The sudden passing of Katie Donnell, a Florida fitness enthusiast, has reignited concerns about the potential dangers of energy drinks.
The 28-year-old “workout queen”, who was dedicated to maintaining a fit and active lifestyle, suffered a fatal
heart attack—one that her family believes may have been triggered by her regular consumption of high-caffeine energy drinks.
For many, especially athletes and gym-goers, these drinks have become a popular quick fix to fight fatigue and push through intense workouts.
But with Donnell’s tragic death, it’s worth asking—could energy drinks be putting your heart at risk?
Here’s what we know.
What happened to Katie Donnell?
Katie Donnell, a Florida teacher, was known for her dedication to fitness and healthy living.
Despite her commitment to clean eating and regular workouts, her mother, 63-year-old Lori Barranon, said her daughter had one major vice—energy drinks.
“She was a workout queen, she ate real clean, she ate organic food, she was the epitome of health other than [having energy drinks],” Barranon told The Sun.
Katie reportedly drank at least three cans of energy drinks daily and also took energy-boosting supplements to sustain her twice-a-day workout routine.
“One of her friends said she’d hardly see Katie without an energy drink in her hands,” her mother said. “When I cleaned out her car after she passed, it was full of cans—at least three or four in there.”
On an August evening in 2021, while out with friends, Katie collapsed suddenly. Her friends initially suspected a stroke and immediately called for an ambulance.
But by the time medical help arrived, it was too late.
“She was without oxygen for too long, and it caused brain damage,” Barranon said. “They worked on her for three hours, and she never woke up.”
Katie remained in a medically induced coma for 10 days, but her condition only worsened. Eventually, her family had to make the heartbreaking decision to take her off life support.
Doctors never officially linked her death to energy drinks, but Barranon remains convinced.
“Doctors said they see this happen a lot with people that do a lot of pre-workout or energy drinks, but they wouldn’t give the cause of death to that,” she said. “I know for a fact that was what was wrong with her.”
Katie Donnell, 28, was a teacher from Florida and “workout queen” who drank up to three energy drinks per day before she died from a heart attack in August 2021. Her mother now reveals it was the caffeine that cost her daughter’s life. She said her daughter “loved the buzz.” pic.twitter.com/AqmpTG48LL
— Te-Erika (@Te_Erika) March 25, 2025
Katie didn’t have any major health issues, but she struggled with severe anxiety, her mother revealed.
“She had horrible anxiety and went to several doctors,” Barranon said. “I don’t think it was real anxiety—I think it was her abuse of caffeine and energy drinks.”
She believes Katie relied on the temporary boost of
caffeine to juggle her workouts, full-time job, and school.
“She thought it’d help her work out and give her more energy,” she told Daily Mail. “I think she got used to the buzz.”
Now, Barranon is warning others about the hidden dangers of energy drinks.
“If you don’t keep your kids away from this stuff, you may be in my situation where your life is ruined,” she said. “It’s so harmful and deadly—my whole family is affected by this.”
What makes energy drinks harmful?
Energy drinks are packed with caffeine, sugar, and other additives like taurine, guarana, and B vitamins. While they promise a quick energy boost, the reality is more complicated.
Caffeine levels in these drinks can range from 80 mg to a staggering 500 mg per can—far more than a standard cup of coffee, which contains around 100 mg. In moderation, caffeine has benefits, such as improving alertness and even lowering the risk of Alzheimer’s and type 2 diabetes. But when consumed in excess, it does more harm than good.
Another major concern is the high sugar content. Many energy drinks are loaded with refined sugar or artificial sweeteners, which can cause blood sugar spikes followed by sudden crashes, Dr Belinda Griffiths of The Fleet Street Clinic explained to The Independent.
Beyond caffeine and sugar, ingredients like guarana, taurine, and ginseng add to the risk. These compounds have stimulant effects that can temporarily enhance alertness, but when combined in high amounts, they may pose serious health concerns.
Can energy drinks cause heart attacks?
Growing research suggests that energy drinks can have a serious impact on cardiovascular health.
A study by the American Heart Association found that consuming just one 900ml energy drink can cause a significant spike in blood pressure and prolong the QT interval—an important measure of electrical activity in the heart.
“This can lead to a rapid heart rate and increased blood pressure before or during exercise. In some cases, this can disrupt the heart’s normal rhythm (arrhythmia), increasing the risk of sudden cardiac arrest,” nutritionist Rakshita Mehra told Healthshots.
But the risks don’t stop at the heart. Energy drinks have also been linked to poor lung health. A 2024 study published in Heart & Lung found a strong connection between caffeine consumption, commonly found in energy drinks, and an increased risk of chronic obstructive pulmonary disease (COPD) and lung function issues.
“The high caffeine content in energy drinks can cause overstimulation of the nervous system, leading to rapid breathing (hyperventilation) or shortness of breath. Excessive sugar in such pre-workout drinks can contribute to chronic inflammation, which may negatively affect lung health over time,” Mehra explained.
With potential risks to both heart and lung health, energy drinks may not be as harmless as they seem.
With input from agencies