Cited by 198Nutritional Studies and DietFood composition and propertiesColorectal Cancer Screening and Detection

Fiber Intake and Survival After Colorectal Cancer Diagnosis

Open access
Song, Mingyang, Wu, Kana, Meyerhardt, Jeffrey A., Ogino, Shuji, Wang, Molin, Fuchs, Charles S., Giovannucci, Edward L., Chan, Andrew T.·2018·JAMA Oncology

Abstract

IMPORTANCE: Although high dietary fiber intake has been associated with a lower risk of colorectal cancer (CRC), it remains unknown whether fiber benefits CRC survivors. OBJECTIVE: To assess the association of postdiagnostic fiber intake with mortality. DESIGN, SETTING, AND PARTICIPANTS: A total of 1575 health care professionals with stage I to III CRC were evaluated in 2 prospective cohorts, Nurses' Health Study and Health Professionals Follow-up Study. Colorectal cancer-specific and overall mortality were determined after adjusting for other potential predictors for cancer survival. The study was conducted from December 23, 2016, to August 23, 2017. EXPOSURES: Consumption of total fiber and different sources of fiber and whole grains assessed by a validated food frequency questionnaire between 6 months and 4 years after CRC diagnosis. MAIN OUTCOMES AND MEASURES: Hazard ratios (HRs) and 95% CIs of CRC-specific and overall mortality after adjusting for other potential predictors for cancer survival. RESULTS: Of the 1575 participants, 963 (61.1%) were women; mean (SD) age was 68.6 (8.9) years. During a median of 8 years of follow-up, 773 deaths were documented, including 174 from CRC. High intake of total fiber after diagnosis was associated with lower mortality. The multivariable HR per each 5-g increment in intake per day was 0.78 (95% CI, 0.65-0.93; P = .006) for CRC-specific mortality and 0.86 (95% CI, 0.79-0.93; P < .001) for all-cause mortality. Patients who increased their fiber intake after diagnosis from levels before diagnosis had a lower mortality, and each 5-g/d increase in intake was associated with 18% lower CRC-specific mortality (95% CI, 7%-28%; P = .002) and 14% lower all-cause mortality (95% CI, 8%-19%; P < .001). According to the source of fiber, cereal fiber was associated with lower CRC-specific mortality (HR per 5-g/d increment, 0.67; 95% CI, 0.50-0.90; P = .007) and all-cause mortality (HR, 0.78; 95% CI, 0.68-0.90; P < .001); vegetable fiber was associated with lower all-cause mortality (HR, 0.83; 95% CI, 0.72-0.96; P = .009) but not CRC-specific mortality (HR, 0.82; 95% CI, 0.60-1.13; P = .22); no association was found for fruit fiber. Whole grain intake was associated with lower CRC-specific mortality (HR per 20-g/d increment, 0.72; 95% CI, 0.59-0.88; P = .002), and this beneficial association was attenuated after adjusting for fiber intake (HR, 0.77; 95% CI, 0.62-0.96; P = .02). CONCLUSIONS AND RELEVANCE: Higher fiber intake after the diagnosis of nonmetastatic CRC is associated with lower CRC-specific and overall mortality. Increasing fiber consumption after diagnosis may confer additional benefits to patients with CRC.

Integrity signals

Registry

Crossref · 10.1001/jamaoncol.2017.3684

Cites

68 of 68 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 23 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    Using cumulative average fiber consumption after diagnosis produced findings similar to the main analysis.

    “Similar findings were obtained when cumulative average fiber consumption after diagnosis was used for the analysis (eTable 2).”
    Quote in the paperNot a substantial claim
  • Findingown data

    In propensity score analysis, the hazard ratio for all-cause mortality per 5-g/day increment in total fiber was 0.86 (95% CI, 0.79-0.93).

    “Similar results were also obtained in the propensity score analysis, with the corresponding HRs of 0.80 (95% CI, 0.67-0.96, P for trend=0.02) and 0.86 (95% CI, 0.79-0.93, P for trend<0.001), respectively, indicating the robustness of our findings to confounding.”
    Quote in the paperSubstantial claim
  • Findingown data

    No further reduction in all-cause mortality was found beyond about 24 g/day of fiber intake.

    “For all-cause mortality, a statistically significant nonlinear relationship was observed (P=0.007); the benefit associated with increasing fiber intake achieved its maximum at about 24 g/day and no further reduction in mortality was found beyond this level of intake (Figure 1).”
    Quote in the paperSubstantial claim
  • Findingown data

    Vegetable fiber intake was associated with lower all-cause mortality (HR per 5-g/day increment, 0.83; 95% CI, 0.72-0.96).

