Does red meat raise cancer and heart disease risk?
Short answer
Linked to higher risk, especially processed meat.
Large long-term studies link red and especially processed meat to more bowel cancer, heart disease and death. The rises are small, and no trial here measured these diseases.
This page says what the research shows. It does not say whether you should eat red or processed meat.
Where the evidence stands
Each dot is one on-topic paper. Steps near the top answer the question more directly. Select a dot to see the study.
↑ Stronger evidence
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Trials in people: cancer and heart disease
Trials that measured cancer, heart disease and death directly.
0Not done yet. This is the step that would answer the question.
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Trials in people: other measures
Trials that measured other health or performance measures.
0None among the papers we read.
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Trials in people: lab tests or safety
Trials that measured lab tests, side effects or safety.
6 -
Population studies
Studies that followed or surveyed groups of people. They show links, not causes.
12 -
Blood levels and genes
Studies that link blood levels or genes to health.
0None among the papers we read.
↓ Weaker evidence
- Points to benefit
- Mixed
- No difference
- No direction
- Points to harm
Not on the ladder: 6 reviews of many studies (shown below), 6 opinion or narrative papers. Counts are papers, not people. Some studies appear in more than one paper.
See every studyWhat we found
- Across 60 long-term studies, the highest red meat eaters had more bowel cancer (HR = 1.15), and so did the highest processed meat eaters (HR = 1.21). Ungvari 2025
- In forty-three pooled studies, every 100 g/day of unprocessed red meat went with more heart and blood vessel disease (HR 1.11); every 50 g/day of processed meat, HR 1.26. Shi 2023
- In 6 US cohorts followed a median 19.0 years, processed and unprocessed red meat each went with slightly higher death from any cause (HR 1.03). Zhong 2020
- Short trials found higher LDL (bad) cholesterol and TMAO, a blood chemical tied to heart risk, on red meat diets; no trial measured cancer or heart disease. Bergeron 2019, Ferreira 2026, Bäck 2025
What the research says
Bowel cancer links are the most consistent
Pooled long-term studies link both red and processed meat to more bowel cancer (HR = 1.15 and 1.21 across 60 studies). In UK Biobank, eating 76 g/day of red and processed meat vs 21 g/day went with 20% higher risk.
A German study found risk rose with intake: 19%, 41% and 73% higher at rising amounts, at every level of gene risk. An older review of 35 studies disagreed: it called most links weak and said red meat could not be separated from other habits.
Studies: Ungvari 2025, Farvid 2021, Bradbury 2020, Chen 2022, Alexander 2011
Heart disease and death: small but repeated links
Across forty-three studies, unprocessed red meat (per 100 g/day, HR 1.11) and processed meat (per 50 g/day, HR 1.26) went with more heart and blood vessel disease. In six US cohorts, each 2 extra servings a week went with small rises in heart disease and death.
Both meats went with HR 1.03 for death, which the authors call a small rise. A computer model estimated a 30% cut in both meats could prevent 382 400 cases of heart and blood vessel disease in the USA over 10 years; it rests on assumed risks.
Studies: Shi 2023, Zhong 2020, Kennedy 2024
Processed meat and red meat do not always agree
Some studies split the two. In Norwegian women, processed meat above 30 g/d went with more deaths, while red meat was neutral or beneficial. In Korean women, processed meat went with 57 % higher breast cancer risk; beef's result (HR = 0.82) had a range including no difference.
The reverse also appears. In French adults, red meat went with more cancer overall (1.31) and breast cancer, but processed meat, eaten in small amounts, did not. Among people with HIV in Tanzania, red meat 4 or more times a week went with lower death (HR: 0.54).
Studies: Enget Jensen 2024, Lee 2025, Diallo 2018, Abioye 2023
Other cancers: lung links, breast and stomach unclear
In UK Biobank, each 50 g/d of red meat went with more lung cancer (HR 1.36), and each 25 g/d of processed meat too (HR 1.30). A review of 72 meta-analyses linked red meat to cancer death and several cancers, with 11%-51% higher risk per 100 g/d.
