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Labs/Methylmalonic Acid (MMA) Test
Clinical Test & Procedure Reference

Methylmalonic Acid (MMA) Test

This test measures the amount of methylmalonic acid (MMA) in your blood or urine.

This test measures the amount of methylmalonic acid (MMA) in your blood or urine. MMA is a substance made in small amounts when you digest protein. MMA is needed for metabolism, which is the process that your body uses to change food into energy. Vitamin B12 plays an important role in metabolism. Part of this role is breaking down MMA into substances that help with metabolism. If your body doesn't have enough vitamin B12, it will continue to make more MMA than is broken down. High MMA levels can be a sign of a vitamin B12 deficiency. Vitamin B12 deficiency can happen if you are not eating enough B12 in your diet or if your body has difficulty absorbing it. Your body cannot make vitamin B12 on its own, so you have to get it from the foods you eat. This vitamin is found in foods such as: Seafood such as fish, clams, and oysters Dairy products Chicken Eggs Meat Vitamin B12 is also found in some fortified foods, meaning the food has vitamins added to it. It's also available as a supplement. Vitamin B12 also helps to make red blood cells. A deficiency can lead to health issues, including anemia . This is a condition in which your blood has a lower-than-normal amount of red blood cells. Other names: MMA

Why is this test ordered? You may need this test if you have symptoms of a vitamin B12 deficiency. These may include: Fatigue Diarrhea Dizziness Shortness of breath Loss of appetite Tingling in hands and/or feet Mood changes Confusion Irritability Pale skin You might be at a higher risk for B12 deficiency if you: Are a strict vegetarian or vegan Have a digestive disease , such as celiac disease or Crohn's disease Are a person with an alcohol use disorder (AUD) Are older than 75 years Have Sjogren's syndrome , a disease that causes dry eyes and mouth Have had certain types of stomach or intestinal surgery If you have a new baby, they will probably be tested as part of a newborn screening.

Clinical Interpretation

If your results show higher-than-normal levels of MMA , it may mean you have a vitamin B12 deficiency. The test can't show how much of a deficiency. To help make a diagnosis, your provider may compare your results with other tests including a homocysteine blood test and/or vitamin B tests . Lower-than-normal levels of MMA are not common and are not considered a health problem. If your baby has moderate or high levels of MMA , it may mean that they have methylmalonic acidemia. If it's not treated, it can cause life-threatening complications. If your baby is diagnosed with this disorder, talk to your child's provider about treatment options. If you have questions about your results, talk to your provider. Your provider will consider your symptoms, medical history, and the results of other blood tests. Learn more about laboratory tests, reference ranges, and understanding results .

Clinical Protocol & Patient Advice

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    You may need to fast (not eat or drink) for several hours before your test. Your provider will let you know if there are any special instructions to follow.

Usage Guidance

  • Reference ranges vary by laboratory. Always discuss your specific results with a qualified healthcare professional.

Source: MedlinePlus, National Library of Medicine. View the original.