Estas son algunas investigaciones que muestran la reducción de la incidencia y mortalidad de cánceres de personas vegetarianas con respecto a personas omnívoras (que consumen carnes).        

Elevated Plasma Vitamin B12 Levels as a Marker for Cancer: A Population-Based Cohort Study

Johan Frederik Berg Arendt Lars Pedersen Ebba Nexoand  Henrik Toft Sørensen



Background A substantial proportion of patients referred for plasma vitamin B12 (cobalamin [Cbl]) measurement present with high Cbl levels, which have been reported in patients with different cancer types. However, the cancer risk among patients with newly diagnosed high Cbl levels has not been adequately examined.

Methods We conducted this cohort study using population-based Danish medical registries. Patients referred for Cbl measurement with levels greater than the lower reference limit (≥200 pmol/L) were identified from the population of Northern Denmark during the period of 1998 to 2009 using a database of laboratory test results covering the entire population. Data on cancer incidence (follow-up 1998–2010), Cbl treatment, and prior diagnoses were obtained from medical registries. Patients receiving Cbl treatment were excluded. Cancer risks were calculated as standardized incidence ratios (SIRs) with 95% confidence intervals (CIs), stratified by plasma Cbl levels. All statistical tests were two-sided.

Results We identified 333 667 persons without prevalent cancer and not receiving Cbl treatment. Six percent had Cbl levels greater than the upper reference limit (≥601 pmol/L). Cancer risk increased with higher Cbl levels and was highest during the first year of follow-up (Cbl 601–800 pmol/L: SIR = 3.44, 95% CI = 3.14 to 3.76; Cbl >800 pmol/L: SIR = 6.27, 95% CI = 5.70 to 6.88; both P < .001). The risks were particularly elevated for hematological and smoking- and alcohol-related cancers for persons with high Cbl levels.

Conclusions High Cbl levels were associated with the risk of subsequently diagnosed cancer, mostly within the first year of follow-up. This may have clinical implications for the interpretation of high Cbl levels.

Vitamin B12 (cobalamin [Cbl]) is an essential nutrient involved in one-carbon metabolism and cell division. Daily intake of 2 to 5 μg, together with efficient absorption, transportation, and transformation, are needed to maintain health. In clinical practice, measurement of total plasma Cbl is requested widely for the biochemical assessment of Cbl deficiency. Three studies have shown that a substantial proportion of patients for whom Cbl measurement is requested have plasma Cbl levels greater than the upper limit of the reference range, and two of these studies have shown an association between high Cbl levels and cancer.

The association between elevated plasma Cbl levels and cancer risk is poorly understood. On one hand, a high prevalence of elevated Cbl levels has been reported in patients with liver cancer, other solid tumors, and hematological malignancies. On the other hand, some studies have indicated a high prevalence of cancer, both hematological and solid tumors, among patients with high Cbl levels. However, the latter studies are limited by their cross-sectional design, and only one study included a comparison group of patients with normal and low plasma Cbl levels. Most studies on normal or low Cbl levels in relation to cancer have been negative, except for some studies showing associations between increasing Cbl levels and lung and prostate cancer.

Elevated plasma Cbl levels have also been associated with several nonmalignant diseases, including liver diseases, alcoholism, and renal, autoimmune, and infectious diseases. Only a few patients with these diseases have high Cbl levels. Moreover, these diseases have been reported in a small proportion of patients with high Cbl levels .

To assess the possible clinical implications of elevated Cbl levels in diagnosing cancer, we conducted a population-based cohort study, examining the incidence of cancer diagnoses among patients with elevated plasma Cbl levels.

Low Protein Intake Is Associated with a Major Reduction in IGF-1, Cancer, and Overall Mortality in the 65 and Younger but Not Older Population

Morgan E. Levine, Jorge A. Suarez, Sebastian Brandhorst, Priya Balasubramanian, Chia-Wei Cheng, Federica Madia, Luigi Fontana, Mario G. Mirisola, Jaime Guevara-Aguirre,8 Junxiang Wan, Giuseppe Passarino, Brian K. Kennedy, Min Wei, Pinchas Cohen, Eileen M. Crimmins, and Valter D. Longo.

