Medical anthropology can be defined as the study of diverse healing or curing traditions, including practitioners, methodology, ideology/philosophy of cause and effect, as well as cultural behaviors or traditions that lead to or detract from individual and social health. Also included in this definition is our knowledge and speculation about dietary habits, including herbs, of our ancient ancestors. Clinical anthropology would be the application of this comparative knowledge.

Antacids, both over the counter and prescribed, are widely used in North America. The question, then, is, "Why?" Is the digestive failure, as evidenced by the many ads on television caused by bad genes or cultural eating patterns of long standing? Yes, bad genes may play a part in a small number of cases. Trauma could also be a factor. However, most digestive failure appears to be a product of cultural eating habits. The FDA and the USDA suggest that you eat balanced meals, that is to say, one should consume proteins, carbohydrates, and fats at the same meal for ultimate health. This is the food pyramid found on bread wrappers, cracker boxes, and so on, which suggests, that the contents are wholesome and nutritious. For one thing, most breads and crackers are made from fractionated grains, where, during processing, most of the nutrients are removed and only a small number are replaced. This is called "enriched" by the manufacturers, allowed by the FDA, but misleading.

Moreover, eating a balanced meal invites digestive failure. The reason for this has to do with gut morphology and where and how each food group is digested. Before getting to the specifics, it is important to understand the evolutionary precedents of gut morphology.

Obviously we do not have remains of ancient stomachs or intestines with which to compare modern gut form and function. However, we can draw inferences from three sources: (1) dental morphology (the structure of teeth); (2) how food was available to our ancestors; and (3) analysis of coprolites (fossilized fecal material).

Dental Morphology

Many of us reside with carnivores, that is, the family cat. The tooth structures of a cat are designed as weapons, to secure prey that rejects being eaten, and to shear meat and crush bone. Here is a picture of cat dentition (Drawing 1).

As you can appreciate, this is specialized dentition. What is equally interesting is that, in the average cat diet in North America, there is a great deal of vegetable material often eaten at the same time as the dense protein. Read the contents on the canned, and especially the dried foods, the kibble most cats eat. Cats (and dogs, I might add) have very similar illnesses to those of their human caretakers. Is there a connection here with their culturally based eating habits, illnesses, and ultimate longevity? Yes, there is.

Dentition of Our Ancient Ancestors

The Australopithecines existed between 4-5 million years ago. Dentition is a "conservative" trait. In other words, our teeth have not changed much over the past few million years. This is why they are so useful in determining relationships between species and diet.

As illustrated in Klein (1999:204), human teeth are very similar to Australopithecine teeth in that there are incisors, canines, premolars, and molars. There is even a comparison with chimpanzee dentition to show the similarities and dissimilarities. One difference we see with our afarensis ancestors is something called a diastema, which is an occlusal gap for large protruding canine teeth. The gap allows the jaw to close, and, in doing so, acts as a pair of scissors. These teeth were weapons, as the rest of the teeth do not resemble those of carnivores like our familiar house cat.

With the africanus, robustus, and human, there is no diastema. The canines are short indicating that we do not use our teeth as weapons. Our teeth, as well as those of our ancient ancestors indicate an adaptation to a varied diet of vegetables, fruits, nuts, insects, and a small amount of meat. There is no evidence of large game hunting until 350,000 years ago (Bower 1997:134), and it was probably supplemental to a mainly scavenging mode of existence.

According to Chivers (1994:64), "Humans are on the inner edge of the faunivore cluster, showing the distinctive adaptations of their guts for meat eating, or for some other rapidly digested foods, in contrast to the frugivorous apes (and monkeys)." In other words, we are adapted to eat meat, but everything else as well; we are not specialized meat eaters as are cats. Moreover, adapting to a varied diet means that we derive our nutrients from a wide variety of sources. Keep this point in mind.

When we get up in the morning most of us have a virtual smorgasbord available in our refrigerators and cupboards. We can consume eggs, bread, bacon, sausage, cereals, milk, fruits--just about anything your heart desires. And, of course, we cook our food; we boil, broil, fry, microwave, steam, and barbecue. Much of this food is already processed and cooking can be seen as further processing. And, being good cultural carriers, we eat according to the USDA pyramid.

