Dietary fibre to reduce side-effects of prostate radiotherapy:DIETRICH
Research type
Research Study
Full title
Phase 2 randomised controlled trial of effects of the DIETary fibRe supplement Inulin versus placebo on intestinal and urinary side effects in men receiving standard of Care radiotHerapy for organ confined prostate cancer
IRAS ID
355096
Contact name
Anne Kiltie
Contact email
Sponsor organisation
University of Aberdeen
Duration of Study in the UK
3 years, 0 months, 0 days
Research summary
One of the treatments for prostate cancer is radiotherapy. Whilst this can help to treat the cancer, it can lead to bowel and bladder complications such as diarrhoea, discomfort, more frequent urination and bleeding. Approximately 1 in 2 men can suffer from these side effects. Side-effects can remain for some time once treatment is completed which leads to further complications and can affect quality of life.
There is evidence that a dietary fibre supplement may help with some radiotherapy side effects. In the DIETRICH study, we want to investigate if men who have their diet supplemented with a dietary fibre source called inulin before radiotherapy starts, during treatment and for a short time after, have fewer gut-associated side effects than those who do not take extra fibre. Inulin is a natural substance from plants such as chicory root. It works by boosting the good bacteria in the gut which helps to reduce inflammation in the lower gut and might lead to fewer side-effects.
We aim to recruit 220 men who have opted for radiotherapy treatment for their prostate cancer. Half the people who take part in DIETRICH will be given a supply of inulin to take for 2 weeks before radiotherapy, 4 weeks during radiotherapy and for 3 weeks after. The other half will receive a treatment which will look and taste similar to inulin but will not include any fibre (placebo treatment). Participants will not know what treatment they are given. Participation in the DIETRICH study will be for a total of 18 weeks. During this time participants will answer some questions on symptoms and diet. Faecal (poo) samples will be collected before and after radiotherapy to study the bacteria and substances in them. This will help us understand how inulin may reduce side-effects and improve gut health.
REC name
London - Central Research Ethics Committee
REC reference
25/LO/0887
Date of REC Opinion
9 Dec 2025
REC opinion
Favourable Opinion