Fuente: http://www.cell.com/cell-metabolism/abstract/S1550-4131(14)00062-X

Mice and humans with growth hormone receptor/ IGF-1 deficiencies display major reductions in agerelated diseases. Because protein restriction reduces GHR-IGF-1 activity, we examined links between protein intake and mortality. Respondents aged 50–65 reporting high protein intake had a 75% increase in overall mortality and a 4-fold increase in cancer death risk during the following 18 years. These associations were either abolished or attenuated if the proteins were plant derived. Conversely, high protein intake was associated with reduced cancer and overall mortality in respondents over 65, but a 5-fold increase in diabetes mortality across all ages. Mouse studies confirmed the effect of high protein intake and GHR-IGF-1 signaling on the incidence and progression of breast and melanoma tumors, but also the detrimental effects of a low protein diet in the very old. These results suggest that low protein intake during middle age followed by moderate to high protein consumption in old adults may optimize healthspan and longevity.

Es decir, se concluye que el consumo de proteínas animales (carnes rojas, blancas, y todo tipo de animal o producto de origen animal, como el huevo), en forma clásica, en cantidades llamadas normales, aumenta el riesgo de muerte por cánceres, en general, en 4 veces, y en 3 veces por enfermedades en general. El consumo de proteínas de origen vegetal, a diferencia de las de origen animal, o no provoca tal aumento de mortalidad, o directamente evita el riesgo de mortalidad inducida por proteínas de origen animal. 

Con esta análisis investigativo se derrumba uno de los pilares de la nutrición: el del consumo de proteínas animales, las cuales, durante décadas de enseñanza académica, se ha dicho que que era esencial para la salud humana. 

No sólo queda destruido este dogma, sino que además, se ha demostrado que no sólo no son necesarias las proteínas animales, sino que además, el consumo de las mismas aumenta la tasa de mortalidad por cánceres y demás enfermedades, en forma alarmante.

Los investigadores también han concluido que: “We also propose that at older ages, it may be important to avoid low protein intake and gradually adopt a moderate to high protein, preferably mostly plant-based consumption to allow the maintenance of a healthy weight and protection from frailty”, pero de ninguna manera han demostrado que este planteo no esté también asociado a un aumento de las enfermedades citadas, con el consiguiente aumento de la mortalidad, ya que solo hablan de fragilidad, debilidad, interpretándose tal vez, como debilidad muscular. Pero, no obstante, aclaran que lo que recomiendan es que el aumento del consumo de proteinas, debe ser respecto a las de origen vegetal, preferentemente. 

Es muy interesante que también comienza a entenderse que las proteínas no son simples compuestos químicos cuyas propiedades fisiológicas y fisiopatológicas dependen de su secuencia aminoacídica (estructura primaria) y las consecuentes estructuras derivadas de ésta. Se diferencia, algo que ya se había visto en otras investigaciones, diferencias fisiológicas y fisiopatológicas entre las proteínas según su origen sea animal (muscular), lácteas, o vegetales. En esta investigación se observa que las proteínas vegetales tienen un efecto diferente a las de las animales. 

Vegetarianism as a Protective Factor for Colorectal Adenoma and Advanced Adenoma in Asians.

Lee CG, Hahn SJ, Song MK, Lee JK, Kim JH, Lim YJ, Koh MS, Lee JH, Kang HW



Although epidemiologic and animal studies suggest a vegetarian diet protects against the development of colorectal cancer, the relationship between vegetarian diet and incidence of colorectal adenoma is not yet conclusive, especially for Asians.


The purpose of this study was to examine the protective effect of a vegetarian diet against colorectal adenoma and advanced adenoma.


This cross-sectional study compared the prevalence of colorectal adenoma among Buddhist priests, who are obligatory vegetarians, with that among age and sex-matched controls. All the subjects underwent health checkups in a health-promotion center in Korea.