But, is this the way our ancestors ate 4 million years ago or even 10,000 years ago? Did our ancestors follow the consumption advise of the USDA, that is, eat "balanced meals" composed of complex carbohydrates (about 74 percent of intake), protein (20 percent), and oil/fats (6 percent)? Some of you may be thinking, "Well, haven’t our guts evolved since then to eat in this fashion?" The answer to this is, for the most part, no. Nutritional deficiencies of an extreme nature weed out individuals before childbearing age unless they are of a genotype that can survive under those conditions. Two examples of this are the Pima Indians who are designed to survive with a calorie deficient diet, and the Eskimo or Inuit who have adapted to a high protein/fat diet. Once the Pima Indians begin consuming the average North American diet they become diabetic (see Lappe 1994); the Inuit, once subject to a high carbohydrate diet, experience periodontal diseases, otitis media, an increase in diabetes, and a decreased life span (see Overfield 1995). The nutritional deficiencies in our country, for most people, are of a different type which result in major health problems that often do not manifest themselves until after child bearing (after about 35 years of age).

So, how and what did our ancestor eat? Diagram 3 will serve to visually display a typical day in the life of our ancestors.

As you can see, and, the pattern of movement is hypothetical, food sources of various types are located in time and space. For any of you who have a garden you know that, left unattended, certain plants encroach on others and, if they do not outright kill them, hinder their ability to grow. Invasive plants will take over an area until they run into other plants which either out grow them or release chemicals in the air or soil that inhibit growth or kill. Seven years ago I planted some pennyroyal (Mentha pulegium) as a flea repellent for my cats (the dried, powdered leaves are sprinkled on the cats--the fleas do not like this!). Five years ago, I planted some Valerian officinalis next to the pennyroyal. By the end of the summer, the pennyroyal migrated about ten feet away where it seemed to flourish, but, by the end of the next summer, the pennyroyal died off. Although this is a tender perennial, the weather conditions in Sacramento are not extreme enough to kill this plant. Plants, in the wild, grow and evolve in accordance with the presence of other plants, soil conditions, insects, and other grazing animals (see Fritz and Simms 1992). The only reason that you can have a smorgasbord in your back yard is because you manage the plants. Left on their own, plants have another agenda.

Our ancient ancestors had to work for their food; they did not eat in a smorgasbord fashion combing all the food groups at one setting. They would arise in the morning and obtain whatever food was close by, perhaps some fruit. Next, they would move to another food source, which would require time and energy, and then move to another, and so on. As an aside, and considering John's (1999:27-50) suggestions about oxidative stress and the need for antioxidants from plants, our color vision may have aided us greatly in picking out plants visually through color discrimination. That is to say, the darker green plants usually contain richer sources of phytochemicals.

In any event, foods were consumed, in most cases, in a singular fashion, that is, fruit, then another type of food, and so on. Trigg et al.(1994:217), in their analysis of coprolite remains from Bat Cave, New Mexico, state, "One of the most important findings of this research is the characterization of plant consumption at Bat Cave. The macroremains suggested that meals had consisted of combinations of subsistence items, with one food type dominating each sample." The "combinations of subsistence items" were vegetable. Although the remains date to AD 200-1000, far shy of 4-5 million years ago, the time period I believe that our gut morphology was in place, this evidence is suggestive of a foraging/consumption behavior in existence until very recent times, that is, the advent of sedentary agriculture and a reduction of the number of plants utilized in the diet. I will return to this issue shortly.

During the course of a day, then, our ancient ancestors would be exposed to many different foods, existing in micro-environments, much of it vegetable/carbohydrate. Once again, these foods were located in time and space. Moreover, none of this food was processed, that is, milled, cooked, boiled, and so on, except by the workings of the mouth and the rest of the digestive system, and certainly none of it was fractionated.

As Larsen States (1995:204), "The shift from foraging to farming led to a reduction in health status and well-being, an increase in physiological stress, a decline in nutrition, an increase in birthrate and population growth, and an alteration of activity types and work loads. Taken as a whole, then, the popular and scholarly perception that quality of life improved with the acquisition of agriculture is incorrect."

