Canadian moms mostly stick to vitamin D rules for breastfed infants and young children, study finds

By Pooja Toshniwal PahariaReviewed by Susha Cheriyedath, M.Sc.Apr 2 2024

In a recent study published in The Journal of Nutrition, researchers assessed vitamin D supplementation adherence among breastfed babies (≤12 months) and children (>12 months).

Canada's dietary policy recommends 400 IU (10 µg) of vitamin D daily for breastfed newborns and small children to maintain optimal vitamin D levels. The conservative approach is due to breastmilk's low D vitamin content and the limited food sources in the diets of breastfed newborns and kids who continue nursing for more than 12 months. Certain foods, like infant formula and cow milk, are enriched with vitamin D; however, young children aged one to three years do not receive them adequately. Vitamin D supplement use rates are higher among the western regions, the Yukon, and the Northwest Territories.

Study: Adherence to vitamin D supplementation recommendations for breastfed infants and young children: an analysis of Canadian Community Health Survey data cycles 2015 to 2018. Image Credit: HTeam / Shutterstock

About the study

The present study examined vitamin D administration compliance and frequency for partially or entirely breastfed babies.

The primary goal was to describe vitamin D supplement adherence rates and frequencies for breastfed infants aged ≤1.0 years. The secondary goal was to assess vitamin D supplement use among individuals receiving breastmilk after the first year of birth. The researchers also examined sociodemographic characteristics influencing vitamin D supplement adherence to inform population health policies.

The team examined the Canadian Community Health Survey (CCHS) data for 2015–16 and 2017–18 and maternal experience data for breastfed children born between 2012 and 2018. During the study, they eliminated data from mothers of children born in 2010 and 2011 and mothers of infants under six months. They also eliminated babies born between 2012 and 2018 due to inadequate data on breastfeeding and vitamin D administration frequency.

The researchers obtained CCHS data telephonically and in-person, with the possibility of an in-person follow-up later. They collected data on maternal experiences (such as breastfeeding habits and D vitamin supplementation) from female respondents aged between 15 and 55 who delivered babies between 2010 and 2018. They investigated whether the child received vitamin D supplements and the supplementation frequently.

The team analyzed weighted data based on breastfeeding history (exclusively for six months and continuing, partially for six months, and continuing and discontinued for less than six months). They utilized multivariate logistic regressions to calculate the odds ratios (OR) for the study, controlling for the mother's age, body mass index (BMI), race, ethnicity, education, residential location, household income, source of income, and immigrant status.

Results

The mean maternal age was 31 years. The maternal proportion entirely breastfeeding their infants for more than six months was 40% (n=2,752), while that of mothers practicing partial breastfeeding their child for six months and continued was 31% (n=2,133). The percentage of mothers who stopped breastfeeding after six months of age was 29% (n=2,194).

Among participants, 87% reported providing their child (≤12 months) vitamin D supplements, with 83% doing so daily or almost every day, 12% doing so one to two times weekly, and 4.30% doing so less than one time per week. Participants who had ceased nursing for less than six months had poorer education and income, were new immigrants, or had an elevated pre-pregnancy BMI and had lower adjusted chances of adherence. Western provinces had greater odds of adherence. Fifty-eight percent of participants who nursed their infants over 12 months (n=2,312) provided them with vitamin D supplements daily or almost daily.

The study indicated a higher proportion of moms who fully or partially nursed their kids to six months and continued giving vitamin D supplements than those who quit nursing at six months or less. Infants who quit nursing for ≤6 months were more likely to receive vitamin D supplements, with 88% using it between birth and 12 months.

In 2015, more mothers provided vitamin D pills than in 2012, particularly in western regions. The likelihood of supplementing with vitamin D to infants aged 12 months or younger varies by maternal variables, including breastfeeding stopped ≤6 months, lower maternal age, single, unmarried, less educational attainment, First Nations identities, higher BMI, recent immigration, living in Atlantic regions, and below median income. Children born in the 2015 to 2017 period and those living in the West had higher adjusted probabilities of adherence.

The study showed that while breastfed infants adhere to vitamin D supplementation at a high rate, 27% of moms do not. Adherence falls during 12 months, and more marketing may be required, especially for mothers of new immigrants or those with lower socioeconomic levels. Less than 60% of breastfed children continue to receive vitamin D supplements beyond their first year of birth. Despite this, 87% of women supplement with vitamin D throughout the first year, and 90% of newborns are breastfed partially or entirely for six months and beyond. Stopping breastfeeding, having a lower adjusted household income than the median, worse educational accomplishments, a higher BMI, and recent immigration to Canada are related to reduced compliance.