Advertisement
Advertisement
Study decoded · health · Emerging
Mother's Body Weight Linked To Child Hemoglobin In Peru Study
16,973 Peru kids+0.72 g/dL hemoglobinNo anemia linkCross-sectional data
A national Peruvian survey of 16,973 children published in PLOS One found that children of mothers with obesity had hemoglobin levels 0.72 g/dL higher than children of normal-weight mothers, yet maternal body mass index had no measurable link to whether a child was actually diagnosed with anemia.
Researchers analyzed the 2024 Peruvian Demographic and Family Health Survey, covering 16,973 children aged 6 to 59 months and their mothers out of 17,790 originally identified. Average child age was 32.2 months, 51.0% were male, and average maternal BMI was 27.9 kg/m2, with 40.1% of mothers classified as overweight. Overall, 29.9% of children had anemia and average hemoglobin was 11.2 g/dL. After adjusting for confounders, children of mothers with obesity had hemoglobin 0.72 g/dL higher than children of normal-weight mothers (95% CI 0.23 to 1.22), and each 1 kg/m2 increase in maternal BMI tracked with a 0.07 g/dL increase in child hemoglobin (95% CI 0.03 to 0.11). Maternal BMI, grouped or continuous, showed no measurable association with anemia prevalence itself.
Hemoglobin is the protein in red blood cells that carries oxygen, and anemia is diagnosed only once hemoglobin falls below a fixed cutoff. The study authors propose that a mother's higher BMI may reflect greater household food security and better access to foods rich in bioavailable iron, rather than a direct biological effect of body fat on a child's blood. They note the hemoglobin change was real but apparently too small, on average, to push enough children across the diagnostic line into the anemia category.
Child Hemoglobin by Maternal Weight Status: +0.72 g/dL Higher With Maternal Obesity
Data Panel
- Who
- 16,973 Peruvian children aged 6-59 months and their mothers, from the 2024 national ENDES survey
- Design
- Cross-sectional analytical study using nationally representative survey data with complex sampling, Poisson and linear regression models
- Dose
- Not applicable; exposure was maternal BMI category (underweight, normal, overweight, obesity) and continuous BMI in kg/m2
- Primary result
- Maternal obesity vs normal weight: child hemoglobin +0.72 g/dL (95% CI 0.23 to 1.22); each 1 kg/m2 higher maternal BMI: +0.07 g/dL child hemoglobin (95% CI 0.03 to 0.11)
- Secondary
- No significant association between maternal BMI (categorical or continuous) and child anemia prevalence after adjustment. Overall anemia prevalence was 29.9%, average hemoglobin 11.2 g/dL, average maternal BMI 27.9 kg/m2.
- Funding / conflicts
- The authors received no specific funding for this work.
This is a single-timepoint survey, so it cannot establish whether maternal weight causes the hemoglobin difference or merely tracks with it. Underweight mothers made up only 0.9% of the sample, limiting what the data can say about that group despite prior research flagging it as higher-risk. Researchers also could not account for iron supplementation, breastfeeding type or child dietary diversity due to missing data.
Dr. Axe's Take
A 0.72 g/dL hemoglobin difference tied to maternal obesity is not a reason to chase a higher number on the scale. The researchers themselves say this likely reflects food access, not a metabolic benefit of excess body fat. What I take from this is that household food security and iron-rich food availability during complementary feeding matter more than a mother's weight class. I would focus on getting iron-rich foods like grass-fed beef liver, egg yolks and legumes into a toddler's diet consistently, paired with vitamin C-rich foods like citrus or bell peppers to help iron absorption. If bloodwork shows low hemoglobin, work with a pediatrician on iron repletion rather than assuming maternal weight explains it.
— Dr. Axe