You’ve set your New Year’s resolutions. So far, you’ve been good, but as the month wears on, you may look to some external help to motivate you before you hit the gym. Widow Cassondra Reynolds warns you may not want to drink that pre-workout energy drink.

Her husband John died at 41 after he consumed an energy drink and went into cardiac arrest. Just a month prior John was deemed in good health. John’s death was attributed to cardiac arrest with the drink as the likely culprit. Doctors told Reynolds just one or two energy drinks a day were enough to disrupt someone’s natural heart rhythms and cause cardiac problems.

Kevin Carley and his wife Daphne took to social media after his near-death experience involving similar pre-workout supplement drinks. Kevin ended up in a coma after he consumed a drink one morning then collapsed shortly after at the local YMCA. Thankfully, Kevin survived his cardiac event.

Doctors warn that the dosing percentages of these supplements and their chemical composition need more regulation by the government. Some products can deliver up the same amount of caffeine as 100 cups of coffee in just one dose. Consider this before you buy that next silver or black can of ready-made energy: you could be taking your life into your hands.