Serum Vitamin B12 Concentration in Dietary Deficiency

The Microbiota and Malnutrition: Impact of Nutritional Status During Early Life

According to the developmental origins of health and disease hypothesis, our health is determined by events experienced in utero and during early infancy. Indeed, both our prenatal and postnatal nutrition conditions have an impact on the initial architecture and activity of our microbiota. Recent evidence has underlined the importance of the composition of the early gut microbiota in relation to malnutrition, whether it be undernutrition or overnutrition, that is, in terms of both stunted and overweight development. It remains unclear how early microbial contact is linked to the risk of disease, as well as whether alterations in the microbiome underlie the pathogenesis of malnutrition or are merely the end result of it, which indicates that thequestion of causality must urgently be answered. This review provides information on the complex interaction between the microbiota and nutrition during the first 1,000 days of life, taking into account the impact of both undernutrition and overnutrition on the microbiota and on infants' health outcomes in the short- and long-term.

Diarrhea and Novel Dietary Factors Emerge as Predictors of Serum Vitamin B12 in Panamanian Children

Background

The role of gastrointestinal infection as a factor determining vitamin B12 status in populations with low intake of animal-source foods is unclear.

Objective

To determine dietary adequacy and serum concentrations of vitamin B12 in an extremely impoverished indigenous population of Panamanian children aged 12 to 60 months, and to identify predictors of both dietary and serum vitamin B12.

Methods

A previous community-based survey provided the usual dietary intake and personal, household, and infection (Ascaris and diarrheal disease) information for 209 weaned children. Serum vitamin B12 was assayed using electrochemiluminescence for 65 of these children. Children with adequate or inadequate dietary vitamin B12 intake were compared, and predictors of dietary and serum vitamin B12 were identified using step-wise regression analyses of one index child per household.

Results

Dietary vitamin B12 intake was inadequate in 43% of children; these children were poorer, had less frequent diarrhea, and obtained a higher percentage of their energy from carbohydrate than children with adequate intake. Energy intake positively predicted dietary vitamin B12 intake. In contrast, serum vitamin B12 concentrations were normal in all but 3% of the children. Serum vitamin B12 was positively associated with weekly servings of fruit, corn-based food, and ñame (a traditional starchy food), but not with animal-source foods. Finally, serum vitamin B12 was not associated with Ascaris intensity but was lowered with increasing frequency of diarrhea.

Conclusions

Although inadequate dietary intake of vitamin B12 was common, most serum values were normal. Nevertheless, diarrheal disease emerged as a negative predictor of serum vitamin B12 concentration.

Vitamin B12 deficiency as a worldwide problem

Pernicious anemia is a common cause of megaloblastic anemia throughout the world and especially in persons of European or African descent. Dietary deficiency of vitamin B12 due to vegetarianism is increasing and causes hyperhomocysteinemia. The breast-fed infant of a vitamin B12-deficient mother is at risk for severe developmental abnormalities, growth failure, and anemia. Elevated methylmalonic acid and/or total homocysteine are sensitive indicators of vitamin B12-deficient diets and correlate with clinical abnormalities. Dietary vitamin B12 deficiency is a severe problem in the Indian subcontinent, Mexico, Central and South America, and selected areas in Africa. Dietary vitamin B12 deficiency is not prevalent in Asia, except in vegetarians. Areas for research include intermittent vitamin B12 supplement dosing and better measurements of the bioavailability of B12 in fermented vegetarian foods and algae.