Results for single cancers are less steady. For breast cancer, one pooled analysis found 1.05 (1.00, 1.11), a range touching no difference. For stomach cancer, red meat 4 or more times a week gave 1.31 (95% CI, 0.87 to 1.96), also unclear.
Studies: Wei 2021, Huang 2021, Poorolajal 2021, Poorolajal 2020
Short trials measured only markers
Trials lasted one meal to 6 weeks and measured only markers. Red and white meat both raised LDL (bad) cholesterol compared with nonmeat protein. Swapping some red and processed meat for beans lowered LDL cholesterol and weight. A plant-based meat diet gave lower TMAO, a heart-risk blood chemical.
Two small trials, one funded by a beef group and one with meat industry support, found no harm: beef patties did not worsen artery function, and beef or lamb meals raised blood fats slightly less than a plant burger. Red meat intake tracked a cancer-linked stool chemical in obese men.
Studies: Bergeron 2019, Bäck 2025, Ferreira 2026, Lytle 2023, Pham 2025, Holtrop 2012
What reviews of many studies found
Reviews pool or sum up earlier studies. They are not on the ladder, because they repeat studies already counted there.
Pooled review (meta-analysis) · Ungvari 2025
Pooled 60 prospective studies. High red meat (HR = 1.15) and processed meat (HR = 1.21) intake both went with more colorectal cancer, with similar links for colon and rectal cancer.
Pooled review (meta-analysis) · Shi 2023
Pooled forty-three observational studies (4 462 810 people) on heart and blood vessel disease. Unprocessed red meat (HR 1.11 per 100 g/day) and processed red meat (HR 1.26 per 50 g/day) both went with higher risk.
Pooled review (meta-analysis) · Farvid 2021
Pooled 148 published articles on cancer. High red meat went with more breast, endometrial, colorectal, lung and liver cancer; high processed meat with more breast, colorectal and lung cancer.
Systematic review · Huang 2021
Reviewed 72 meta-analyses. Red meat was linked to cancer death and several cancers. Each 100 g/d of red meat and 50 g/d of processed meat went with 11%-51% and 8%-72% higher risk.
How the research grew
The papers we read span 2009 to 2026. 8 of the 30 on-topic papers came out in 2024 to 2026. The earliest trial in people here is from 2012.
- 2009
- 2011
- 2012
- 2014
- 2015
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
Each dot is one on-topic paper, colored by what it found. Rings mark key papers:
- 2011. Review of 35 studies calls bowel cancer links weak. Alexander 2011
- 2014. Review notes 2007 report called bowel cancer link convincing. Abid 2014
- 2017. Review after WHO cancer agency rated meat carcinogenic. Johnson 2017
- 2021. Umbrella review of 72 meta-analyses on cancer. Huang 2021
- 2023. Largest heart disease pool: 4 462 810 people. Shi 2023
Who was studied
Who took part, and how many. The largest trial here had 113 people; the largest population study had 475,581.
- Trials in people
- Population, blood and gene studies
- 46,551 people · Shaukat 2017
Adults aged 50 to 80 in a Minnesota bowel cancer screening trial, followed 30 years - People in the study, log scale1101001,00010,000100,0001,000,000
- Points to benefit
- Mixed
- No difference
- No direction
- Points to harm
Bars use a log scale: each step is ten times more people. Reviews, animal studies and papers with no count in the abstract are not shown.
Who funds this research
2 of 6 trial papers have a company stake: one funded by the National Cattlemen's Beef Association, one with Meat Industry Association support. Both found no harm from beef or lamb. They measured only markers, so they did not change the confidence.
- Company stake 2
- No disclosure in PubMed 2
- No stake declared 2
- Pham 2025Company stake
- Lytle 2023Company stake
- Bergeron 2019No disclosure in PubMed
- Holtrop 2012No disclosure in PubMed
- Bäck 2025No stake declared
- Ferreira 2026No stake declared
Funding rule. A stake is always shown. Confidence is lowered only when every supporting study comes from a party with a stake. "No disclosure in PubMed" means the PubMed record has no conflict-of-interest statement. It does not mean there is no conflict.
All 30 on-topic papers
Each paper shows what it tested, what it found, and who has a stake. Every paper also has its own page that explains how much it counts and how it fits. See every study as a list.
