Assessment of Dietary Vitamin D, Vitamin K and Calcium Intake of Portuguese Women of Childbearing age living in Switzerland

Background: The lack of sun plays a major role in vitamin D deficiency, particularly among vulnerable groups, including migrants and women. Vitamin D and calcium are crucial nutrients for optimal bone health, heart function and muscle contraction. Recent studies suggest that the two micronutrients alone do not appear to be as beneficial as when their intake is coupled with vitamin K.
Therefore, it is necessary to prevent their deficiencies. To this date, we observe a deficit of culturally sensitive methods for assessing dietary intake. The aim of this study was to estimate the dietary vitamin D, vitamin K and calcium intake among Portuguese women of childbearing age living in Switzerland.
Methodology: A food frequency questionnaire was developed and dministrated. A comparative method, a 24-hour dietary recall, was applied twice, over two non-consecutive days. The same methodology was applied to and compared with two control groups: Portuguese women living in Portugal and Swiss women living in Switzerland. Data were analysed using Microsoft Excel® version
15.0, 2013, Nutritional. Software® version 1.32.44, 2012 and IBM SPSS®, version 24.0, 2016 for windows.
Results: Portuguese in Switzerland had the lowest vitamin D intake (6.04 μg /day) from food. When dietary supplements were considered, significant differences were found between the Swiss (11.1 μg) and Portuguese groups (7.04 μg) (p = 0.004). Regarding vitamin K, the focus group had the lowest intake (102.20 μg/day). Concerning calcium, the Swiss group was the only one achieving the daily recommendations (1355.14 mg) and significant differences were found between the Swiss and the Portuguese groups (p < 0.001).
Conclusion: In the present study the three participant groups had a deficient intake of vitamin D and only the Swiss group had an adequate calcium intake. Vitamin K intake did not seem to be a concern in terms of dietary deficiencies for all the groups of participants.