Consuming the Basic Food Groups at the same Meal

So, what does all this mean? If we have a digestive system adapted to eating one type of food and eating foods in a sequential fashion, what happens when we follow the advice of the USDA and eat balanced meals containing dense proteins (meat, fish, chicken, eggs) combined with dense carbohydrates (bread, pasta, rice, potato, vegetables) and fats? When protein enters the stomach, the hormone gastrin is released which causes the release of HCl, lowering the pH level to 2. This is necessary to begin the process of denaturing the protein and cleaving peptide bonds. However, when dense carbohydrates (fats are less of a problem) are added to the meal, they interfere with the activity of HCl and other acid enzymes for properly breaking down the protein. Further, the carbohydrates raise the pH level of the stomach contents and this signals the release of more HCl. However, the carbohydrates, once again, raise the pH level, and the process goes on and on leading to a burning sensation (gastritis), gas and bloating, and uncomfortable fullness. The protein, then, is not being digested.

But there is another issue. Residing in the stomach are a number of bacteria that have adapted to such a harsh environment. As Singleton and Sainsbury (1993:380) state, "In adult humans, most bacteria ingested with food (and oral bacteria swallowed with saliva) are normally killed by the acidity in the stomach; the stomach may thus be largely free of microorganisms, or may contain a sparse flora of e.g. viridans streptococci, lactobacilli, and Candida spp. (Larger numbers of organisms may occur in the stomach in cases of achlorhydria.)" "Achlorhydria" refers to an absence of HCl in the stomach. Now, keep in mind, that the elimination of bacteria by the HCl is conditional on the pH level, for, even though HCl is present, the pH must be at a low level, which becomes a problem when large amounts of dense carbohydrates are in the stomach with the dense protein.

Moreover, another bacteria has been found in the stomach and that is Helicobacter pylori, which has been associated with gastritis and ulcers and "is in a large number of human stomachs. It is found in all human populations and increases as we get older--at about the age of 50 at least half of the individuals studied have the bacterium, even without having an ulcer or gastritis" (Janowitz 1992:62). Although it is debatable that H. pylori causes ulcers, it is probably more of an opportunist presented with a satisfactory living environment mainly because of the "balanced" diets with which we subject the stomach.

A meal containing dense protein and dense carbohydrates will slow down if not halt protein digestion in the stomach. This gives the bacteria present an opportunity to putrefy the protein and ferment the carbohydrates. This results in a large amount of gas and "spoiled food," which, after several hours, moves into the duodenum. Secretin is then dumped which communicates with the pancreas causing the release of bicarbonate thus raising the pH. The food is then moved to the small intestine. The small intestine is designed as an alkaline environment were base enzymes break down the carbohydrates and fats and further work on amino acids (not putrefied proteins). Although Janowitz (1992:161) states that maldigestion of protein is rare, I question this conclusion. I suggest that it is quite common--all one has to do is examine the fecal remains after a "balanced" meal of dense protein and dense carbohydrates to find large amounts of putrefied protein; the putrid smell should be the first clue.

But what happens to this putrid protein once it enters the small intestine? One of the results is that it interferes with the digestion of the carbohydrates and fats. Another result is that the putrid protein acts as a wonderful breeding ground for the numerous bacteria residing in the small intestine, some of which can damage the intestinal lining (for example, enterobacteria like Escherichia coli, enteroviruses, protozoa, and yeasts). Irritable Bowel Syndrome and Crohn’s disease may be caused by opportunists created by this "balanced" diet, including lack of fiber (see Whittaker and Freeman 1993), as well as a lack of Lactobacillus strains of friendly bacteria.

A third consequence of having putrefied protein in the small intestine is the passage of small bits of protein through the intestine wall and into the blood stream. These are foreign proteins, which are attacked by the immune system. The results of this are allergies and arthritic conditions.

