Dietary patterns according to vitamin supplement use. A cross-sectional study in Switzerland

Background: consumers of dietary supplements (DS) or vitamin-mineral supplements (VMS) have a better health profile than nonconsumers; whether this also applies to healthier dietary patterns has seldom been assessed. We aimed to assess the dietary intake of subjects according to their consumption of DS or VMS. Methods: Cross-sectional, population-based studies conducted in 2009-2012 (3773 participants, 52.4% women, 57.0 ± 10.0 years) and 2014-2017 (2536 participants, 52.4% women, 60.0 ± 10 years) in Lausanne, Switzerland. Dietary intake was assessed via a 97-item food frequency questionnaire. Nutrients, consumption of specific food groups, dietary scores, and compliance with the Swiss nutritional guidelines were compared between VMS/DS consumers and nonconsumers. Results: In 2009-2012, after multivariable adjustment for gender, age, body mass index, education, smoking, country of birth, sedentariness, diet and total energy intake, VMS/DS consumers had a higher score for the "Fruits & vegetables"(-0.09 ± 0.02 vs. 0.15 ± 0.05) dietary pattern and a lower score for the "Fatty & sugary" dietary pattern (0.02 ± 0.02 vs. -0.14 ± 0.04) and had a lower likelihood to comply with the guideline on total fat [odds ratio and 95 %CI: 0.72 (0.57-0.89)] than nonconsumers. In 2014-2017, after multivariable adjustment, no differences (at p < 0.005) were found between VMS/DS consumers and nonconsumers. Conclusion: VMS/DS consumers tend to have healthier dietary choices than nonconsumers. The beneficial effect of VMS and/or DS consumption is decreased, as it does not target subjects who really need them.