Why eating salad while on antibiotics may be bad for you

Dietary changes, including avoiding some greens, could help fight antibiotic resistance

A new study has shown that dietary changes can help reduce the spread of antibiotic resistance. Photo: DCT Abu Dhabi

Avoiding certain vegetables and salads during antibiotic treatment and ensuring food is thoroughly cooked could reduce antibiotic resistance by preventing the bacteria responsible from entering the gut, a study has suggested.

These dietary measures could block bacteria that carry resistance genes from colonising the digestive tract, researchers from the University of Nottingham found.

These resistance genes, found in bacterial DNA, can move between cells, making it easier for bacteria to become resistant to medication.

The study, published in the PLoS One journal, noted that while global strategies against antibiotic resistance have predominantly targeted medication use and hygiene, overlooked factors include the “lifelong acquisition and persistence of resistance genes” in the human gut.

The study assessed 14 antibiotic classes.

Mathematical models simulated resistance gene intake for 1,000 people using various antibiotics.

The findings showed that while the accumulation of resistance genes in the gut relates to the degree of antibiotic use, food preparation and consumption adjustments can decrease the number of these acquired genes.

These reductions are “particularly effective” when people are using antibiotics, the study said.

This led researchers to recommend providing dietary guidance along with antibiotic prescriptions.

Prof Dov Stekel, the study's lead, emphasised the critical period when taking antibiotics.

“When you’re taking antibiotics is exactly when you are most susceptible to creating longer-term problems due to drug-resistant bacteria from food,” he said.

If one consumes food with harmless bacteria that has resistance genes while on antibiotics, “those resistances could become established in your gut ecosystem so next time you need antibiotics they may not work effectively”.

"Resistance genes can be found on fresh products, especially salad vegetables – leaves such as lettuce ... tomatoes, cucumber and roots often eaten raw such as radish and carrot – and other leafy greens such as pak choi," Prof Stekel told The National.

"Consuming bacteria with resistance genes can lead to these genes being transferred to other bacteria that cause infections, such as UTIs or septicaemia."

UK Health Secretary Steve Barclay, during a visit to India, called the issue a “silent killer”.

The study's findings follow the UK government's announcement of a £210 million ($267 million) investment to tackle antibiotic resistance globally.

The investment will help finance the Fleming Fund’s endeavours in Asia and Africa for the next three years, enhancing more than 250 labs across 25 countries.

Prof Stekel said the potential benefits from medical treatment alterations and dietary shifts depend significantly on a country’s antibiotic usage rate.

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