I see numerous patients with symptoms on long-term digestive failure. Keep in mind that digestive problems are systemic and they affect every cell in your body resulting in cardio-vascular problems, gallbladder and liver dysfunction, imbalance of neurochemistry leading to depression, as well as cancer, thyroid problem, and more. A primary step to the development and maintenance of health over time is to eat according to the design of our digestive system. What this means is that: (1) digestive problems (gas, heartburn, reflux, etc.) and (2) malabsorption of nutrients are less likely to occur if proteins are not eaten at the same time as carbohydrates. Fruit should likewise be eaten separately. This is certainly contrary to North American eating habits, from school lunches to fast foods, and certainly the meals prepared in most homes in America. Keep in mind that the USDA pyramid is not a statement about or concern with the physiological processing of food but is, instead, an alignment with existing cultural habits. Yes, we do need a certain amount of fat, carbohydrates, and protein (actually amino acids--your body does not really need dense protein in the form of meat, fish, chicken, or eggs), but, as I have explained above, to eat all the food groups together at the same meal invites digestive failure and chronic health issues as the years go by.

Patients, then, are informed about causes of digestive failure and how this may relate to their current symptoms (gastritis, reflux, skin problems, depression, and so on). The most difficult task is to keep the patient motivated long enough (often two or three months or more to clear up sever symptoms, i.e. fibromyalgia) so that they notice improvement. Those that stay with the program feel better, think clearer, manage their weight better, and, in most cases, the symptoms that brought them to my office are gone or greatly diminished.

Food sequencing alone will take the person a long way toward health. Other issues include adding fiber to the diet, avoiding fractionated foods (i.e. avoid white rice and enriched wheat products), and supplementation. For those interested, I can post a general procedure for fiber supplementation and vitamin, mineral, and fatty acid intake.

One final comment. Western biomedicine, with the exception of trauma medicine, is engaged in symptom suppression, which simply leads to other health problems over time. One of the goals of Medical Anthropology is an understanding of Western biomedical practices and philosophies. On the clinical side the goal is to more clearly establish cause and effect in health concerns. The symptom is not the cause of the problem only a signal that a problem exists, and to treat the symptom without addressing the cause is not the practice of health care. The suppression of symptoms, and assuming that the cause will go away, is a form of magical thinking, unscientific, and, in my opinion, irresponsible.

Bower, B. 1997. "German mine yields ancient hunting spears." Science news 151(9):134.

Chivers, D. 1994. "Diet and Guts." In Cambridge Encyclopedia of Human Evolution, ed. Steve Jones, Robert Martin, and David Pilbeam, New York: Cambridge University Press, 60-64.

Fritz, R. and Simms, E. 1992. Plant Resistance to Herbivores and Pathogens. Chicago: University of Chicago Press.

Janowitz, H. 1992. Indigestion. New York: Oxford University Press.

Johns, T. 1999. "The Chemical Ecology of Human Ingestive Behaviors." Annual Review of Anthropology, Vol. 28:27-50.

Klein, R. 1999. The Human Career: Human Biological and Cultural Origins, 2^nd edition. Chicago: University of Chicago Press.

Lappe, M. 1994. Evolutionary Medicine: Rethinking the Origins of Disease. San Francisco: Sierra Club Books.

Larsen, C. 1995. "Biological Changes in Human Populations with Agriculture." Annual Review of Anthropology, Vol. 24:185-213.

Overfield, T. 1995. Biologic Variation in Health and Illness: Race, Age, and Sex Differences. Boca Raton, Fl.: CRC Press.

Singleton, P. and Sainsbury, D. 1993. Dictionary of Microbiology and Molecular Biology, 2nd edition. New York: John Wiley & Sons.

Trigg, H., Ford, R., and Moore, J. 1994. "Coprolite Evidence for Prehistoric Foodstuffs, Condiments, and Medicines." In Eating on the Wild Side: The Pharmacologic, Ecologic, and Social Implications of Using Noncultigens, ed. Nina Etkin, Tucson: University of Arizona Press, 210-223.

Whittaker, J. and Freeman, H. 1993. "Fiber and Inflammatory Bowel Disease." In CRC Handbook of Dietary Fiber in Human Nutrition, 2nd edition, ed. G. Spiller, Boca Raton, Fl.: CRC Press.