The Effects of Vitamin D-Enriched Mushrooms and Vitamin D3 on Cognitive Performance and Mood in Healthy Elderly Adults: A Randomised, Double-Blinded, Placebo-Controlled Trial

Abstract

Despite abundant cross-sectional evidence that low vitamin D status is associated with risk of cognitive decline in ageing, interventional evidence for benefits of vitamin D supplementation is lacking. This study was a 6 month randomised, double-blinded placebo-controlled clinical trial of the effects of vitamin D3 (D3), enhanced vitamin D2 in a mushroom matrix (D2M), standard mushroom (SM) and placebo (PL) on cognition and mood in n = 436 healthy older male (49%) and female volunteers aged ≥ 60 years. Primary end points were change in serum vitamin D metabolites (25-OH-D, 25-OH-D2 and 25-OH-D3), cognitive performance, and mood over 24 weeks. Levels of total 25-OH-D and 25-OH-D3 were maintained in the D3 arm but decreased significantly (p < 0.05) in the remaining arms (D2M, SM and PL). Analysis also revealed differential changes in these metabolites depending on total vitamin D status at baseline. There were no significant effects of treatment on any of the measures of cognitive function or mood. Overall, the results show that daily supplementation of ~600 IU of vitamin D3 was sufficient to maintain 25-OH-D throughout winter months, but in contrast to existing cross-sectional studies there was no support for benefit of vitamin D supplementation for mood or cognition in healthy elderly people.

Keywords: cognitive function; mood; mushroom; vitamin D.

Figure 1

Flow of participants through the trial.

Figure 2

Changes in 25-OH-D (A) and 25-OH-D3 (B) per treatment arm. Error bars represent ±1.5 SE. PL = Placebo, D2M = enhanced vitamin D2 in mushroom, D3 = Vitamin D3, SM = Standard Mushroom.

Figure 3

Changes in 25-OH-D per treatment arms for baseline total 25-OH-D-deficient (<75 nM) and -sufficient subgroups. Error bars represent ±1.5 SE. D2M (enhanced D2 mushroom), D3 (vitamin D3); SM (standard mushroom), and PL (placebo).

Figure 4

Changes in 25-OH-D3 per treatment arms for baseline total 25-OH-D-deficient (<75 nM) and -sufficient subgroups. Error bars represent ± 1.5 SE. D2M (enhanced D2 mushroom), D3 (vitamin D3); SM (standard mushroom), and PL (placebo).