An elderly man in China lost consciousness and collapsed from hyperkalemia after consuming excessive amounts of bananas, according to local reports.
A man in his 70s living in Ningbo, Zhejiang Province, was transported unconscious to Li Huili Hospital on November 20, according to local media outlets including Ningbo Wanbao and Zhongguo Ningbo Wang on Monday local time.
Tests revealed the man's blood potassium level was 7.9 mmol/L, far exceeding the normal range of 3.5 to 5.5 mmol/L. The medical community considers blood potassium levels of 6.5 mmol/L or higher to be dangerous, requiring immediate treatment.
Abnormalities also appeared in his electrocardiogram, leading to a diagnosis of severe hyperkalemia. At the time, he was reportedly in critical condition that could have led to arrhythmia, ventricular fibrillation, and acute cardiac arrest.
Medical staff immediately moved the man to the emergency intensive care unit. They administered medication to treat the hyperkalemia and protect his heart, and conducted emergency hemodialysis to remove the excess potassium accumulated in his body.
Fortunately, after treatment, the man's blood potassium level returned to the normal range and his electrocardiogram stabilized. He is reported to have moved out of critical condition.
The problem was bananas. The man had suffered from high blood pressure for a long time and had recently felt his entire body weakening with weakness in his legs. People around him told him this could be due to potassium deficiency and that he could simply eat lots of bananas instead of going to the hospital.
He immediately bought bananas and began eating three to four every day. This eating habit continued for half a month. However, his symptoms did not improve and instead worsened, eventually causing him to lose consciousness and be transported to the hospital.
"Healthy people have smooth kidney metabolism, so eating bananas in moderation is fine," said Zhou Ting, deputy director of the emergency department at Li Huili Hospital. "However, elderly people, patients who have taken hypertension medication for long periods, and those with chronic kidney disease have reduced ability to excrete potassium through their kidneys, so consuming large amounts of high-potassium foods such as not only bananas but also oranges, durians, spinach, potatoes, and nuts can be dangerous."
According to U.S. health media outlet Verywell Health, one banana contains approximately 400 mg of potassium. People without kidney disease can eat two to three bananas a day, but those with reduced kidney function risk elevated blood potassium levels if they consume bananas this way.
Potassium is an essential electrolyte needed to maintain muscle and heart function. However, since most potassium that enters the body is excreted through the kidneys, people with reduced kidney function may not excrete it smoothly. In such cases, potassium accumulates in the body and can cause muscle weakness, sensory abnormalities, and arrhythmia, with severe cases potentially leading to cardiac arrest.
Experts advise that feeling weak or excessively fatigued should not automatically be attributed to a deficiency of a specific nutrient. In particular, people who have taken hypertension medication for a long time, those with kidney disease, and the elderly should consult medical professionals before consuming large amounts of high-potassium foods such as bananas over an extended period.
