Changes in knowledge, attitudes and behaviours towards vitamin D and sun exposure of parents of infants and young children in New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Nutrition and Dietetics at Massey University, Albany, New Zealand

Abstract

Background: Vitamin D deficiency can have serious health implications in early life, with severe deficiency resulting in rickets. Vitamin D deficiency has also been linked to extra-skeletal conditions during pregnancy, infancy and childhood. Vitamin D is synthesised following exposure to ultraviolet radiation; with factors impacting synthesis increasing the risk of deficiency. Therefore, parents’ knowledge about vitamin D is important for optimal vitamin D status in early life. In 2012 and 2013, the Ministry of Health (MoH) released a Consensus Statement on Vitamin D and Sun Exposure, followed by a Companion Statement for Pregnancy and Infancy with subsequent public health messaging. However, there is limited information on parents’ vitamin D knowledge in New Zealand. Aim: To determine the impact of these statements on vitamin D and sun exposure knowledge, attitudes and behaviours of parents of infants and young children in New Zealand. Methods: This ecological study utilised a cross-sectional questionnaire to collect data at two time points - 2009 and 2021 to compare knowledge, attitudes and behaviours and assess the impact of the MoH statements. Inclusion criteria included: youngest child <5 years, living in New Zealand, and understanding written English. Results: The analysis included 9,834 parents (2009 N=8,032, 2021 N=1,802). Knowledge of vitamin D roles was similar; however, a higher proportion of parents (48.2%) in 2021 correctly identified the role of vitamin D in immunity compared to 2009 (29.1%). Most parents lacked knowledge of high-risk factors for deficiency, including exclusive breastfeeding (98.1%, 95.1%) and darker skin colour (92.9%, 77.5%). Health professionals were not the main source of information (15.8%, 24.8%), and low advice rates on supplementation and sun exposure were reported. In 2021, 60.2% of parents reported health professionals or the MoH, and 24.5% reported the media or social media as their preferred source of information on vitamin D. Safe sun exposure practices were performed frequently in children during the summer in 2009 and 2021. Most parents (86.9%) in 2021 did not know current vitamin D and sun exposure recommendations. Conclusion: Overall, the impact of the MoH statements and subsequent public health messaging on parents’ knowledge has been minimal. To improve parents’ knowledge, the MoH could utilise social media to communicate public health information more effectively.