Indigestion and irritable bowel syndrome are modern phenomena
Our ancestors did not eat the way we do. Their diets were composed of one or two foods at a time as they came across them, with many meals consisting of nothing but animal protein or fruit or roots with herbs. With the advent of agriculture, a more varied diet became available. However, vegetables and fruits were still generally available only in their season, except for a few root vegetables that could be stored. The food processing, we take for granted today had not yet been invented, and processed carbohydrates were not a part of the diet. Rolaids hadn't been invented either, and it appears that our ancestors did not suffer from the digestive problems so prevalent in modern times. Dr. William Hay is well-known for his research into this poorly- understood (and poorly followed!) health opportunity.
Principles of Digestion
The theory of food combining is based on the idea that good health results from a body that is slightly alkaline and stays in line with the basic principles of digestion. It is a scientifically based system of selecting foods that are compatible from all that are available. By grouping the right foods together people can be assured of effortless digestion and more complete assimilation and use of nutrients by the body. When foods are correctly combined, nutrients from them can be used to their fullest extent to promote good health.
Digestion is facilitated by juices and enzymes produced in response to a cue from the particular food that has been eaten. The juices can be alkaline or acid depending on the particular enzymes they contain. Carbohydrate foods stimulate the secretion of enzymes made specifically to break down carbohydrates, while protein foods require the secretion of enzymes made specifically to break down protein. Fats too have specific enzymes needs to facilitate their breakdown. These enzymes are active only in a suitable media with well-defined acid-alkaline ranges. They are destroyed by variation in those ranges.
Let me give you a few examples. The salivary enzyme, amylase, is produced in response to eating carbohydrates. Its job is to break down carbohydrates for digestion. Amylase is only active in an alkaline medium and is destroyed by a mildly acidic environment. The gastric enzyme, pepsin, is produced in response to eating protein, and its job is to break down protein for digestion. Pepsin is only active in an acid medium and is destroyed in an alkaline environment. While the body will produce juices and enzymes specific to any type of food that has been eaten, it is unable to do so efficiently when a variety of foods are eaten together. The result? Digestive distress!
The body gets enzymes for digestion both from food itself (if the food is raw or only cooked at low temperatures) and from a supply the body makes itself. Many people struggle with digestion later in life because our body’s natural enzyme production diminishes as we age. A lack of sufficient enzymes can also cause great GI distress. You can purchase digestive enzyme supplements to support your own supply.
Avoid Eating Heavy Protein and Carbohydrates in the Same Meal
When foods are improperly combined, fermentation in the digestive tract and digestive distress are the likely outcome. When foods eaten at a meal are of the same type, there is no fermentation and proper digestion is allowed to take place. The best way to avoid fermentation is to avoid mixing high-protein foods with high-carbohydrate foods. Breakdown of protein requires an acidic medium, and digestion of protein dense animal products requires high levels of hydrochloric acid. Thus, high carbohydrate foods that have been mixed with high protein foods will not digest but will sit there fermenting, producing indigestion, bloating and gas. Furthermore, this fermentation of carbohydrates will inhibit the digestion of the protein; thus, more gas, bloating and discomfort will be produced.
This principle makes the typical American meal, composed of a large hunk of meat along with potatoes and bread, a recipe for digestive disaster. Research has found that most protein foods are best digested when accompanied by fresh non-starchy vegetables, especially a green salad. Non-Starchy Vegetables include Leafy greens, broccoli, asparagus, cauliflower, carrots, bok choy, cabbage, celery, lettuces, green beans, garlic, fennel, onions, chives, turnips, sprouts, red radish, yellow squash, zucchini, cucumber, and beets. Other concentrated protein foods like nuts and seeds combine well with acidic fruits such as oranges, lemons, tomatoes, pineapples, blackberries, or strawberries. The vitamin C in these fruits’ aids digestion of the mixture.
Avoid Eating Carbohydrates and Acidic Fruits at the Same Time
Carbohydrate digestion begins in the mouth. There is an enzyme in saliva that begins the breakdown of starch-concentrated foods and does the important job of converting complex starch molecules into more simple sugars. To work efficiently, the enzyme requires a neutral or slightly alkaline medium, the natural condition found in the mouth. When acidic foods are eaten, the action of the enzyme needed to break down starch is halted because the medium needed has been altered. Thus (like protein in the first example above) acid fruits should not be eaten at the same meal as sweet fruits (such as pears, peaches, and bananas), grains, starchy vegetables, or other starches. This combination is what makes pizza, spaghetti, and steak-and-potatoes-and-bread combinations so bloating. Those with sensitive digestive systems may experience bloating with similar combinations of less-heavy protein such as cereal-and-milk, eggs-and-toast, sandwiches with meat and cheese.
In summary, try to consume foods needing an acidic environment at once (e.g. meats, nuts, acidic fruits) and foods needing an alkaline environment at once (e.g. grains, starches, most vegetables). Non-starchy and sea vegetables and fermented drinks and fermented vegetables go well with either category. All other fruits should be eaten all on their own.
There are many other concepts of food combining based on principles of optimal digestion. To learn more, see the full article: By Barbara Minton, Natural Health Editor, Natural News newsletter, 2/17/09. http://www.naturalnews.com/025651.html
This on-line article is also quite helpful:
Other more In-Depth references if you have a passion for the topic: Grant, Doris, Joice, Jean, Food Combining for Health. Food Combining, The Internet Health Library 2000. Food Combining Diet for Weight Loss, healthylifestyle.com.