No association between vitamin C and E supplementation and grip strength over 5 years: the Colaus study.

PURPOSE

To assess the cross-sectional and longitudinal association between self-reported vitamin C + E dietary supplementation and markers of grip strength and frailty in community-dwelling Swiss adults.

METHODS

Population-based study including 3277 participants (1722 women) aged 40-80 years at baseline. The associations between vitamin C + E dietary supplementation and grip strength were examined cross-sectionally and after a follow-up of 5.2 years on average.

RESULTS

There were 253 (7.7%) self-reported vitamin C + E supplement users. Female users had significantly lower grip strength than non-users (average ± standard deviation: 24.3 ± 6.1 versus 25.6 ± 6.1 kg, respectively). However, the association disappeared after multivariate adjustment (24.7 ± 0.5 versus 25.6 ± 0.1 kg, for users versus non-users, respectively). No differences were found in men regarding grip strength. No differences were found in the highest quintile of grip strength or prevalence of low grip strengthin in users versus non-users during cross-sectional analysis for both genders. After 5.2 years of follow-up, no associations were found between vitamin C + E supplementation and change in grip strength for raw values (difference between baseline and follow-up: 1.2 ± 5.0 versus 0.4 ± 5.2 kg for female and 0.6 ± 6.5 versus 1.1 ± 6.8 kg for male users and non-users, respectively) or after multivariable adjustment (1.2 ± 0.5 versus 0.4 ± 0.1 kg for female and 0.6 ± 0.8 versus 1.1 ± 0.2 kg for male users and non-users, respectively) when taking baseline vitamin C + E supplementation into account. No association was also found for incidence of low grip strength.

CONCLUSION

In a sample of community-dwelling Swiss adults, vitamin C + E supplementation neither improved grip strength nor prevented low-grip strength over a 5-year period.