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Processed plant-based meat-supplemented diet versus red meat-based supplemented diet randomized cross-over trial Finding Optimal Oral Diet-1 (FOOD-1) trial.
41 people · Adults, median age 51, a third with artery disease
TestedDiet with red meat vs diet with plant-based meat, 6 days each
A blood chemical linked to heart risk (TMAO) was lower on the plant-based meat diet: -0.61 log units (95% CI -0.90 to -0.33, P < 0.001). LDL cholesterol was lower too, by -6.0 mg/dL; body weight was higher by + 0.6 kg.
Points to harmNo stake declaredAbstract onlyAuthors report ties to drug companies, none to meat or plant-based meat makers.
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Randomized trial · lab tests or safetyPham et al., 2025The American journal of clinical nutrition · PubMed
Plasma chylomicron-rich lipidomic and fatty acid profile following a meat or analog meal in healthy males: A randomized controlled trial.
27 people · Healthy young men
TestedOne meal with grain-fed beef, grass-fed beef, lamb or a plant-based burger, blood tested for 4 hours
Blood fat responses differed only a little between meals. Grain beef and lamb gave a lower blood triglyceride rise than the plant burger (grain: -0.346; 95% CI: -0.692, -0.0004).
Points to benefitCompany stakeAbstract onlySome authors received support from the Meat Industry Association.
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Nutritional and health benefits of a partial substitution of red and processed meat with non-soy legumes: a 6-week randomized controlled trial in healthy working-age men.
102 people · Healthy working-age men, average age 38
Tested760 g a week of red and processed meat vs 200 g a week plus bean foods, for 6 weeks
The bean group had lower total and LDL cholesterol (both P < 0.001), BMI and weight (both P = 0.009). They also had lower vitamin B12 status (P = 0.022) and iodine status (P = 0.041).
Points to harmNo stake declaredAbstract onlyNo competing interests declared.
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Assessment of Vascular Function in Response to High-Fat and Low-Fat Ground Beef Consumption in Men.
23 people · Men averaging 40 years old
Tested5 beef patties a week, high-fat or low-fat, for 5 weeks each, added to usual diet
High-fat beef improved artery widening (FMD) and lowered blood pressure compared with entry. Neither beef type changed pulse wave velocity. Neither beef harmed artery function.
Points to benefitCompany stakeAbstract onlyFunded by the National Cattlemen's Beef Association.
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Randomized trial · lab tests or safetyBergeron et al., 2019The American journal of clinical nutrition · PubMed
Effects of red meat, white meat, and nonmeat protein sources on atherogenic lipoprotein measures in the context of low compared with high saturated fat intake: a randomized controlled trial.
113 people · Healthy men and women aged 21 to 65
TestedDiets with red meat, white meat, or no meat protein, 4 weeks each, with high or low saturated fat
LDL (bad) cholesterol was higher with red and white meat than with nonmeat protein (P < 0.0001). Red and white meat did not differ. Heart disease itself was not measured.
Points to harmNo disclosure in PubMedAbstract onlyNo disclosure in PubMed; funded by US National Institutes of Health.
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Diet composition is associated with endogenous formation of N-nitroso compounds in obese men.
Obese men on weight-loss or weight-keeping diets in three diet trials
TestedMeat-based weight-loss diets and red meat intake, and cancer-causing chemicals (NOC) in stool
Meat-based weight-loss diets raised stool NOC (P < 0.001). Red meat intake correlated with stool log NOC (r = 0.60; P < 0.001).
Points to harmNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Meat intake and breast cancer risk from the Health Examinees study.
71,264 people · Korean women aged 40 to 69; 713 got breast cancer
TestedEating processed meat, beef and other meat vs none
One or more servings of processed meat a week went with 57 % higher breast cancer risk (HR = 1.57, 95 % CI: 1.09-2.27). Beef went with lower risk (HR = 0.82, 95 % CI: 0.67-1.01), a range that touches 1.
Points to harmNo stake declaredAbstract onlyNo competing interests declared.
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Association of ultra-processed food consumption with all cause and cause specific mortality: population based cohort study.