Colorectal adenoma and advanced adenoma were both more prevalent in the general population group than in the Buddhist priest group (25.2 vs. 17.9 %, 6.7 vs. 2.0 %). However, the prevalence of metabolic syndrome, high body mass index, and waist circumference were higher in the Buddhist priest group. According to univariate analysis, non-vegetarian diet (general population) significantly increased the prevalence of colorectal adenoma and advanced adenoma compared with a vegetarian diet (Buddhist priests) (OR 1.54, 95 % CI 1.08-2.21, P = 0.018; OR 3.60, 95 % CI 1.53-8.48, P = 0.003). In a conditional regression analysis model, non-vegetarian diet was also a significant risk factor for colorectal adenoma and advanced adenoma (OR 1.52, 95 % CI 0.75-2.07, P = 0.043; OR 2.94, CI 0.97-7.18, P = 0.036).


Vegetarianism may be effective in preventing both colorectal adenoma and advanced adenoma in Asians.

Dig Dis Sci. 2013 Dec 10.

PMID: 24323183 [PubMed - as supplied by publisher]

Red and processed meat intake and risk of colorectal adenomas: A meta-analysis of observational studies.

Xu X, Yu E, Gao X, Song N, Liu L, Wei X, Zhang W, Fu C.

2012 May 3. doi: 10.1002/ijc.27625.


Department of Colorectal Surgery, Changhai Hospital of Second Military Medical University, Shanghai, China.


Inconsistent results regarding the association between red and processed meat intake and the risk of colorectal adenoma (CRA), the precursor of colorectal cancer (CRC), have been reported. To provide a quantitative assessment of this association, we summarized the evidence from observational studies. Relevant studies were identified in MEDLINE and EMBASE until December 31, 2011. Summary relative risks (SRRs) with 95% confidence intervals (CIs) were pooled with a random-effects model. Between-study heterogeneity was assessed using the Cochran's Q and I(2) statistics. A total of 21 studies (16 case-control studies and five cohort/nested case-control studies) were included in this meta-analysis. The SRRs of CRA were 1.36 (95% CI = 1.17-1.58) for every 100 g/day increase in red meat intake, and 1.24 (95% CI = 1.12-1.36) for the highest versus the lowest level of red meat intake. Nonlinear dose-response meta-analysis indicated that CRA risk increased approximately linearly with increasing intake of red meat up to ∼ 90 g/day, where the curve reached its plateau. Subgrouped analyses revealed that the increased risk of CRA with intake of red meat was independent of geographic locations, design and confounders. The SRRs of CRA was 1.28 (95% CI = 1.03-1.60) for per 50 g/day increase in processed meat intake, and 1.17 (95% CI = 1.08-1.26) for the highest versus the lowest level of processed meat intake. Increased intake of red and processed meat is associated with significantly increased risk of CRA.
Copyright © 2012 UICC.

Fuente: http://www.ncbi.nlm.nih.gov/pubmed/22553166

En este análisis estadístico, de una gran cantidad de investigaciones a nivel internacional, se confirma algo que hace muchos años se comenzó a evidenciar: la evidente disminución, en vegetarianos, con respeto a omnívoros (quienes comen carnes) de la muerte por enfermedades cardiovasculares, junto con la disminución evidente de la incidencia de otra terrible enfermedad, el cáncer.

Con este trabajo se demuestra que la gran mayoría de las investigaciones, durante muchos años, en conjunto, han comprobado que estas dos enfermedades, las cuales están entre las principales causas de muerte en ciudades en el mundo (en Argentina las enfermedades cardiovasculares y ciertos cánceres, son las prinicipales causas de muerte por enfermedades) pueden ser disminuidas, en cuanto a incidencia, y como consecuencia a ello, su resultado mortal, al adoptar una dieta vegetariana.

Cardiovascular disease mortality and cancer incidence in vegetarians: a meta-analysis and systematic review.

Huang T, Yang B, Zheng J, Li G, Wahlqvist ML, Li D.

Source: Department of Food Science and Nutrition, Zhejiang University, Hangzhou, China.



Prospective cohort studies have examined mortality and overall cancer incidence among vegetarians, but the results have been inconclusive.


The objective of the present meta-analysis was to investigate cardiovascular disease mortality and cancer incidence among vegetarians and nonvegetarians.


Medline, EMBASE and Web Of Science databases were searched for cohort studies published from inception to September 2011. Studies were included if they contained the relative risk (RR) and corresponding 95% CI. Participants were from the UK, Germany, California, USA, the Netherlands and Japan.


