Oral Presentation 49th Nutrition Society of Australia Annual Scientific Meeting 2025

Dietary fibre intake and risk of stomach cancer: a pooled analysis of 21 prospective cohort studies (130061)

Thi Thu Huyen Nguyen 1 2 , Yang Peng 1 3 , Robert J. MacInnis 1 2 , Andrew Haydon 4 , Robin Room 5 6 , Pietro Ferrari 7 , Graham G. Giles 1 2 8 , Roger L. Milne 1 2 8 , Stephanie A. Smith-Warner* 9 10 , Harindra Jayasekara* 1 2 11
  1. Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, Australia
  2. Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
  3. School of Public Health, The University of Queensland, Brisbane, Australia
  4. Department of Medical Oncology, Alfred Hospital, Melbourne, Victoria, Australia
  5. Centre for Alcohol Policy Research, La Trobe University, Melbourne, Australia
  6. Social Research Centre on Alcohol and Drugs, Stockholm University, Stockholm, Sweden
  7. Nutrition and Metabolism, International Agency for Research on Cancer, Lyon Cedex, France
  8. Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, Australia
  9. Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
  10. Department of Nutrition, Harvard T. H. Chan School of Public Health, Boston, MA, USA
  11. School of Public Health and Preventive Medicine, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, Australia

Higher dietary fibre consumption is linked to positive gastric function; however, there is less evidence for associations with risk of stomach cancer(1,2), the fifth most common cancer globally(3). We evaluated associations between energy-adjusted dietary fibre intake and risk of stomach cancer overall and by subtype and population subgroup. Analyses were conducted using data from participants across 21 cohort studies (n = 2,085,078) within the Pooling Project of Prospective Studies of Diet and Cancer. At baseline, total dietary fibre intake, and, in a subset of studies, dietary fibre intake from fruits, vegetables and grains, were assessed. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox regression for incident stomach cancer in relation to dietary fibre intake. We assessed whether associations varied by sex, smoking status, body mass index (BMI), geographical region, or tumour subtype. During follow-up (mean 8 - 23 years across cohorts), 8,629 incident cases of gastric adenocarcinoma (3,072 female, 5,557 male; 1,866 cardia, 4,595 non-cardia) were documented. Large variations in dietary fibre intake were observed across studies. In multivariable models, higher total dietary fibre intake was associated with lower stomach cancer risk for both sexes combined (HR: 0.87; 95% CI: 0.79 - 0.96 ≥ 25 g/day vs < 10 g/day). Using continuous fibre intake, we observed HRs of 0.94 per 10 g/day increment (95% CI: 0.90 - 0.98) for both sexes combined, 0.93 (95% CI: 0.88 - 0.97) for males, and 0.98 (95% CI: 0.91 - 1.05) for females (pinteraction-sex = 0.16). Associations were stronger for current smokers (HR: 0.83 per 10 g/day increment; 95% CI: 0.76 - 0.90; pinteraction-smoking = 0.07), those with BMI < 25 kg/m2 (HR: 0.90; 95% CI: 0.87 - 0.98) and BMI = 25 - 29.9 kg/m2 (HR: 0.94; 95% CI: 0.88 - 1.00) (pinteraction-bmi = 0.06), and studies from Australia/Europe (HR: 0.90; 95% CI: 0.83 - 0.97) and North America (HR: 0.94; 95% CI: 0.89 - 1.00) (pinteraction-region = 0.02). Associations were similar for cardia (HR: 0.94 per 10g/day increment; 95% CI: 0.87 - 1.02) and non-cardia cancers (HR: 0.96; 95% CI: 0.90 - 1.01). Similarly lower risks for total stomach cancer were observed with intake of dietary fibre from grains (HR: 0.87; CI: 0.79 - 0.97 ≥ 8 g/day vs 2 - 4 g/day); association with dietary fibre from vegetables was weak (HR: 0.94; 95% CI: 0.84 - 1.05 ≥ 8 g/day vs 2 - 4 g/day) and with fruits showed increased risk (HR: 1.12; 95% CI: 1.01 - 1.25 ≥ 8 g/day vs 2 - 4 g/day). Our findings support the hypothesis that dietary fibre intake may lead to lower stomach cancer risk. Ongoing analyses will assess possible residual confounding by smoking and H. pylori infection.   

  1. 1. Clinton SK, Giovannucci EL, Hursting SD. J Nutr 2020 Apr;150(4):663–71. 2. World Cancer Research Fund International/American Institute for Cancer Research. Continuous Update Project Report: Diet, Nutrition, Physical Activity and Stomach Cancer 2016. 3. Bray F, et al. CA Cancer J Clin 2024;74(3):229–63.