The purpose of this research study is to examine the role oxidants, substances produced in the blood that can damage blood vessel function, may play in blood vessel function in healthy individuals as well as individuals with mental health disorders (posttraumatic stress disorder (PTSD) and/or generalized anxiety disorder (GAD)).

Study #1 is made up of three sessions done on three separate days and the entire study can be completed in as little as two weeks. All testing sessions will take place at the Exercise Physiology Research Laboratory. Volunteers will be asked to participate in one initial testing session (Visit 1) lasting < 1 hour that will help make them more familiar with the study equipment and procedures, determine body measures (height, weight, body fat), determine the maximum strength of their forearm and calf, and require one blood draw. The following two testing sessions (Visits 2 and 3) with each session lasting between 2-3 hours that will involve multiple tests designed to determine the health of their blood vessels. For Visit #2 they will be randomly given either antioxidant pills or placebo pills to determine the effect of oxidants on blood vessel health. For Visit #3, they will be given whatever set of pills (antioxidant or placebo) that they did not receive during Visit #2.

Inclusion Criteria:

• apparently healthy and free of overt cardiovascular, pulmonary, or metabolic disease
• for PTSD group, a score of ≥ 33 on PCL-5 checklist
• for GAD group, a score of ≥ 10 on the GAD-7 self-report scale and < 33 on the PCL-5 checklist
• for Healthy Control group, a score of ≤ 10 on the GAD-7 self-report scale and < 33 on the PCL-5 checklist

Exclusion Criteria:

• taking medications that could influence cardiovascular function
• current smokers who have recently quit smoking
• illicit drug use or excessive alcohol consumption
• pregnant women
• significant calorie restriction or vitamin/mineral deficiencies
• limited English proficiency