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Query: UMLS:C0699790 (colon cancer)
 28,837 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It has been postulated that dietary fiber's protective effect against the development of colon cancer, diverticular disease, and atherosclerosis may be due to the adsorption and/or dilution of intestinal sterols such as bile acids and neural sterols and their bacterial metabolites by component(s) of fiber. Dietary fiber is made up of four major components-cellulose, hemicellulose, lignin, and pectin. There is evidence that hemicellulose and pectin may induce an increase in fecal bile acid excretion in man which may be accompanied by a decrease in serum cholesterol. Natural fibers, such as rolled oats, alfalfa, guar gum, and Bengal gram have been shown to have hypocholesterolemic properties of alfalfa, wheat straw, and some other fibers found considerable amounts of bile acids in vitro. On the other hand, wheat bran, oat hulls, and all the synthetic fibers tested bound only negligible amounts of bile acids under the same conditions. Vegetarians in the United States have lower plasma lipids and different plasma lipoprotein patterns than those of comparable control populations on regular mixed diet. They also have smaller daily fractional turnover rates of cholic acid and deoxycholic acid pool size. In addition, populations on a mixed Western diet, where the rate of large bowel cancer is high (North American, English, Scottish, etc.) degraded and excreted cholesterol and bile acid metabolites to a greater degree than populations where the rate of colon cancer is comparatively low (Ugandan, Japanese, etc). It cannot be denied that the fiber theory linking fiber deficiency with the development of colon cancer and other diseases, is simple, attractive and appears to be firmly based in common sense. When subjected to research studies, however, the situation appears much more complex than expected. Although some progress is being made, the data are often contradictory and confusing, probably due to lack of adequate documentation of fiber intake (e.g., use of dietary fiber instead of crude fiber) and/or the absence of detailed information on the chemistry of the fiber itself.
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PMID:Fiber, intestinal sterols, and colon cancer. 34 68

The intimal thickening of arteries present in 95 resected specimens of carcinoma of the colon was studied, using sections from the tumour area and from adjacent normal bowel. Arteries from the tumour area showed a very significant increase in intimal thickening as compared with the controls. It is suggested that the local factor associated with the tumour area is an impaired drainage of macromolecules from the intimal compartment of the arteries due to obstruction of the lymphatic channels of the surrounding interstitial tissue by tumour cells and fibrosis.
Atherosclerosis 1979 Apr
PMID:The arterial wall in malignant disease. 46 24

Recent theories have postulated that low fiber diets are related to colon cancer and diverticulosis, and to atherosclerosis. These theories are based on British and African diet history information. There has been no recent assessment of fiber intake in an area of high incidence of colonic disease in the United States. Using recall diet histories in subjects with no disease and with colon disease, and correcting our data to account for any loss in recall history, we find a low daily fiber intake in all 21 subjects evaluated, mean 3.5 g, range 1.6 to 11 g. There was no statistical difference in intake among patients with or without colon disease. The data agree with the British findings. Since the incidence of the diseases in question is not uniform in the United States it is suggested that diet surveys are needed in areas where colon carcinoma is of low incidence.
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PMID:Low fiber content of Connecticut diets. 124 80

This review of corn oil provides a scientific assessment of the current knowledge of its contribution to the American diet. Refined corn oil is composed of 99% triacylglycerols with polyunsaturated fatty acid (PUFA) 59%, monounsaturated fatty acid 24%, and saturated fatty acid (SFA) 13%. The PUFA is linoleic acid (C18:2n-6) primarily, with a small amount of linolenic acid (C18:3n-3) giving a n-6/n-3 ratio of 83. Corn oil contains a significant amount of ubiquinone and high amounts of alpha- and gamma-tocopherols (vitamin E) that protect it from oxidative rancidity. It has good sensory qualities for use as a salad and cooking oil. Corn oil is highly digestible and provides energy and essential fatty acids (EFA). Linoleic acid is a dietary essential that is necessary for integrity of the skin, cell membranes, the immune system, and for synthesis of icosanoids. Icosanoids are necessary for reproductive, cardiovascular, renal, and gastrointestinal functions and resistance to disease. Corn oil is a highly effective food oil for lowering serum cholesterol. Because of its low content of SFAs which raises cholesterol and its high content of PUFAs which lowers cholesterol, consumption of corn oil can replace SFAs with PUFAs, and the combination is more effective in lowering cholesterol than simple reduction of SFA. PUFA primarily lowers low-density-lipoprotein cholesterol (LDL-C) which is atherogenic. Research shows that PUFA has little effect on high-density-lipoprotein cholesterol (HDL-C) which is protective against atherosclerosis. PUFA generally improves the ratio of LDL-C to HDL-C. Studies in animals show that PUFA is required for the growth of cancers; the amount required is considered to be greater than that which satisfies the EFA requirement of the host. At this time there is no indication from epidemiological studies that PUFA intake is associated with increased risk of breast or colon cancer, which have been suggested to be promoted by high-fat diets in humans. Recommendations for minimum PUFA intake to prevent gross EFA deficiency are about 3% of energy (en%). Recommendations for prevention of heart disease are 8-10 en%. Consumption of PUFA in the United States is 5-7 en%. The use of corn oil to contribute to a PUFA intake of 10 en% in the diet would be beneficial to heart health. No single source of salad or cooking oil provides an optimum fatty acid (FA) composition. Many questions remain to be answered about the relation of FA composition of the diet to various physiological functions and disease processes.
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PMID:Food uses and health effects of corn oil. 225 33

