New research published in BMC Public Health investigated how climate change–sensitive micronutrients, such as iron, zinc, and vitamin A, in children’s diets are linked to undernutrition.
The researchers in Germany, Kenya and the United States emphasized the need for “dietary diversification and climate-resilient production as adaptation priorities to maintain access to bioavailable micronutrients for young children”.
“Our findings align with the growing body of evidence that climate variability is already impacting food and nutrition security in Kenya,” they wrote.
“Promoting diversified diets that integrate both climate-resilient crops and sustainable sources of aquatic protein is critical to safeguarding child nutrition under ongoing climate change.”
How is climate change causing under nutrition?
Undernutrition is already a major public health challenge in low- and middle-income countries, especially among children aged 6–23 months, who experience rapid growth and rely on nutrient-dense complementary foods. In Kenya in particular, 22% of children under five are stunted, 11% are underweight, and 4% suffer from wasting.
Extreme weather such as global warming, droughts, floods, and shifting precipitation is worsening the problem of undernutrition, and research has identified climate change as a severe risk to food security and nutrition, predicted to cause widespread and long-lasting food insecurity and malnutrition for millions of people.
Environmental shifts caused by climate change disrupt agriculture, reducing the availability of nutrient-rich foods, including climate-sensitive micronutrients like iron, zinc, selenium and vitamin A. This happens due to higher CO₂ levels lowering nutrient concentrations in staple crops; soil degradation, erosion, and disrupted microbial activity reducing nutrient update by plant roots; and temperature changes reducing crop yield and forcing farmers to produce safer, less varied crops.
These climate sensitive micronutrients are crucial for child growth and immunity, yet research has found that rising greenhouse gases may reduce these nutrients in major crops by 3–15%.
In Kenya, the majority of the population depends on small-scale, rain-fed farming, undernutrition risks are increasing as temperatures, which have risen by about 1 °C over the past 40 years, are forecast to increase by another 1.5–3 °C by mid-century.
Impact of climate change on micronutrients and child growth in rural Kenya
The researchers analyzed data from a previous cluster-randomized controlled trial, which included mother-child pairs in Siaya County, Kenya, between July and December 2021. They randomly selected 662 households with 683 mother-child pairs.
Participating children were measured for weight and height twice using calibrated equipment, recording recumbent length for children under 24 months or shorter than 85 cm. Researchers calculated weight-for-height, weight-for-age, and height-for-age z-scores according to WHO standards, defining wasting, underweight, and stunting.
They assessed children’s habitual dietary intake over six months using an African-specific Food Questionnaire (AFPQ), which categorized 134 foods into 29 groups, allowing the researchers to calculate energy and nutrient intake. They identified dietary patterns associated with climate-sensitive micronutrients (iron, zinc, selenium, vitamin A) using reduced-rank regression (RRR).
Results found that participating boys had poorer nutritional status than girls, meaning they were lighter, thinner, and shorter for their age, even though boys and girls consumed similar amounts of nutrients.
The researchers noted that the observed sex differences align with previous research documenting poorer growth outcomes among boys in early childhood.
Boys have higher basal metabolic rates and greater energy and protein requirements during infancy and early childhood compared to girls, making them more susceptible to growth faltering when diets are marginal in energy or micronutrients.
Furthermore, boys in the current study were more likely to consume red meat and less likely to eat roots, tubers, and eggs, all of which can be sources of energy, high-quality protein, and bioavailable micronutrients, therefore the reduced diet diversity could be linked to reduced growth outcomes.
It has also been suggested in previous research that in resource-constrained households, daughters may receive more consistent caregiving and feeding.
Overall, eating patterns also revealed that girls who followed healthier, more diverse diets had better body weight and were less likely to be too thin, while boys showed no clear growth benefit from the same diets. The researchers concluded that dietary patterns did not improve children’s height, suggesting that long-term growth problems start earlier and are harder to fix with diet alone.
“The observed dietary patterns—rich in vegetables and legumes—reflect food groups whose production and availability are particularly vulnerable to rising temperatures, recurrent droughts, and carbon emissions,” wrote the researchers. “Consequently, promoting diversified diets that integrate both climate-resilient crops and sustainable sources of aquatic protein is critical to safeguarding child nutrition under ongoing climate change.”
They concluded that results should inform several key strategies, including promoting diverse and nutrient-rich diets to improve child nutrition, tailoring gender-sensitive interventions to address the specific needs of boys and girls, and the implementation of nutrition education programs tailored to local contexts to enhance nutrient adequacy and support healthy growth in young children.
Source:BMC Public Health; doi: https://doi.org/10.1186/s12889-026-26265-z; “Reduced rank regression-derived dietary patterns related to climate-sensitive micronutrients and their associations with child undernutrition among young children in rural Kenya: findings from the ALIMUS study.” Authors: Kihagi, G. W. Et al.
