How to Read a Supplement Label Without Getting Fooled
The front of the bottle is marketing. The Supplement Facts panel is the closest thing to accountability the category has — and most of what you need to know is either in it, or conspicuously absent from it.
Read First
Facts panel
Biggest Red Flag
Proprietary blend
For Probiotics
CFU per strain
For Botanicals
Standardisation %
The Parts of a Label That Matter
Ignore the front panel entirely on a first pass. Health claims, imagery and product naming are marketing decisions, and none of them are verified by anyone before the product goes on sale. Everything useful is on the back.
| Element | What it tells you | What to watch for |
|---|---|---|
| Serving size | How much you must take to get the stated amounts | A '2 capsule' serving means a 60-count bottle is 30 days, not 60 |
| Amount per serving | The actual dose of each active | Compare against the dose used in the research cited |
| % Daily Value | Relevance for vitamins and minerals | Blank for most botanicals — no DV has been established |
| Other ingredients | Fillers, capsule material, allergens | Long lists are not automatically bad, but should be short for simple products |
| Structure/function claim + dagger | A claim the company has not had to prove | The dagger is a signal to read sceptically |
| Lot number and expiry | Traceability and shelf life | Absence is a genuine quality concern |
Proprietary Blends: The Single Biggest Red Flag
A proprietary blend lists several ingredients together under one combined weight. The label tells you the blend is 500 mg and names five ingredients, but not how much of each. Companies justify this as protecting a formula from competitors.
What it actually enables
It allows a company to include an expensive, well-researched ingredient in a trivial amount — enough to name it on the label, not enough to do anything — while filling the rest of the blend with something cheap. This is common enough to have a name: fairy dusting. If you cannot see individual amounts, you cannot rule it out.
There is a partial version of this too. In our supplement reviews, CoreAge Rx lists its probiotic blend as 36 mg total across three strains without breaking out individual amounts — so while the fibers are individually dosed, the strain quantities are not knowable. Lemme, by contrast, publishes every active separately with its standardisation percentage. That difference is visible on the label and tells you something.
Probiotics: Demand CFU Counts
Probiotic potency is measured in colony-forming units, not milligrams. A weight tells you the mass of powder; CFU tells you how many live organisms are in it. These are not interchangeable, and a product listing only milligrams cannot be compared with research doses or with competitors.
- •Look for CFU per strain, not just a total across the blend
- •Check whether CFU is stated at time of manufacture or at end of shelf life — the latter is a stronger commitment
- •Look for the full strain designation where possible, since effects are strain-specific rather than species-wide
- •Check storage requirements; a live-culture product that needs no refrigeration is worth a question
- •Cold-chain shipping is a good sign — it means the company is treating viability as a real problem
A pattern worth noticing
Of the two probiotic products in our supplement coverage, neither publishes CFU counts on its product page. That is not unusual in this category, and it is the most common disclosure gap we found. It is entirely reasonable to email a company and ask.
Botanicals: Standardisation Is the Number That Matters
For a plant extract, the milligram amount alone is nearly meaningless without knowing its concentration of active compounds. 400 mg of a weak extract and 400 mg of a concentrated one are entirely different products.
Standardisation solves this. Lemme's label is the clearest example we found: 400 mg Morosil standardised to 0.8% anthocyanins, 200 mg Eriomin standardised to 70% eriocitrin, 176.5 mg Supresa standardised to 0.3% safranal. Those percentages let you check whether the dose matches what the ingredient supplier studied — which is the entire point.
Branded ingredients (the ® and ™ names) are a mixed signal. They generally indicate a specific extract with its own research and consistent manufacturing, which is good. But that research is usually supplier-funded, and the branding itself is a marketing asset. Treat it as a reason to look up the research, not as a substitute for doing so.
