ascorbic-acid and Intestinal-Neoplasms

Gastrointestinal cancers, mainly oesophageal, gastric, pancreatic and large bowel cancer, account for about 40,000 deaths annually in England and Wales which is 32% of all cancer deaths. Nutritional factors have been implicated in the cause of each cancer and probably act by promoting the effect of carcinogenic substances taken in the diet or produced in the gut. Gastric cancer for example may be due to nitrosamine production in the stomach. This is enhanced by readily available sources of dietary nitrite and nitrate whilst the reaction is inhibited by vitamin C and low temperatures (2 degrees C). By contrast large bowel cancer can be related to high fat and meat intakes whilst a protective role for dietary fibre has been suggested. Dietary factors in the aetiology of oesophageal cancer differ from one high incidence area to another.

Topics: Animals; Ascorbic Acid; Cold Temperature; Diet; Dietary Fats; Dietary Fiber; Digestive System; Esophageal Neoplasms; Gastrointestinal Motility; Gastrointestinal Neoplasms; Humans; Intestinal Neoplasms; Meat; Nitrosamines; Organ Specificity; Pancreatic Neoplasms; Stomach Neoplasms

In spite of diverging incidence trends, subsite, and subtype-specific gastric cancer data on the association with dietary antioxidants are sparse. We aimed to test whether the apparent protective effect of antioxidants is mainly confined to noncardia (distal) cancer of the intestinal subtype, to which most of the incidence decline in gastric cancer has been ascribed. In a Swedish study base (total population 1.3 million), we interviewed 567 cases uniformly classified to subsite (cardia vs. noncardia) and subtype (intestinal vs. diffuse), and 1165 population-based controls, frequency matched for age and sex. Serologic data on H. pylori status was available for a subset of 542 individuals. Ascorbic acid (vitamin C) was inversely associated with all subsites and subtypes of gastric cancer in a significant dose-response manner (all p<0.05), with risk reductions between 40% and 60%. beta-carotene was also strongly and negatively associated with risk, particularly with the intestinal type. The associations with alpha-tocopherol (vitamin E) were less clear. The highest parallel intake of all three antioxidants (quartiles 4), compared to those with the lowest parallel intakes (quartiles 1), was associated with a 70% lower risk of developing noncardia cancer (OR 0.3, 95% CI 0.1-0.9). Our results suggest that antioxidants might be especially beneficial among subjects at increased risk for gastric cancer such as smokers and those infected by H. pylori. We conclude that a high intake of antioxidants, as a consequence of high consumption of fruit and vegetables, may lower the risk not only for gastric cancer of the intestinal type, but also for diffuse type adenocarcinoma and cardia cancer.

Topics: Adenocarcinoma; Adult; Aged; Antioxidants; Ascorbic Acid; beta Carotene; Cardia; Case-Control Studies; Female; Fruit; Helicobacter pylori; Humans; Intestinal Neoplasms; Male; Middle Aged; Odds Ratio; Risk Factors; Smoking; Stomach Neoplasms; Sweden; Vegetables; Vitamin E

Male Sprague-Dawley rats were fed a diet containing either 0.005% beta-carotene, 0.02% sodium ascorbate or 1.5% cellulose for 14 weeks. Beginning on day 3, all animals were also given weekly subcutaneous injections of 1,2-dimethylhydrazine (DMH; 20 mg/kg body wt.) throughout a 12-week period. The experimental diet was continued for an additional 14 weeks. At the end of the 26th week, surviving animals were sacrificed and the incidence of intestinal carcinomas was examined. A significantly lower incidence of carcinomas was observed in the beta-carotene-fed group (55.0%), compared with that in the control group given DMH (82.1%).

Topics: 1,2-Dimethylhydrazine; Animals; Anticarcinogenic Agents; Ascorbic Acid; beta Carotene; Body Weight; Carotenoids; Cellulose; Dimethylhydrazines; Intestinal Neoplasms; Male; Rats; Rats, Sprague-Dawley

Topics: Adult; Alcoholism; Ascorbic Acid; Esophageal Neoplasms; Female; Gastrointestinal Neoplasms; Humans; Intestinal Neoplasms; Male; Middle Aged; Nutritional Physiological Phenomena; Risk Factors; Stomach Neoplasms

Topics: Acidosis; Adult; Aged; Ascorbic Acid; Female; Glucose; Humans; Insulin; Intestinal Neoplasms; Lung Neoplasms; Male; Middle Aged; Ovarian Neoplasms; Premedication; Pyridoxine; Stomach Neoplasms; Thiamine; Thiamine Pyrophosphate; Uterine Neoplasms

This series presents further evidence for an association between reticulosis of the intestine and steatorrhoea. Although some patients have a definite past history of gluten enteropathy, it seems likely that in certain patients the reticulosis itself is the primary cause of the steatorrhoea.

Topics: Ascorbic Acid; Blood Transfusion; Body Weight; Bone Marrow Examination; Celiac Disease; Diet; Diet Therapy; Fats; Feces; Folic Acid; Humans; Intestinal Neoplasms; Intestinal Perforation; Intestine, Small; Iron; Lymphoma, Large B-Cell, Diffuse; Lymphoma, Non-Hodgkin; Nandrolone; Neomycin; Neoplasms; Pathology; Prednisone; Sarcoma; Steatorrhea; Surgical Procedures, Operative; Vitamin A; Vitamin B 12; Vitamin B Complex; Vitamins; Water-Electrolyte Balance

Topics: Ascorbic Acid; Carcinogens; Citrus; Dietary Fats; Fruit; Humans; Intestinal Neoplasms; Neoplasms; Netherlands; Nutrition Surveys; Nutritional Status; Stomach Neoplasms