Popular slimming aid 'can lead to liver and kidney damage and limit effectiveness of anti-cancer drugs'
Alli can cause 'toxicity' in organs and can hamper the effectiveness of medicines including anti-cancer drugs, according to a new studyResearchers in the U.S. claim Orlistat, Alli's active ingredient, inhibits an enzyme that is key to detoxifying the liver and kidney
09:13 GMT, 13 December 2012
Dieters have been warned that using a popular over-the-counter slimming pill could put them at risk of severe organ damage.
A U.S. study has claimed that taking Alli, which helps to block the absorption of fat from food, impacts on a key enzyme within the body and could lead to 'severe toxicity of internal organs such as the liver and kidney'.
Researchers have also claimed the weight-loss aid hampers the effectiveness of medicines including some anti-cancer drugs.
'Wonder drug': Alli claims to aid slimmers with their weight loss – but researchers say taking the pills can lead to organ damage
Rhode Island University's Professor Bingfang Yan, who led the study, has said there has been a 'drastic increase in toxicity' among people using Alli since it was made available over the counter.
Popular: The UK launch of Alli triggered massive sales in 2009
According to a report in the Daily Express, the professor said Orlistat – Alli's active ingredient – inhibits carboxylesterase-2, an enzyme he said works to detoxify the liver, kidney and gastrointestinal tract.
'When the activity of this enzyme drops in those organs, toxicity increases or the efficacy of some drugs is altered,' said Professor Yan.
He said the enzyme's ability to metabolise a wide range of medicines, and that the effectiveness of those medicines – in particular a number of anti-cancer drugs – was at risk of being 'weakened' by the use of Orlistat.
GlaxoSmithKline, which makes the slimming aid, has strongly refuted any suggestion that Alli is unsafe.
'Earlier this year the European regulator reaffirmed the safety profile of Orlistat following a review of the medicine and possible side-effects,' a spokesman said.
The drugs giant also said the results of the U.S. study, which was published in the Biochemical Pharmacology journal, were based on laboratory tests rather than tests on humans, and were inconsistent with data gathered from patients treated with Orlistat.
Alli triggered massive sales when it was launched in the UK in 2009 – 1million worth of the pills were sold on the first day.