- Metabolic acidosis is a condition where the blood is overly acidic with a pH of 7.3 or below.
- Metabolic acidosis can come on quickly, over 24 hours, and be deadly if not treated immediately.
- Metabolic acidosis can also be a chronic condition that lasts months.
- This article was medically reviewed by Pietro A. Canetta, MD, board-certified in nephrology and internal medicine and Assistant Professor of Medicine at Columbia University Irving Medical Centre.
- Visit Insider’s homepage for more stories.
Metabolic acidosis is a type of acidosis, which occurs when the blood is more acidic than what’s considered healthy. A normal blood pH is between 7.37 and 7.43 on a scale of 0 to 14 – 0 being the most acidic.
There are two main organs that control your blood pH, the kidneys and lungs. Metabolic acidosis most often happens when there’s an issue with the kidneys where they either cannot purge excess acid from the blood or diffuse it with bicarbonate, a base. It can also happen if the body loses base from the intestines, as in severe diarrhoea.
There are many types of metabolic acidosis that can prove deadly within 72 hours or can last months depending on the circumstances. Here’s what you need to know about the different causes, symptoms, and treatments of metabolic acidosis.
What causes acute metabolic acidosis
Metabolic acidosis can either develop over short, bursts within hours – called acute metabolic acidosis – or can last for months – called chronic metabolic acidosis.
The most common form of acute metabolic acidosis is caused by severe diarrhoea. In this case, a significant amount of bicarbonate, which is a base that keeps the body’s pH in check, is lost.
There’s also acute onset of metabolic acidosis from poisoning due to the ingestion of antifreeze or large amounts of aspirin (acetylsalicylic acid). Symptoms include nausea, vomiting, seizures, hypotension, and congestive heart failure in the first 24 hours. The condition can be fatal if not treated immediately.
Another example of metabolic acidosis happens when your body has too many ketone acids in the blood, making it more acidic. This condition is known as ketoacidosis. One cause is diabetic ketoacidsosis, where low insulin levels or reduced sensitivity to insulin triggers the body to burn fat for energy (instead of glucose), which produces ketones.
Diabetic ketoacidosis is most common in people with type 1 diabetes – especially if they have missed an insulin dose – but type 2 diabetics can also be affected. It can also develop in diabetics experiencing certain physical stressors, often an infection like a UTI, but also things like substance abuse. Symptoms include stomach pain, nausea, vomiting and ultimately death if insulin levels aren’t restored.
Another form of ketoacidosis is alcoholic ketoacidosis, which often occurs in chronic alcoholics. It can develop when someone drinks too much alcohol and doesn’t eat any food for many hours. This sends the body into starvation mode, which kickstarts ketone production and can lead to abdominal pain, nausea, and vomiting.
What causes chronic metabolic acidosis
More commonly, metabolic acidosis presents as a chronic disorder. This occurs in people with chronic kidney disease (CKD) or renal failure because their bodies can’t regulate the acid load in the blood.
“The acid build-up over the long-term can cause damage to tissues, it can leak out calcium from your bones, there is a lot of long-term damage that it can cause,” said Anjay Rastogi, MD professor and clinical chief of Nephrology at UCLA Health.
Rastogi cautions that this form of metabolic acidosis is especially dangerous because it is usually asymptomatic. Similar to hypertension or osteoporosis, chronic metabolic acidosis is silent, but can cause loss of mass to bones and speeds up the rate at which kidney damage occurs.
How to treat acute and chronic metabolic acidosis
- Oral Rehydration Solution: This solution contains a base, usually bicarbonate, that is often used to treat dehydration. In the case of metabolic acidosis, it can help treat cases that are caused by diarrhoea.
- Renal replacement therapy. This serious procedure uses dialysis and other blood filtering procedures to do the work of the kidneys. It is recommended for patients with kidney failure with both acute and chronic, severe metabolic acidosis.
- Plant-based diet. Chronic patients who also are being treated for hypertensive kidney disease benefit from a balanced diet rich in fruits, vegetables and low-fat proteins. Eating less red meat can also help regulate acid levels for people with chronic metabolic acidosis because when we digest animal proteins it generates acid, in the form of amino acids, in the bloodstream.
Rastogi says that people with chronic metabolic acidosis should look at how they eat and use that as a starting place to control the acid load in their body. High-protein diets have a high acid load; whereas, fruits, vegetables, and diets rich in salads have an alkalizing effect on blood pH.
“Drugs should not be a replacement for lifestyle changes. Medications can only do so much,” he says. “Stick to whole vegetables and leafy greens. The normal, healthy, balanced diet.”