Seven studies with a total of 124,706 participants were included in this analysis. All-cause mortality in vegetarians was 9% lower than in nonvegetarians (RR = 0.91; 95% CI, 0.66-1.16). The mortality from ischemic heart disease was significantly lower in vegetarians than in nonvegetarians (RR = 0.71; 95% CI, 0.56-0.87). We observed a 16% lower mortality from circulatory diseases (RR = 0.84; 95% CI, 0.54-1.14) and a 12% lower mortality from cerebrovascular disease (RR = 0.88; 95% CI, 0.70-1.06) in vegetarians compared with nonvegetarians. Vegetarians had a significantly lower cancer incidence than nonvegetarians (RR = 0.82; 95% CI, 0.67-0.97).


Our results suggest that vegetarians have a significantly lower ischemic heart disease mortality (29%) and overall cancer incidence (18%) than nonvegetarians.

Copyright © 2012 S. Karger AG, Basel.
PMID: 22677895 [PubMed - indexed for MEDLINE]

En este nuevo análisis se mantiene la tendencia de conclusiones, respecto a la actividad protectiva y anticancerígena de las dietas vegetarianas (incluyendo la vegana).

Es más que evidente, ya pasado más de 10 años de investigaciones, que las dietas vegetarianas son protectoras de la mayor parte de los cánceres, e inversamente, las carnes, son mas o menos inductoras, según el tipo de cáncer, pero nunca son protectoras.

2012 Nov 20. [Epub ahead of print]


Tantamango-Bartley Y, Jaceldo-Siegl K, Fan J, Fraser G.




Cancer is the second leading cause of death in the US. Dietary factors account for at least 30% of all cancers in Western countries. Since people do not consume individual foods but rather combinations of them, the assessment of dietary patterns may offer valuable information when determining associations between diet and cancer risk.


We examined the association between dietary patterns (non-vegetarians, lacto, pesco, vegan, and semi-vegetarian) and the overall cancer incidence among 69,120 participants of the Adventist Health Study-2. Cancer cases were identified by matching to cancer registries. Cox-proportional hazard regression analysis was performed to estimate hazard ratios, with "attained age" as the time variable.


2,939 incident cancer cases were identified. The multivariate HR of overall cancer risk among vegetarians compared to non-vegetarians was statistically significant (HR=0.92; 95%CI: 0.85, 0.99) for both genders combined. Also, a statistically significant association was found between vegetarian diet and cancers of the gastrointestinal tract (HR=0.76; 95%CI: 0.63, 0.90). When analyzing the association of specific vegetarian dietary patterns, vegan diets showed statistically significant protection for overall cancer incidence (HR=0.84; 95%CI: 0.72, 0.99) in both genders combined and for female-specific cancers (HR=0.66; 95%CI: 0.47, 0.92). Lacto-ovo-vegetarians appeared to be associated with decreased risk of cancers of the gastrointestinal system (HR=0.75; 95%CI: 0.60, 0.92).


Vegetarian diets seem to confer protection against cancer. Impact: Vegan diet seems to confer lower risk for overall and female-specific cancer compared to other dietary patterns. The lacto-ovo-vegetarian diets seem to confer protection from cancers of the gastrointestinal tract.
PMID:23169929 [PubMed - as supplied by publisher]

En esta investigación se mantiene la tendencia: consumo de carnes y grasas totales aumenta el riesgo de cáncer de cólon y de recto, e inversamente, el consumo de vegetales disminuye dicho riesgo.

En este estudio, incluso, se ha observado la relación entre lo dicho y la edad. Cuando se adelanta la tendencia al cambio de dieta, a favor de disminuir el consumo de carnes rojas y aumentar el consumo de vegetales en temprana edad, disminuye también el riesgo del desarrollo de los cánceres citados.

Adolescent and mid-life diet: risk of colorectal cancer in the NIH-AARP Diet and Health Study.

Ruder EH, Thiébaut AC, Thompson FE, Potischman N, Subar AF, Park Y, Graubard BI, Hollenbeck AR, Cross AJ.

