A new study from Canada suggests that a short-term supplementation with vitamin C may improve mood and reduce psychological distress for acutely hospitalized patients with a high prevalence of insufficient vitamin C supply.
In the randomized controlled trial, the mood state and psychological distress of 52 patients at medical or surgical hospital units who received either 500 mg vitamin C twice daily or 5000 IU vitamin D daily for an average of 8 days were measured (1). The results showed that at the beginning of the study, 73% of patients had insufficient plasma total vitamin C concentrations (below 28.4 micromoles/liter) and 29% had deficient levels (below 11.4 micromoles/liter); 79% of patients had subnormal plasma vitamin D concent-rations (below 75 nanomoles/liter). By the end of the study, the plasma total vitamin C concentration of all the patients who received vitamin C increased to the normal range. In addition, they showed a 71% reduc-tion in mood disturbance and a 51% reduction in psychological distress, as measured by questionnaires. The plasma 25-hydroxyvitamin D concentrations of the patients receiving vitamin D, however, did not increase to the normal range and they showed no significantly improvement in mood or reduction of distress.
The researchers commented that the findings for vitamin C support the results of earlier studies indicating that the vitamin plays an important role in brain metabolism (2). Moreover, not clinically manifest vitamin C deficiency has shown to induce fatigue and mood disturbance (3). No conclusions may be drawn regarding the potentially positive effects of vitamin D because the dose and duration of therapy were insufficient to raise 25(OH)D concentrations to the normal range. Furthermore, vitamin D is known to be essential for brain functions (4) and insufficient supply has been linked to cognitive dysfunction (5) and depression (6). Insuf-ficient vitamin C and D status is highly prevalent among acutely hospitalized patients who experience emotional distress for many reasons (3, 7). A simple correction of their vitamin C and D deficiency could account for such rapid and dramatic improvements in psychological well-being, the scientists concluded.