Tumor diseases

Frying, cooking, and grilling of meat and fish produces heterocyclic amines. These substances result from a chemical reaction between the amino acids and the creatine of the muscular substance. Several studies have shown that heterocyclic amines have considerable genotoxic and mutagenic potential. (10, 11)

Heterocyclic amines are a risk factor for several tumor types, in particular for colon carcinoma. In medical literature, also carcinoma of the stomach, esophageal, prostata, pancreas, renal, and mastocarcinoma are brought in connection with heterocyclic amines. (12)

Uruguay and Argentine belong to the countries with the highest consumption of beef and, at the same time, have the highest rate of cancer of the breast and of the colon. Some studies also report a cardiotoxic effect of heterocyclic amines. (13, 14, 15)

Besides heterocyclic amines there are further carcinogen substances which are produced in the intestines by meat consumption. A study by the University of Hohenheim found that a diet high in fat and meat increases the genotoxity of fecal water to the intestinal epithelia. (16)

In microbial protein degradation in the colon, potentially toxic substances develop as a result of protein intake. These include ammonia, phenols, indols, and amines, as well as N nitroso compounds and sulfide. (17)

A study at the University of Cambridge was able to show that there is a close correlation between the formation of N nitroso compounds and the amount of red meat consumed. (18)

It is known that there is an epidemiologic connection between consumption of red meat and the occurrence of colorectal carcinoma. Meat protein also constitutes a significant substrate for bacterial production of sulfide in the intestines. Sulfide compounds moreover contribute to the development of colitides. (19)

Increased concentrations of the insulin-like growth factor I (IGF-1) promote the development of tumor diseases. In 2002 a study of the University of Oxford was published on the IGF concentrations in different diet types. Vegans had significantly lower IGF-1 concentrations than meat-eaters and lacto-ovo vegetarians. In addition, the concentrations of IGF binding proteins (IGFBP-1 and IGFBP-2) were increased in this group. (20)


  1. Sinha R et al: Dietary intake of heterocyclic amines, meat-derived mutagenic activity, and risk of colorectal adenomas; Cancer Epidemiol Biomarkers Prev 2001 May; 10(5): 559-62
  2. Anderson K et al: Meat intake and cooking techniques: associations with pancreatic cancer; Mutat Res 2002 Sep 30; 506-507(C): 225
  3. Matos E et al: Review on meat consumption and cancer in South America; Mutat Res 2002 Sep 30; 506-507(C): 243
  4. Adamson RH et al: Studies on the carcinogenic and myocardial effects of 2-amino-3methylimidazo (4,5-f) quinoline (IQ) in nonhuman primates; Princess Takamatsu Symp 1995; 23: 260-7
  5. Adamson RH et al: Carcinogens in foods: heterocyclic amines and cancer and heart disease; Adv Exp Med Biol 1995; 369: 211-20
  6. Davis CD et al: Protective effect of N-acetylcysteine against heterocyclic amine-induced cardiotoxicity in cultured myocytes and in rats; Food Chem Toxicol 1995 Aug; 33(8): 641-51
  7. Rieger MA et al: A diet high in fat and meat but low in dietary fibre increases the genotoxic potential of „faecal water“; Carcinogenesis 1999 Dec; 20(12): 2311-6
  8. Hughes R et al: Protein degradation in the large intestine: relevance to colorectal cancer; Curr Issues Intest Microbiol 2000 Sept; 1(2): 51-8
  9. Bingham SA et al: Effect of white versus red meat on endogenous N-nitrosation in the human colon and further evidence of a dose response; J Nutr 2002 Nov; 132(11 Suppl): 3522S-3525S
  10. Magee EA et al: Contribution of dietary protein to sulfide production in the large intestine: an in vitro and a controlled feeding study in humans; Am J Clin Nutr 2000 Dec; 72(6): 1488-94
  11. Allen NE et al: The Associations of Diet with Serum Insulin-like Growth Factor and Ist Main Binding Proteins in 292 Woman Meat-Eaters, Vegetarians, and Vegans; Cancer Epidemiol Biomarkers Prev 2002 Nov; 11(11): 1441-8