Systematic Review of Observational Studies with Dose-Response Meta-Analysis between Folate Intake and Status Biomarkers in Adults and the Elderly

• Published in: Annals of nutrition and metabolism Vol. 73; no. 1; p. 30
• Main Authors: Novaković, Romana, Geelen, Anouk, Ristić-Medić, Danijela, Nikolić, Marina, Souverein, Olga W, McNulty, Helene, Duffy, Maresa, Hoey, Leane, Dullemeijer, Carla, Renkema, Jacoba M S, Gurinović, Mirjana, Glibetić, Marija, de Groot, Lisette C P G M, Van't Veer, Pieter
• Format: Journal Article
• Language: English
• Published: Switzerland 01.01.2018
• Subjects: Dose-response; Adults-elderly; Intake-status; Folate
• ISSN: 1421-9697
• DOI: 10.1159/000490003

Dietary reference values for folate intake vary widely across Europe. MEDLINE and Embase through November 2016 were searched for data on the association between folate intake and biomarkers (serum/plasma folate, red blood cell [RBC] folate, plasma homocysteine) from observational studies in healthy adults and elderly. The regression coefficient of biomarkers on intake (β) was extracted from each study, and the overall and stratified pooled β and SE (β) were obtained by random effects meta-analysis on a double log scale. These dose-response estimates may be used to derive folate intake reference values. For every doubling in folate intake, the changes in serum/plasma folate, RBC folate and plasma homocysteine were +22, +21, and -16% respectively. The overall pooled regression coefficients were β = 0.29 (95% CI 0.21-0.37) for serum/plasma folate (26 estimates from 17 studies), β = 0.28 (95% CI 0.21-0.36) for RBC (13 estimates from 11 studies), and β = -0.21 (95% CI -0.31 to -0.11) for plasma homocysteine (10 estimates from 6 studies). These estimates along with those from randomized controlled trials can be used for underpinning dietary recommendations for folate in adults and elderly.