A supplement tub or bottle has two kinds of text on it. One is marketing: the front of the pack, the big claims, the colors and the words that make you reach for it. The other is the Supplement Facts panel and the ingredient list, usually on the side or back. The second part is where the comparable facts live, and it is what we use to build our supplement comparison tables.
This guide explains how to read that panel so you can compare two products on the same terms. It does not tell you which supplement to take or whether you need one at all. That is a conversation for you and your doctor or pharmacist, especially if you are pregnant or nursing, take medication, have a medical condition or are under 18.
These statements have not been evaluated by the Food and Drug Administration. Supplements are not intended to diagnose, treat, cure, or prevent any disease.
Start with the serving size
Everything else on the panel is calculated per serving, so the serving size is the first line to read. It might be one scoop, two capsules, three capsules, five chews or one stick pack.
Two products can look alike until you notice that one lists a one-capsule serving and the other a three-capsule serving. The amount per serving might match, but you would be taking three times as many capsules from the second bottle to get there, and the bottle would run out three times faster.
Questions to ask when you read the serving size:
- How many capsules, scoops, chews or packets make one serving?
- Is the serving size the amount the brand actually suggests taking, or a fraction of it?
- For powders, is the scoop included, and does the label give a weight in grams?
Servings per container
Right below the serving size you will usually see servings per container. This is the number that turns a sticker price into a real cost.
A 90-serving tub at a higher price can work out cheaper per serving than a 30-serving tub that looks like a bargain. Always check this line before comparing prices.
Working out price per serving
Price per serving is simple arithmetic:
- Take the price you would pay for one container.
- Divide it by the servings per container.
On our comparison pages, we use the brand's one-time list price on the date we checked it, divided by the servings the brand lists. Subscription discounts, bundles and sales change the real figure, so treat our number as a starting point and redo the math at checkout.
If you are comparing products with different serving sizes, you can go one step further and work out the price per gram (for powders) or per milligram of the main ingredient. For example, two creatine products can both be "one serving" while delivering different amounts, so price per gram of creatine is the fairer comparison. Our creatine basics guide walks through that example.
Amount per serving
The middle of the panel lists each dietary ingredient and how much is in one serving, in units such as:
- g (grams) for larger amounts, like protein or creatine
- mg (milligrams), one-thousandth of a gram, for most minerals and many other ingredients
- mcg (micrograms), one-thousandth of a milligram, for some vitamins
- IU (International Units), still printed for some vitamins such as vitamin D, often alongside mcg
Read the unit as carefully as the number. 200 mg and 200 mcg are very different amounts.
Elemental amount versus compound weight
Minerals are often bound to another molecule to make a usable form. Magnesium bisglycinate, magnesium malate and magnesium L-threonate are all magnesium plus something else. Labels may show the weight of the whole compound, the weight of the mineral itself (the elemental amount), or both.
When you compare minerals, compare the elemental amount where the label gives it. On our magnesium table we show the elemental magnesium per serving the brand lists, along with the form.
% Daily Value
Many lines on the panel show a % Daily Value (%DV). This compares the amount per serving with a reference amount set for labeling. It is a labeling convention for comparing products, not a personal target, and not every ingredient has one. Ingredients without a Daily Value are usually marked with a symbol and a footnote.
A high %DV is not automatically better, and some nutrients have upper limits. Your doctor or pharmacist can tell you how a product fits with your diet and anything else you take.
Proprietary blends
Some panels group several ingredients under a blend name and give one total weight for the whole blend, without the amount of each ingredient. That is legal, but it means you can't tell how much of any single ingredient you are getting, and it makes side-by-side comparison much harder. When we can't confirm an amount from the label or the brand's page, our tables say "See site" rather than guess.
Other ingredients
Below the panel you will find other ingredients: capsule material, flavors, sweeteners, anti-caking agents, oils used to carry fat-soluble vitamins and so on. This is where you can check:
- Whether a capsule is gelatin or plant-based
- Which sweeteners are used, if any
- Whether a fish, algae, olive or other oil is used
- Colors and flavors
If you avoid particular ingredients, this list matters as much as the main panel.
Allergen statements and warnings
US labels must declare major food allergens such as milk, soy, egg, fish, shellfish, tree nuts, peanuts, wheat and sesame. Look for a "Contains" line. Whey protein contains milk; many omega-3 products contain fish; some electrolyte mixes contain coconut.
Read the warnings section too. Labels often say to consult a healthcare professional if you are pregnant, nursing or taking medication, and some products are not intended for people under 18. Those warnings are written for a reason.
Front-of-pack words to read carefully
Front panels often use words that sound precise but aren't standardized:
- "Clinically dosed" or "clinical strength" tells you what the brand believes, not what an independent body has confirmed
- "Pharmaceutical grade" is not a defined term for dietary supplements in the US
- "Clean" and "pure" have no single legal definition
- "Tested" can mean anything from a single in-house check to an independent certification program
That last point is important enough to have its own guide: third-party testing explained.
Lot numbers and dates
Look for a lot or batch number and a best-by or expiration date, usually printed on the bottom or the lid. If a brand publishes batch test results, the lot number is how you match the results to the container in your hand. It also matters if a product is ever recalled.
A simple checklist
Before you compare two supplements, write down for each one:
- Serving size (and how many capsules, scoops or chews that means)
- Servings per container
- Price for one container, and the price per serving you work out
- Amount of the main ingredient per serving, with its unit
- The form of the ingredient, where relevant (for example, which form of magnesium)
- Third-party certification, and whether you could find the product in the certifier's own listing
- Allergens and other ingredients you care about
Then take the list to your doctor or pharmacist if you have any doubt about whether the product suits you.
How Still Stride uses labels
Our supplements section lays these label facts out side by side, with each fact linked to the official product page and the date we checked it. We don't score or rank products, and we don't repeat benefit claims. Prices and formulas change, so always read the current label before you buy.
About this guide
Our supplement guides explain labels, testing programs and terms so you can ask better questions. We don’t make disease or treatment claims, we haven’t hands-on tested products, and we don’t publish invented statistics or ratings. Product facts come from official brand pages and certifier listings. How we work.