114,064 people · 74,563 women and 39,501 men health workers followed about 30 years
TestedHighest vs lowest fourth of ultra-processed food, including ready-to-eat meat, poultry and seafood products
Ready-to-eat meat, poultry and seafood products (for example, processed meat) were linked to higher death risk, with hazard ratios from 1.06 to 1.43. Ultra-processed food overall had 4% higher death from any cause, but no link with cancer or heart disease death.
Points to harmNo stake declaredAbstract onlyOne author had a consulting fee from the Pan American Health Organization; not a food company.
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Population study: followed a groupEnget Jensen et al., 2024The British journal of nutrition · PubMed
Replacing red and processed meat with lean or fatty fish and all-cause and cause-specific mortality in Norwegian women. The Norwegian Women and Cancer Study (NOWAC): a prospective cohort study.
83,304 people · Norwegian women followed about 21 years; 9420 died
TestedEating red and processed meat, and swapping 20 g/d of it for fish
Processed meat (> 30 g/d) was linked to higher death risk, while red meat was neutral or beneficial. In high processed meat eaters, swapping 20 g/d for lean fish went with lower all-cause death (HR 0·92, 95 % CI 0·89, 0·96).
MixedNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Population study: followed a groupAbioye et al., 2023Journal of acquired immune deficiency syndromes (1999) · PubMed
Dietary Iron Intake and HIV-Related Outcomes Among Adults Initiating Antiretroviral Therapy in Tanzania.
2,293 people · Adults in Tanzania with HIV starting HIV drugs
TestedEating red meat 4 or more times a week vs 0-1 times a week
Red meat 4 or more servings a week was linked to lower death from any cause (HR: 0.54; 95% CI: 0.35 to 0.83) than 0-1 servings. 175 people died.
Points to benefitNo stake declaredAbstract onlyNo conflicts of interest to disclose.
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Population study: cases vs controlsLewandowska et al., 2022Cancer control : journal of the Moffitt Cancer Center · PubMed
Risk Factors for the Diagnosis of Colorectal Cancer.
800 people · 400 Polish patients with bowel cancer and 400 people without it
TestedComparing habits of people with and without bowel cancer, including red meat
Higher red meat and fat intake went with more bowel cancer (P < .01). Smoking, obesity, low activity and high salt were also linked.
Points to harmNo stake declaredAbstract onlyNo competing interests declared.
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Red and Processed Meat Intake, Polygenic Risk Score, and Colorectal Cancer Risk.
9,243 people · 5109 German people with bowel cancer and 4134 without
TestedEating red and processed meat multiple times a week, once a day, or more, vs once a week or less
Red and processed meat was linked to 19% (95% CI 1% to 41%), 41% (18% to 70%), and 73% (30% to 132%) higher bowel cancer risk at rising intakes. The link held at all gene risk levels.
Points to harmNo stake declaredAbstract onlyNo competing interests declared; funders had no role.
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Population study: followed a groupWei et al., 2021The American journal of clinical nutrition · PubMed
Diet and Risk of Incident Lung Cancer: A Large Prospective Cohort Study in UK Biobank.
416,588 people · UK adults followed a median 7.13 years; 1782 got lung cancer
TestedEach extra 50 g a day of red meat and 25 g a day of processed meat
More red meat went with more lung cancer (HRper 50 g/d: 1.36; 95% CI: 1.13, 1.65). Processed meat too (HRper 25 g/d: 1.30; 95% CI: 1.10, 1.53).
Points to harmNo disclosure in PubMedAbstract onlyNo disclosure in PubMed; funded by UK Medical Research Council.
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Population study: followed a groupBradbury et al., 2020International journal of epidemiology · PubMed
Diet and colorectal cancer in UK Biobank: a prospective study.
475,581 people · UK adults aged 40 to 69, followed about 5.7 years
TestedEating 76 g/day of red and processed meat vs 21 g/day
Eating 76 g/day of red and processed meat vs 21 g/day went with a 20% [95% confidence interval (CI): 4-37] higher risk of bowel cancer. 2609 cases occurred.
Points to harmNo disclosure in PubMedAbstract onlyNo disclosure in PubMed; funded by Cancer Research UK and public bodies.
