Surgeons are warning of the potentially deadly risk posed to young children by button batteries.
If accidentally swallowed, the small, round batteries can get lodged in the oesophagus and burn a hole through its lining.
London's Great Ormond Street Hospital has seen a big increase in cases in the past year.
Surgeon Kate Cross said: "Button batteries should be treated like poison and kept out of reach of children."
Three-year-old Valeria, from Northern Ireland, has been left with permanent damage to her throat after she swallowed a watch battery in April 2015.
The battery became stuck in her food pipe and she began being sick and refusing food.
It was not until five days later that an X-ray showed she had swallowed a battery, by which time it had burned a hole through her oesophagus and windpipe.
Since then she has spent nine months at Great Ormond Street Hospital receiving specialist treatment and still needs to visit every few weeks.
Valeria has undergone dozens of surgical procedures, including having part of her oesophagus removed.
Her mother Jelena said: "Because she now can't eat or drink properly, the doctors have made a hole in her neck and attached a bag so that all her saliva and anything she drinks goes straight in to it.
"Without this, water would go in to her lungs, which would be very dangerous. She also has a special button on her tummy that that liquid food goes through.
"In many ways Valeria is now a normal three-year-old who likes Play-Doh and playing doctors, but she still needs a lot more operations to help her recover."
Doctors are planning to put a metal support, called a stent, into what is left of her oesophagus and they may eventually lift her stomach into her chest to create a new food pipe.
Great Ormond Street Hospital says a decade ago they rarely treated button battery injuries, but there has been a dramatic rise recently, and now are seeing about one child a month.
Kate Cross, consultant neonatal and paediatric surgeon said: "If the battery gets enveloped in the mucosa of the oesophagus it creates an electrical circuit and the battery starts to function, releasing an alkali which is like caustic soda, which can erode through the wall to the windpipe.
"If the battery is facing a different way it can burn into the aorta, a major blood vessel, and there have been cases in Britain where the child has bled to death.
"That is why it is important to get the message out to parents but also other health professionals because this is a time critical problem."
NHS should get a £5bn 'Brexit Bonus' - Lansley
The NHS should get a "Brexit bonus" of £5bn a year, former Conservative Health Secretary Andrew Lansley has said.
Speaking at the NHS Providers annual lecture, Lord Lansley said the public had a right to expect extra funding, which should be in place by 2019-2020.
He also called for ministers to commit to spending 7% of GDP on the NHS.
In the run-up to June's EU referendum, Leave campaigners said the £350m a week the UK paid into the bloc's budget would be spent on the NHS instead.
The figure proved contentious during the campaign, with Remain supporters arguing that figure did not take into account money the UK got back from the EU in grants, subsidies, and the British rebate.
The NHS is currently facing a host of financial challenges brought about by new drugs, treatments and therapies which patients are demanding, the cost of dealing with chronic disease and an increasing and ageing population.
In his speech, Lord Lansley, who was health secretary from 2010 to 2012, said: "At the referendum, on one hand the public were told that staying in would mean a strong economy and more money for the NHS.
"On the other hand the public were told that leaving would mean redirecting the EU budget and more money for the NHS.
"So for political reasons, both campaigns told the public that whatever was going to happen in the future, there would be more money for the NHS.
"So the public have a right to expect it. They have a right to expect a Brexit bonus for the NHS."
He went on to say that the UK would not leave the EU before 2019 at the earliest, so the extra payments should be paid from then.
"It frankly should be no less than £5bn a year," he added.
On the recent junior doctors' dispute, Lord Lansley accused the British Medical Association of being "self-interested" and "nakedly political".
He said the actions of the BMA were in "stark contrast" to his experience of dealing with "real trade unionists" like Dave Prentis, the current Unison general secretary, with whom he negotiated NHS pensions.
'No Proof' fitness trackers promote weight loss
Wearing an activity device that counts how many steps you have taken does not appear to improve the chances of losing weight, research suggests.
The two-year long study in the Journal of the American Medical Association (JAMA) included nearly 500 overweight volunteers who were asked to diet and take more exercise.
Half were given a fitness tracker to help them keep tabs.
This group had lost less weight than the other one by the end of the trial.
The study authors say this does not mean people should ditch the technology altogether, but neither should they put too much faith in them, at least as a slimming aid.
Manufacturers say that the technology has moved on since the study, and that their own research suggests activity trackers can help with weight loss alongside diet and exercise regimes.
Despite the popularity of activity trackers, there have been very few studies to see what actual impact they have on weight and fitness levels.
The University of Pittsburgh research is one of the first randomised trials to gather such evidence.
The investigators found that over the course of the study, the volunteers who wore the fitness trackers had lost, on average, about 8lb (3.6kg).
In comparison, the control group that were not given these devices lost about 13lb (5.9kg).
What do you think? Would you like to see a ban on button batteries? Will Brexit make or break the health secotr? Do you use fitness trackers?
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