Your body maintains very tight control over the pH, or level of acidity, in your body. The proper pH is necessary for the biochemical reactions responsible for life to occur efficiently. Nutrients, vitamins and minerals from foods are themselves acidic or alkaline, and must be neutralized by your body. Your body can excrete acids in the urine as one way of neutralizing them. Meat, dairy and grains increase the amount of acids produced in your body. However, too many acids in the body can cause health problems. Eat alkaline foods, such as fruits and vegetables, to neutralize excess acids.
According to Dr. John Berardi, professional nutritionist and creator of the Precision Nutrition system, the most accurate method of measuring whether a particular food is acidic or alkaline is the measure the effect of the food on urine pH. Most modern diets are highly acidic, as grains, dairy and meats are acid-forming foods. When acid-producing foods are consumed, your body can either neutralize or excrete them, decreasing the pH of the urine. High consumption of acidic foods, without alkaline foods, can cause your body to draw calcium from your bones and protein from your muscles to neutralize the acids, as only a limited amount can be excreted in the urine.
Acidosis is a condition where the levels of acid in your body overwhelm your body's buffering systems, causing your blood to acidify. Diet alone is highly unlikely to result in acidosis severe enough to be detected by your doctor. Acidosis can cause rapid breathing, confusion and lethargy. Metabolic acidosis can be caused by complications of diabetes, kidney disease, dehydration and from some medications.
Meats, beans, legumes, grains, nuts, milk and cheeses cause your body to acidify as you metabolize them. A few fruits, such as cranberries and blueberries, are slightly acid-forming. Simple sugars are neutral, and contribute little to acid-base balance. As acid-forming food constitute a substantial and necessary part of your diet, it is impossible to avoid them. The acid-forming effects of these foods can be neutralized by also consuming acid-neutralizing foods.
Most fruits are acid-neutralizing, due in part to the high amounts of alkaline minerals, including potassium, calcium and magnesium. Like fruits, most vegetables are alkaline due to their high concentration of alkaline minerals. Berardi recommends consuming several servings of fruits and vegetables with each meal, especially those high in acid-forming foods.