctor, I and many others have experienced little or no training in the subject and most of us consider the information about the subject as the purview of other professionals. The book is titled The China Study, and it was written by T. C. Campbell and T. M. Campbell. Its subject is nutrition, the subject matter best left to professional nutritionists, in the opinion of myself and many others...so I thought.
The book is the summation of the lead author's lifetime journey through academia, which was and is focused on scientific studies related to nutrition. OK, it sounds boring. However, the authors have cleverly woven a life story about change, personal conflict, academic pressures, business interests, government regulations, and personality clashes, all linked to nutrition. To do that and present data to support many of the turning points involved in his life is a remarkable accomplishment to me because it held my interest.
More important perhaps than holding a reader's interest, the book made me rethink what I know about nutrition and its potential impact upon my family members, friends, and my patients' health. I decided to first go back to the basics, which to me helps clarify subjects; that basic point is to define terms that often have several meanings.
What is a 'diet?'
There is a lot of confusion and much advice about what to eat and what not to eat in order to have a healthy diet. But first, what is a diet, anyway? The term diet as defined by several dictionaries is supposed to mean the usual or customary intake of food and drink by people or animals. A secondary meaning is a regulated or prescribed intake of food and drink for medical or cosmetic (for example, weight loss) purposes. The first definition does not imply that someone's food and drink intake is healthy; it simply means a person's diet is what they normally eat and drink. However, the second definition clearly implies that a diet is regulated or prescribed for specific reasons that are often health related.
Consequently, it is fair to state that everyone has or "is on" a diet, but clearly not everyone's diet fits the second meaning. In my view, the second "diet" definition suggests that sometimes a person's customary intake needs to be regulated or prescribed for specific purposes, the first of which is medical. Many doctors (and patients) don't or won't like the sound of that. Why? It implies that someone (the doctor) knows what is medically best for someone else (the patient) to eat and drink.
How should doctors give dietary advice?
My experience has led me to believe that diet (food and drink intake) is to most people a very sensitive, complex, and personal decision. Much of our experience with foods and drink are based on family experience, but individual decisions about taste, consistency, and even socialization and emotion can play a significant role in our diet (the first meaning of the word). Most people do not want anyone to "intrude" on basic aspects of their life and lifestyle. If doctors do not see gross lifestyle "errors" like the diabetic who has consistently high blood sugar levels because the patient is still eating foods high in sugar or patients with high blood cholesterol levels who still eat a steak and egg meal frequently, doctors seldom prescribe a diet to lower these levels. The doctors usually prescribe medications and simply suggest that the patients alter their diet. Some may refer the individuals to a "dietary consultant" and simply avoid the potential "intrusion." What data do I have to back up these statements? None of my own; the statements are simply drawn from my experiences and observations, so at best they are anecdotal. Others may not agree if they have had different experiences.
What's the problem with the typical U.S. diet?
Is there a problem with our so-called normal diet, and if so, what should we as both doctors and patients do about it? By "our diet," I mean the usual diet for most people in the U.S. First, is there a problem with our diet? If the incidence of cardiac problems, obesity, diabetes, and other diseases are related to our U.S. diet, then it is likely there is a problem. In the book, The China Study, data is presented that suggests strong relations exist between what we normally eat in the U.S. and the occurrence of these diseases. Even without stating the same thing about the U.S. diet, some physicians suggest that patients with these problems cut back on the volume of food intake, get more exercise, avoid high cholesterol-containing foods, reduce salt intake, and eat more fiber. The book authors go much further and suggest several approaches to not only improve the U.S. diet, but to establish a routine U.S. diet that will help prevent, and in some cases, reverse damage caused by several of these diseases. In contrast to many nutrition publications, claims are backed up by references in the medical and nutritional literature, not by opinion or belief, but actual data. Although different investigators may interpret or criticize the collected data, they, too need to provide some basis for their interpretation and critique. So as doctors and patients, what should we do if we accept the premise that our normal U.S. diet has problems? The answer seems simple; address or fix the problems.
What are the problems? Upon opening almost any magazine or watch a TV talk show, usually an article or individual has a presentation about what and what not to eat. Many will say to increase protein and reduce carbohydrates, while others will say the opposite; some say coffee is great, others warn about the dangers of caffeine in coffee. The lists of items can go on and on. Most articles present little or no data to back up their conclusions. In contrast, the book's authors present data to define problems with the U.S. diet (for example, too much animal-based protein and fat), then present how to address the problem and finally present evidence (yes, data again) how this stated problem can be effected by changes in the U.S. diet.
Diet guidelines almost anyone can follow
I apologize for dragging you in with a teasing introduction that some readers will think is grossly unfair, because I haven't yet said what or what not to eat. My doctor friend who hooked me into this subject has not apologized for his trickery and has no guilty feelings (in fact, I think he is quietly chuckling to himself about his devious methods). However, I choose to take the high moral ground and at least summarize to readers what the authors conclude to eat and not to eat, to back my apology with some substance. This summary is data based from the book:
- Eat lots of different types of fruit that are unprocessed (no, strawberry Pop-Tarts do not fit in this category).
- Eat many types of vegetables (Popeye was right, spinach is a great food).
- Eat less (but maybe eat some) fish, vegetable oils, and few refined carbohydrates (Yes, it means to cut back or cut out eating candy and cakes).
- Avoid meats and dairy (this last category is the one that is the most controversial).
Yes, I know that many readers may still feel I cheated them about what to eat and what not to eat. For example, I have not commented on many details about how much to eat, how to prepare healthy meals, what should people eat if they have a specific disease, should pregnant females and children follow the China Study diet, and numerous other questions. Many specific questions are put forth and then answered by the authors, but this article is about long enough, so I choose to refer the readers to the book for a number of specific answers. Finally, many readers may wonder if, in my view, I agree with all of what the authors conclude. I cannot say that I do; I am still processing their conclusions and data and I have many unanswered questions. However, I would recommend any book that makes one think over how they approach a basic aspect of one's life, food, and drink. For those of you who made it this far in the article and vow never to read another article about nutrition or to read this book, I have good news. The China Study book has been made into a documentary film titled Forks Over Knives released in 2011. If nothing else, the movie likely will be an interesting subject to discuss over a meal.
Medically reviewed by John A. Daller, MD; American Board of Surgery with subspecialty certification in surgical critical care
Campbell, T.C., and T.M. Campbell. The China Study. Dallas, TX: Benbella Books, 2006.
Esselstyn, Jr., C. B. "Is the Present Therapy for Coronary Artery Disease the Radical Mastectomy of the Twenty-First Century?" The Amer. J. Cardiol. 106.6 (2010): 902-904.
Forks Over Knives, Dir. Lee Fulkerson. Based on the book The China Study by T.C. Campbell and T.M. Campbell. Monica Beach Media, 2010.