Column · Absorbency & Heavy flow
Edition 1
September 2026
The Reading Room
Free to read
Canada
Free to read · Canada
Edition 1 · Published by Periodica ·
The Reading Room · Edition 1 ·
Period School
“Super” on a period pad and “Super” on a tampon are not the same thing.
At a glance
Who it’s for: Anyone who has been puzzled by the absorbency words on a box.
Reading time: About 9 min
On this page:
- One word. Two very different meanings.
- 01 · The word on the box
- 02 · What does “Super” actually mean?
- 03 · So why doesn’t “Super” mean the same thing everywhere?
- 04 · The strange part: what are we testing with?
- Translating the labels, format by format
- When heavy is worth a conversation
- What this is not
In three points:
- “Super” on a tampon has a standard meaning in Canada. “Super” on a period pad does not.
- For period pads, period underwear, cups and discs, there is no Canadian absorbency standard and no required standard test.
- If your periods are very heavy, very painful or have changed, or if something here worries you, that is a conversation for a healthcare provider.
General information, not medical advice. For anything about your own health, talk to a healthcare provider. Where to get help
- The Editor’s letterCome in. The library is open.
- Wait. What? · The labWhat labs use to test a tampon
- The rulesWhat’s regulated in Canada
Editor’s Note
Dear reader,
I chose absorbency for the first Edition because it was the first label that confused me. I had bought “super” for years without knowing what the word promised, or who had decided. So this Column starts with the box, not the body: what Canada regulates, what it does not, and what one laboratory measured with real blood. Read at your own pace. If a label has ever puzzled you, tell the Editor; the questions become next month’s reading.
— The Editor
- Light
- Regular
- Super
- Heavy
- Overnight
- Ultra
They are supposed to help us choose a product that matches our flow.
Does Super mean the same for a period pad or a tampon? And does it mean the same across different brands? This is a lesson in absorbency, measurement and what “heavy” actually means.
Welcome to Period School.
One word. Two very different meanings.
- TamponStandardized
- Period padBrand-defined
- Period underwearBrand-defined
- CupCapacity
- DiscCapacity
01
The word on the box
Pick up a box of tampons in Canada and you’ll find something unusual: the absorbency language has a standard behind it.
Health Canada requires tampons sold in Canada to use a standardized absorbency system. So a Super tampon has to fit the same regulated range, no matter which brand made it.
That is not true for period pads, period underwear, cups or discs.
Think of it like shoe sizes
If two shoes both say “size 8,” you expect the number to refer to the same sizing system. With period products, “Super” does not always work that way.
02
What does “Super” actually mean?
Here’s the technical part: Canada measures tampon absorbency in grams of test fluid.
Most of us do not walk around thinking in grams. So let’s translate the scale into something you already know: measuring spoons.
The categories are Health Canada’s. The spoons are our approximation: 1 teaspoon is 5 mL, 1 tablespoon is 15 mL, and a gram of test fluid takes up about a millilitre.
The useful bit
“Super” is not a score. It is simply one of Canada’s absorbency categories: more than 9 and less than 12 grams of test fluid.
03
So why doesn’t “Super” mean the same thing everywhere?
Because Health Canada sets absorbency labels only for tampons. For period pads, period underwear, cups and discs, there is no Canadian absorbency standard and no required standard test: each brand decides how to test its products, and is responsible for being able to back what the package says.
What’s regulated in Canada
| Product | How Canada regulates it | Standard absorbency test? |
|---|---|---|
| Period pads & liners | General consumer-product safety law | No |
| Tampons | Medical device; must be licensed by Health Canada | Yes: standard terms and ranges on the label |
| Cups | Medical device; must be licensed by Health Canada | No |
| Discs | Medical device; must be licensed by Health Canada | No |
| Period underwear | Consumer-product safety law and textile labelling law | No |
| Reusable period pads | Consumer-product safety law and textile labelling law | No |
Says who? Health Canada, Medical Devices Regulations, Medical Devices Active Licence Listing and Guidance for the Labelling of Medical Devices, Appendix 2; Canada Consumer Product Safety Act; Textile Labelling Act.
“Super” on a tampon has a standard meaning in Canada. “Super” on a period pad does not.
| On the package | What the word means |
|---|---|
| Tampon · Super | A standardized Canadian absorbency category. |
| Period pad · Super | A description chosen by the brand. |
| Period underwear · “4 tampons” | A brand’s capacity claim. |
| Cup · 30 mL | A stated capacity. |
| Disc · 50 mL | A stated capacity. |
The numbers are examples of how packages are labelled, not measurements.
04
The strange part: what are we testing with?
If we’re trying to find out how much a period product can absorb, you might assume researchers use menstrual blood.
Reasonable assumption. But historically, saline has commonly been used in menstrual-product testing.
Finally, in 2023, researchers at Oregon Health & Science University tested 21 menstrual products in a laboratory.
They tested period pads, tampons, period underwear, cups and discs using expired human packed red blood cells.
Blood and saline move differently, and period blood also carries cells, proteins and tissue, so a saline result does not translate directly to real use.
The study covered five formats: period underwear, period pads, tampons, cups and discs. On average, discs held the most, 61 mL. Period underwear held the least, about 2 mL. Tampons, heavy or ultra period pads and cups held similar amounts, roughly 20 to 50 mL. The single largest capacity was a disc, at 80 mL.