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Associations of Processed Meat, Unprocessed Red Meat, Poultry, or Fish Intake With Incident Cardiovascular Disease and All-Cause Mortality.
29,682 people · US adults from 6 long-term studies followed about 19 years
TestedEach extra 2 servings a week of processed meat, unprocessed red meat, poultry or fish
Heart disease risk was higher with processed meat (adjusted HR, 1.07 [95% CI, 1.04-1.11]) and unprocessed red meat (adjusted HR, 1.03 [95% CI, 1.01-1.06]). Death from any cause was also higher (HR, 1.03 for each). Fish showed no link.
Points to harmNo stake declaredAbstract onlyOne author had a small consulting fee from a drug company, unrelated to meat.
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Red and processed meat intake and cancer risk: Results from the prospective NutriNet-Santé cohort study.
61,476 people · French adults aged 35 and over followed for cancer
TestedHighest vs lowest fifth of red meat and processed meat intake
Red meat linked to more cancer overall (HRQ5vs.Q1 =1.31 (1.10-1.55)) and breast cancer (HRQ5vs.Q1 = 1.83 (1.33-2.51)). No link with prostate cancer. Processed meat was not linked to cancer.
Points to harmNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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BMI Is a Risk Factor for Colorectal Cancer Mortality.
46,551 people · Adults aged 50 to 80 in a Minnesota bowel cancer screening trial, followed 30 years
TestedDiet and lifestyle habits, including meat intake, and later death from bowel cancer
Higher BMI raised bowel cancer death risk (HR 1.03; 95% CI 1.00-1.05). Intakes of meats were not associated with bowel cancer death.
No differenceNo disclosure in PubMedAbstract onlyNo disclosure in PubMed; funded by US government sources.
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Population study: followed a groupWagemakers et al., 2009European journal of clinical nutrition · PubMed
Consumption of red or processed meat does not predict risk factors for coronary heart disease; results from a cohort of British adults in 1989 and 1999.
1,152 people · 517 men and 635 women from a British 1946 birth group
TestedRed and processed meat eaten in 1989 and 1999 vs heart risk factors measured in 1999
Red or processed meat was not linked to blood cholesterol or blood pressure, except higher blood pressure in men for both combined. A 10 g increase in red meat went with a 0.3 cm bigger waist (P=0.04 for men).
MixedNo disclosure in PubMedAbstract onlyNo disclosure in PubMed; funded by UK Medical Research Council.
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Association between red and processed meat consumption and colorectal cancer risk: a comprehensive meta-analysis of prospective studies.
60 studies · Adults in 60 long-term studies of meat eating and bowel cancer
TestedHighest vs lowest red meat, processed meat, and total meat intake
Red meat linked to more colorectal cancer (HR = 1.15, 95% CI 1.10-1.21). Processed meat also linked to more colorectal cancer (HR = 1.21, 95% CI 1.14-1.28).
Points to harmNo stake declaredAbstract onlyNo company ties declared; authors are journal editors; funded by US National Institutes of Health.
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Red meat consumption, cardiovascular diseases, and diabetes: a systematic review and meta-analysis.
43 studies, 4,462,810 people · Adults in 43 long-term studies of heart disease (plus 27 studies of diabetes)
TestedMore unprocessed red meat (per 100 g/day) and processed red meat (per 50 g/day)
Heart disease risk was higher with unprocessed red meat (HR 1.11, 95% CI 1.05 to 1.16 per 100 g/day) and processed red meat (HR 1.26, 95% CI 1.18 to 1.35 per 50 g/day). Diabetes risk was also higher.
Points to harmNo stake declaredAbstract onlyNo competing interests declared.
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Consumption of red meat and processed meat and cancer incidence: a systematic review and meta-analysis of prospective studies.
148 studies · Adults in long-term studies that tracked meat eating and later cancer
TestedHighest vs lowest group of red meat, processed meat, and both together
Highest red meat intake linked to more breast (RR = 1.09), colorectal (RR = 1.10; 95% CI = 1.03-1.17) and lung cancer (RR = 1.26), among others. Processed meat linked to 18% more colorectal and 6% more breast cancer risk.
