A spoonful of the fibre that sets jam, taken daily for a month: frail older adults stood up from a chair more easily

Frailty is the slow loss of strength, energy and resilience that makes falls, illness and hospital stays more likely in later life. It often comes with low mood, low-grade inflammation and changes in the gut's bacteria, which has led researchers to ask whether feeding those bacteria could help. Pectin is a soluble fibre found in the cell walls of fruits such as apples, citrus peel and plums, and it is the same ingredient that makes jam set. Gut bacteria ferment it.

A trial from the University of Nottingham, published in GeroScience on 28 September 2026, gave 31 adults with frailty or pre-frailty (average age 74) a daily shake for four weeks. Both groups mixed a powder into 150 ml of milk: 10 g of whey protein and 10 g of cocoa powder, and in the pectin group 10 g of low-methoxy citrus pectin as well. Neither the participants nor the researchers knew who was getting which. Twenty-nine people finished, 15 on pectin and 14 on the placebo shake; one person left because of diarrhoea and one gave no reason.

In the 30-second sit-to-stand test, the pectin group managed about two more stands at the end than at the start (2.07 on average), against 0.71 in the placebo group, a difference that was statistically significant. The timed up-and-go walking test did not change. On a standard anxiety and depression questionnaire (HADS), anxiety scores fell by 1.45 points with pectin against 0.29 with placebo, and depression scores by 1.07 against 0.07. Quality-of-life scores for physical functioning, vitality, mental health and social functioning also favoured pectin. Blood markers of inflammation did not differ between the groups. In the gut, a bacterium called Coprococcus comes, which produces acetate and has been linked to mood, became more common with pectin.

This is a small, short trial, and the authors call it preliminary evidence that needs a larger study. Most participants were pre-frail rather than frail, the per-protocol analysis covered only those who finished, and diet was not recorded during the month. Ten grams of pectin is more than a plate of fruit provides, so the result is about a supplement dose, not about eating an extra apple. Still, it adds to a growing interest in fibre that the gut can ferment as a cheap, well-tolerated lever for wellbeing in older age.