The Digestive System
Herbal medicine is uniquely suited for the treatment of illness of the digestive system. Throughout the natural world food is medicine, and the same concept applies to herbs — the ultimate medicinal food.
Much of the digestive system illness in our society is simply due to abuse. Today’s average Western diet includes a preponderance of overly processed foods, a high proportion of chemical additives, and the direct chemical irritation of alcohol, carbonated drinks, and tobacco. In this context it is easy to see why herbal remedies are so helpful in healing digestive problems; the soothing of demulcents, healing of astringents, and general toning of bitters do much to reverse the damage we do every day.
The digestive system is a series of hollow organs joined in a long, twisting tube — known as the alimentary canal — from the mouth to the anus. Inside the tube is a lining called the mucosa, which in the mouth, stomach, and small intestine contains glands that produce digestive juices. The liver and the pancreas are also part of the system, producing juices that reach the intestine through small tubes.
The food we eat is not in a form that the body can use as nourishment. It must be broken down into smaller molecules of nutrients that the blood can absorb and carry to the cells of the body. Digestion breaks down food and drink into their smallest parts so that the body can use them to build and nourish cells and to provide energy. The process, which begins in the mouth with chewing and swallowing and is completed in the small intestine, involves the mixing of food, its movement through the digestive tract, and the chemical breakdown of its large molecules into smaller molecules. The chemical process varies somewhat for different kinds of food.
The digestive system’s hollow organs contain muscles that enable their walls to move. This involuntary movement, called peristalsis, not only forces the contents forward but also mixes them. When we swallow, peristalsis begins. The muscles then contract and narrow, propelling the food particles and fluid down the length of the alimentary canal in slow waves.
The esophagus connects the throat above with the stomach below. At the junction of the esophagus and stomach, a ringlike valve closes the passage between the two organs. As the food travels down the esophagus and approaches the closed ring, the surrounding muscles relax and allow the food to pass through.
The food then enters the stomach, which performs several functions. The stomach stores the swallowed food and liquid and produces digestive juices. Muscle action in the lower part of the stomach mixes the contents of the stomach. Finally, the stomach slowly empties its contents into the small intestine. Several factors affect this emptying, including the nature of the food and the degree of muscle action of the emptying stomach and the small intestine. As the food is digested in the small intestine and dissolved by the juices from the pancreas, liver, and intestine, muscle action continues to mix the contents of the intestine and push them forward.
Finally, all of the digested nutrients are absorbed though the intestinal walls. The waste products of this process include undigested parts of the food, known as fiber, and older cells that have been shed from the mucosa. These materials are propelled into the colon, where they remain, usually for a day or two, until they are expelled as feces through a bowel movement.
The production of digestive juices is a vital function of the digestive system. The salivary glands in the mouth start that process. An enzyme in saliva begins to digest the starch in food into smaller molecules. The next set of glands involved in digestion is in the lining of the stomach. These gastric glands produce stomach acid and an enzyme that digests protein. One of the unsolved puzzles of the digestive system is why the acid juice of the stomach does not dissolve the tissue of the stomach itself.
After the stomach empties the food and its juice into the small intestine, the juices of two other digestive organs, the pancreas and the liver, mix with the food to continue the digestion process. The pancreas produces an array of enzymes that break down carbohydrates, fat, and protein in food. Other enzymes involved at this stage of the process come from glands in the wall of the small intestine.
The liver produces bile, which is stored in the gallbladder until needed. At mealtime, the bile is squeezed out of the gallbladder through the bile ducts and into the intestine and mixes with the fat in our food. The bile acids dissolve the fat into the watery contents of the intestine, acting much like detergents that dissolve grease in water. Enzymes from the pancreas and the lining of the intestine digest the dissolved fat.
Herbs’ unique healing properties have a direct effect upon the lining of the alimentary canal. The herbs’ constituents can directly touch the cells of the mucosa without first having to be assimilated into the bloodstream, travel through the liver, and make their way through the rest of the body before entering the cells from the blood. Thus, the body can rapidly reap the benefits of constituents that might reduce inflammation, relax muscles, combat bacterial infection, or promote the healing of wounds.
However, as with all true healing, any potential “cure” lies beyond the range of medicines, be they herbal or pharmaceutical. The healing process must involve a lifestyle change that includes a healthy diet and reduction of tress. Herbal medicine can bring about dramatic improvements in even profound digestive system problems, but you won’t experience its full benefits unless you also follow a healthy lifestyle. The long-term maintenance of the benefits you get from herbs lies in your hands alone.
