30 Jun 2021
In recent years there have been significant changes to the advice given when someone is diagnosed with diverticular disease and this blog post is about this common condition and the new advice around what changes, if any, people need to make to prevent infection and to help with symptoms.
Diverticulosis is when the muscular wall of the lower colon weakens and pockets (diverticula) form in the wall of the colon. It is a problem of intestinal muscular function and impaired connective tissue support (Kupcinskas et al 2019). Diverticula tend to develop with increasing age although the diagnosis is becoming more frequent in younger people. (Tursi 2020).
A Westernised diet was thought to contribute to the development of diverticulosis, but evidence that low- fibre diets cause diverticula to develop is conflicting. For lifestyle, there are many confounding variables to consider when reviewing population studies that make a definite cause more difficult to establish.
When diverticula result in symptoms such as lower abdominal pain, bloating, change in bowel habit (diarrhoea or constipation) and mucus or blood in the stool, it is then diagnosed as diverticular disease.
In 2019, the NICE guidelines for diverticular disease were published and diet and lifestyle advice were considered in the evidence review. The British Dietetic Association were stakeholders in this guideline development and a dietitian was a member of the guideline development group.
The guidelines for diverticulosis advise people to eat a healthy, balanced diet including whole grains, fruit and vegetables.
- Tell them that: “there is no need to avoid seeds, nuts, popcorn or fruit skins.” (NICE, 2019)
- If they have constipation and a low-fibre diet, increasing their fibre intake gradually may minimise flatulence and bloating. (NICE, 2019).
Having a diagnosis of symptomatic diverticular disease does not require any alteration to the advice given for diverticulosis (NICE 2019). However, some people may also have a prior diagnosis of IBS (Scarpignato et al 2017) and then dietary advice for IBS may also be appropriate.
Diverticulitis is diagnosed when there is an infection within one or more of the diverticula. There has been a published systematic review that suggests for uncomplicated diverticulitis (i.e., no perforation, non-localised abscess, drains placed, or surgery required, (Dhal et al 2018)) most people will tolerate a more liberalised diet (Dhal et al, 2018). In other words, they do not need a specific low residue or low-fibre diet. The difficulty is defining what a more liberalised diet is with regards to foods. Despite the evidence being reported as very low and the data were heterogeneous, it has been incorporated into the European Society of Coloproctology guidelines (Schultz et al 2020).
There is very little research into diverticular disease and diverticulitis. In England there were 45,841 people admitted to hospital with appendicitis in the year 2019-2020. In the same year there were 160,775 were admitted with diverticulitis (Hospital episode statistics 2019-2020). That is over three times as many, but everybody has heard of appendicitis and very few know about diverticulitis until they are diagnosed.
Until we know more, for people diagnosed with diverticulosis and diverticular disease a healthy varied diet including good sources of fibre from fruit, vegetables and wholegrain sources is the best option. When patients have an uncomplicated diverticulitis, they should be able to tolerate their usual diet.
Kupcinskas J, Strate L, Bassotti G, Torti G, Herszenyi L, Malfertheiner P, Cassieri C, Walker M, Tursi A (2019) Pathogenesis of Diverticulosis and Diverticular Disease Supplement Issue - 3rd International Symposium: Diverticular Disease of the Colon J Gastrointestin Liver Dis, 2019 Vol. 28 Suppl 4: 7
Tursi A, Scarpignato C, Strate LL, Lanas A, Kruis W, Lahat A, Danese S. Colonic diverticular disease. Nat Rev Dis Primers. 2020 Mar 26;6(1):20. doi: 10.1038/s41572-020-0153-5. Erratum in: Nat Rev Dis Primers. 2020 Apr 29;6(1):35. Erratum in: Nat Rev Dis Primers. 2020 Jun 17;6(1):50. PMID: 32218442; PMCID: PMC7486966.
National Institute of Health and Care Excellence (2019) Diverticular Disease (NICE Guideline 147) Available at Overview | Diverticular disease: diagnosis and management | Guidance | NICE
Scarpignato C, Barbara G, Lanas A, Strate LL. Management of colonic diverticular disease in the third millennium: Highlights from a symposium held during the United European Gastroenterology Week 2017. Therapeutic Advances in Gastroenterology. January 2018. doi:10.1177/1756284818771305
Camilla Dahl, Megan Crichton, Julie Jenkins, Romina Nucera, Sophie Mahoney, Wolfgang Marx and Skye Marshall (2018) Evidence for Dietary Fibre Modiﬁcation in the Recovery and Prevention of Reoccurrence of Acute, Uncomplicated Diverticulitis: A Systematic Literature Review Nutrients 2018, 10, 137; doi:10.3390/nu10020137
Schultz J K, Azhar N, Binda G A, Barbara G, Biondo S, Boermeester M A, Chabok A , Consten E C J, Van Dijk S T, Johanssen A, Kruis A, Lambrichts DD , Post S, Ris F, Rockall T A, Samuelsson A, Di Saverio S, Tartaglia D, Thorisson A, Winter D C, Bemelman W and E. Angenete E (2020) European Society of Coloproctology: guidelines for the management of diverticular disease of the colon Volume22, IssueS2 https://doi.org/10.1111/codi.15140
Secondary Care Analytical Team (2020) Hospital Admitted Patient Care Activity 2019-20 England Hospital Admitted Patient Care Activity - NHS Digital
Information Manager, Guts UK
Julie writes evidence based information and articles for the charity and answers queries to the website and over the phone. Prior to this she was a Specialist Gastroenterology Dietitian in the NHS with 12 years’ experience in treating people with diet within the medical and surgical gastroenterology specialisms. She has a specialist interest in functional gastroenterology and has been a published author and a member of the BDA working group developing the UK guidelines on diet and IBS.