Diagnostics Tests

Vitamins and Co-Factors


Vitamins are organic compounds that are needed in small quantities to sustain life. Most of them come from food intake or supplementation as the human body either does not produce enough or does not produce any at all. They are also essential to support metabolism and bodily functions, so any vitamin deficiency can lead to certain medical conditions.

There are 2 types of Vitamins:

    1. Fat Soluble Vitamins are stored in the fatty tissues of the body and the liver. Vitamins A, D, E, and K are all fat-soluble. They are easier to store than water-soluble vitamins and can stay in the body for days, and sometimes months. They are absorbed through the intestinal tract with the help of fats or lipids.
    2. Water Soluble Vitamins do not stay in the body for long. The body cannot store them and are soon excreted through the urine. Because of this, water-soluble vitamins need to be replaced more often than fat-soluble ones. Vitamin C and all B vitamins are water soluble.

Different specimen types are used to properly assess vitamin deficiency and reduce environmental variables that influence results. For example, serum retinol is the ideal biomarker and gold standard for vitamin A testing as they are stored in the liver and not excreted during urination. Serum retinol concentrations serve as a good indicator when liver reserves are dangerously low. Another example is the use of LC-MS/MS analysis of thiamine diphosphate in whole blood as it is the most sensitive, specific, and precise method for determining the nutritional status of thiamine, and it is also a reliable indicator of total body stores. This assay specifically targets and quantitates thiamine diphosphate (the active form of vitamin B1) as an indicator of vitamin’s status. Serum or plasma thiamine testing suffers from poor sensitivity and specificity, and only less than 10% of blood thiamine is contained in plasma.

MetaMetrics offers a comprehensive range of diagnostic tests to measure vitamin deficiency. View our test list for more information.