Abstract
Objectives
Health Canada recommends vitamin D supplements (10 ώg/d) for Canadians aged ≥50 years, but no data are available on adoption of this recommendation. Accordingly, this study was conducted to determine the current use of vitamin D supplements among British Columbian adults 50 years and over, and to explore relationships among vitamin D supplement use, socio-demographic variables, and knowledge, attitudes and beliefs about vitamin supplementation.
Methods
A population-representative stratified sample, recruited by random-digit dialling, completed a telephone-administered survey in late fall of 2008. Respondents provided details on supplements used in the past month (dosage, frequency, etc.) and demographic data, and responded to statements reflecting health beliefs about supplements, from which a Supplement Health Belief score was calculated. Eligible non-respondents indicated their age, sex, and whether they had used a supplement within the past month.
Results
Similar proportions of participants (n=969) and non-respondents (n=1,027) reported any supplement use in the past month. Among participants, 60% had used a vitamin D supplement (median intake among supplement users was 10 ώg/d) and 3% exceeded the Tolerable Upper Intake Level of 50 ώg/d. In multivariate analysis, vitamin D supplementation was significantly associated with female sex, not smoking, higher educational attainment, having a health care professional recommend supplement use, and a higher Supplement Health Belief score.
Objectifs
x: Although most older adults used a vitamin D supplement, further dissemination of this recommendation is needed.
Key words: Vitamin D, supplement, older people, health beliefs, British Columbia, survey
Résumé
Objectifs
Santé Canada recommande la prise de suppléments de vitamine D (10 ώg/j) pour les Canadiens de 50 ans et plus, or il n’existe pas données ayant trait à l’adoption de cette recommandation. Cette étude a donc été effectuée afin de déterminer l’utilisation de suppléments de vitamine D des Britanno-colombiens de 50 ans et plus, et d’étudier les relations existant entre la prise de suppléments de vitamine D, les variables socio-démographiques ainsi que les connaissances, attitudes et croyances concernant la supplémentation en vitamines.
Méthodes
Un échantillon stratifié représentatif de la population et recruté au moyen d’appels téléphoniques aléatoires a répondu à une enquête par téléphone à la fin de l’automne 2008. Les répondants ont détaillé l’utilisation de suppléments dans le mois écoulé (dose, fréquence, etc.) en plus de fournir des données démographiques et de répondre à des énoncés reflétant leurs croyances en santé sur les suppléments, à partir desquels un indice de croyances en santé sur les suppléments a été calculé. Les répondants non admissibles ont indiqué leur âge, sexe, et s’ils avaient utilisé un supplément dans le mois écoulé.
Résultats
En proportion identique, les participants (n=969) et non-répondants (n=1 027) ont rapporté l’utilisation de divers suppléments dans le mois écoulé. Des participants, 60 % ont utilisé un supplément de vitamine D (l’apport médian parmi les utilisateurs de suppléments était de 10 ώg/j) et 3 % ont dépassé l’Apport maximal tolérable de 50 ώg/j. L’analyse multivariée a montré que la supplémentation en vitamine D était significativement liée aux caractéristiques suivantes: sexe féminin, non fumeur, niveau d’instruction supérieur, avoir un professionnel de la santé ayant conseillé la prise d’un supplément et un indice de croyances en santé sur les suppléments plus élevé.
Conclusion
Même si la plupart des adultes plus âgés prennent des suppléments de vitamine D, il est nécessaire de diffuser plus largement cette recommandation.
Mots clés: vitamine D, suppléments, personnes âgées, croyances en santé, Colombie Britannique, enquête
Footnotes
Acknowledgements: The authors are indebted to Jung-Un Choi for her technical assistance and Roch Duhamel at Harris Decima for his technical support. This research was supported by a grant obtained through the Vitamin Class Action settlement.
Conflict of Interest: None to declare.
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