Thiamin (Vitamin B 1 ) - A scoping review for Nordic Nutrition Recommendations 2023.
Level 5 - mechanism / opinion, no new human data
Scoping review synthesizing expert consensus and physiological data without meta-analysis of randomized trials
PubMed 38084159 · doi:10.29219/fnr.v67.10290
What was done
A scoping review was conducted to evaluate the relationship between thiamin intake, biochemical markers, and clinical outcomes to inform dietary reference values for the Nordic Nutrition Recommendations 2023.
What was found
Clinical signs of deficiency appear at intakes below 0.5 mg/day, corresponding to 0.05 mg/MJ, which marks the estimated lower intake limit. Urinary thiamin excretion and enzyme activity normalized at intakes of 0.07-0.08 mg/MJ. Available evidence indicated higher requirements during pregnancy and lactation and suggested impaired thiamin utilization in older adults. Data were insufficient to establish a safe upper intake level.
Why it matters
This review establishes energy-adjusted reference benchmarks for thiamin intake and identifies specific life stages with increased physiological requirements.
Limits
The abstract reports that very few studies have evaluated intake-function relationships or baseline requirements in healthy populations. Total study count and sample sizes are not provided in the abstract, and inadequate data prevented the definition of an upper safety limit.
Cited by
- supports Consuming refined sugar and refined starches depletes B vitamins by increasing metabolic demand.