Biomaterial Database

Diurnal variation of serum iron, iron-binding capacity, transferrin saturation, and ferritin levels. 2002

Jane C Dale, and Mary F Burritt, and Alan R Zinsmeister

Division of Clinical Biochemistry and Immunology, Mayo Clinic, Rochester, MN 55905, USA.

Serum iron levels vary throughout the day. Morning levels are generally assumed to be higher than afternoon or evening levels. We studied whether our practice of restricting serum iron collections to the morning was necessary. Serum iron, iron-binding capacity, transferrin saturation, and ferritin levels were determined on blood specimens obtained from 20 healthy adult volunteers at 8 AM, noon, and 4 PM (day 1) and 8 AM (day 2). Although statistically significant differences among mean values for the collection times were observed for iron, iron-binding capacity, and (log) ferritin, no consistent diurnal variation was seen. Morning iron levels were higher than afternoon levels for only half of the subjects. Between-day variation for all 4 analytes was similar to within-day variation. We conclude that the practice of restricting iron specimen collections to a specific time of day does not improve the reliability of the test result.

UI	MeSH Term	Description	Entries
D007501	Iron	A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.	Iron-56,Iron 56
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D001800	Blood Specimen Collection	The taking of a blood sample to determine its character as a whole, to identify levels of its component cells, chemicals, gases, or other constituents, to perform pathological examination, etc.	Blood Specimen Collections,Collection, Blood Specimen,Collections, Blood Specimen,Specimen Collection, Blood,Specimen Collections, Blood
D002940	Circadian Rhythm	The regular recurrence, in cycles of about 24 hours, of biological processes or activities, such as sensitivity to drugs or environmental and physiological stimuli.	Diurnal Rhythm,Nyctohemeral Rhythm,Twenty-Four Hour Rhythm,Nycthemeral Rhythm,Circadian Rhythms,Diurnal Rhythms,Nycthemeral Rhythms,Nyctohemeral Rhythms,Rhythm, Circadian,Rhythm, Diurnal,Rhythm, Nycthemeral,Rhythm, Nyctohemeral,Rhythm, Twenty-Four Hour,Rhythms, Circadian,Rhythms, Diurnal,Rhythms, Nycthemeral,Rhythms, Nyctohemeral,Rhythms, Twenty-Four Hour,Twenty Four Hour Rhythm,Twenty-Four Hour Rhythms
D005260	Female		Females
D005293	Ferritins	Iron-containing proteins that are widely distributed in animals, plants, and microorganisms. Their major function is to store IRON in a nontoxic bioavailable form. Each ferritin molecule consists of ferric iron in a hollow protein shell (APOFERRITINS) made of 24 subunits of various sequences depending on the species and tissue types.	Basic Isoferritin,Ferritin,Isoferritin,Isoferritin, Basic
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults