Are you related to blueberry bushes and oceanic coral reefs? Yes, we all are! We’re all very sensitive to the acid/base balance of our environment. Blueberry bushes must have an unusually acid soil to grow in, or they won’t thrive. Sea corals must have an alkaline oceanic environment, or they won’t survive. A contributing factor to coral reef stress today is the slightly increasing acidity of oceanic waters.
The Power of Hydrogen Ions (pH)
Acidity is determined by the concentration of hydrogen ions present in the fluid or medium involved. The more hydrogen ions there are, the more acid it is. Hydrogen ion concentration is expressed by the symbol pH, which can vary from 1 (extremely acid) to 14 (extremely alkaline). A pH of 7.0 is neutral.
Humans are very sensitive to their internal acid/base balance. Normal serum pH is very close to 7.4, on the slightly alkaline side of neutral. Our bodies are programmed to do everything possible to keep our serum pH between 7.3 and 7.5. Deviation outside this range carries a risk of coma or death, so the body fights fiercely to keep serum pH in its normal range.
However, other fluids in the body have different norms. Salivary pH tends to be slightly acid. Gastric juices are strongly acidic, so gastric contents have a pH of about 2.0, while bile and pancreatic juices are alkaline. A pH of 7.5 to 8.2 is normal in the small intestine. What this means is that any food or fluids we consume are put through acid and alkaline wringers in the process of digestion. It’s the pH of the products of digestion that really count in the end, for they’re what’s carried through the blood stream to cells and tissues throughout the body.
Acidity and Alkalinity of Various Foods
Most vegetables and fruits leave an alkaline residue in the body after digestion, while most meats, dairy products and processed foods leave an acid residue after digestion, which the body must neutralize. Since the body is basically a bit alkaline, it handles fruits and vegetables most easily.
Processing acid residues to keep serum pH in normal range is more complicated. The lungs and the kidneys are involved in complex buffering systems that help maintain normal pH. The lungs exhale excess carbon dioxide and the kidneys can create a more acid urine. Long-term acidosis may mobilize calcium from bones, resulting in weaker bones and a net loss of calcium in the urine. The more such neutralization is needed, the more cost there is to the body.
The message our bodies give us is that most vegetables and fruits are easier to digest and better for long-term health than other kinds of food. Statistically, the average American eats less than three servings of fruit and vegetables daily. Ideally, eating six to ten servings a day serves our bodies better. That doesn’t mean that we have to become vegan or vegetarian, but it does underline the concept that eating lots of fruits and vegetables is a good idea.
Here is a chart, Food & Chemical Effects on Acid/Alkaline Body Chemical Balance (TM), to help you understand which foods, beverages and spices best support your body’s efforts to maintain an ideal pH. Please note that the middle column in the chart (the white column) simply lists the food categories of the foods shown in the corresponding areas of the columns on either side. The foods listed in the columns to the right are progressively more acid, while the foods listed in the columns to the left are progressively more alkaline. There’s a lot to digest (pun intended) in this chart, so study it carefully if you wish to get maximum benefit from it.
Ed Dodge, MD, MPH
This post was published first in Dr. Ed Dodge’s Wellness Newsletter, Volume VI, No. 8 • August 23, 2014.