{
  "abstract": "Background This meta-analysis investigates the association between abdominal obesity, as measured by waist circumference (WC) and waist-to-hip ratio (WHR), and the risk of colorectal cancer (CRC). Methods We systematically searched PubMed, Scopus, and Google Scholar for relevant English-language prospective cohort studies. Nine studies met the inclusion criteria for the primary meta-analysis, comprising 13,193,908 participants with 131,438 incident CRC cases. Pooled relative risks (RRs) and 95% confidence intervals (CIs) were estimated using a random-effects model. Results Central obesity was associated with a 31% increased risk of CRC (RR = 1.31; 95% CI: 1.25–1.37). The risk was higher in men (RR = 1.41; 95% CI: 1.31–1.52) than in women (RR = 1.26; 95% CI: 1.19–1.34; P for subgroup difference = 0.04). The association was stronger for colon cancer (RR = 1.37; 95% CI: 1.27–1.47) than for rectal cancer (RR = 1.18; 95% CI: 1.11–1.26; P < 0.001). Waist circumference specifically showed a 32% increased risk (RR = 1.32; 95% CI: 1.25–1.41). Studies using measured WC/WHR reported a higher risk (RR = 1.48; 95% CI: 1.36–1.61) than those using self-reported measures (RR = 1.26; 95% CI: 1.20–1.32; P < 0.001). No significant heterogeneity was found by exposure type (WC vs. WHR) or geographic region. Conclusions Central obesity is a significant and independent risk factor for colorectal cancer, with stronger associations observed for colon cancer than for rectal cancer and higher relative risks in men than in women. Visceral fat appears to play a critical role in colorectal carcinogenesis. Maintaining a healthy waist circumference through regular physical activity and a balanced diet remains a key strategy to reduce CRC risk.",
  "abstract_shown": true,
  "affiliations": [
    "Student Research Committee, Iran University of Medical Sciences",
    "Department of Epidemiology, School of Public Health, Tehran University of Medical Sciences",
    "Health Promotion Research Center, Zahedan University of Medical Sciences",
    "Preventive Medicine and Public Health Research Center, School of Medicine, Iran University of Medical Sciences"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Monireh Faghir-Ganji"
    },
    {
      "affs": [
        1
      ],
      "name": "Narjes Abdolmohamadi"
    },
    {
      "affs": [
        2
      ],
      "name": "Alireza Ansari-Moghaddam"
    },
    {
      "affs": [
        3
      ],
      "name": "Babak Eshrati"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/a4faazsmyvxzz.bib",
  "cited_by": 0,
  "doi": "10.1186/s12885-026-16351-1",
  "fulltext_url": "https://doi.org/10.1186/s12885-026-16351-1",
  "id": "a4faazsmyvxzz",
  "issns": [
    "1471-2407"
  ],
  "landing_url": "https://doi.org/10.1186/s12885-026-16351-1",
  "language": "en",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "lcc",
      "RC254-282"
    ],
    [
      "openalex",
      "2730|Cancer Risks and Factors"
    ]
  ],
  "openalex": "W7169838733",
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-07-01",
  "publisher": "BMC",
  "ris": "https://research.draconitic.com/paper/a4faazsmyvxzz.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T13:46:06Z",
      "native_id": "e3f0fc485add4041afa398adaf3a1595",
      "source": "doaj",
      "url": "https://doi.org/10.1186/s12885-026-16351-1"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2730|Cancer Risks and Factors",
      "subfield": "oncology"
    }
  ],
  "title": "Abdominal obesity and colorectal cancer risk: a systematic review and updated meta-analysis",
  "title_text": "Abdominal obesity and colorectal cancer risk: a systematic review and updated meta-analysis",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T13:46:06Z",
  "url": "https://research.draconitic.com/paper/a4faazsmyvxzz",
  "venue": "BMC Cancer",
  "versions": []
}