Genetic factors play an important role in the development of many common diseases of adulthood that result in early morbidity and mortality. Prevention of these disorders and their sequelae is best established through early detection and early intervention. Although it may be feasible to screen the entire population for some disorders (e.g., hypertension), this approach would be expensive and impractical for others (e.g., colon cancer). The family history provides an inexpensive and convenient method of identifying families at risk for premature diseases of adulthood. Family screening for a disorder should be recommended if there is increased risk for the disorder among family members, if screening methods are available to detect the condition at an early age or preclinical stage, and if early intervention will alter the course of the disease. For many disorders screening and intervention can prevent the occurrence of clinical disease. The prenatal counseling session affords an ideal setting for identifying families at risk for diseases of adulthood with major genetic components. By reviewing the family history, key family members can be identified and investigated, in order to establish a specific genetic diagnosis. At-risk relatives can then be counseled and screened for the disorder preclinically and premorbidly. The screening and intervention available for a disease depends on the nature of the disorder, our understanding of its physiology and etiology, and our current technology. The disorders discussed earlier are typical of conditions of adulthood that are influenced strongly by genetic factors, especially when they appear in younger adults. Atherosclerosis, colon cancer, and diabetes are complex phenotypes. Each can be caused by single-gene defects, but commonly the genetics are more complex. Empiric data help to establish the risk to an individual in the latter cases. In all three examples, early detection should lead to treatment, which can prevent more serious sequelae: by treating the dyslipidemia, coronary artery disease can be prevented; by removing the benign polyp, malignant cancer can be avoided; and when impaired glucose tolerance is detected, diet and exercise can prevent or delay frank diabetes and its complications. The complete evaluation of individuals at risk for disorders such as those in Table 1 and their families can be a complicated task. Referral to a center experienced in the genetics of common diseases often may be necessary.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Genetics of common diseases of adulthood. Implications for prenatal counseling and diagnosis. 228 33

Dietary fiber has been, for several years, the glamour ingredient in popular nutrition. Based on epidemiological evidence, lack of fiber in the diet has been impugned as a major risk factor for development of colon cancer, heart disease, diabetes and a variety of lesser ills. Animal experiments suggest that some components of the complex mixture of substances called fiber will reduce cholesterol levels to a modest extent and will inhibit atherosclerosis induced by diet. In man the data center on the effects of fiber on plasma cholesterol levels and some fibers such as pectin or guar exert significant hypocholesterolemic effects whereas others, such as bran, do not. The situation is similar with regard to colon cancer. Some types of fiber, bran and cellulose for instance, inhibit experimentally induced colon cancer. There are a number of ways of establishing experimental colon cancer; feeding the carcinogenic agent, injecting it, or instilling it intrarectally. There also exists a variety of carcinogenic agents. The effect of fiber is the sum of the type of fiber and carcinogen used and the mode of establishing the cancer. Different combinations give different results in animal studies. In man the data bearing on this subject are wholly epidemiological. A few case-control studies have provided suggestions that low fiber diets may predispose to colon cancer but these studies point to a dietary life-style in which many components other than fiber vary. The most notable success in wedding practice to hypothesis has been in the area of diabetes. Here it has been shown clearly that increasing dietary fiber results in reductions in lipemia, glycemia and insulin requirement. What remains? More work in the cancer and heart disease fields but mainly a greater effort to identify the specific structure of those fibers which exert a beneficial effect. This will have the two-fold benefit of identification of specifically useful structural types of fiber and of possibly providing clues to mechanism of action or of carcinogenicity. Most experts agree that a modest increase in intake of fiber will have a generally beneficial effect but they can only support these statements with epidemiological proof. Future research must include studies designed to confirm the epidemiological findings and to identify the specific components responsible for them.
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PMID:The role of dietary fiber in health and disease. 301 64

