Alexander Fleming’s discovery of penicillin 98 years ago paved the way for what was described as an “antibiotic revolution”.
Many previously untreatable bacterial infections finally met their match – at least until some germs started developing resistance in recent years.
But taking antibiotics has often meant side effects such as nausea and diarrhoea, as well as damage to beneficial gut bacteria.
To limit the fallout, medical researchers are now advising patients to avoid sweets for the prescribed duration, after a five-year study showed sugar could “exacerbate antibiotic-induced microbiome disruption”.
“Our research supports emerging evidence that avoiding sugary foods during antibiotic treatment may protect the microbiome,” said study corresponding author Dr Marcel van den Brink, who is also the chief physician executive at City of Hope, a Los Angeles-based cancer research centre in the United States.
In a paper published in the journal Nature, a team from City of Hope, New York University and Memorial Sloan Kettering Cancer Center said they analysed over 9,000 meals and around 1,000 stool samples from 173 hospital patients described as “particularly high risk for severe gut microbiome disruption and associated side effects”.
The findings could be of particular interest to cancer patients prescribed antibiotics to prevent infections during treatments such as chemotherapy.
“Preserving microbiome diversity has previously been linked with improved clinical outcomes for patients with cancer,” said Dr van den Brink, whose team’s tests were carried out on blood cancer patients put through what City of Hope described as “an intensive treatment called allogeneic haematopoietic cell transplant”.
In March (2026), researchers at Uppsala University warned that a course of antibiotics can “leave traces” in the gut up to eight years later.
“Antibiotics are known gut microbiome disruptors, but their long-term consequences remain underexplored,” the Swedish team explained at the time. – dpa
ALSO READ: Avoid these drinks while taking antibiotics
