EU approves inulin-propionate ester fibre additive for use in foods

The European Food Safety Authority has approved inulin-propionate ester, known as IPE, as safe to eat. The fibre can be added to breads, smoothies and cereals. Products containing IPE could go on sale in the EU within the next year.

IPE stimulates release of the appetite-suppressing hormones GLP-1 and PYY. Ten grams per day of IPE raises blood levels of these hormones. Animal studies indicate that about 80 grams of ordinary fibre would be required for the same effect.

A randomised-controlled trial of 60 overweight people aged 40 to 65 found that none taking IPE gained significant weight after six months, while 17 per cent of controls did. A second trial of 270 overweight people aged 20 to 40 showed no difference in body weight after one year, but participants taking IPE increased fat-free mass by more than one kilogram on average.

The only reported side effect was increased flatulence.

Most people cannot taste added IPE, though a very small proportion sense a bitter taste. Gary Frost at Imperial College London stated that daily consumption prevents weight gain in middle-aged people and produces higher lean body mass in young people. IPE was created 15 years ago by attaching propionate to inulin.

Frost, Douglas Morrison and colleagues spent 12 years obtaining the approval. The UK regulator is expected to follow the EU decision. Frost and Morrison are in discussions with companies about launching IPE-containing products.

The article was amended on 2 July 2026 to correct Brendan Gabriel’s stance on the benefits of IPE.