Please correct me if I'm wrong (not unlikely), but I had the impression that one's blood pH is regulated very closely, and much departure from 'bout 7.4 results in death. Compartments such as the bladder and mouth can depart from 7.4, prbly as part of whatever mechanism the body uses to keep blood pH stable, but neither are where your organs live.
SO, I don't get the point of alkalizing, unless something is wrong and body is barely able to keep blood pH stable.
Yes, the main buffer that keeps the blood pH very stable is the bicarbonate/carbonic acid buffer, and ingesting an external alkalizing agent like bicarbonate or citrate will barely alter the blood pH at all, because the buffer keeps pH within a very tight range. However, I believe the alkalizing agent will change the dynamics of operation of the buffer system.
This is analogous to a house with climate control: the climate control will always maintain the house at the same temperature, but the external weather changes the dynamics of operation of the climate control (hot weather turns on the air conditioning, whereas cold weather turns on the heating).
The health effects of alkalizing diets have not been studied much, but
this paper details some of them. From the ME/CFS perspective, the ability of alkalizing diets to raise intracellular magnesium might be of benefit.
In this instance, though, we are not so much interested in an alkalizing for health, but rather looking at the effect of ingesting bicarbonate on the higher than normal levels of lactic acid that ME/CFS patients produce in their muscle during physical exertion. The lactic acid from exercise puts a strain on the body's buffers, but supplementing with bicarbonate can help neutralize the acidity. This may then in turn reduce post-exertional malaise (PEM).
This article explains how bicarbonate helps reduce muscle lactic acid:
The body does have its own buffer system to prevent muscle pH from rising lactic acid and the muscle tissue becoming acidic. However, as a workout continues your body’s natural buffering system becomes unable to keep up with the acid levels. There are three main substances that buffer muscle cell tissue from rising pH levels and hydrogen ions: carnosine, phosphate, and bicarbonate (1). Interestingly, bicarbonate only accounts for less than ten percent of the body’s buffering potential. The body’s primary buffer in muscle tissue is carnosine with phosphate the secondary buffer (1).
Where sodium bicarbonate becomes more important to athletes in terms of buffering potential is in the blood. Exercise not only increases the acidity in your muscles but also acidifies your blood as well. When lactic acid levels rise in your blood, you get exercise-induced fatigue. The main buffer in the blood is sodium bicarbonate (2). This is how the idea came for athletes to ingest baking soda, otherwise known as sodium bicarbonate, to buffer their blood and muscles from acid. The concept was that by taking baking soda an athlete could train harder and longer because the added sodium bicarbonate would delay the rise in lactic acid levels.
The baking soda you eat or drink never makes it to your muscle tissue because it can’t make it through the muscle cell membranes, but it does make it into your blood stream (3). Because your body is always trying to reach a state of equilibrium, when your ingest the bicarbonate, it lowers your blood pH. This creates a gradient that brings the lactic acid out from the muscle tissue and into the blood stream, thereby lowering the pH of your muscle as well. Next, let’s examine how well this actually works on improving athletic endurance, performance, and time until exhaustion.
It's interesting to note that carnosine is the main buffer in the muscles. I wonder if boosting carnosine levels would also help neutralize lactic acid acidity in the muscles, and reduce PEM. The supplement
beta alanine converts to carnosine in the body (and is much cheaper to buy than carnosine).
Beta alanine is used as a lactic acid-reducing sports endurance supplement, so it may well have positive anti-PEM effects.
This is very helpful --