HOW ARE LEVELS OF VITAMIN B5 AND FUNCTIONALLY-RELATED B VITAMINS MEASURED TO ASSESS THEIR NUTRITIONAL STATUS, WITH COMMENTARY ON ASSESSMENT OF THEIR METABOLIC ROLES, PARTICULARLY IN THE HEALTHY BRAIN AND IN AGE-RELATED DEMENTIA?

Abstract

The group of B-vitamins comprises eight members all of which are water-soluble. Together they are essential for many normal metabolic processes of the cell including DNA synthesis. B-vitamins have been linked to processes of energy generation required by all tissues; therefore, a reduction of B-vitamins may lead to generalised defects in metabolism and improper cellular development and function. Thus, cognitive decline and age-related dementia might manifest from deterioration in brain-cell metabolism caused by insufficient intake of B-vitamins since they are involved in effective cell function and activity. This research had investigated manuscripts that have been published online, by their identification from the MEDLINE library accessed through the PubMed search engine. Thousands of potentially-relevant manuscripts were identified by this approach, then filtered by relevant further key words and PubMed filter tools. Final selection of manuscripts was based on the relevance of their titles and abstracts to the topics of B-vitamins and neurodegeneration. This research found that reduced levels of B-vitamins have a substantive connection to known vitamin-deficiency syndromes but also to idiopathic age-related neurodegenerative diseases such as Alzheimer’s disease and Huntington’s disease. In addition, B-vitamin replacement may ameliorate complications in some of these diseases. Furthermore, food fortification with B-vitamins has helped to reduce the impacts of their deficiency states in many countries. For example, treatment of pregnant women with folic acid has significantly lowered the prevalence of neural tube defects in the developing foetus. This research also found that the current biochemical assessments of B-vitamin status are generally of greater significance when levels of their metabolites are investigated rather those of the vitamins themselves. Finally, some of the B-vitamins function in a co-dependent pattern where one needs another to function properly. Dietary intakes of B-vitamins derived from foods are adequate in most developed countries where diets are sufficient, whereas populations in many less-developed countries continue to manifest vitamin insufficiency and consequent deficiency states. However, even in developed countries, deficient intakes caused by gastrointestinal tract diseases leading to malabsorption, and inadequate intakes mediated by advanced age, alcohol abuse or both, can cause deficiency. Finally, inadequate biochemical analysis of B-vitamins can be avoided by the measurement of their metabolites.