Serum folate and vitamin B12 status in young Brazilian children

Abstract

ObjectiveTo assess the nutritional status of folate and vitamin B12 with anaemia in young children.DesignA cross-sectional study was conducted at the primary health-care centres of four Brazilian cities. Folate and vitamin B12 were assessed by fluoroimmunoassay. Multilevel Poisson regression models were used to explore the association of folate and vitamin B12 status in relation to anaemia in young children.SettingBrazil.ParticipantsChildren (n 460) aged 11 to 15 months.ResultsThe median (interquartile range) of serum folate was 39·7 (28·8–55·3) nmol/l and only four children presented with folate deficiency (<10 nmol/l). Surprisingly, 30·9 % of children presented with serum folate concentrations above the upper limit of detectable values by the commercial kit used for analysis. The frequency of vitamin B12 deficiency (<148 pmol/l) was 15 % and it was inversely associated with the highest tertile of serum folate concentrations (P<0·001). Having high serum folate concentration (≥50·1 nmol/l) and vitamin B12≥148 pmol/l was associated with lower frequency of anaemia in these children (prevalence ratio=0·53; 95% CI 0·30, 0·92).ConclusionsHigh frequency of elevated serum concentration of folate was found among young Brazilian children and 15 % of them had vitamin B12 deficiency. The combination of high serum folate and normal vitamin B12 status was associated with a lower frequency of anaemia in these children. Improvements in the current strategies to promote healthy food-based complementary feeding along with prevention and control of micronutrient deficiencies are recommended to improve children’s health.

Contribution of genetic ancestry and polygenic risk score in meeting vitamin B12 needs in healthy Brazilian children and adolescents

“…A second indicator, such as serum methylmalonic acid (MMA) and/or holo-transcobalamin, should be assessed to improve problems with sensitivity and specificity 81 , which was not evaluated in the present study. The cut-off for vitamin B12 deficiency chosen was < 148 pmol/L, which corroborates other studies 32 , 80 – 83 . However, no consensus exists for a definition of a cut-off point low vitamin B12 levels in children and adolescents 30 , 35 , 80 .…”

“…The mandatory flour fortification with folic acid in Brazil has proved to be effective in increasing serum folate concentrations in children and adolescents 33 but some researchers speculate that excess folate may interfere with vitamin B12 metabolism and may worsen the functional consequences of impaired vitamin B12 deficiency 34 . Although some Brazilian authors suggest that vitamin B12 deficiency is practically nonexistent in children 35 , the screening for vitamin B12 deficiency may be particularly relevant in our population because the combination of high serum folate and normal vitamin B12 status has been associated with a lower frequency of anemia in these children 30 , 32 . Severe deficiency without treatment may lead to high homocysteine levels in Brazilian children 35 .…”

“…Sub-clinical deficiency may affect 2.5–26% of the population, depending on the definition, as the cut-offs are undefined 29 . Studies with children in Brazil have shown different vitamin B12 deficiency rates, such as 3.7% 30 11.7% 31 and 15% 32 . The mandatory flour fortification with folic acid in Brazil has proved to be effective in increasing serum folate concentrations in children and adolescents 33 but some researchers speculate that excess folate may interfere with vitamin B12 metabolism and may worsen the functional consequences of impaired vitamin B12 deficiency 34 .…”

Haematological Parameters in Children with Serum Folate Deficiency

“…Relatively few data on the frequency and diversity of hematologic abnormalities in childhood FD have been reported (4)(5)(6)11,12). Hematologic abnormalities of anemia has been frequently associated with FD, but thrombocytopenia, leucopenia, and pancytopenia are less frequently seen (4)(5)(6)13).…”

The association between altitude and serum folate levels in Tibetan adults on the Tibetan plateau

“…The reported prevalence of folate deficiency varies considerably worldwide due to the different definitions of low serum folate levels, and the population studied. The prevalence of folate deficiency has been reported to be less than 3.2% in children 1 – 3 , 46%, and 3–12% in pregnant or lactating women 4 , respectively, and less than 4% in the healthy population 5 , 6 . In a nutritional survey, Gupta et al discovered a 1.5% prevalence of folate deficiency in schoolchildren aged 6–18 years at high altitudes in Himachal Pradesh 7 , while Osei et al discovered low folic acid concentrations in 67.9% of schoolchildren in Himalayan villages in India 8 .…”