The natural health sector and alternative medical field is full of claims and statements about the importance of alkaline foods and the alkaline diet. Some of the claims made hold up under scrutiny and, well, some don’t. What is rarely considered is the major role that breathing has on the acid base balance in the body!
The body works tirelessly to maintain a stable pH in e.g. blood plasma, organ fluids and intra-cellular fluids. By weight, the average human adult male is approximately 69% water. That is 50 litres of fluid that are constantly chemically processed!
The two main ways in which the body neutralizes acids is via the breathing reflex and via the kidneys. A change in breathing is immediate and kicks in every time the acidity level goes up. This is every time you eat (most foods)! The acid is converted into CO2 which we breathe out. This process maintains a stable pH throughout. Should this not be enough, after a few hours the kidneys will start to dump bicarbonate to re-balance pH. You know when this happens because you start to pee more often! This process is very effective but can also leave us exhausted.
So, does eating acidic food make us acidic?
No, because the body compensates all the time to maintain a stable pH! If the pH of blood plasma even changes by more than 0.1 the body goes into a major crisis. If the pH drops below 7 we die. It is never possible to have an acidic body (speaking of fluids here except urine).
Does eating acidic food make us sick?
If you do it often enough – yes! This unfortunately is the case if you eat a standard western diet. Its over-reliance on nutrient-poor food will deplete the body of minerals and other goodies. This is because the body requires these to neutralize the acids. If it doesn’t get these from the food it will take them from the body’s stores such as the bones and skin. Better to help the body, I’d say!
What to take away from this?
Well, basically don’t worry about how alkaline a food is. Fretting over pseudo-scientific charts with alkalinity numbers of different foods is stressful. Some people thrive on an alkaline diet, some thrive on a Paleo Diet but obsession is never useful. What does seem to matter is to eat a nutrient rich diet that is well balanced with plenty of fibre. Not overeating and eating in a calm state is important, as is listening to what the body tells us it wants, too.
How does diet affect breathing?
Breathing is partially habit formed, so imagine you are eating a standard western diet and eat acidic foods often. This would mean that most of the time your breath rate is slightly elevated in order to re-balance pH. This does not affect CO2 levels initially but your body will learn to keep the higher breath rate and over time your CO2 levels may drop and your body pH may shift just slightly.
How does breathing affect diet?
Poor breathing means breathing more than you need. This affects pH levels constantly and minerals are needed to re-balance pH. There are no studies but it seems plausible and likely that poor breathing has a much greater effect on mineral depletion than an acidic diet.
As breathing returns to normal, cells become more oxygenated. This means less acid is produced in cellular respiration and hence, less minerals required to re-balance pH. Cells function better and require less energy. This may have the side effect of feeling less hungry – quite a nice bonus of breathing retraining!
What does science have to say?
There is a very nice review article here about the potential benefits of an alkaline diet as science understood it in 2012.