When each nutrient from food is assimilated it has an acid or alkaline effect on the blood. The main elements that have acid effects are nitrogen, phosphorus, sulfur, and chlorine. The main elements that have alkaline effects are potassium, magnesium, calcium, sodium, and iron. We need all of these elements—both alkaline and acid—but their intake needs to be balanced. The ideal ratio of alkaline to acid is considered by some to be 4:1. Most people have various degrees of acidosis, which is said to cause negative health effects such as frequent colds, susceptibility to diseases, and slow recovery when sick. Alkalosis, on the other hand, is very uncommon and occurs primarily as a result of medical drugs or high use of stomach antacids.
It is important to realize that the acidity in this context is not related to the acidity of the food itself as measured with, say, litmus paper. For example, acid fruits such as grapefruit and lemon actually have an alkaline effect in the body. This seeming contradiction is resolved by realizing that citric acid (C6H8O7), tartaric acid (C4H6O6), and malic acid (C4H6O5), contained in citrus fruits, grapes, and apples, respectively, are ultimately metabolized into water (H2O) and carbon dioxide (CO2). Water, of course, is neutral, and though acidic when in solution, CO2 is readily eliminated via the lungs. Therefore, the three organic acids above and others such as and acetic (C2H4O2), carbonic (H2CO3), lactic (C3H6O3), etc., are disregarded when the acidity of a food is calculated.
The most acid foods are meats, eggs (especially the yolk), beans, peanuts. and white flour and rice. Alkaline foods are primarily fruits, vegetables, and soybeans (very alkaline).
One important consideration of acid and alkaline balance is its relationship to bone density and strength. Whenever we eat foods that are primarily acid, the elements of these foods are incorporated into the blood stream. There, the resulting acidic effect must be neutralized by the alkaline elements of the body to maintain what is a very strict pH of the blood. The bones have the largest store of alkaline elements (calcium and magnesium). Thus calcium is released from the bones into the blood stream. Later, the calcium absorbed from the bones may be excreted, and if the diet is predominantly acidic, an equal amount of calcium may not be returned to the bones. Consequently, over time, an acid diet can be a factor in osteoporosis.
There is a connection between constipation and a diet that is too acid. The digestive juices secreted by the small intestine are alkaline. After the food is digested, these alkaline elements in solution are reabsorbed from the stool along with the nutrients from the food. When the body has a dietary deficiency of alkaline minerals, the reabsorption of the alkaline digestive elements in the intestines is, by necessity, more complete, removing excess water and thereby hardening the stool. So constipation can be a symptom of a diet that is deficient in alkaline elements. That’s why magnesium salts, which are very alkaline, are often used to relieve constipation.
Some neutral or even alkaline foods may still have a short-term acidic effect. For example, all carbonated beverages contain the organic acid, carbonic acid H2CO3, which breaks down into water and carbon dioxide. However, during the short period of time the carbonic acid is in the blood stream, calcium may still be drawn out of the bones. Some carbonated beverages also contain phosphoric acid, which is a mortal enemy of bone tissue.
Cocoa is very high in oxalic acid, another enemy of bone tissue. Oxalic acid is also associated with kidney stones.
View pdf of Chart of Acid/Alkaline Values of Various Foods Listed by Type of Food
View pdf of Chart of Acid/Alkaline Values of Various Foods Listed by Degree
*From Robert Chuckrow, The Intelligent Dieter’s Guide, Rising Mist Publications, Briarcliff Manor, NY, 1997, p. 76.
©Copyright 1997 by Robert Chuckrow
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