Andres Moreno, known to be the world’s most obese man, died on Christmas Day 2015 due to a heart attack. The Mexican man reportedly consumed huge amounts of an energy drink during the three days before his death.

“He drank more than six cans of energy drinks per day, according to what his family confirmed, but one supposes that the [cause of his death was more than that],” Dr. Jorge Ojeda, head of the intensive care unit at the Mexican America Hospital of Guadalajara, said in an article by Fox News Latino.

Ojeda had reportedly treated Moreno many times before and stated that the energy drinks can lead to fast heartbeats and serious arrhythmias in any individual. The effects can also be aggravated among obese people like Moreno, who weighed as much as 977 lbs.

Ojeda added that in Moreno’s last few days, he suffered from emotional stress due to a conflict with his wife. The doctor ruled out suicide as Moreno’s cause of death, stating that the deceased most likely failed to monitor what he was consuming at the time.

Metro reported that Gastric Bypass Mexico, which previously operated on Moreno, considering his medical background of heart problems and diabetes, his consumption of large amounts of energy drinks at the time was equivalent to an average individual drinking 42 cans of Coca-Cola in 72 hours. He was reportedly drinking more than six energy drinks a day.

Moreno died at 38 years old in Ciudad Obregon in Sonora, two months after the weight-loss surgery was performed on him. Moreno weighed 710 lbs at the time of the operation and has since lost over 132 lbs.

According to Mirror, Moreno lost 19 stone naturally at one point and then had surgery to have part of his stomach removed. He was starting walk again post-surgery and soccer star Cristiano Ronaldo even sent him a signed Real Madrid jersey to inspire him to continue the path to healthy living. However, he relapsed into unhealthy eating and drinking habits.

“As an obese man, although he was losing weight and was starting to move, exposing yourself to a stimulant can cause an irregular heartbeat, and that or a heart attack can lead to death,” Ojeda said in the Mirror report.

The last record-holder for the world’s most obese man was also a Mexican, Manual Uribe, who weighed 88 stone. He died in 2014 at 48 years old.

Moreno’s death should serve as a precaution for overweight individuals who consume energy drinks.