Acid and Alkaline Elements
When each nutrient from food is assimilated it has an acid or alkaline effect on the blood and, consequently, on bodily tissues. The main elements that have acid and alkaline effects are summarized in the table below:
|Acid Elements||Alkaline Elements|
Table. The main acid and alkaline elements.
There is an erroneous idea that alkaline foods are good and acid foods are bad and should be avoided. This idea is wrong because we need both alkaline and acid elements. For example, phosphorus is needed for bones, nitrogen is in proteins, and chlorine is required for producing hydrochloric acid for digesting food. The goal is to attain a balance, four-to-one alkaline-to-acid ratio, corresponding to an ideal balance of nutrients for optimal health. Categorizing foods as acid or alkaline helps us in attaining that balance.
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.
Acid and Alkaline Foods
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).
Internal Acidity vs. Litmus Acidity
It is important to realize that the acidity or alkalinity in this context is not related to that of the food itself as measured with, say, litmus paper but its effect on the tissues after assimilation. 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) contained in citrus fruits is ultimately metabolized into water (H2O) and carbon dioxide (CO2):
2C6H8O7 + 9O2 ==> 8H2O + 12CO2.**
Water, of course, is neutral. Though acidic when in solution, carbon dioxide is readily eliminated via the lungs. Thus, when calculating the acidity or alkalinity of oranges, grapefruits, lemons and other fruits, citric acid is not counted. These fruits are considered to be alkaline because they are relatively high in the alkaline minerals listed in the following acid-alkaline tables and low in the acid elements listed therein.
Similarly, all compounds containing only carbon, hydrogen, and oxygen are metabolized into water and carbon dioxide and, therefore, are calculated as having a neutral acid-alkaline effect.
Tartaric acid (C4H6O6) in grapes, malic acid C4H6O5) in apples, and lactic acid (C3H6O3) in milk are correspondingly metabolized:
2C4H6O6 + 5O2 ==> 6H2O + 8CO2,
C4H6O5 + 3O2 ==> 3H2O + 4CO2,
C3H6O3 + 3O2 ==> 3H2O + 3CO2.
Again, the three organic acids above and others such as and acetic (C2H4O2) and carbonic (H2CO3) are disregarded when the acidity of a food is calculated.
Charts of Acid and Alkaline Foods in pdf Format
Listed by Type of Food
Listed by Degree
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 spontaneously breaks down into water and carbon dioxide:
H2CO3 ==> H2O + CO2.
However, during the short period of time the carbonic acid is in the bloodstream, calcium may still be drawn out of the bones and not all of it later replaced. Also, it is possible that magnesium may be released, contributing to nocturnal muscle cramps when carbonated beverages are consumed before bedtime (see article on leg cramps).
Some carbonated beverages also contain phosphoric acid, which is a mortal enemy of bone tissue.
All forms of sugar (fructose, lactose, dextrose, maltose, etc.) are converted to glucose (C6H12O6) when digested. As with other compounds containing only carbon, hydrogen, and oxygen, glucose is metabolized into water and carbon dioxide:
C6H12O6 + 6O2 ==> 6H2O + 6CO2.
Evidently, the claim that sugar is extremely acid is false; instead, sugar would be calculated as neutral. Refined white cane sugar is devoid of nutrients other than sucrose (sucrose is a combination of fructose and glucose), but raw (unrefined) sugar, which retains the nutrients of sugar cane, is quite alkaline and is available in supermarkets.
The sodium in salt is alkaline, and the chlorine is acid. Salt, however, is not neutral but slightly acid.
White Flour. A large problem is the consumption of highly acidic refined white flour, made from whole wheat all of whose valuable alkaline elements have been artificially removed. White flour abounds in breads, pasta, cakes, cookies, crackers, and many prepared foods. Eating such an artificially unbalanced food as white flour in the amounts commonly consumed makes it essentially impossible to obtain an optimal balance of nutrients.
Acid-Alkaline Balance and Bone Density
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 bloodstream. 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 bloodstream. 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.
Acid-Alkaline Balance and Constiption
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, thereby removing excess water and hardening the stool. So constipation can be a symptom of a diet that is deficient in alkaline elements. That idea is consistent with the fact that magnesium salts, which are very alkaline, are often used to relieve constipation.
*From Robert Chuckrow, The Intelligent Dieter’s Guide, Rising Mist Publications, Briarcliff Manor, NY, 1997, p. 76.
**This equation states that two molecules of citric acid combine with nine molecules of oxygen to form eight molecules of oxygen and twelve molecules of carbon dioxide. This equation is said to be balanced because the number of carbon molecules, those of hydrogen, and those of oxygen on one side of the equation equals that of those on the other side.
©Copyright 1997 by Robert Chuckrow
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