The natural health field is saturated with advice and products that are built around the premise of alkalizing your blood. The truth is that what you eat has little to no effect on the pH of your blood, which is tightly regulated by a complex system of buffers that are continuously at work to maintain a range of 7.35 to 7.45, which is slightly more alkaline than pure water. What you eat is a critical determinant of your health status, and the foods and beverages that you choose do tend to have acid or alkaline-forming effects on your overall system, but you cannot “alkalize your blood” through your food choices. Understanding this concept is essential to identifying and differentiating between hype and substance in the natural health arena.
If the pH of your blood falls below 7.35, the result is a condition called acidosis, a state that leads to central nervous system depression. Severe acidosis – where blood pH falls below 7.00 – can lead to a coma and even death.
If the pH of your blood rises above 7.45, the result is alkalosis. Severe alkalosis can also lead to death but through a different mechanism; alkalosis causes all of the nerves in your body to become hypersensitive and over-excitable, often resulting in muscle spasms, nervousness, and convulsions. It`s usually the convulsions that cause death in severe cases.
The bottom line is that if you`re out and about, your body is doing an adequate job of keeping your blood pH somewhere between 7.35 to 7.45, and the foods that you are eating are not causing any wild deviations of your blood pH.
So, what`s up with all the hype about the need to alkalize your body? And what`s to be made of the claim that being too acidic can cause osteoporosis, kidney stones, and a number of other undesirable health challenges?
As usual, the answers to such questions about human health can be found by understanding basic principles of human physiology. So, let`s take a look at the fundamentals of pH and how your body regulates the acid-alkaline balance of its fluids on a moment-to-moment basis.
pH is a measure of how acidic or alkaline a liquid is. With respect to your health, the liquids involved are your body fluids, which can be categorized into the following two main groups:
- Intracellular fluid, which is the fluid found in all of your cells – Intracellular fluid is often called cytosol and makes up about two-thirds of the total amount of fluid in your body.
- Extracellular fluid, which is the fluid found outside of your cells – Extracellular fluids are further classified as one of two types:
* Plasma, which is fluid that makes up your blood
* Interstitial fluid, which occupies all of the spaces that surround your tissues
Interstitial fluid includes the fluids found in your eyes, lymphatic system, joints, nervous system, and between the protective membranes that surround your cardiovascular, respiratory, and abdominal cavities.
Your blood (plasma) needs to maintain a pH of 7.35 to 7.45 for your cells to function properly. Why your cells require your blood to maintain a pH in this range to stay healthy is beyond the scope of this article, but the most important reason is that all of the proteins that work in your body have to maintain a specific geometric shape to function, and the three-dimensional shapes of the proteins in your body are affected by the tiniest changes in the pH of your body fluids.
The pH scale ranges from 0 to 14. A liquid that has a pH of 7 is considered to be neutral (pure water is generally considered to have a neutral pH). Fluids that have a pH below 7 – like lemon juice and coffee – are considered to be acidic. And fluids that have a pH above 7 – like human blood and milk of magnesia – are considered to be alkaline.
It`s important to note that on the pH scale, each number represents a tenfold difference from adjacent numbers; in other words, a liquid that has a pH of 6 is ten times more acidic than a liquid that has a pH of 7, and a liquid with a pH of 5 is one hundred times more acidic than pure water. Most carbonated soft drinks (pop) have a pH of about 3, making them about ten thousand times more acidic than pure water. Please remember this the next time you think about drinking a can of soda.
As your cells produce energy on a continual basis, a number of different acids are formed and released into your body fluids. These acids – generated by your everyday metabolic activities – are unavoidable; as long as your body has to generate energy to survive, it will produce a continuous supply of acids.
So, there are two main forces at work on a daily basis that can disrupt the pH of your body fluids. These forces are the acid or alkaline-forming effects of foods and liquids that you ingest, and the acids that you generate through regular metabolic activities. Fortunately, your body has three major mechanisms at work at all times to prevent these forces from shifting the pH of your blood outside of the 7.35 to 7.45 range.
These mechanisms are:
- 1. Buffer Systems
- * Carbonic Acid-Bicarbonate Buffer System
- * Protein Buffer System
- * Phosphate Buffer System
- 2. Exhalation of Carbon Dioxide
- 3. Elimination of Hydrogen Ions via Kidneys
It`s not in the scope of this article to discuss the mechanisms listed above in detail. For this article, the relevant point is that these systems are in place to prevent dietary, metabolic, and other factors from pushing the pH of your blood outside of the 7.35 to 7.45 range.
The primary purpose of this article is to offer information that explains why basic science dictates that you don`t need to take one or more nutritional supplements for the sole purpose of alkalizing your body. Your body is already designed to keep the pH of your body fluids in a tight, slightly alkaline range.
The ideal scenario is to make fresh vegetables and fruits the centerpieces of your diet, and to eat small amounts of any other nutrient-dense foods that your appetite calls for and that experience shows your body can tolerate.
– Lehninger Principles of Biochemistry, 2nd Edition
– Guyton Textbook of Medical Physiology
– Derrickson Principles of Anatomy and Physiology, 2nd Edition
The alkaline Myth & Hype – The Acid-Alkaline Truth Exposed