Dependence of bioavailability of folic acid and (6S)-5-methyltetrahydrofolate on baseline red blood cell folate concentrations in infants
Bibliographic record
Abstract
Background Folate bioavailability may depend on folate status of an individual and the form of folate presents in foods. Objective We studied whether changes of red blood cell (RBC)-folate concentrations following dietary intervention with folic acid or the calcium salt of (6S)-5-methyltetrahydrofolate (5-MTHF-Ca) depend on baseline RBC-folate and differ by the folate form provided. Methods We studied 167 infants randomized to infant formula with either 15.2 μg folic acid or 15.8 μg 5-MTHF-Ca per 100 kcal from <1 month of age (baseline visit) until age 16 weeks (visit 4). Generalised Additive Models (GAMs) were used to study whether the changes in RBC-folate concentrations between baseline visit and visit 4 (study outcome) depend on the intervention (folic acid or 5-MTHF-Ca), length of the intervention and a smooth effect of baseline RBC-folate concentrations for each intervention group. Results The GAM base model showed that the change of RBC-folate was higher in infants with lower baseline RBC-folate concentrations. This model explained 42 % of the deviance in the data. For the group that received folic acid, this effect was estimated to be linear (effective degrees of freedom = 1). In the group receiving 5-MTHF-Ca, the effect of baseline RBC-folate on the change of RBC-folate was non-linear. The smooth effect of baseline RBC-folate on the change of RBC-folate concentrations differed between the intervention groups (p = 0.002). In infants with higher baseline RBC-folate concentrations, the change of RBC-folate concentration is systematically higher in the 5-MTHF-Ca group than in the folic acid group. Conclusion The bioavailability of folic acid and 5-MTHF-Ca shows physiological decline when baseline RBC-folate is high. The reduction of the bioavailability is more pronounced after folic acid intake. The results may impact infant's intake recommendations from different folate forms. The molecular mechanisms behind these results deserve further investigations.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.006 | 0.029 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".