Mark Sean, Gray-Donald Katherine, Delvin Edgard E, O'Loughlin Jennifer, Paradis Gilles, Levy Emile, Lambert Marie
Department of Dietetics and Human Nutrition, McGill University, Montréal, Québec, Canada.
Clin Chem. 2008 Aug;54(8):1283-9. doi: 10.1373/clinchem.2008.104158. Epub 2008 Jun 12.
Adequate vitamin D status is important for bone growth and mineralization and has been implicated in the regulation of autoimmunity, metabolic function, and cancer prevention. There are no reports of population-based studies on the vitamin D status of Canadian youth, a population with mandatory fortification of foods.
We measured plasma 25-hydroxyvitamin D [25(OH)D], the best indicator of vitamin D status, in a school-based cross-sectional sample of representative French Canadian youth (n = 1753) ages 9, 13, and 16 years living in Québec (latitude: 45 degrees-48 degrees N). Blood samples were collected from January to May 1999. We defined 25(OH)D deficiency as < or = 27.5 nmol/L, hypovitaminosis as < or = 37.5 nmol/L, and optimal as > 75.0 nmol/L.
More than 93% of youth in each age and sex group had suboptimal 25(OH)D concentrations. The prevalence of 25(OH)D deficiency increased with age in both sexes (P < 0.0001). It was 2%, 3%, and 13% in 9-, 13-, and 16-year-old boys and 2%, 8%, and 10% in 9-, 13-, and 16-year-old girls. Girls with higher body mass index and girls from households with lower income had lower 25(OH)D concentrations. These effects were not observed in boys.
Inadequate vitamin D status is a potentially serious public health problem among children and adolescents in Québec. Youth living at high latitudes in countries with and without mandatory fortification of vitamin D are likely at heightened risk of 25(OH)D deficiency. These results call for renewed efforts to ensure adequate vitamin D intake among growing children and adolescents.
充足的维生素D水平对骨骼生长和矿化至关重要，并且与自身免疫调节、代谢功能及癌症预防有关。对于加拿大青少年这一食品强制强化的人群，尚无基于人群的维生素D水平研究报告。
我们在魁北克（北纬45度至48度）对年龄分别为9岁、13岁和16岁的具有代表性的法裔加拿大青少年（n = 1753）进行了一项基于学校的横断面抽样研究，测量了血浆25-羟基维生素D [25(OH)D]，这是维生素D水平的最佳指标。血样于1999年1月至5月采集。我们将25(OH)D缺乏定义为≤27.5 nmol/L，维生素D不足定义为≤37.5 nmol/L，最佳水平定义为>75.0 nmol/L。
每个年龄和性别组中超过93%的青少年25(OH)D浓度未达最佳水平。25(OH)D缺乏的患病率在男女两性中均随年龄增长而升高（P < 0.0001）。9岁、13岁和16岁男孩的患病率分别为2%、3%和13%，9岁、13岁和16岁女孩的患病率分别为2%、8%和10%。体重指数较高的女孩以及来自低收入家庭的女孩25(OH)D浓度较低。在男孩中未观察到这些影响。
维生素D水平不足在魁北克的儿童和青少年中可能是一个潜在的严重公共卫生问题。在有或没有强制强化维生素D的国家，生活在高纬度地区的青少年可能25(OH)D缺乏风险更高。这些结果呼吁重新努力确保成长中的儿童和青少年摄入充足的维生素D。
