L'acide folique aide à éliminer l'arsenic. Toujours utile car l'arsenic, il y a en plein dans des aliments comme le riz
Folic Acid and Creatine as Therapeutic Approaches to Lower Blood Arsenic: A Randomized Controlled Trial.
Peters BA Environ Health Perspect. 2015 May 15.
The WHO estimates that >140 million people worldwide are exposed to arsenic (As)-contaminated drinking water. Arsenic undergoes biologic methylation which facilitates renal As elimination. In folate deficient individuals, this process is augmented by folic acid (FA) supplementation thereby lowering blood As (bAs). Creatinine concentrations in urine are a robust predictor of As methylation patterns. While the reasons for this are unclear, creatine synthesis is a major consumer of methyl donors and its synthesis is downregulated by dietary/supplemental creatine.
OBJECTIVES:
To determine whether 400 or 800 µg FA and/or creatine supplementation lowers bAs in an As-exposed Bangladeshi population.
METHODS:
We conducted a clinical trial in which 622 participants were randomized to receive 400µg FA, 800µg FA, 3g creatine, 3g creatine+400µg FA, or placebo daily. All participants received an As-removal filter upon enrollment, and were followed for 24 weeks. After the 12th week, half of the two FA groups were switched to placebo to evaluate post-treatment bAs patterns.
RESULTS:
Linear models with repeated measures indicated that the decline in ln(bAs) from baseline in the 800µg FA group exceeded that of the placebo group (weeks 1-12: β= -0.09, 95% CI= (-0.18, -0.01); weeks 13-24: FA continued: β= -0.12, 95% CI= (-0.24, -0.00); FA switched to placebo: β= -0.14, 95% CI= (-0.26, -0.02)). There was no rebound in bAs related to cessation of FA supplementation. Declines in bAs observed in the remaining treatment arms were not significantly different from those of the placebo group.
CONCLUSIONS:
In this mixed folate deficient/replete study population, 12 and 24 week treatment with 800µg (but not 400µg) FA lowered bAs to a greater extent than placebo; this was sustained 12 weeks after FA cessation. In future studies, we will evaluate whether FA and/or creatine altered As methylation profiles.