    “Vegetable fiber was associated with lower all-cause mortality (HR per 5-g/day increment, 0.83, 95% CI, 0.72-0.96, P for trend=0.009) but not CRC-specific mortality (HR, 0.82, 95% CI, 0.60-1.13, P for trend=0.22).”
    Quote in the paperSubstantial claim
  • Findingown data

    No other statistically significant interaction was detected in the subgroup analyses.

    “No other statistically significant interaction was detected.”
    Quote in the paperNot a substantial claim
  • May combine two claims. 10
  • Classified as probably not a substantial claim. 8
  • The quote only partly states this claim. 2
  • May combine two claims.

    Findingown data

    The observed 5-year survival rates were 83% for stage I, 82% for stage II, and 72% for stage III colorectal cancer.

    “The overall 5-year survival rates were 83% (95% CI, 79-86%) for stage I cancer, 82% (95% CI, 78-86%) for stage II cancer, and 72% (95% CI, 67-76%) for stage III cancer.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    Pre-diagnostic and post-diagnostic fiber intakes were modestly correlated (Spearman r=0.58).

    “Pre- and post-diagnostic intake of fiber was modestly correlated (Spearman correlation coefficient r=0.58).”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingown data

    In the combined NHS and HPFS cohorts, 1,575 patients with stage I to III colorectal cancer were followed for a median of 8 years, during which 773 deaths occurred, 174 of them from colorectal cancer.

    “Among 1,575 eligible patients diagnosed with stage I to III CRC, we documented 773 deaths, of which 174 were classified as CRC-specific deaths over a median of 8 years of follow-up.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    Among the subset of patients with chemotherapy data, fiber intake was similar between those who received chemotherapy and those who did not.

    “In a subset of patients with chemotherapy data (n=375), fiber intake was similar among those who received chemotherapy (median=19.5 g/day) versus those who did not (median=19.1 g/day) (P for Wilcoxon test =0.13).”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    Patients with higher fiber intake tended to have a healthier lifestyle.

    “Participants with higher fiber intake tended to have a healthier lifestyle (eTable 1).”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Findingown data

    Anatomic subsite and grade of differentiation did not differ across quartiles of fiber intake.

    “Anatomic subsite and grade of differentiation did not differ across quartiles of fiber intake, whereas patients with the highest fiber intake were more likely to have stage I cancer than others.”
    Quote in the paperNot a substantial claim
  • The quote only partly states this claim.

    Findingown data

    The benefit of increasing fiber intake for all-cause mortality reached its maximum at about 24 g/day.

    “For all-cause mortality, a statistically significant nonlinear relationship was observed (P=0.007); the benefit associated with increasing fiber intake achieved its maximum at about 24 g/day and no further reduction in mortality was found beyond this level of intake (Figure 1).”
    Quote in the paperSubstantial claim
  • The quote only partly states this claim.

    Findingown data

    No association was found between fruit fiber intake and mortality.

    “In contrast, no association was found for fruit fiber.”
    Quote in the paperSubstantial claim
  • Classified as probably not a substantial claim.

    Study design and conductnone given

    The study used standardized medical record review of self-reported colorectal cancer and deaths.

    “Advantages of the current study include the prospective design, detailed collection of pre- and post-diagnostic diet and lifestyle information, standardized medical record review of self-reported CRC and deaths, and long-term follow-up.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Premisecitation

    Animal studies have shown that high-fiber diets promote apoptosis and suppress colorectal tumor development.

    “This agrees with the well-established data from animal studies that high-fiber diets promote apoptosis and suppress colorectal tumor development.32–34”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [32] Avivi-Green C Polak-Charcon S Madar Z Schwartz B Dietary regulation and localization of apoptosis cascade proteins in the colonic crypt J Cell Biochem 2000 77 1 18 29 10679813

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [33] Fleiszer D Murray D MacFarlane J Brown RA Protective effect of dietary fibre against chemically induced bowel tumours in rats Lancet 1978 2 8089 552 553 79919

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [34] Cao Y Gao X Zhang W Dietary fiber enhances TGF-beta signaling and growth inhibition in the gut Am J Physiol Gastrointest Liver Physiol 2011 301 1 G156 164 21454444 PMC3129933

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationown data

    Higher whole grain consumption was associated with better survival, and this association was partly mediated by fiber.

