Everyday health numbers
The figures a reader is asked to remember — caffeine, water, sleep, steps, blood pressure — and what each one is actually based on.
Everyday Nutrition
3 guides filed under this heading
- Potassium-based salt substitutes: who should ask a clinician first
Most salt substitutes swap sodium chloride for potassium chloride. For healthy kidneys it is usually unremarkable. For others it is a question for a clinician.
6 min read - How Much Caffeine Is Too Much? The FDA's 400 mg Guide
The FDA says 400 mg a day is fine for most adults — about 2–3 twelve-ounce coffees. Here's what's in your drinks, the hidden sources, and when to cut back.
4 min read - How much water should you drink? The official table, and what counts
The official numbers are Adequate Intakes measured in total water, set from survey medians. What they actually say, what counts toward them, and when they rise.
6 min read
Blood Pressure
1 guide filed under this heading
- Blood pressure numbers explained: what the categories mean and how to measure at home
The official blood pressure categories, what 120/80 and 130/80 mean, why 'normal by age' charts mislead, and how to measure at home correctly.
5 min read
Sleep and Recovery
1 guide filed under this heading
- How much sleep do adults need? Where 'eight hours' came from
The federal sleep-duration table gives adults a floor, not a target, and the familiar eight is a midpoint. How to read the row that applies to you.
5 min read
Exercise and Activity
1 guide filed under this heading
- The federal exercise guidelines count minutes, not steps. A step target is now under review.
Adults are told to get 150 to 300 minutes of moderate activity a week and two days of strength work. No federal step target exists — and HHS is taking evidence.
7 min read updated October 14, 2026
Prescription Drugs
1 guide filed under this heading
- Generic vs. brand: what has to match, and what may legally differ
An approved generic must match the brand's active ingredient, strength, dosage form and route. The pill, the fillers and the expiration date can differ.
9 min read
Medication Safety
1 guide filed under this heading
- How to Dispose of Unused or Expired Medicine Safely
Leftover medicine is a poisoning and misuse risk. Use a take-back program first; trash only as a last resort; flush only if on the FDA flush list.
3 min read updated October 23, 2026
Reference pages
Tables and lookups on the same filing, answered without reading around it
- Blood pressure categories: where a reading actually falls
Enter the two numbers and see which published category the reading lands in — normal, elevated, stage 1, stage 2 or crisis — and which number decided it.
- Sleep by age: the row that applies, and where eight sits
The CDC's nine age rows, the three panels behind them, and what eight hours means in each adult row — a floor at 18–60, a midpoint, a ceiling after 65.
- Caffeine by drink, added up against 400 mg
Typical caffeine for coffee, tea, soft drinks and energy drinks, and a running total against the FDA's 400 mg figure for most adults, kept as a range.
Other topics on Vitals
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