Arrhythmia 
Arrhythmia is a general term for an irregular heartbeat, caused by problems in the heart's electrical system, which regulates heart rhythm.  A heartbeat can be too slow (bradycardia), too fast (tachycardia), or simply irregular.

Blood pressure
The force exerted by blood on the walls of the arteries. This pressure is greatest during the contraction of the ventricles of the heart (systolic pressure), which forces blood into the arterial system. Pressure falls to its lowest level when the heart is filling with blood (diastolic pressure).

Depression
A potentially serious mental health condition that involves the body, mind and emotions, often characterized by a profound change in mood and/or a profound loss of interest in once-pleasurable things or activities.  Depression can affect the way you eat, sleep and function; how you feel about yourself and others; and what think about the world around you.

Epithelium
A membranous cellular tissue that covers a free surface or lines a tube or cavity of a body and serves especially to enclose and protect the other parts of the body and to produce secretions and excretions.

Glucose intolerance
Increased blood glucose levels following a meal (or glucose tolerance test). The degree of glucose elevation can be severe, for example in diabetes, or relatively modest in persons with impaired glucose tolerance, a state of abnormal glucose metabolism between normal and diabetic.

Heart disease
An abnormal organic condition of the heart or of the heart and circulation.

Heart rate variability 
Beat-to-beat alterations in heart rate.

Hypertension 
A condition in adults normally described by a systolic pressure of greater than 140 mmHg or a diastolic pressure greater than 90 mmHg.  Typically, three separate abnormally high readings over a few weeks is necessary to diagnosis this condition.

Inflammation 
A local response to cellular injury that is marked by capillary dilatation, leukocytic infiltration, redness, heat, and pain and that serves as a mechanism initiating the elimination of noxious agents and of damaged tissue.

Inflammatory proteins
Proteins that promote inflammation.

Isulin resistance 
Decreased sensitivity to the action of insulin. Typically measured as the degree that glucose is cleared from the blood in response to a given amount of insulin.

Mood disorders
Used to describe the wide variety of depressive states possible because of the numerous possible symptoms and combinations of symptoms that a patient might exhibit as someone suffering from depression or anxiety.

Platelets 
A minute colorless disk-like body of mammalian blood that assists in blood clotting by adhering to other platelets and to damaged epithelium.

Protein 
Any of various naturally occurring extremely complex substances that consist of amino-acid residues joined by peptide bonds, contain the elements carbon, hydrogen, nitrogen, oxygen, usually sulfur, and occasionally other elements (as phosphorus or iron), and include many essential biological compounds (as enzymes, hormones, or antibodies).

Stress 
A state resulting from bodily or mental tension as a consequence of factors that tend to alter an existing equilibrium.

Stress hormones 
A product of living cells related to the body's reaction to stress that circulates in body fluids and produces a specific effect on the activity of cells usually remote from its point of origin.