    “Higher consumption of whole grains was also associated with better survival, and this beneficial association was partly mediated by fiber.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Premisecitation

    Butyrate is a major energy source for normal colonocytes, is metabolized less in cancer cells due to the Warburg effect, accumulates in the nucleus of cancerous colonocytes, and inhibits histone deacetylase to regulate genes involved in tumor growth, angiogenesis, migration, and chemoresistance.

    “Although butyrate is a major energy source for normal colonocytes, it is metabolized to a lesser extent in cancer cells due to the Warburg effect and accumulates in the nucleus of cancerous colonocytes, in which it functions as an inhibitor of histone deacetylase to epigenetically regulate expression of numerous genes responsible for tumor growth, angiogenesis, migration, and chemoresistance.41”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [41] Encarnacao JC Abrantes AM Pires AS Botelho MF Revisit dietary fiber on colorectal cancer: butyrate and its role on prevention and treatment Cancer Metastasis Rev 2015 34 3 465 478 26224132

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationown data

    Higher intake of fiber and whole grains after colorectal cancer diagnosis is associated with lower death rates from colorectal cancer and other causes.

    “In conclusion, higher intake of fiber and whole grains after CRC diagnosis is associated with lower rate of death from that disease and other causes.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Interpretationown data

    Adjusting for fiber intake attenuated the association between whole grain intake and lower mortality, suggesting that fiber may be an important contributor to the protective effect of whole grains.

    “However, in the current study, adjusting for fiber intake indeed attenuated the association between whole grain and lower mortality, suggesting that fiber may be an important contributor for the protective effect of whole grains.58”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [58] Larsson SC Giovannucci E Bergkvist L Wolk A Whole grain consumption and risk of colorectal cancer: a population-based cohort of 60,000 women Br J Cancer 2005 92 9 1803 1807 15827552 PMC2362029

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • May combine two claims.

    Interpretationown data

    The effect of high fiber intake may extend beyond protection against cancer incidence and contribute to better prognosis after cancer is established.

    “Our current study adds to the existing literature and suggests that the effect of high fiber intake may extend beyond protection against cancer incidence and contribute to better prognosis after cancer is established.”
    Quote in the paperSubstantial claim
  • Classified as probably not a substantial claim.

    Interpretationown data

    The findings support nutritional recommendations to maintain sufficient fiber intake among colorectal cancer survivors.

    “Our findings provide support for the nutritional recommendations of maintaining sufficient fiber intake among CRC survivors.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Premisecitation

    Higher intake of fiber, especially cereal fiber, has been linked to improved insulin sensitivity, lipid profile, endothelial function, and reduced inflammation.

    “Higher intake of fiber, especially cereal fiber, has been linked to improved insulin sensitivity,35 lipid profile,36 endothelial function, and reduced inflammation.37”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [35] Weickert MO Mohlig M Schofl C Cereal fiber improves whole-body insulin sensitivity in overweight and obese women Diabetes Care 2006 29 4 775 780 16567814

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [36] Davy BM Davy KP Ho RC Beske SD Davrath LR Melby CL High-fiber oat cereal compared with wheat cereal consumption favorably alters LDL-cholesterol subclass and particle numbers in middle-aged and older men Am J Clin Nutr 2002 76 2 351 358 12145006

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [37] Qi L van Dam RM Liu S Franz M Mantzoros C Hu FB Whole-grain, bran, and cereal fiber intakes and markers of systemic inflammation in diabetic women Diabetes Care 2006 29 2 207 211 16443861

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationcitation

    The observed stage-specific 5-year survival rates in this cohort appeared comparable to national estimates.

    “These rates appeared to be comparable to national estimates.30”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [30] SEER Cancer Statistics Review, 1975–2013 National Cancer Institute 2016 https://seer.cancer.gov/csr/1975_2013/. Accessed August 02, 2017

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    As an observational study, residual confounding cannot be excluded.

    “Finally, as an observational study, residual confounding cannot be excluded, although we observed similar results through multivariable adjustment and propensity score analysis.”
    Quote in the paperNot a substantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Previous observational data on favorable influences of other lifestyle factors on colorectal cancer survival have subsequently been confirmed in randomized trials.