Europeans have long used herbs to aid digestion. From culinary herbs such as rosemary to “medicinal” alcohols such as vermouth or Chartreuse, Europeans use these remedies in large quantities. The very name “vermouth” is derived from the bitter remedy wormwood, whose name in German is wermut. In official pharmacopoeias, such as the U.S. Pharmacopoeia (USP) and British Pharmacopoeia (BP), herbs have the strongest foothold as therapeutic agents in the categories o digestive bitters, carminatives, and laxatives of varying strengths.
In the hands of a skilled herbalist, much can be achieved therapeutically. While each individual with a gastric ulcer, for example, will have his or her own set of unique causes, we can identify a treatment based on our knowledge of the different herbs.
Used holistically, herbal medicine offers specific remedies for particular pathological syndromes as well as preventive tonics and normalizers. Treating the problem within this context of general nurturing speeds improvement and reestablishes health and harmony.
Ideally, we want to preserve health and maintain wellness rather than treat illness. Of course, there is much more to preventive medicine than simply taking “stuff” in the form of a medicinal plant or chemical drug. The World Health Organization (WHO) has a wonderful definition of health that helps put this idea in perspective: “Health is a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity.”
Any attempt to promote wellness and prevent the development of disease must address the various complex factors that WHO identified. While this book cannot explore all of these factors in depth, it will help you identify a number of risk factors to minimize as well as positive actions to emphasize.
By far the most important contribution we can make to the health of our digestive systems is the food we eat. Digestion makes all of the different nutrients available to the rest of the body. The human body requires over 40 nutrients for energy, growth, and tissue maintenance. All of these nutrients are found in a well-rounded diet, and many of them are found both in plants traditionally eaten as grains, vegetables, or fruits and those used as medicinal herbs. Often the only fundamental difference between a sale vegetable and a medicinal herb is that the vegetable tastes better!
Remember: Eating a balanced diet is a major factor in a healthy lifestyle. Using medicinal herbs does not eliminate the need for such a diet.
The official dietary guidelines, established jointly by the U.S. Departments of Agriculture and Health and Human and Services, include seven basic recommendations:
If you consistently eat a well-balanced diet of fresh fruits, vegetables, grains, and some animal protein, you probably won’t require a nutritional supplement. Multinutrient supplements offer insurance for those times when eating well is a challenge, and they can be indispensable during pregnancy and times of disease, injury, and extreme stress or physical exertion.
Water, the most plentiful component in the body, is crucial to our survival. It is the medium for such bodily fluids as blood and lymph, and it transports nutrients into cells and carries out waste products and toxins. Most of the material absorbed from the cavity of the small intestine is water in which salt is dissolved. In a healthy adult, more than a gallon of water containing over an ounce of salt is absorbed from the intestine every 24 hours.
Carbohydrates, proteins, and fats — a dietary group known as macronutrients — provide fuel for the body in the form of calories. Carbohydrates, the body’s main energy source, are divided into two types: simple carbohydrates, which are sugars; and complex carbohydrates, which are made up of sugars, fiber, and starches — such as those found in potatoes and bread. The average American adult eats about 1⁄2 pound of carbohydrates each day. Many of these carbohydrates consist of starch, which the body can digest, and fiber, which it can’t digest. Enzymes in the saliva, in pancreatic juices, and in the lining of the small intestine break down the digestible carbohydrates into simpler molecules.
Proteins support tissue growth and repair and help produce antibodies, hormones, and enzymes — which are essential for all chemical reactions in the body. Dietary protein sources include dairy products, beans, eggs, fish, meat, and nuts. An enzyme in the juice of the stomach starts the digestion of protein. Digestion is completed in the small intestine, where several enzymes in pancreatic juices and in the intestinal lining break huge protein molecules into small molecules called amino acids. These small molecules can be absorbed through the small intestine into the blood.
Dietary fat protects internal organs, provides energy, insulates against cold, and helps the body absorb certain vitamins. There are three kinds of fats: saturated, found in meat, dairy food, and coconut oil; monounsaturated, found in olive, peanut, and canola oils; and polyunsaturated, found in corn, cottonseed, safflower, soy, and sunflower oils. Bile acids produced by the liver dissolve fat in the watery content of the intestinal canal, allowing enzymes to break the large fat molecules into small molecules — some of which are fatty acids and cholesterol. In the mucosa, the small molecules are formed back into large molecules, most of which pass into the lymph vessels near the intestine.