It is generally accepted that most colorectal cancers arise from adenomatous polyps and most coronary heart disease is caused by severe atherosclerosis. In order to compare the frequency of these disease precursors in men of Japanese ancestry in Hawaii, the degree of atherosclerosis of the aorta and coronary arteries was estimated by the panel method in 288 male autopsy subjects. The extent of atherosclerosis was then compared in men who did or did not have adenomatous polyps as determined at autopsy. The degree of atherosclerosis of the coronary arteries and aorta was positively and significantly related not only to the presence of adenomatous polyps, but to their size, multiplicity, and degree of atypia as well. This study suggests that shared environmental events could account for the development of severe atherosclerosis and adenomatous polyps. At the same time, it has been observed that hawaii Japanese men experience colon and rectal cancer rates higher than those of US Whites, but their coronary heart disease (CHD) rates are intermediate between the low rates of Japan and the high rates of the US white population. These differences in disease trends and differences in the serum cholesterol and fat intake of Hawaii Japanese men with CHD and colon cancer have suggested that men with these diseases represent different subsets of the westernized Japanese population. If CHD and colon cancer occur in different subsets of this population, they must stem from the accumulation of other risk factors superimposed upon the initiators of their precursor lesions.
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PMID:Adenomatous polyps and atherosclerosis: an autopsy study of Japanese men in Hawaii. 379 59

The prevalence of adenomatous and hyperplastic polyps of the colon and the degree of involvement of the aorta by atherosclerotic lesions were evaluated in 842 autopsies from New Orleans. A positive statistical association between the two variables was found in white males under 75 years of age. In black males a positive correlation between atherosclerotic lesions and adenomatous (but not hyperplastic) polyps was found. The most extensive involvement of the aorta by atherosclerosis was found in patients in whom adenomatous and hyperplastic polyps coincided. The possibilities that dietary factors may account for these findings and its relevance in relation to colon cancer and coronary heart disease are discussed.
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PMID:Atherosclerosis and polyps of the colon. Quantification of precursors of coronary heart disease and colon cancer. 706 7

Most animal and human studies show that phytosterols reduce serum/or plasma total cholesterol and low density lipoprotein (LDL) cholesterol levels. Phytosterols are structurally very similar to cholesterol except that they always contain some substitutions at the C24 position on the sterol side chain. Plasma phytosterol levels in mammalian tissue are normally very low due primarily to poor absorption from the intestine and faster excretion from liver compared to cholesterol. Phytosterols are able to be metabolized in the liver into C21 bile acids via liver other than normal C24 bile acids in mammals. It is generally assumed that cholesterol reduction results directly from inhibition of cholesterol absorption through displacement of cholesterol from micelles. Structure-specific effects of individual phytosterol constituents have recently been shown where saturated phytosterols are more efficient compared to unsaturated compounds in reducing cholesterol levels. In addition, phytosterols produce a wide spectrum of therapeutic effects in animals including anti-tumour properties. Phytosterols have been shown experimentally to inhibit colon cancer development. With regard to toxicity, no obvious side effects of phytosterol have been observed in studies to date, except in individual with phytosterolemia, an inherited lipid disorder. Further characterization of the influence of various phytosterol subcomponents on lipoprotein profiles in humans is required to maximize the usefulness of this non-pharmacological approach to reduction of atherosclerosis in the population.
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PMID:Dietary phytosterols: a review of metabolism, benefits and side effects. 759 26

A mortality cohort study was carried out on 2,291 workers, including 169 women, with chronic occupational CS2 poisoning diagnosed during the years 1970-90. Information on vital status was available for 98.2% as of December 31, 1992. Mortality assessment was based on the standardized mortality ratio using the person-years method. The general population of Poland was the reference population. The number of subjects who died during the period of observation accounted for 658 men and 21 women. The analysis of mortality in male subjects showed statistically significant excess of deaths from the circulatory system diseases (SMR = 139), in this from ischaemic heart disease (SMR = 137), cerebrovascular disease (SMR = 188) and colon cancer (SMR = 233). Over a two-fold increased risk of death from diseases of the nervous system and sense organs, although statistically insignificant, was also observed. Among women a statistically significant risk of death from atherosclerosis was noted (SMR = 286). An elevated risk of death from the circulatory system diseases and from ischaemic disease (IHD) agrees with the results of some other cohort studies carried out in the viscose rayon workers. The increased mortality from malignant neoplasms is an unusual finding in cohorts of workers exposed to CS2. Our own data reported here showed a significantly increased mortality from colon cancer (9 cases). All these cases were noted in workers of the two oldest rayon plants and they require a detailed analysis. Further survey is also needed to elucidate the excess of deaths from the nervous system and sense organs diseases.
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PMID:A mortality study of workers with reported chronic occupational carbon disulfide poisoning. 911 88


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