Caffeine in supplements: where it comes from and how to add it up
Caffeine rarely sits in one place in a formula. Some arrives as pure caffeine, some through guarana or green coffee. How to add up the total, and what to compare it against.
August 31, 2026
If a label says “caffeine 180 mg” and, further down, “guarana extract 16 mg, 10% caffeine”, the total is not 180 mg. Here is how it adds up.
The two sources
Caffeine in supplements arrives in two ways:
- as pure caffeine — anhydrous caffeine or caffeine citrate, declared directly in milligrams
- through a plant extract — guarana, green coffee, green tea, yerba mate — where caffeine is a fraction of the extract
In the second case the amount depends on the extract's standardisation, not on its weight.
The arithmetic
A guarana extract standardised to 10% caffeine, at 16 mg of extract, gives:
- 16 mg × 10% = 1.6 mg of caffeine
Add that to the declared pure caffeine and you have the total for the daily intake. For a formula with 180 mg of pure caffeine plus 16 mg of guarana at 10%, the total is 181.6 mg.
The extract figures are usually small. So when a label shows a large caffeine number, it almost always comes from the pure caffeine rather than the botanical part — however it is presented.
What to compare it against
The European Food Safety Authority (EFSA) reference figures for adults without specific health conditions are:
- up to 400 mg per day from all sources
- up to 200 mg in a single dose
For scale: an espresso holds roughly 70–80 mg, a cup of filter coffee about 90–120 mg, a 250 ml can of energy drink about 80 mg. These add to whatever comes from a supplement.
Pregnancy and children
EFSA gives up to 200 mg per day during pregnancy and breastfeeding. Caffeinated food supplements are not intended for children or adolescents.
What our labels say
Where a formula contains caffeine, the amount is printed in milligrams for the maximum daily intake, not merely as “contains caffeine”. If you take other sources during the day, that is the figure to add to them.