Your diet also supplies the important micronutrients we call vitamins and minerals. They are needed only in trace amounts, but the absence or deficiency of just one vitamin or mineral can cause major illness.
Vitamins and minerals are absorbed from the small intestine and passed into the bloodstream. There are two different types of vitamins, classified by the fluid in which they are dissolved: Water-soluble vitamins include all of the B vitamins and vitamin C, while the fat-soluble vitamins are A, D, E, and K.
Minerals fulfill a plethora of specific biochemical roles in the body, but they are especially important as essential components of enzymes and coenzymes. Without a balanced intake of minerals, the various digestive functions of the gut would be impaired.
Dietary fiber is largely composed of the cellulose-like components of plant cell walls. Its composition is a complex of constituents and varies from plant to plant. This fiber is the part of fruits, vegetables, and grains that the body cannot digest. Soluble fiber dissolves easily in water, taking on a soft, jellylike texture in the intestines. Insoluble fiber passes almost unchanged through the intestines. Both kinds of fiber help make stools soft and easy to pass, preventing constipation. Since supplements lack this natural complexity, they cannot replace a varied diet rich in high-fiber foods.
Never underestimate the importance of dietary fiber. A high-fiber diet reduces the risks of various gastrointestinal problems and even promotes cardiovascular health. Here are some of fiber’s benefits:
There is an abundance of research on the association between fiber and human health, and a number of conditions have been linked to low-fiber diets. In contrast, a high-fiber diet is associated with a decreased incidence of most of the degenerative diseases of Western society. Fiber alone is not a cure-all, but high-fiber diets also tend to be high in other nutrients — most of which are deficient in the “normal” Western diet.
The American Dietetic Association recommends we eat 20 to 35 grams of fiber each day. The best source of dietary fiber is whole foods, although specific types of fibers have their use in the treatment phase of specific diseases. There is no substitute for a healthy diet — that is, a diet composed of foods in a form as close to their original form as possible.
Fruits | ||
Food | Serving Size | Grams of Fiber |
Apple (with skin) | 1 medium | 3.5 |
Banana | 1 medium | 2.4 |
Cantaloupe | 1⁄4 melon | 1 |
Cherries, sweet | 10 | 1.2 |
Grapefruit | 1⁄2 medium | 1.6 |
Orange | 1 medium | 2.6 |
Peach (with skin) | 1 medium | 1.9 |
Pear (with skin) | 1⁄2 large | 3.1 |
Prunes | 3 | 3 |
Raisins | 1⁄4 cup | 3.1 |
Raspberries | 1⁄2 cup | 3.1 |
Strawberries | 1 cup | 3 |
Vegetables, Raw | ||
Food | Serving Size | Grams of Fiber |
Bean sprouts | 1⁄2 cup | 1.5 |
Celery, diced | 1⁄2 cup | 1.1 |
Cucumber | 1⁄2 cup | 0.4 |
Lettuce | 1 cup | 0.9 |
Mushrooms | 1⁄2 cup | 1.5 |
Pepper, green | 1⁄2 cup | 0.5 |
Spinach | 1 cup | 1.2 |
Tomato | 1 medium | 1.5 |
Vegetables, Cooked | ||
Food | Serving Size | Grams of Fiber |
Asparagus, cut | 1 cup | 2 |
Beans, green | 1 cup | 3.2 |
Broccoli | 1 cup | 4.4 |
Brussels sprouts | 1 cup | 4.6 |
Cabbage, red | 1 cup | 2.8 |
Carrots | 1 cup | 4.6 |
Cauliflower | 1 cup | 2.2 |
Corn | 1⁄2 cup | 2.9 |
Kale | 1 cup | 2.8 |
Parsnip | 1 cup | 5.4 |
Potato (with skin) | 1 medium | 2.5 |
Potato (without skin) | 1 medium | 1.4 |
Spinach | 1 cup | 4.2 |
Sweet potatoes | 1 medium | 3.4 |
Zucchini | 1 cup | 3.6 |
Legumes | ||
Food | Serving Size | Grams of Fiber |
Baked beans | 1⁄2 cup | 8.8 |
Dried peas, cooked | 1⁄2 cup | 4.7 |
Kidney beans, cooked | 1⁄2 cup | 7.3 |
Lentils, cooked | 1⁄2 cup | 3.7 |
Lima beans, cooked | 1⁄2 cup | 4.5 |
