investigation

Last reviewed 01/2018

Vitamin status can be assessed in several ways:

• plasma concentration of:
• vitamin
• vitamin's metabolite
• urinary concentration of:
• vitamin
• vitamin's metabolite
• cellular concentration of vitamin e.g. erythrocyte folate levels
• in vitro activity of compound that requires vitamin for its activity e.g. trans-ketolase for thiamine

Practically, rather than determine the concentration or activity of a given vitamin, it is often easier to provide supplements and determine if there is a clinical response.