Synthetic and Natural Caffeine on Hemodynamic Parameters in Young, Healthy Volunteers

The purpose of this study determine the difference in hemodynamic effects of synthetic and natural caffeine consumption in healthy individuals through blood pressure (central and peripheral) assessment. Participants will randomly be assigned to consume either one 8oz cup of coffee containing 400mg of caffeine (increased caffeine using concentrated coffee) or one 8oz cup of coffee-flavored drink with approximately 400mg synthetic caffeine from capsules dissolved in it.

The purpose of this study is to assess the difference in effects of consuming synthetic versus natural caffeine on hemodynamic parameters in healthy subjects. This study will determine the difference in hemodynamic effects of synthetic and natural caffeine consumption in healthy individuals through blood pressure (central and peripheral) assessment. The participants in this study are healthy adults who will be introduced to a risk that may be more than they would encounter through their normal daily activities. This study seeks to add to the literature by evaluating the difference in impact of synthetic compared to natural caffeine on central blood pressure.

This protocol has the following aims:

1. Investigators hypothesize there will be a (baseline adjusted \[ΔBP\]) difference in BP (peripheral and central) between the natural and synthetic caffeine arms in healthy volunteers post consumption.
2. Investigators hypothesize there will be (baseline adjusted \[ΔCO\]) no difference in CO between the natural and synthetic caffeine arms in healthy volunteers post consumption.
3. Investigators hypothesize there will be (baseline adjusted \[ΔSVR\]) no difference in SVR between the natural and synthetic caffeine arms in healthy volunteers hours post consumption.

Eligibility Criteria:
Inclusion Criteria:

* Healthy males and females
* Active duty military service members
* DoD beneficiaries
* Participants must be willing to refrain from caffeine use 72 hours prior to study days one and five

Exclusion Criteria:

* Cardiovascular risk factors: Heart rhythm other than normal sinus, history of atrial or ventricular arrhythmia, family history of premature sudden cardiac death before the age of 60, left ventricular hypertrophy, acute myocardial ischemia, atherosclerosis, hypertension, and palpitations. This will be determined through the questionnaire responses of the participant and thorough chart review.
* Blood pressure at initial screening appointment or at baseline on study Day One greater than 130/80 and if 130-139/80-89, FRS risk greater than 10%.
* Presence of any known medical condition, confirmed through participant interview up to the discretion of the research team. Examples of these are:
* Hypertension
* Thyroid disease
* Type 1 or 2 Diabetes Mellitus
* Recurrent headaches
* Any psychiatric condition or neurological disorder including seizures
* History of alcohol or drug abuse in the previous five years
* Ever been diagnosed or told they have or had renal or hepatic dysfunction
* Tobacco use
* Concurrent use of any medication taken in an amount greater than twice a week, to include herbal products or supplements, not to include hormonal contraceptives. If less than or equal to two days per week, the investigator will determine if the subject is to be included or excluded based on the available literature for that medication.
* Pregnant or lactating females will be excluded from participation with urine dipstick tests used to rule out pregnancy (pregnancy test performed before each treatment session, days one, five)
* All non-English speaking/writing subjects and those that do not understand the study or consent process will be excluded from the study due to unavailability of medical qualified translator at all times during the study.
* If the subject refuses to sign the informed consent document or HIPAA Authorization, they will be excluded as well.
* Allergy to any substance in the study design.
* Any other medical reason that at the discretion of the investigators would pose a risk to the health of the subject.