Supplement guides
Supplement guides, page 7
Plain-English guides on labels, doses, real prices, free trials and refunds. Written to help you check a product, not to sell you one.
Why potassium supplement labels stop at 99 mg
Potassium pills stop at 99 mg by habit, not by a supplement law. Learn where it comes from and who needs a doctor first.
DosesPre-workout caffeine: how much per serving should you expect?
What labs found in pre-workout caffeine, what FDA says about 400 mg a day, and how blends and plant sources hide the real amount.
IngredientsPrebiotic fiber supplements: how many grams of inulin or psyllium?
Studies of psyllium and inulin use grams a day. Here is how to compare that with the fiber amounts (or blends) on a gut health label.
LabelsProbiotic labels: what CFU, strain names and expiry should tell you
Strain codes, CFU at manufacture vs expiry, and what a 182-product lab study found: how to read a probiotic label before you buy.
LabelsProtein powder labels: amino spiking and real protein
How label protein is calculated, what two lab studies of protein powders found, and how to check protein per scoop before you buy.
SafetyRed yeast rice supplements: monacolin K, citrinin and FDA warnings
Monacolin K amounts varied more than 60-fold across 26 brands, some products carried citrinin, and the FDA has warned about lovastatin. What to check.
EvidenceSaw palmetto for the prostate: what the evidence shows
What the CAMUS trial and the 2023 Cochrane review found on saw palmetto for BPH symptoms, the doses studied, and how to read a prostate supplement label.
Red flagsSecret ancient remedy claims on supplement sales pages: what to check
Origin stories, 'doctors hate this' hooks and invented terms: a ten-minute way to test a secret ancient remedy pitch, and what the FTC says.
LabelsServing size tricks: how capsules per serving change price and dose
One capsule or four per serving changes how long a bottle lasts, its real price and the dose. See how to compare two labels fairly.
PricingShipping and handling fees: what a supplement really costs per month
How shipping and handling change the true monthly cost of a supplement, with worked examples, refund pitfalls and a checklist.
Guides are general information, not medical advice. Read how we review and our medical disclaimer.