European Food Safety Authority approves inulin-propionate ester fibre additive after trials show mixed weight outcomes

The European Food Safety Authority has approved inulin-propionate ester, or IPE, as safe for use in food. The fibre passes through the stomach and small intestine before bacteria in the large intestine split it to release propionate, which raises short-chain fatty acid levels and triggers greater release of hormones including GLP-1 and PYY.

Gary Frost at Imperial College London said daily consumption of IPE prevented weight gain in a randomised-controlled trial of middle-aged people.

In a separate trial of 270 overweight people aged 20 to 40, those taking IPE showed no difference in body weight after one year but gained an average of more than 1 kg in fat-free mass. A 10-gram daily dose of IPE produces the hormone effect, according to the researchers.

In a trial of 60 overweight people aged 40 to 65, participants who took 10 g IPE daily ate less food and none gained significant weight after six months, while 17 per cent of controls did.

The only reported side effect was increased flatulence. Frost and Douglas Morrison at the University of Glasgow created IPE 15 years ago by attaching propionate to inulin. It took the team 12 years to secure the EU approval.

Morrison said products containing IPE could appear on the market in the EU within 12 months. Frost and Morrison are in discussions with companies to launch IPE in smoothies, cereals and breads. Most people cannot taste the additive, though a very small proportion sense a bitter taste.

The UK regulator is expected to follow the EU decision. The article was amended on 2 July 2026 to correct Gabriel’s stance on the benefits of IPE.