Blood Pressure
Systolic over diastolic—e.g. 120/80—shows force on artery walls during and between heartbeats.
MedlinePlus Definitions of Health Terms: General Health
Wellness is more than meals and workouts. When you know what metrics like blood pressure and BMI actually mean, you can read lab results, track trends, and talk with your care team with confidence.
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General health terms in one reference page
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Each entry breaks down a common measurement or body signal so you are not guessing when you see it on a chart, device, or form.
Blood pressure & heart rate
Learn systolic vs. diastolic numbers, what typical readings look like, and how heart rate fits into cardiovascular awareness.
Read on MedlinePlusBlood alcohol content
See how BAC is measured in blood samples and why medical and legal standards use the same grams-per-volume framework.
Read on MedlinePlusBody mass & temperature
BMI categories from height and weight, plus what body temperature reflects about your current level of heat regulation.
Read on MedlinePlusBlood type & Rh factor
Four major types (A, B, O, AB) and inherited Rh-positive or Rh-negative status explained without technical overload.
Read on MedlinePlusCycle & fertility signals
Cervical mucus, basal temperature, ovulation tests, menstruation, and spotting—how they connect when you track patterns.
Read on MedlinePlusBreathing & exposure
Respiratory rate, inhaler usage, UV exposure, and related everyday terms that show up in wellness apps and clinic visits.
Read on MedlinePlusTrust & authority
Built on federal health expertise
MedlinePlus is produced by the National Library of Medicine. Definitions on the General Health page draw from institutes such as the National Heart, Lung, and Blood Institute and the National Institute on Alcohol Abuse and Alcoholism—so explanations stay aligned with clinical usage.
Being healthy starts with knowing how your body works and what it needs. This glossary is a practical first step before you dive into fitness, nutrition, minerals, or vitamins content on the same platform.
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