Efficacy of Supplementary Vitamins C and E on Anxiety, Depression and Stress in Type 2 Diabetic Patients: A Randomized, Single-blind, Placebo-controlled Trial

Abstract

Diabetes mellitus as one of the most prevalent endocrine disease is associated with high oxidative stress. Anxiety, stress and depression are common neuropsychiatric features in diabetic patients. Hyperglycemia leads to increased oxidative stress which in turn diminishes antioxidant defense system. On the other hand oxidative stress is the leading cause of depression and anxiety disorders. Thus, it seems that diabetes could accelerate the trend of psychiatric diseases. In this randomized single-blind study, evaluation of the effects of two antioxidants (vitamin C and vitamin E) was done on Stress, depression and anxiety levels in 45 diabetic patients for six weeks. The patients were randomly divided in three groups of vitamin E (400 IU day(-1)), vitamin C (1000 mg day(-1)) and placebo. DASS-21 (Depression Anxiety Stress Scales 21-item) questionnaire items were read to each patient and completed by the main investigator of this study before and after six weeks of supplementation. The scores of depression, anxiety and stress were evaluated separately based on the DASS questionnaire. The results showed a significant decrease in anxiety level (p = 0.005) in vitamin C group compared to other groups but there were no significant differences between groups in terms of changes in stress and depression scores. In conclusion, this study suggests that short-term supplementation of vitamin C is safe and beneficial for reducing anxiety levels in diabetic patients through alleviating oxidative damage.

Does Vitamin C Influence Neurodegenerative Diseases and Psychiatric Disorders?

“…Gautam et al [ 171 ] observed that patients with generalized anxiety disorder had significantly lower Vit C levels in comparison with healthy controls, whereas 6-week vitamins supplementation (vitamin C accompanied with A and E) led to a significant reduction in anxiety scores [ 171 ]. Mazloom et al [ 190 ], in turn, showed that short-term supplementation of Vit C (1000 mg/day) reduced anxiety levels (evaluated basing on Depression Anxiety Stress Scales 21-item) in diabetic patients. This effect was exerted through alleviating oxidative damage.…”

Vitamins and Type 2 Diabetes Mellitus

“…Diabetes has also been associated to periodontal disease and vitamin C supplementation together with dental maneuvers has been shown to improve chronic periodontitis in newly diagnosed type 2 diabetic subjects [ 78 ]. Vitamin C has also been shown to reduce anxiety levels but not stress and depression scores in diabetes [ 79 ]. Three month supplementation of vitamins C and E decreased hypertension, blood glucose while increasing superoxide dismutase and glutathione levels [ 80 ].…”

Vitamin C as an adjuvant for treating major depressive disorder and suicidal behavior, a randomized placebo-controlled clinical trial

“…There are some promising reports about the beneficial effect of vitamin C in animal models of depression. ‘Nevertheless, supplementary vitamins C did not decrease depression in type 2 diabetic patients in a randomized, single-blind, placebo-controlled trial’ [ 9 ].…”

“…The 21-item Beck Depression Rating Scale score decreased from 14.133 ± 4.37 to 3.233 ± 7.08 ( P < 0.018) [ 15 ]. Nevertheless, supplementary vitamin C (1,000 mg/day) did not decrease the depression score in type 2 diabetic patients in a randomized, single-blind, placebo-controlled trial [ 9 ].…”