Did you know that the pH of the human body ranges between 7.35 and 7.45, which is slightly alkaline? But what happens when body acid levels rise? Dr Priyanka Rohatgi, chief nutritionist, Apollo Hospitals, says when body acid levels rise, it typically refers to an increase in the concentration of acid in the bloodstream or a decrease in blood pH, resulting in a condition called acidosis. Acidosis can occur due to various reasons, including metabolic and respiratory factors. The two common types of acidosis and their effects are:
Metabolic acidosis: This type of acidosis occurs when there is an excess production of acid or a decrease in elimination of acid from the body. Some causes of metabolic acidosis include:
Diabetic ketoacidosis: In uncontrolled diabetes, the body cannot effectively use glucose for energy, so it starts breaking down fat for energy, leading to the production of ketones. Ketones are acidic byproducts that can cause metabolic acidosis.
Kidney disease: The kidneys play a crucial role in maintaining acid-base balance. When they are unable to excrete sufficient acid or retain enough bicarbonate, metabolic acidosis can develop.
Lactic acidosis: This occurs when there is an accumulation of lactic acid in the body, often seen in conditions like infections, liver disease or certain medications.
Respiratory Acidosis: This type of acidosis occurs when there is an impaired exchange of carbon dioxide in the lungs, leading to an accumulation of CO2 in the bloodstream. Some causes of respiratory acidosis include:
Lung diseases: Conditions such as chronic obstructive pulmonary disease, asthma, pneumonia or respiratory muscle weakness can hinder the removal of CO2 from the body, resulting in this acidosis.
Impaired breathing: Anything that disrupts normal breathing, such as chest trauma, drug overdose, or central nervous system depression, can contribute to respiratory acidosis.
What are reliable indicators of acidosis?
Reliable indicators of acidosis can vary depending on the type of acidosis (metabolic or respiratory) and its severity. Here are some common indicators and tests used to diagnose acidosis:
Blood pH: A decrease in blood pH below the normal range of 7.35 to 7.45 is a reliable indicator of acidosis. A pH value lower than 7.35 suggests acidemia.
Blood gas analysis: This test measures the levels of oxygen, carbon dioxide and pH in the arterial blood. It provides valuable information about the acid-base balance and can help determine the presence and type of acidosis.
Bicarbonate (HCO3-) levels: Bicarbonate is an important buffer that helps regulate pH. In metabolic acidosis, the bicarbonate levels in the blood are usually decreased. Normal bicarbonate levels range from 22 to 28 milliequivalents per litre (mEq/L).
Carbon dioxide (CO2) levels: In respiratory acidosis, there is an accumulation of carbon dioxide in the bloodstream. This can be assessed by measuring the partial pressure of carbon dioxide (PaCO2) in arterial blood using a blood gas analysis. Elevated CO2 levels are indicative of respiratory acidosis.
Anion gap: The anion gap is calculated from the levels of sodium (Na+), chloride (Cl-), and bicarbonate (HCO3-) in the blood. It helps assess metabolic acidosis and determine the cause. An elevated anion gap indicates the presence of certain acidosis-causing substances in the blood.
Symptoms and clinical signs: Symptoms of acidosis may include rapid breathing (hyperventilation), confusion, fatigue, nausea, vomiting, and in severe cases, it can lead to organ dysfunction or coma. Clinical signs such as low blood pressure, increased heart rate and abnormal breathing patterns may also be present.
Why are we advised to prefer alkaline foods?
The concept of consuming alkaline foods is based on the belief that certain foods can influence the pH level of the body and promote a more alkaline (basic) environment. The theory suggests that maintaining an alkaline state in the body can have health benefits and help prevent various diseases. However, it is important to note that the human body has sophisticated mechanisms to regulate pH levels and keep them within a narrow range, regardless of the foods we consume. Here are a few reasons why consuming a balanced diet is generally advised:
Nutritional balance: Following a balanced diet that includes a variety of foods, including both acidic and alkaline foods, helps ensure you receive a wide range of essential nutrients, vitamins and minerals. Focusing solely on alkaline foods may lead to an imbalanced diet and nutrient deficiencies.
Healthful choices: Many alkaline-promoting foods are fruits, vegetables, whole grain and plant-based proteins, which are generally considered healthy food choices. These foods are often rich in fibre, antioxidants and other beneficial compounds that support overall health.
Acid-base balance: While the pH of the foods we consume can influence the pH of urine, it doesn’t significantly impact the pH of the blood or other tissues in the body. The body has natural buffering systems and regulatory mechanisms to maintain a stable blood pH, usually between 7.35 and 7.45. Deviations from this range can have serious health consequences.
Kidney function: Consuming excessive alkaline foods or supplements can potentially burden the kidneys and affect their normal function.
Should we avoid acidic foods totally in case of acidosis?
In cases of acidosis, it is not necessary to completely avoid all acidic foods. However, it is important to understand that the development of acidosis is usually due to underlying medical conditions or physiological imbalances, rather than solely caused by the consumption of acidic foods. While the pH of foods can vary, the body has effective mechanisms for maintaining acid-base balance.