Third-Party Testing: What the Seals Mean
Because the FDA does not review supplements before sale, independent verification is the main quality signal available. It is voluntary, which is exactly why its presence is meaningful.
| Signal | What it verifies | Strength |
|---|---|---|
| NSF Certified for Sport | Contents match label; screened for banned substances | Strong |
| USP Verified | Identity, potency, purity, manufacturing quality | Strong |
| Informed Choice / Informed Sport | Batch testing for contaminants and banned substances | Strong |
| cGMP-certified facility | Manufacturing process standards | Moderate — process, not product |
| 'Third-party tested' with no named body | Something was tested by someone | Weak — ask who and for what |
| No testing claim at all | Nothing verified independently | None |
Note the distinction between cGMP and product certification. cGMP says the facility follows manufacturing standards; it does not confirm that a specific bottle contains what the label says. Both CoreAge Rx and many competitors cite cGMP manufacturing and unnamed third-party testing — better than nothing, weaker than a named certification.
A Practical Checklist
Turn the bottle around before reading the front
Start with the Supplement Facts panel. Form your view from the numbers, then read the marketing and see whether it matches.
Check the serving size against the container count
Work out the real daily cost. A product at $89.99 for 45 servings taken four capsules daily is not a month's supply, whatever the front says.
Find every active's individual amount
If any active sits inside a proprietary blend, you cannot evaluate the product. That alone is a reasonable basis for walking away.
Compare doses to the cited research
Look up one study behind the headline ingredient and check the dose used. Mismatches are common and rarely flagged.
Look for a named third-party certification
NSF, USP or Informed Choice. 'Third-party tested' without a named body is a claim, not a verification.
Read the warnings and the refund policy
The warnings tell you who the company thinks should not take it. The refund policy tells you how confident it is. Both are more informative than the claims.
Frequently Asked Questions
What is a proprietary blend and why is it a problem?
It lists several ingredients under one combined weight without individual amounts. That allows a company to include a well-researched ingredient in a token quantity — enough to name it, not enough to matter — while the rest of the blend is cheap filler. If you cannot see individual doses, you cannot evaluate the product.
What does “standardised to 70% eriocitrin” mean?
It means the extract has been processed so that 70% of it is the named marker compound. This matters because plant extracts vary enormously in potency — without a standardisation percentage, a milligram amount tells you very little about how much active compound you are getting.
Why do probiotics need CFU counts?
Colony-forming units measure how many live organisms are present, which is what determines potency. A weight in milligrams measures powder mass, not viability. Without CFU you cannot compare products or check a dose against research.
Is a cGMP-certified facility the same as third-party testing?
No. cGMP relates to manufacturing process standards at the facility. It does not verify that any specific batch contains what the label claims. Product-level certification from NSF, USP or Informed Choice is the stronger signal.
What does the dagger symbol next to a claim mean?
It points to the FDA disclaimer stating the claim has not been evaluated and the product is not intended to diagnose, treat, cure or prevent disease. It marks a structure/function claim the company has not had to prove.
Should I avoid products with fillers like magnesium stearate?
Not necessarily. Magnesium stearate, silica and microcrystalline cellulose are common flow and bulking agents used in tiny quantities, and concerns about them are largely overstated online. A short excipient list is preferable, but their presence is not a red flag by itself.
What's the single most useful thing on a label?
The individual amount of each active ingredient. Everything else — claims, branding, certifications — is secondary to whether the product contains a meaningful dose of what it is selling itself on.
Medical disclaimer: This article is for general information only and is not medical advice. Dietary supplements are not evaluated by the FDA for safety or effectiveness before they are sold. Label requirements and certification programmes change over time. Talk to a pharmacist or licensed healthcare professional about specific products, particularly if you take medication or have a medical condition.
Disclosure: This article may contain affiliate links. If you sign up through our links, we may receive a commission at no additional cost to you. This does not influence our editorial recommendations.
Put It Into Practice
See how the main GLP-1 supplements compare on exactly these criteria — doses, potency measures and disclosure.