An acid is a substance with a pH of less than 7, where the closest the pH falls to a 0 value, the more acidic the substance. Alkaline substances have a pH of greater than 7. The closest the pH falls to 14, the more alkaline the substance. Substances with a pH of 7 are considered to be neutral.
When acid or alkaline substances are ingested they create a reaction or chemical process within the body. The ideal pH for these chemical processes to occur varies by location in the body and by process, but generally bodily functions occur best at a pH that is slightly alkaline and ranges from a pH of 7.39 to pH of 7.42 (Vasey, 2006).
No Two People Are the Same
Foods can be classified as acidifying, slightly acidifying, and alkalizing (Vasey, 2006). People metabolize foods in different manners. Two people could eat the exact same foods, and these could generate different results in the body. In other words, two people could eat an apple, and in one it could be acid-forming, and in the other it could be alkaline-forming. This could be due to different metabolisms, and different capabilities of digesting and utilizing foods and components. No two people are the same.
Different foods cause different reactions within the body, and the pH from these reactions determines how they are classified (Petersen, 2015). When the foods are broken down, the resulting metabolites create an acid condition or an alkaline condition in the body, but these reactions do not necessarily match the food’s properties. Even though some foods are classified as acidic or alkaline, the effect they have in the body is different. For instance, vinegar on its own is considered an acid, but it has a slightly acidifying effect in the body. Sugar on its own is alkaline, but it has an acidifying effect in the body (Vasey, 2006).
Acidifying versus Alkalizing Foods
Generally, acidifying foods include meats, poultry, cold cuts, fish, seafood, eggs, cheeses, animal fats, vegetable oils, whole and refined grains, breads, pasta, cereal, white sugar, legumes, sweets, oleaginous foods (most nuts and seeds, such as walnuts, hazelnuts, peanuts, and pumpkin seeds), sodas, coffee, tea, alcohol, cocoa, and condiments, such as mayonnaise, mustard, and ketchup (Petersen, 2015; Vasey, 2006).
Slightly acidifying foods include whey, yoghurt, curds, cottage cheese, unripe fruits, acidic fruits (berries and citrus), sweet fruits (melons and watermelons), acidic vegetables (tomatoes and eggplants), fermented vegetables, fruit juices, honey, and vinegar (Petersen, 2015; Vasey, 2006).
Alkalizing foods include potatoes, green and colored vegetables, corn, milk, bananas, almonds, Brazil nuts, chestnuts, dried fruits, black olives, almond milk, alkaline waters, avocado, and natural sugar (Petersen, 2015; Vasey, 2006).
Acidifying conditions occur in the body when too many acid-forming foods and not enough alkaline-forming foods are consumed.
It Isn’t Just About Food
Acid conditions also occur when a person is undergoing a lot of stress or tension or when there is either lack of exercise or extreme exercise that causes acid build-up in the body (Vasey, 2006). The body compensates for an overly acid condition through the lungs by breathing out carbon dioxide, and through the kidneys via urine. However, the body only has a limited capacity of eliminating excess acids in this way, and when too much acid accumulates, it leads to symptoms of illness (Vasey, 2006).
Acid accumulation in the body can lead to disruption of enzyme activity; irritation of other tissues and organs by the acid, which then makes these tissues vulnerable to infection; and loss of minerals that are released by the body, due to their alkaline nature, to neutralize the acid (Vasey, 2006). Common symptoms include skin irritation, eczema, hives, itching, painful urination, urethritis, cystitis, arthritis, nerve pain, intestinal problems and discomfort, osteoporosis, rheumatism, sciatica, toothache, cavities, hair loss, weak nails, fatigue, depression, cold sensitivity, low blood pressure, and respiratory tract infections, among others (Vasey, 2006).
How To Measure the Level of Acidity in the Body
There are several methods to identify the level of acidification in the body. The Acid-Alkaline Diet for Optimum Health by Christopher Vasey details these methods, and the information below is a summary of what is written in the book.
Testing pH in urine
The best way to measure the level of acidity in the body is to the test the pH of urine. Taking a litmus paper, placing urine on it, and determining the shade of color the litmus paper turns into is the easiest way to measure urine’s pH. Normal urine pH should vary between a pH of 7 to 7.5. To get an accurate reading of the level of acidity in the body, the urine used in the test should come from the second urination in the morning. It is important not to test the first urination because it will likely be more acidic from acids accumulating in the body overnight. The second testing should be the urination before lunch, and the third testing should be the urination before dinner. The pH values should be recorded, and include observations of different occurrences that happened in the day that could affect the pH value, such as stressful situations or meals in restaurants. Recurring low pH levels that are below the average of pH 7 to 7.5 would indicate an acidic condition in the body.
The other method of detecting acidification is doing a food analysis. This involves keeping a food journal over a period of time (2-4 weeks) that records the exact foods and beverages consumed. If acidic foods predominate, that would be an indication of a possible acidic condition in the body.
Testing Ability to Metabolize Acids
The test would look at the body's reaction to certain foods. The foods most important to test are slightly acidifying foods or weak-acid foods, because typically the body most poorly metabolizes them. These include whey, yoghurts, unripe fruits, fermented vegetables, fruit juices, honey, and vinegar. Increasing consumption of these foods for 1 or 2 days is enough to determine a reaction. A poor reaction would include increased fatigue, intensification of joint pain, increased blotches or irritation of the skin, nervousness, burning during urination, itching, or other similar symptoms. Symptoms could appear very quickly, if they are sensitive, and see a worsening in conditions within 30 minutes to an hour after consuming the meal. But, for others it could take longer. Sometimes, it is not necessary to conduct the test, particularly if there has been a poor reaction to consuming these foods in the past. If they have experienced some of the symptoms listed above, it is likely they have an inability to metabolize acids.
Although looking at the urine's pH, the types of food consumed, and testing how slightly-acidifying foods are metabolized can indicate the acidification in the body, the best way of analyzing the level of acidity in the body is by using multiple methods. This would provide a more accurate measure.
How to Correct Acidity
Specific diets need to be tailored to a person’s distinctive condition. Because people are unique in their interaction with food, it is important to customize the way acidity is corrected to the individual. Generally, acidity is corrected by eating a diet that is high in alkaline-forming foods. To help tip the balance and correct the acidic condition, for a period of one to two weeks (but no longer), only alkaline vegetables and plant-based food should be consumed (Vasey, 2006). Afterwards, it is important that in any one meal, there aren’t only acidifying foods (such as meat and rice), and that alkaline food is included in every meal (such as vegetables, corn, or potatoes). Also, the amount of alkalizing food should be greater than acidifying foods in every meal. Ideally the daily diet should contain 80% alkaline-forming and 20% acid-forming substances (Petersen, 2015). Acidic foods should only be introduced when the body is ready (Vasey, 2006).
Petersen, D. (2015). Acid-Alkaline Balance. In NUT 509 Graduate Topics in Holistic Nutrition. Portland, OR: American College of Healthcare Sciences.
Vasey, C. (2006). The Acid-Alkaline Diet for Optimum Health. Rochester, VT: Healing Arts Press.