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DigestiveDetected by blood test

Vitamin B12 deficiency

Low levels of vitamin B12, essential for nerve function and red blood cell production. Blood testing detects deficiency before it causes anemia, neurological symptoms, or cognitive decline.

Early detection matters

Our comprehensive check-up screens for vitamin b12 deficiency and hundreds of other conditions.

Related biomarkers we test

Homocysteine

Homocysteine is an amino acid your body makes when it processes protein from food. It normally doesn't build up, because your body recycles or breaks it down with the help of vitamin B12, folate and vitamin B6. When one of these runs short, homocysteine rises in the blood, often before the vitamin level itself looks clearly low. That makes it a useful check alongside B12 and folate: it shows whether your body actually has enough of them to work with. A raised value isn't only about vitamins, though. Reduced kidney function, an underactive thyroid, some medicines (such as metformin, methotrexate or certain epilepsy drugs), smoking, a lot of coffee, older age and inherited differences such as MTHFR variants can all raise it. Raised homocysteine is also linked to a higher risk of heart attack and stroke, but lowering it with B-vitamins has not been shown to prevent heart attacks. At Ahead it is measured together with B12 and folate, mainly to check whether your body has enough of these vitamins.

Mean corpuscular volume (MCV)

Mean Corpuscular Volume measures the average size of red blood cells. It helps diagnose different types of anemia - elevated in macrocytic anemia, decreased in microcytic anemia, and normal in normocytic anemia.

Vitamin B12

Vitamin B12 is a water-soluble vitamin essential for the production of red blood cells, the synthesis of DNA, and the healthy functioning of the nervous system. It also supports brain function and energy metabolism. The body cannot make B12 on its own and relies on dietary sources such as meat, fish, eggs, and dairy. Excess B12 is stored in the liver, so deficiency can take time to develop but may lead to serious health issues if not addressed.

Related conditions in Digestive