Matching Items (2)
Filtering by

Clear all filters

149530-Thumbnail Image.png
Description
Among its many roles in the body, ascorbic acid functions as a cofactor in carnitine and catecholamine synthesis, metabolites involved in fat oxidation and mood regulation, respectively. Given that fat oxidation and mood affect one's feelings of vigor, I hypothesized that those with lower levels of plasma ascorbic acid

Among its many roles in the body, ascorbic acid functions as a cofactor in carnitine and catecholamine synthesis, metabolites involved in fat oxidation and mood regulation, respectively. Given that fat oxidation and mood affect one's feelings of vigor, I hypothesized that those with lower levels of plasma ascorbic acid would be less likely to exercise at high levels than individuals with adequate or high levels of vitamin C. To test this, I conducted a double-blind, placebo-controlled intervention. A group of healthy, non-smoking males between the ages of 18 and 40 were put on a vitamin C-restricted diet for two weeks and then randomized to a control group that received placebo capsules for six weeks or an intervention group that received 500 mg of vitamin C daily for six weeks. The men were restricted from eating foods high in vitamin C, instructed to wear a pedometer daily and to record their step counts, and to take a pill daily (either the placebo or vitamin C supplement). Unexpectedly, the subjects receiving the intervention had lower step counts than the control group; the control group, rather than the vitamin C group, significantly (p=0.017) increased their steps at week 8 compared to week 2. However, I also estimated daily Metabolic Equivalent Tasks (METs), and subjects receiving the placebo had lower MET outputs than subjects receiving vitamin C at the end of the trial, in spite of having higher step counts. This means the intensity of their activity was higher, based on METs expenditure. Additionally, depression scores (POMS-D) as measured by the Profile of Mood States (POMS) questionnaire were significantly higher (p=0.041) among subjects receiving the placebo at the end of the study. These latter results are consistent with my expectations that subjects with higher levels of plasma vitamin C would have improved mood and higher energy output than subjects with low levels of vitamin C.
ContributorsNetland, Heidi (Author) / Johnston, Carol S (Thesis advisor) / Swan, Pamela D (Committee member) / Hampl, Jeffery S (Committee member) / Arizona State University (Publisher)
Created2011
158012-Thumbnail Image.png
Description
Oral contraceptives are one of the most frequently used forms of birth control among young women. However, research has shown that this type of medication can contribute to negative changes in mood and diminished vitamin status. In particular, women taking oral contraceptives are at an increased risk of vitamin B6

Oral contraceptives are one of the most frequently used forms of birth control among young women. However, research has shown that this type of medication can contribute to negative changes in mood and diminished vitamin status. In particular, women taking oral contraceptives are at an increased risk of vitamin B6 deficiency due to changes in enzyme activity with estrogen intake. Depressed mood is one of the known symptoms of vitamin B6 deficiency as this vitamin acts as an essential cofactor in converting tryptophan to the neurotransmitter, serotonin. Lack of adequate levels of vitamin B6 therefore contribute to decreased production of serotonin and subsequent changes in mood, including symptoms of depression. With vitamin B6 being the most common nutrient deficiency, and the ever increasing prevalence of depression in the United States, especially among young adults, it is crucial that researchers investigate ways to mitigate both of these undesirable side effects. Current research on the topic fails to directly connect supplementation of vitamin B6 to positive changes in mood in oral contraceptive users.

This 12-week long double-blinded, placebo-controlled crossover trial examined the effects of daily supplementation of vitamin B6 as 100 mg of pyridoxine hydrochloride, on mood states in 8 healthy college women (18-25 y) that use combined oral contraceptives. Vitamin status was assessed via plasma pyridoxal 5’-phosphate (PLP). Plasma PLP levels significantly increased by >193% (p=0.003) with daily supplementation of 100 mg B6 over a four week period. Mood changes with supplementation were assessed using the Profile of Mood States (POMS). Although a small improvement in the POMS depression sub score was observed after 4 weeks of vitamin B6 supplementation (14.7%), the changes were insignificant (p>0.05). Furthermore, total mood disturbance scores did not significantly change with either the placebo or supplement periods. While mood states were not improved, a significant decrease in the presence of depressive symptoms as measured by the Beck Depression Inventory was observed after vitamin B6 supplementation, compared to placebo (p=0.047). The results of this study necessitate further investigation into the use of B6 supplementation as a means of reducing negative mood changes in oral contraceptive users.
ContributorsCurtin, Anne Clare (Author) / Johnston, Carol S (Thesis advisor) / Whisner, Corrie M (Committee member) / Grant, Shauna C (Committee member) / Arizona State University (Publisher)
Created2020