The pH scale measures the acidity or alkalinity of a substance. Substances with a pH level lower than 7 are called acidic, while substances with a higher pH are called alkaline. The pH of foods doesn’t always correspond to their acid-forming or alkaline-forming properties in the body.
How PH Affects The Body
The human body is almost 70 percent water. Water is considered neutral on the pH scale, at about 7. Blood is slightly alkaline, normally between 7.35 and 7.45. If the pH falls below that, a condition called acidosis occurs. If the pH is higher, the condition is called alkalosis. Both conditions can be fatal.
Acidity In The Body
Acids are formed in the body when metabolism occurs, as well as when you eat acid-forming foods. Highly processed foods, sugar, caffeine and most proteins are considered acid-forming and put strain on the body’s systems to maintain proper pH balance. A food doesn’t have to have a low pH to be considered acid-forming in the body.
Alkalinity In The Body
Several systems in the body ensure that the pH balance of the blood and other bodily fluids are maintained at a slightly alkaline level. The respiratory system and the excretory system both help eliminate acids in the body as does the ingestion of alkaline-forming foods such as leafy green vegetables. Some highly acidic foods, such as lemons, are alkaline-forming in the body.
Acidic Foods
Foods with low pH are not necessarily acid-forming in the body. Tomatoes are acidic but alkaline-forming in the body. It depends on how the food affects the pH of the urine. Also, highly acidic foods (those with low pH) require less heating than low-acid foods when canning. Examples of low pH foods are most jams, jellies and fruit.
Alkaline Foods
Most vegetables, meat and poultry have high pH levels and are considered to be alkaline, even though many of them are acid-producing in the body. These foods have to be canned with higher temperatures to prevent botulism.