Points to harmNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Red and processed meat consumption and cancer outcomes: Umbrella review.
72 studies · People in 72 earlier meta-analyses of meat eating and cancer
TestedRed meat (per 100 g/day) and processed meat (per 50 g/day) vs less
Red meat linked to higher risk of death from cancer overall and of several cancers including colorectal and lung. Each 100 g/d of red meat linked to 11%-51% higher risk; each 50 g/d of processed meat to 8%-72%.
Points to harmNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Factors for the Primary Prevention of Breast Cancer: A Meta-Analysis of Prospective Cohort Studies.
197 studies, 19,413,702 people · Women in 197 long-term studies of 15 factors and breast cancer
TestedRed meat eating (comparison groups not stated in abstract), one of 15 factors checked
For red meat and breast cancer, the risk ratio was 1.05 (1.00, 1.11). The range touches 1.00, so no clear link.
No differenceNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Risk factors for stomach cancer: a systematic review and meta-analysis.
232 studies, 33,831,063 people · People in 232 studies of habits and stomach cancer
TestedEating red meat 4 or more times a week vs less, one of 14 factors checked
For red meat 4 or more times a week and stomach cancer, the odds ratio was 1.31 (95% CI, 0.87 to 1.96). The range includes 1, so no clear link.
No differenceNo stake declaredAbstract onlyNo conflicts of interest declared; funded by a university.
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Estimated effects of reductions in processed meat consumption and unprocessed red meat consumption on occurrences of type 2 diabetes, cardiovascular disease, colorectal cancer, and mortality in the USA: a microsimulation study.
8,665 people · A computer model of US adults built from a national survey of 8665 people
TestedComputer model of eating 30% less processed meat, red meat, or both over 10 years
The model estimated a 30% cut in both meats could prevent 382 400 heart disease cases, 84 400 bowel cancer cases and 62 200 deaths in 10 years. The authors say red meat effects are less certain.
No weight on the ladderNo stake declaredAbstract onlyNo competing interests declared; funded by Wellcome Trust.
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Potential health hazards of eating red meat.
Adults in long-term studies of red meat and chronic disease
TestedUnprocessed red meat (100 g/day) and processed meat (50 g/day) vs less
Per 100 g a day of unprocessed red meat, risk was 15% higher for heart disease death and 17% higher for bowel cancer. Per 50 g a day of processed meat, risk was 22% higher for total death and 24% higher for heart disease death.
No weight on the ladderNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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The cancer risk related to meat and meat products.
People in studies behind the WHO cancer agency's meat rating
TestedRed and processed meat eating and cancer
Processed meat is linked to higher bowel cancer risk. Evidence for red meat and for other cancers is tentative. How much avoiding meat protects is unclear.
No weight on the ladderNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Opinion or narrative reviewBattaglia Richi et al., 2015International journal for vitamin and nutrition research. Internationale Zeitschrift fur Vitamin- und Ernahrungsforschung. Journal international de vitaminologie et de nutrition · PubMed
Health Risks Associated with Meat Consumption: A Review of Epidemiological Studies.
Men and women in large US and European long-term studies
TestedLong-term eating of more red meat and processed meat
More red meat, and especially processed meat, was linked to higher risk of death, heart disease, bowel cancer and type 2 diabetes. White meat showed no such link. The authors advise caution in people above about 70.
No weight on the ladderNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
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Meat, dairy, and cancer.
People in US National Cancer Institute studies and later meta-analyses
TestedRed and processed meat, and dairy, and cancer
A 2007 expert report judged the link between red and processed meat and bowel cancer as convincing. Links with other cancers are unclear.
No weight on the ladderNo disclosure in PubMedAbstract onlyNo disclosure in PubMed; funded by the US National Institutes of Health.
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Opinion or narrative reviewAlexander et al., 2011Obesity reviews : an official journal of the International Association for the Study of Obesity · PubMed
Red meat and colorectal cancer: a critical summary of prospective epidemiologic studies.
People in 35 long-term studies of red meat and bowel cancer
TestedHigher vs lower red meat intake
Links between red meat and bowel cancer were generally weak, with most relative risks below 1.50 and no clear dose-response. The authors say the evidence does not support an independent link.
