A WARNING has been issued to those who use pre-workout supplements in Barnsley.
Council officers took samples of supplements, which claimed to improve performance and burn fat, from gyms around the borough.
Analytical testing of the products found one of the supplements, Muscle Junkie Psycho Pre-Workout, to contain DMAA, a stimulant for which safe levels for human consumption have not been established.
Adverse reactions to the substance have been reported around the world and products containing DMAA have been withdrawn across the European Union.
DMAA has been linked with high blood pressure, nausea, cerebral haemorrhage, strokes and even death.
Coun Roy Miller, cabinet spokesperson for place, said: "Residents who think they may have consumed any substances containing DMAA are advised to contact their GP.
"Officers will carry out further testing on similar products in the coming months to ensure that the products on the market are safe."