Sazawal S, Dhingra U, Hiremath G, et al. Effects of Bifidobacterium lactis HN019 and prebiotic Oligosaccharide added to milk on iron status, anemia, and growth among children 1 to 4 years old. J Pediatr Gastroenterol Nutr. 2010 Jun 30. [Epub ahead of print]
Double-blind, randomized, controlled, community-based trial.
624 children aged 1–4 years in New Dehli were randomized to receive either control or fortified milk. Hematological parameters were evaluated at baseline and end of study. Height and weight were measured at baseline, mid-study and end of study.
Study Medication and Dosage
Participants received either control milk or milk fortified with an additional 1.9 x107 colony-forming units of Bifidobacterium lactis HN019 and 2.4g/day of prebiotic oligosaccharides for 1 year.
The consumption of the prebiotic- and probiotic-fortified milk reduced the risk of being anemic and iron-deficient by 45%, and increased weight gain by 0.13 kg/year when compared to controls.
According to the World Health Organization (WHO), 47.4% of preschool-age children and 25.4% of school-age children worldwide are anemic. Approximately half these anemias are thought to be due to iron deficiency. In the United States, WHO does not consider anemia to be a public health problem, as only 3.1% of preschool age children were found to be anemic.1 However, poor, minority and immigrant children and toddlers are still at risk for iron deficiency with and without anemia.2
This study by Sazawal points to a potential solution to the global concern of nutritional deficiencies, and it specifically provides a new insight to anemia treatment and prevention. The beneficial effects of probiotics have been well-documented in the treatment of diarrhea, though it seems they may have a more far-reaching physiological impact than previously thought.3 In a concurrent study, prebiotic- and probiotic-fortified milk reduced the number of episodes of dysentery, severe illness, and high fever. It has also been shown that a healthy ratio of beneficial gut bacteria in infancy is protective against overweight and obesity later in life,4, 5 and associated with a decreased risk of gestational diabetes.6
With respect to the role of probiotics in treating anemia, related studies show that children given an iron-fortified fermented milk beverage with supplemental Lactobacillus acidophilus had higher red blood cell measurements and were more likely improve hemoglobin levels with increased iron intake.7 These studies provide evidence to support the use of both Lactobacillus acidophilus and Bifidobacterium lactis to prevent anemias in children.
What may be more relevant to our patients in the United States and the growing trend toward obesity is the link between increased BMI and decreased iron status.
What may be more relevant to our patients in the United States and the growing trend toward obesity is the link between increased BMI and decreased iron status. According to a 2004 Pediatrics article, children who are overweight and obese are approximately twice as likely to be iron-deficient.8 It is reasonable to assume that supplementing children with probiotics will confer many benefits, including a stronger immune system, as well as decreasing risks of both obesity and iron deficiency. One explanation is that the large amounts of calcium in milk may have a protective effect against the development of overweight, type 2 diabetes, metabolic syndrome, and ischemic cardiovascular disease by reducing the absorption of fat in the intestines.9 It may be worth considering a similar intervention of fortified milk to obese children to address not only the development of such conditions, but also the associated risk of iron deficiency.
While anemia certainly affects cognitive development, Lozoff et al have also shown a correlation between iron deficiency both with and without anemia and poorer infant behaviors.10 A relatively simple intervention such as the one described in this study could have profound effects on the social and emotional development of infants.
This study not only highlights the importance of intestinal bacteria, but serves as a reminder of the importance of prebiotics as well. A trial of infant formula with probiotics only did not improve infant growth, and Laparra et al showed that the addition of inulin as a prebiotic to Lactobacillus acidophilus increased iron absorption from beans, but decreased iron absorption when added to Bifidobacterium infantis.11, 12
Probiotics continue to be a safe and noninvasive intervention worth considering not only in cases of gastrointestinal disturbances but also as an adjunctive therapy in cases anemia or where there is a risk of anemia.