Source: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Department of Health and Human Services, Rockville, MD, USA. rudereh@mail.nih.gov


BACKGROUND: Colorectal cancer has a natural history of several decades; therefore, the diet consumed decades before diagnosis may aid in understanding this malignancy.

OBJECTIVE: The objective was to investigate diet during adolescence and 10 y before baseline (ages 40-61 y) in relation to colorectal cancer.

DESIGN: Participants in the NIH-AARP Diet and Health Study (n = 292,797) completed a 124-item food-frequency questionnaire (FFQ) about diet in the past 12 mo and two 37-item FFQs about diet at ages 12-13 y and 10 y previously. Cox regression was used to estimate multivariate HRs and 95% CIs for colon (n = 2794) and rectal (n = 979) cancers within quintiles of exposures.

RESULTS: Colon cancer risk was lower in the highest than in the lowest quintile of vitamin A (HR: 0.82; 95% CI: 0.72, 0.92) and vegetable (HR: 0.81, 0.70, 0.92) intakes during adolescence. Those in the highest intake category 10 y previously for calcium (HR: 0.83; 95% CI: 0.73, 0.94), vitamin A (HR: 0.81; 95% CI: 0.71, 0.92), vitamin C (HR: 0.83; 95% CI: 0.72, 0.95), fruit (HR: 0.84; 95% CI: 0.73, 0.97), and milk (HR: 0.78; 95% CI: 0.67, 0.90) had a lower risk of colon cancer, but a higher risk was observed for total fat (HR: 1.15; 95% CI: 1.01, 1.30), red meat (HR: 1.31; 95% CI: 1.12, 1.53), and processed meat (HR: 1.24; 95% CI: 1.06, 1.45). For rectal cancer, milk was inversely associated (HR: 0.75; 95% CI: 0.58, 0.96) with risk.

CONCLUSION: Adolescent and midlife diet may play a role in colorectal carcinogenesis.

PMID:22071715[PubMed - indexed for MEDLINE] PMCID:PMC3252554[Available on 2012/12/1]


Hace muchos años que se está analizando cuales son los componentes de la carne que actúan como inductores. Entre ellos está el hierro hemínico de la hemoglobina y de la mioglobina, y ciertos compuestos químicos, llamados N-nitroso, que poseen un alto poder de genotoxicidad (toxicidad a nivel genómico). En un estudio realizado por integrantes del Departamento de Toxicogenómicos, de la Universidad de Maastricht, Holanda, en este año 2011, investigaron el efecto del consumo de carnes rojas, durante 7 días, en humanos. Observaron, coherentemente con muchos otros trabajos de investigación, el aumento de la genotoxicidad colónica, en función del consumo de carnes rojas, evidenciado con alteraciones en la expresión genómica, las que normalmente están implicadas en el cáncer colorectal.
2012 Feb;50(2):95-103. doi: 10.1016/j.fct.2011.10.038. Epub 2011 Oct 14.

Red meat intake-induced increases in fecal water genotoxicity correlate with pro-carcinogenic gene expression changes in the human colon.


Department of Toxicogenomics, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands. d.hebels@maastrichtuniversity.nl


Red meat consumption is associated with an increased colorectal cancer (CRC) risk, which may be due to an increased endogenous formation of genotoxic N-nitroso compounds (NOCs). To assess the impact of red meat consumption on potential risk factors of CRC, we investigated the effect of a 7-day dietary red meat intervention in human subjects on endogenous NOC formation and fecal water genotoxicity in relation to genome-wide transcriptomic changes induced in colonic tissue. The intervention showed no effect on fecal NOC excretion but fecal water genotoxicity significantly increased in response to red meat intake. Colonic inflammation caused by inflammatory bowel disease, which has been suggested to stimulate endogenous nitrosation, did not influence fecal NOC excretion or fecal water genotoxicity. Transcriptomic analyses revealed that genes significantly correlating with the increase in fecal water genotoxicity were involved in biological pathways indicative of genotoxic effects, including modifications in DNA damage repair, cell cycle, and apoptosis pathways. Moreover, WNT signaling and nucleosome remodeling pathways were modulated which are implicated in human CRC development. We conclude that the gene expression changes identified in this study corroborate the genotoxic potential of diets high in red meat and point towards a potentially increased CRC risk in humans.
Copyright © 2011 Elsevier Ltd. All rights reserved.
[PubMed - indexed for MEDLINE]