No weight on the ladderNo disclosure in PubMedAbstract onlyNo disclosure in PubMed.
24 papers we read and set aside as off topic
- Farinetti et al., 2017. Mediterranean diet and colorectal cancer: A systematic review. (systematic review)
- English et al., 2021. Evaluation of Dietary Patterns and All-Cause Mortality: A Systematic Review. (systematic review)
- Chu et al., 2025. Dietary patterns and colorectal cancer risk: Global Cancer Update Programme (CUP Global) systematic literature review. (systematic review)
- Capodici et al., 2024. Cardiovascular health and cancer risk associated with plant based diets: An umbrella review. (systematic review)
- Berrino et al., 2024. The Effect of Diet on Breast Cancer Recurrence: The DIANA-5 Randomized Trial. (randomized trial)
- Cruz-Cobo et al., 2024. Efficacy of a Mobile Health App (eMOTIVA) Regarding Compliance With Cardiac Rehabilitation Guidelines in Patients With Coronary Artery Disease: Randomized Controlled Clinical Trial. (randomized trial)
- Hernáez et al., 2020. Mediterranean Diet and Atherothrombosis Biomarkers: A Randomized Controlled Trial. (randomized trial)
- Ferrell et al., 2021. Fecal Microbiome Composition Does Not Predict Diet-Induced TMAO Production in Healthy Adults. (randomized trial)
- Hunt et al., 2003. Cancer prevention for working class, multiethnic populations through small businesses: the healthy directions study. (randomized trial)
- Onali et al., 2025. Berry supplementation in healthy volunteers modulates gut microbiota, increases fecal polyphenol metabolites and reduces viability of colon cancer cells exposed to fecal water- a randomized controlled trial. (randomized trial)
- Li et al., 2025. A WeChat-Based Decision Aid Intervention to Promote Informed Decision-Making for Family Members Regarding the Genetic Testing of Patients With Colorectal Cancer: Randomized Controlled Trial. (randomized trial)
- Emmons et al., 2014. A randomized comparative effectiveness study of Healthy Directions 2--a multiple risk behavior intervention for primary care. (randomized trial)
- Mangravite et al., 2011. Changes in atherogenic dyslipidemia induced by carbohydrate restriction in men are dependent on dietary protein source. (randomized trial)
- Zaharek-Girgasky et al., 2015. Diet-Related Colorectal Cancer Prevention Beliefs and Dietary Intakes in an Urban Minority Population. (population study: one-time survey)
- Compton et al., 2025. Dietary quality and chemotherapy-induced peripheral neuropathy in colon cancer. (population study: followed a group)
- Roberts et al., 2022. SWAP-MEAT Athlete (study with appetizing plant-food, meat eating alternatives trial) - investigating the impact of three different diets on recreational athletic performance: a randomized crossover trial. (randomized trial)
- Wedekind et al., 2019. Syringol metabolites as new biomarkers for smoked meat intake. (other)
- Song et al., 2020. Influence of the Gut Microbiome, Diet, and Environment on Risk of Colorectal Cancer. (opinion or narrative review)
- Pan et al., 2019. Diet and colon: what matters? (opinion or narrative review)
- Chazelas et al., 2022. Nitrites and nitrates from food additives and natural sources and cancer risk: results from the NutriNet-Santé cohort. (population study: followed a group)
- Lippi et al., 2015. Red meat, processed meat and the risk of venous thromboembolism: friend or foe? (systematic review)
- Jafari et al., 2023. Ultra-Processed Food Intake and Risk of Colorectal Cancer: A Matched Case-Control Study. (population study: cases vs controls)
- Patel et al., 2024. Legume intake and cancer risk in a network of case-control studies. (population study: cases vs controls)
- Avraham et al., 2024. Methodology and challenges for harmonization of nutritional data from seven historical studies. (other)
Words on this page
- Hazard ratio (HR)
- Compares how often something happened in two groups over time. 1 means no difference. 0.80 means 20% lower risk; 1.20 means 20% higher.
