Pre-workout is a food supplement, usually a powder drunk before exercise, most often built around caffeine with beta-alanine, creatine and citrulline or arginine. In Great Britain it is sold as food, not medicine, so its label must carry the GOV.UK caffeine warning where the caffeine thresholds are met, and may make only the health claims the national register authorises.
This is an evergreen explainer. This desk read GOV.UK’s food labelling guidance (last updated 20 September 2022), the claims register page and its 19 May 2026 spreadsheet on 18 October 2026.
What is pre-workout allowed to claim on a GB label?
| Ingredient | What the register’s health claims sheet records |
|---|---|
| Caffeine | Every row naming caffeine Non-authorised, including “Improves physical performance” |
| Beta-alanine | Every row Non-authorised, including reduced muscle fatigue |
| Citrulline-malate | Both rows Non-authorised; no row names L-citrulline |
| Arginine | Every row read Non-authorised, including normal blood circulation |
| Creatine | Authorised: performance in successive bursts of short-term, high-intensity exercise, at 3 g a day |
Non-authorised is the register’s word for a claim, not a ban on the ingredient. The creatine claim is tied to a 3 g daily intake, as this site’s creatine explainer and creatine dose post set out.
What caffeine warning must pre-workout carry?
GOV.UK says drinks over 150 milligrams of caffeine per litre, including dried drinks once reconstituted, must read “High caffeine content. Not recommended for children or pregnant or breast-feeding women”. Other foods with caffeine added for a physiological purpose must say “Contains caffeine. Not recommended for children or pregnant women”. Which applies depends on the product; either shares the name’s field of vision, mg per 100 g or 100 ml bracketed.
Frequently asked questions
Is pre-workout just caffeine?
Caffeine is usually the centre of it, but many formulas add beta-alanine, creatine, citrulline or arginine. Of these, only creatine has an authorised exercise claim in the GB register, at 3 g a day. The others cannot carry the performance claims the register has refused.
Is pre-workout bad for you?
None of the documents read rules on pre-workout safety. Where the caffeine thresholds are met, the labelling guidance requires a warning that the product is not recommended for children or pregnant women. Anyone sensitive to caffeine, pregnant or on medication should ask a GP or pharmacist first.
Is it OK to take pre-workout every day?
None of the documents read sets a daily ceiling for pre-workout as a category. The label is the place to look, since a caffeine warning must carry the caffeine content per 100 g or 100 ml in brackets. A GP or pharmacist can advise an individual.
Pre-workout is a food, and this piece is about label wording only. Nothing here is medical advice; a clear caffeine figure and only register-listed claims are what to look for.