Dear Readers, over the past decade there have been real advances in understanding the role of our microbiome – the community of bacteria (and other organisms) that live on and inside us – in our health. Alongside this, we’ve realised that although antibiotics have had a tremendously beneficial effect on keeping us alive, they can be devastating for this community, wiping out all but a handful of bacteria in our gut. Farmers realised that giving antibiotics to farm animals, even when they weren’t sick, meant that they put on weight more quickly, largely because the drugs killed off many bacteria with a role in healthily processing food, and left only those who turned into fat (gross simplification, but you get the idea).
This has been a concern for hospitals too. One particular bacteria, Enterococcus faecium, increases after antibiotic treatment, and can cause hospital-acquired infection. However, a study at Memorial Sloan Kettering Cancer Centre in New York showed that the drop in microbiome diversity, and the increase in E. facium, was increased by up to 24 percent if the person taking the drugs also had a sugary diet.
The antibiotics kill off most of the beneficial bacteria, and then the sugar seems to act as ‘rocket fuel’ for the remaining ones. Other experiments on mice showed that it was the combination of antibiotics and a sugary diet (even one that included fructose from fruit rather than refined sugar) could cause an increase in ‘bad’ bacteria by up to 33 percent by day six.
Doctors often recommend smoothies and milkshakes to cancer patients, as this is something that they can often tolerate. However, if they are being treated with antibiotics it may be wise to limit them, depending on the situation. It’s certainly something that I’ll be bearing in mind if I need antibiotics at any point – it’s tough enough for the helpful bacteria after being blasted without encouraging the ones that remain.
The advice for rebalancing your microbiome after antibiotics is to eat as wide a range as possible of plants. Our ‘good’ bacteria largely thrive on fibre, which the ‘bad’ ones can’t break down fibre (one reason for the upset tummy that we often get when on the drugs). Though to be honest, cutting down on sugar and eating more fibre is the general advice anyway.
The New Scientist article is here
The research paper is here.