Navy beans, cooked | 1⁄2 cup | 6 |
Breads, Flour, Pastas, and Rice | ||
Food | Serving Size | Grams of Fiber |
Bran muffins | 1 muffin | 2.5 |
Bread, white | 1 slice | 0.4 |
Bread, whole wheat | 1 slice | 1.4 |
Crisp bread, rye | 2 crackers | 2 |
Rice, brown, cooked | 1⁄2 cup | 1 |
Rice, white, cooked | 1⁄2 cup | 0.2 |
Spaghetti, regular, cooked | 1⁄2 cup | 1.1 |
Spaghetti, whole wheat, cooked | 1⁄2 cup | 3.9 |
Breakfast Cereals | ||
Food | Serving Size | Grams of Fiber |
All-Bran | 1⁄3 cup | 8.5 |
Bran Chex | 2⁄3 cup | 4.6 |
Corn Bran | 2⁄3 cup | 5.4 |
Cornflakes | 11⁄4 cup | 0.3 |
Grape-Nuts | 1⁄4 cup | 1.4 |
Oatmeal | 3⁄4 cup | 1.6 |
Raisin Bran | 2⁄3 cup | 4 |
Shredded Wheat | 2⁄3 cup | 2.6 |
Nuts | ||
Food | Serving Size | Grams of Fiber |
Almonds | 10 nuts | 1.1 |
Filberts | 10 nuts | 0.8 |
Peanuts | 10 nuts | 1.4 |
Murray, Michael T., N.D. The Encyclopedia of Nutritional Supplements, © 1996 by Michael T. Murray. Reprint by permission of Prima Publishing, Roseville, CA. | ||
Fiber can both help prevent and improve these conditions:
Cardiovascular conditions: cerebrovascular disease, deep vein thrombosis, hypertension, ischemic heart disease, pulmonary embolism, varicose veins
Colon conditions: appendicitis, colon cancer, constipation, Crohn’s disease, diverticulitis, diverticulosis, hemorrhoids, irritable bowel syndrome, ulcerative colitis
Metabolic conditions: diabetes, gallstones, gout, kidney stones, obesity
Other conditions: autoimmune disorders, dental caries, dermotological conditions, multiple sclerosis, pernicious anemia, thyrotoxicosis
In addition to causing heart and lung diseases, tobacco is responsible for changes in the digestive system. Smoking impacts all parts of the digestive system, contributing to such common problems as heartburn and peptic ulcers. Increases in the risk of Crohn’s disease and possibly gallstone have also been connected with tobacco consumption.
Most of these effects on the digestive system appear to be of short duration, but a good piece of advice for digestive well-being is stop smoking!
Heartburn occurs when acidic juices from the stomach splash into the esophagus. Normally, a muscular valve at the lower end of the esophagus keeps the acid solution in the stomach. Smoking weakens this valve, allowing the stomach contents to flow backward into the esophagus. Smoking can also directly injure the esophagus, making it more prone to damage from refluxed material.
A peptic ulcer is an open sore in the lining of the stomach or duodenum, the first part of the small intestine. The exact cause of ulcers is not known, but the main cause is suspected to be bacterial infection. Some ulcers are caused by long-term use of nonsteroidal anti-inflammatory agents (NSAIDs), such as aspirin and ibuprofen. Occasionally, cancerous tumors in the stomach or pancreas can also cause ulcers. The 1989 Surgeon General’s report stated that ulcers are more likely to occur, less likely to heal, and more likely to cause death in smokers than in nonsmokers.
Among the liver’s multitude of vital functions is the processing of drugs, alcohol, and other toxins to remove them from the body. Smoking alters the liver’s ability to handle these substances. Some research also suggests that smoking can aggravate the course of live disease caused by excessive alcohol intake.
A severe gastrointestinal disorder that has no known cause, Crohn’s disease produces inflammation deep in the lining of the intestine. The disease, symptoms of which are pain and diarrhea, usually affects the small intestine, but it can occur anywhere in the digestive tract. Both current and former smokers have a higher risk than nonsmokers of developing Crohn’s disease. Smoking is associated with a higher rate of relapse, repeat surgery, and immune-suppressive treatment.