One study, 21 products, measured with red blood cells.
Two cautions. This is one study of 21 products, and the products were saturated to their maximum in a laboratory, which is not how anyone wears them. The numbers describe capacity, not comfort, and not what a product holds before it leaks.
A note about the numbers
are three different things.
Translating the labels, format by format
-
Tampons
“Light”, “regular”, “super”, “super plus” and “ultra” are the regulated ranges above, the same whichever brand you hold.
-
Period pads and liners
“Light”, “regular”, “heavy” and “overnight” are the brand’s words.
-
Period underwear
Labels often speak in “tampons’ worth”. One Canadian brand’s label reads “Absorbs 4-8 regular tampons”. No public test standard sits behind that unit. In the study, underwear held the least of the five formats.
-
Cups and discs
These collect rather than absorb, so their honest unit is capacity in millilitres. Wear time is set by the manufacturer’s instructions; another Column in this Edition covers it.
When heavy is worth a conversation
“Heavy” on a package is a brand’s word. “Heavy” for a period has a clinical definition: 80 mL or more in one cycle. The SOGC lists practical signs, in its words:
- “Bleeding that soaks through one or more tampons or pads every hour for several hours in a row.”
- “Needing to wear more than one pad at a time to control menstrual flow.”
- “Needing to change pads or tampons during the night.”
- “Menstrual flow with blood clots that are as big as a quarter or larger.”
- “Bleeding that lasts more than 7 days.”
The SOGC adds: “your perception of your bleeding is more important than the actual amount of blood loss.”
A counting aid, not a test
For anyone who wants to count, CeMCOR offers a counting aid, not a test: a fully soaked normal-sized period pad or tampon holds roughly 5 mL, a maxi or super roughly 10 mL, so 16 soaked normal-sized products in one period is about 80 mL.
If your periods are very heavy, very painful or have changed, or if something here worries you, that is a conversation for a healthcare provider, not for a Column.
This is where the Editor stops and a healthcare provider begins.
Where to go from here
- Your family doctor, nurse practitioner or a walk-in clinicFor a conversation about heavy periods.
- 8-1-1, your provincial nurse lineAvailable in several provinces.
- SOGC, yourperiod.caCanada’s gynaecologists’ guide to periods, including heavy bleeding.
What this is not
This Column compared labels and one study’s measurements. It did not compare brands, and it has no test of its own. It did not tell you which format to choose. Two people with the same flow choose differently, and both are right.
Next in the Reading Room: “Menstrual cups, explained gently.”
Drafted and checked against its sources with our proud team of AI assistants; read and signed by the Editor.
This Column is general information, compiled by the Editor from the sources listed below. It is not medical advice, and the Editor is not a healthcare provider. For anything about your own health, talk to a healthcare provider.
No rush. We like reading slowly, one short piece at a time. The articles will wait for you.
Sources the Editor read (12)
- Health Canada, “Menstrual tampons” (page modified 2015-02-12). canada.ca
- Health Canada, Guidance for the Labelling of Medical Devices, Appendices (Appendix 2, Labelling for Menstrual Tampons). canada.ca
- DeLoughery E, Colwill AC, Edelman A, Samuelson Bannow B. “Red blood cell capacity of modern menstrual products: considerations for assessing heavy menstrual bleeding.” BMJ Sexual & Reproductive Health 2024;50(1):21–26. doi.org/10.1136/bmjsrh-2023-201895
- Thompson J. “No One Studied Menstrual Product Absorbency Realistically Until Now.” Scientific American, 2023-08-22. scientificamerican.com
- van Eijk AM et al. “Menstrual cup use, leakage, acceptability, safety, and availability: a systematic review and meta-analysis.” Lancet Public Health 2019;4:e376–e393. doi.org/10.1016/S2468-2667(19)30111-2
- Society of Obstetricians and Gynaecologists of Canada, yourperiod.ca, “Heavy menstrual bleeding”. yourperiod.ca
- CeMCOR, University of British Columbia, “Very Heavy Menstrual Flow” (updated 2025). cemcor.ubc.ca
- Diva International Inc., “The DivaCup User Guide” (PDF, undated). PDF
- nixit, “How to use”. nixit.ca
- Aisle, product page “Adjustable Absorbency Period Underwear with BOOSTER”. periodaisle.com
- United States, 21 CFR § 801.430, “User labeling for menstrual tampons” (current text). law.cornell.edu
- Vostral S. “Toxic shock syndrome, tampons and laboratory standard-setting.” CMAJ 2017;189(20):E726–E728. pmc.ncbi.nlm.nih.gov
Manufacturer and brand documents are cited as the source of a quotation or an example of labelling; the citation is not an endorsement.
Date due for review
| Written by | The Editor |
| Last checked | 26 Sep 2026 |
| Next check | Mar 2027 |
Find more like this
- Shelf
- Flow, Fit & Absorbency › Absorbency & labels
- Formats
- Period pads & liners · Tampons · Cups · Discs · Period underwear
- Needs
- Heavy flow · Overnight
- Collections
- Heavy flow · Health concerns
Read next: Period products, explained. · Glossary: Absorbency
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