pH means “hydrogen potential”, a logarithmic scale that measures the degree of acidity, neutrality or alkalinity of a given solution.
The scale has values between 0 and 14, where 7 is considered the neutral value.
Values between 0 and 7 represent acidic substances; while values between 7 and 14 are found in alkaline substances.
The pH of the body
What is the typical mistake?
The formula to calculate a pH is given by pH=-log10[H+], which has been made for solutions at 25ºC.
However, our body is close to 37ºC, which means we need to correct the coefficient on the initial formula.
It is important to understand that the pH value normally attributed to blood (7.3-7.4) is not correct. Our blood is actually slightly more acidic, just below 7.
The pH of the body
How does the body become acid?
Even if you have not studied chemistry since school, the role of pH in the human body is relatively simple.
There are two key facts:
1 – A substance is considered acidic when it releases hydrogen ions (H+) in an aqueous medium.
2 – The pH is determined by the concentration of H+.
We are constantly producing acids, which releases H+ into our “internal environment”. By increasing the concentration of H+ in the medium and, in turn, we are acidifying the body – this is how diseases start to develop.
This is how we are made: our survival metabolisms produce acids (during feeding, physical exercise, stress…).
We need to rebalance and “clean” these H+ ions which are harmful to our health.
The myth of alkaline water?
Everything started in the 1930s in Japan, where they soon began to study the role of water in health – and perhaps that’s why it’s one of the populations with the highest average life expectancy.
When producing water with negative ORP (see here), the pH increased considerably (they lacked our know-how!).) … and when the time came to draw the conclusions from the studies, they wrongly attributed the health benefits to the fact that it was alkaline, and not to the fact that it had a negative ORP.
Alkaline water is not only unhealthy, but also the negative alkaline water sold in bottles on the market is not even ORP-negative.
The ideal pH
What is the ideal pH of water?
Different parts of the bodywork at different pH levels: For example, the stomach needs to be extremely acidic (pH 1-2) to make digestion effective.
Bad digestions are one of the first consequences of drinking alkaline water, as it will come into direct contact with this medium and counteract it.
The scientific literature1 tells us, through a randomized controlled human study 2, that an “alkaline diet” only has an effect on the pH of urine, and not on the systemic pH – the one that is really important to control.
This idea is advocated by the American Institute of Cancer Research and the Canadian Cancer Society.
The ideal pH of water is neutral (7) or slightly acidic – the true pH of blood, which we mentioned above.
1 Fenton TR, Huang T, Systematic review of the association between dietary acid load, alkaline water and cancer, BMJ Open (2016).
2 Wright ME, Michaud DS, Pietinen P, et al. Estimated urine pH and bladder cancer risk in a cohort of male smokers (Finland), Cancer Causes Control (2005).