Consumption of Food Groups and the Risk of Pancreatic Cancer: A Case-Control Study.Ghadirian P, Nkondjock A.
Epidemiology Research Unit, Research Centre, Centre Hospitalier de l'Université de Montréal (CRCHUM)-Hôtel-Dieu, Faculty of Medicine, Université de Montréal, 3850 St. Urbain St., Montreal, H2W 1T7, QC, Canada,

PURPOSE: The purpose of this study is to investigate whether the consumption of specific food groups predicts the risk of pancreatic cancer, a case-control study of nutrition and pancreatic cancer among French-Canadians was carried out in Montreal, Quebec, Canada. METHODS: A total of 179 pancreatic cancer cases (97 males and 82 females) and 239 population-based control subjects were interviewed. Dietary intake was evaluated via a validated food frequency questionnaire that gathers information on over 200 different food items and beverages. Odd ratios (ORs) and 95% confidence intervals (CIs) were computed by unconditional logistic regression. RESULTS: After adjustment for age, smoking, diabetes status, proxy interview, gender and total energy intake, a reduced risk of pancreatic cancer was related to vegetables and vegetable products [OR = 0.47; 95%CI: (0.21-1.06) p-trend = 0.024], while an increased risk was associated with the consumption of lamb, veal and game [OR = 2.24; 95%CI: (1.11-4.52) p-trend = 0.026], when the upper and lower quartiles of intake were compared. Changes in dietary intake over the last decade revealed an elevated risk with augmented consumption of soups, sauces and gravies [OR = 2.32; 95%CI: (1.20-4.49) p-trend=0.03], beef products [OR = 2.07; 95%CI: (0.95-4.51) p-trend=0.05] as well as fish and shellfish [OR = 1.48; 95%CI: (0.78-2.80) p-trend=0.05]. CONCLUSIONS: These findings suggest that a diet rich in vegetables and vegetable products may decrease the risk of pancreatic cancer.

PMID: 20101477 [PubMed - as supplied by publisher]


El objetivo de este estudio es investigar si el consumo especifico de determinados grupos de alimentos predice el riesgo de cáncer pancreático. Un estudio de caso - control de nutrición y cáncer pancreático entre canadienses franceses fue llevado a cabo en Montreal, Quebec, Canadá. Método: un total de 179 casos de cáncer pancreático (97 hombres y 82 mujeres) y 239 sujetos de la población tomados como control, fueron interrogados. La dieta fue evaluada vía un cuestionario de frecuencias alimenticias validado dentro de 200 items opcionales de alimentos. Los odd ratios (relación probabilística de hechos) y los intervalos de confidencia del 95% (CIs) fueron computarizados a través de una regresión logística incondicional.

Resultados: después de hacer ajustes por edad, fumadores, diabetes, género y consumo de energía total, una reducción del riesgo de cáncer pancreático fue relacionada al consumo de vegetales y productos vegetales [(OR= 0.47, CI: 0.21-1.06) p-trend = 0.024], mientras un incremento del riesgo fue asociado al consumo de carne de cordero, vaca y aves [OR = 2.24; 95%CI: (1.11-4.52) p-trend = 0.026], cuando los cuartilos mayor y menor de consumo fueron comparados. Cambios en el consumo de alimentos en la última década demuestran un riesgo elevado de cáncer pancréatico con el consumo de salsas picantes, caldos y salsas a base de carnes [OR = 2.32; 95%CI: (1.20-4.49) p-trend=0.03], productos derivados de la carne [OR = 2.07; 95%CI: (0.95-4.51) p-trend=0.05], así como de pescado y mariscos [OR = 1.48; 95%CI: (0.78-2.80) p-trend=0.05].
Conclusiones: estos resultados sugieren que las dietas ricas en vegetales y productos vegetales pueden reducir el riesgo de cáncer pancreático.

Esta es otra investigación con resultados coherentes con la tendencia actual de confirmar que las dietas vegetarianas son preventivas de ciertos cánceres, en este caso particular, el agresivísimo cáncer pancreático.