    “Of note, previous observational data regarding the favorable influence of other lifestyle factors on CRC survival have been subsequently confirmed in randomized trials.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [60] Schmid D Leitzmann MF Association between physical activity and mortality among breast cancer and colorectal cancer survivors: a systematic review and meta-analysis Ann Oncol 2014 25 7 1293 1311 24644304

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [61] Maalmi H Ordonez-Mena JM Schottker B Brenner H Serum 25-hydroxyvitamin D levels and survival in colorectal and breast cancer patients: systematic review and meta-analysis of prospective cohort studies Eur J Cancer 2014 50 8 1510 1521 24582912

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

    • cites [62] Song M Zhang X Meyerhardt JA Marine omega-3 polyunsaturated fatty acid intake and survival after colorectal cancer diagnosis Gut 2016 PMC5247396 27436272

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

20 of 20
  • The authors state this as an assumption.

    Before this study, no prior study had examined the association between fiber intake and survival among colorectal cancer patients.

    “Despite these data, to our knowledge no study has yet examined the association between fiber intake and survival of CRC patients.”
  • The authors state this as an assumption.

    This study is the first prospective study to examine the prognostic influence of fiber intake among colorectal cancer patients.

    “To our knowledge, this is the first prospective study examining the prognostic influence of fiber intake among CRC patients.”
  • The paper relies on this without support.

    During the study period, adjuvant treatment was largely standardized and primarily correlated with disease stage.

    “Moreover, during the time period of the study, adjuvant treatment was largely standardized and primarily correlated with disease stage.”
3 of 3

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • In colorectal cancer patients, greater consumption of fiber, marine omega-3s, vitamin D, calcium, coffee, or a plant-based low-carbohydrate diet has been linked to longer survival.

    “Higher intake of nutrients such as fiber,199 marine omega-3 fatty acid,200–202 vitamin D,203–205 or calcium,203 or coffee206, 207 or a plant-based low-carbohydrate diet207 has been associated with increased survival times of patients with CRC.”

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Conflicting P values for vegetable fiber and CRC-specific mortality

    Minor

    The abstract reports P=0.12, while the Results reports P=0.22 for the same vegetable-fiber association. Both give an HR of 0.82 and a 95% CI of 0.60-1.13.

1 of 1

Cites

Flagged first, then by citations

3 of the 71 references couldn’t be matched to a known paper.

Research works printed but not linked: 1

  1. Prosky, 1985, Determination of total dietary fiber in foods and food products., J Assoc Off Anal Chem, 68, 677

Cited by

Sorted by citations

Authors
Song, M., Wu, K., Meyerhardt, J. A., Ogino, S., Wang, M., Fuchs, C. S., Giovannucci, E. L., & Chan, A. T.
Affiliations
  • Harvard University (US)
  • Brigham and Women's Hospital (US)
  • Yale Cancer Center (US)
  • Broad Institute (US)
Corresponding author
Chan, Andrew T.
Venue
JAMA Oncology
Published
2018-01-01
Volume
4
Issue
1
Pages
71
ISSN
2374-2437 (ISSN-L)
OpenAlex
W2766404639
Cited by
197
References
71
Citations by year
2026: 13 · 2025: 25 · 2024: 25 · 2023: 24 · 2022: 29 · 2021: 20 · 2020: 25 · 2019: 17 · 2018: 19
FWCI
15.64
Type
journal article
Language
en
Open access
Locations
  • JAMA Oncology (publishedVersion)
  • PubMed (publishedVersion)
  • Europe PMC (PubMed Central) (acceptedVersion)
  • PubMed Central (acceptedVersion)
Funders
  • National Institutes of Health (UL1TR001863)
  • National Cancer Institute (R01CA176272, P50CA127003, R01CA202704, R01CA151993, R01CA118553, R01CA137178, R35CA197735, P01CA087969, R01CA169141, P01CA055075, UM1CA186107, UM1CA167552, U01CA176726, U01CA167552)
  • National Institute of Diabetes and Digestive and Kidney Diseases (K24DK098311)
  • National Center for Advancing Translational Sciences
Topics
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Nutritional Studies and Diet
  • Health Sciences › Nursing › Nutrition and Dietetics › Food composition and properties
  • Health Sciences › Medicine › Oncology › Colorectal Cancer Screening and Detection
Keywords
dietary fiber intake, colorectal cancer, cancer survivors, mortality, colorectal cancer-specific mortality, all-cause mortality, cereal fiber, whole grains, Nurses' Health Study, Health Professionals Follow-up Study, healthcare workers
MeSH terms
Cancer Survivors, Adult, Aged, Diet Surveys, Dietary Fiber, Eating, Feeding Behavior, Female, Follow-Up Studies, Health Occupations, Humans, Male, Middle Aged, Prospective Studies, Colorectal Neoplasms, Cohort Studies

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