What is Methylmalonic Acid?
Methylmalonic acid is a compound produced during amino acid metabolism that increases with vitamin B12 deficiency. Vitamin B12 is an essential nutrient that can only be obtained from the diet. Deficiency can result in cognitive and mental problems, dizziness, numbness, and neurological damage. Vitamin B12 deficiency is relatively common. Up to 20% of the elderly population may have insufficient Vitamin B12. Pregnant women, vegetarians, vegans and people with poor absorption, intestinal diseases or those taking stomach acid pills are at increased risk of B12 deficiency.
The Methylmalonic acid (MMA) test, along with a homocysteine test, can help to uncover an early or mild vitamin B12 deficiency. They are often ordered together when a person’s vitamin B12 test result is in the lower half of the reference range, especially if they have symptoms or clinical indications of vitamin B12 deficiency.
Why test MMA?
Health check
Discover your risk factors for lifestyle diseases in time to do something about them.
Symptoms of B12 deficiency
There are many symptoms of vitamin B12 deficiency, including difficulty walking, mood swings, numbness in your hands or feet, difficulty in thinking clearly, fatigue, headaches, depression, anemia, infertility, insomnia, irritability, and anxiety.
Low serum B12
Your serum B12 measures in the lowest half of the reference range.
More information
Vitamin B12 deficiency can result in cognitive and mental problems, dizziness, numbness, and neurological damage. MMA increases in concentration when vitamin B12 is deficient and is a marker of vitamin B12 deficiency. Kidney disease can falsely elevate MMA.
Vitamin B12 deficiency is common. Up to 20% of the elderly population may have insufficient vitamin B12 levels. Pregnant women, vegetarians, vegans, people with poor absorption, intestinal diseases or those taking stomach acid pills are all at increased risk of B12 deficiency.
Although MMA is considered the current ‘gold standard’ of vitamin B12 testing, it is significantly more expensive than a serum vitamin B12 test. Hence your doctor will usually order a vitamin B12 test first, and only possibly order an MMA test if B12 is in the lower half of the reference range, and you have symptoms of deficiency or insufficiency.
Testing both vitamin B12 and MMA together gives a better picture of your B12 status.
What do the results mean?
MMA tests are interpreted considering other tests and the clinical picture. If MMA and homocysteine levels are normal, a B12 deficiency is unlikely to be the cause of any symptoms.
What causes low MMA levels?
Low MMA is the expected result and is not considered clinically significant.
What causes high MMA levels?
If your MMA and homocysteine levels are increased and your vitamin B12 level is mildly decreased, then an early or mild B12 deficiency may be present. There may be a lack of availability of B12 at the tissue level. If the homocysteine level is elevated and MMA is normal, a folate deficiency may be present. This is important because it is important to distinguish a B12 deficiency from a folate deficiency. Moderately to severely elevated levels of MMA may be seen in infants with the rare inherited disease methylmalonic acidemia.
Instructions
No advance preparation is required for this test.
On the day
Remember to take your ID with you when going to take a test.