Sunlight and vitamin D intake may affect vitamin D insufficiency risk among infants aged 6 to 12 months, according to research published in Family Practice. Infants with anemia, low iron levels, and those who are breastfed are more likely to demonstrate vitamin D insufficiency, but these variables did not achieve statistical significance in the multivariate analysis, the report shows.
Researchers enrolled 120 infants (mean age, 7.24 months) in a cross-sectional study to examine variables associated with vitamin D insufficiency. Full-termed infants, aged 6 to 12 months, underwent blood sampling, demographic assessment, and a 24-hour nutritional assessment. The team recorded 25-hydroxyvitamin (OH) D and hemoglobin (Hb) levels and assess associations between vitamin D insufficiency and anemia as a primary outcome measure. Secondary outcome measures included risk factors for vitamin D insufficiency.
Among the infants included in the study, 35 (29.4%) received an anemia diagnosis and 34 (28.3%) were vitamin D deficient. Iron deficiency anemia was the most common underlying cause of anemia found, constituting 82.8% of those diagnosed.
The mean 25(OH)D levels in the 35 infants with anemia were significantly lower compared with the 84 infants without anemia, making vitamin D insufficiency more prevalent among the infants with anemia (P=0.031). Similarly, investigators noted anemia in 45.4% of participants with vitamin D insufficiency compared with 23.3% of infants who were vitamin D sufficient.
Multivariate regression models found that less than 15 minutes of sunlight exposure per day was a significant risk factor for vitamin D insufficiency (odds ratio [OR], 3.84; 95% CI, 1.23-12.00; P =0.020). Doubling vitamin D intake significantly reduced vitamin D insufficiency risk (OR, 0.37; 95% CI, 0.20– 0.74; P = 0.004). Anemia, breastfeeding and low iron intake did not demonstrate any significant associations with vitamin D insufficiency following multivariate analysis, but infants with these variables were more likely to have vitamin D insufficiency, according to the report.
“Infants require optimal sunlight exposure and vitamin D intake to prevent [vitamin D insufficiency],” according to the study authors. “Given that there are limited recommendations on appropriate sunlight exposure for infants and low vitamin D in natural food sources, including breast milk, vitamin D supplementation should be provided.”
Study limitations include a small sample size, single center design, a disproportionate representation of families with high incomes, and failure to obtain iron status markers.
Boonrusmee S, Kasemsripitak S, Navykarn T, Jaruratanasirikul S. Association between anaemia and vitamin D insufficiency among 6- to 12-month-old infants: implications for clinical practice. Fam Pract. Published online April 4, 2023. doi:10.1093/fampra/cmad033