- Relative risk (RR)
- Compares the risk in two groups. 1 means no difference. 0.85 means 15% lower risk.
- Odds ratio (OR)
- Another way to compare two groups. 1 means no difference. Below 1 means lower odds, above 1 higher odds.
- 95% CI (confidence interval)
- The range where the true result likely lies. If the range includes no effect (1 for ratios, 0 for differences), the result is not clear.
- p-value (p =)
- How likely a result this large would be by chance if there were no real effect. Below 0.05 is usually called a clear result.
- Pooled review (meta-analysis)
- A study that combines the results of many earlier studies to get one overall answer.
- Cohort study
- A study that follows a large group of people over years. It shows links, not causes.
- Marker
- A lab or scan result that stands in for a health outcome. A better marker does not always mean better health.
How the short answer is set
Fixed rules turn the studies into the short answer, so the same studies always give the same answer. The rules start from GRADE, a standard system for rating evidence, in plain language.
| Confidence | What it means |
|---|---|
| High | We are confident the answer is right. |
| Moderate | The answer is probably right, but it could change. |
| Low (this page) | The answer may well change. |
| Very low | Any answer is very uncertain. |
| Not tested in people | Only cell or animal studies exist. |
Why low here
- Only population studies measured cancer, heart disease or death; they show links, not causes.
- Pooled studies agree on bowel cancer and heart disease, but the rises are small.
- Results for unprocessed red meat vary more than for processed meat.
- Trials lasted one meal to 6 weeks and measured only markers, like cholesterol.
Hard limit used. With no human trial of cancer, heart disease or death, these studies show links, not proof that red or processed meat causes them.
How this page was made
Label
- Search
- PubMed, Nov 14, 2026. Searches written by Claude Opus 5.5; papers ranked by PubMed
- First read of all 54 papers
- Claude Sonnet
- Independent second read
- Claude Haiku
- Disagreements settled by
- Claude Opus 5.5
- Page text written by
- Claude Opus 5.5
- Charts
- Drawn by code from the study records
- Source check by a person
- Not yet. Required before search engines may list this page.
- Expert review
- No
- Papers read in full
- 0 of 54; all from PubMed abstracts
- Method
- v0.2, created Nov 14, 2026
Search. We ran four PubMed searches for red and processed meat and cancer, heart disease and death: pooled and systematic reviews since 2012 (10 of 187), trials in people (22 of 131), population studies (22 of 1,203). The first number is how many papers we read; the second is how many PubMed found. We took the ones PubMed ranks as most relevant. See the full PubMed search. Of the 54 papers read, 30 were on topic.
Limits. Digestery reads at most about 60 papers per question, so large fields are sampled, not covered in full. Abstracts can leave out key details, such as side effects and funding.
Review queue
These items wait for a person. Search engines are asked not to list the page until the first one is done.
- OpenThe short answer is new. It waits for a source check by a person.
- OpenFang 2024 pools processed meat with poultry and seafood ready-to-eat products; set relevant. Check it fits the topic.
- OpenLippi 2015 (vein blood clots) set not relevant; reader A had it relevant. Confirm vein clots fall outside heart disease.
- OpenMarker-only papers (Bergeron 2019, Bäck 2025, Ferreira 2026, Lytle 2023, Pham 2025, Holtrop 2012, Wagemakers 2009) kept relevant only as markers.
- OpenMeta-analyses Farvid 2021, Ungvari 2025, Huang 2021 and Shi 2023 likely share cohorts, so their results are not independent.
- OpenBergeron 2019 and off-topic Ferrell 2021 share trial registration NCT01427855.
- Open16 relevant papers have no conflict statement in PubMed, including the large meta-analyses Farvid 2021 and Huang 2021.
- OpenBerrino 2024 (DIANA-5) cut red meat inside a whole-diet change and saw no effect on recurrence; kept off topic.
- OpenPham 2025 direction set to help from one triglyceride result; authors call the differences subtle.
- OpenAbioye 2023 studied adults with HIV in Tanzania; its lower death with red meat may not apply widely.
Page history
| Date | Change | Reason |
|---|---|---|
| Nov 14, 2026 | Page created from 54 papers. | First version of the page. |
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