The purpose of the present study is to explore the effects of a dietary nitrate supplement (i.e., beetroot juice) on nitric oxide levels, immunity, mood, and cardiovascular activity during and following final exam stress in healthy individuals.

Research has demonstrated that during times of high stress (i.e., during final exam period), there is a decrease in fraction of exhaled nitric oxide (FeNO) in healthy undergraduate students. Additionally, a separate line of research has demonstrated periods of high stress impact immunity and the cardiovascular system. Nitric oxide may have a benefit in improving the physiological and psychological consequences of stress.

The present research aims to explore the impact of a dietary supplement (beetroot juice drink) on immunity, nitric oxide levels, cardiovascular activity, and mood during and following final exam stress. In this study, investigators monitor changes in cold symptoms, IL-8, blood pressure, airway nitric oxide, and mood in students during the time of final exams and a comparable time of low stress during the term. There are three laboratory assessment visits, as well as a brief questionnaire on a separate day. During the final exam period, half of the participants are randomly assigned to the experimental group provided with a dietary supplement (beetroot juice drink) of which they are asked to take two doses every day (one in the morning and one in the evening) for seven days. The other half of the participants are randomly assigned to the placebo control group provided with a placebo supplement (placebo drink) of which they are asked to take two doses every day (one in the morning and one in the evening for seven days). For the final exam period, the first of the two sessions takes place early in the examination period (first half), and the second assessment takes place in the later exam period (second half). The online questionnaire assessing symptoms is measured 3 days after the final examination period.

Inclusion Criteria:

• Currently enrolled at Baylor University or Southern Methodist University

Exclusion Criteria:

• Current smoker
• Clinically significant asthma, COPD, Emphysema, heart disease, cerebrovascular disease, thyroid dysfunction, out of control diabetes
• Pregnancy, diagnosis of schizophrenia, psychosis, mood disorder, psychosis, drug or alcohol dependance

The lead researcher, data collectors, and participants were blinded to the conditions. The distribution of the supplements for each condition was performed by a member of the staff that was not involved with the study.