ABSTRACT
OBJECTIVE: Diet is an area of major interest to those investigating the causes of cancer of the oesophagus in the Transkei. This study looked at the associations between intragastric epidermal growth factor level, diet and intragastric pH. SETTING AND SUBJECTS: A dietary survey was co-ordinated with studies of gastric luminal epidermal growth factor and gastric fluid pH in 120 rural Transkeians. RESULTS: Gastric fluid epidermal growth factor was associated with low dietary intake of animal products (p = 0.002) and vegetables (p = 0.026). There was no association with pH. CONCLUSION: A dietary subgroup has been identified in the Transkei population with high levels of epidermal growth factor in the upper gastrointestinal lumen. This adds to previously demonstrated diet-related changes in the upper gastrointestinal tract in Transkei. These changes may affect the disease pattern of the population.
Subject(s)
Diet/adverse effects , Epidermal Growth Factor/analysis , Esophageal Neoplasms/etiology , Gastric Juice/chemistry , Gastric Mucosa/chemistry , Cocarcinogenesis , Dairy Products , Diet Surveys , Epidermal Growth Factor/physiology , Esophageal Neoplasms/epidemiology , Fruit , Gastric Acidity Determination , Gastric Juice/physiology , Gastric Mucosa/physiology , Humans , Hydrogen-Ion Concentration , Meat , Metabolic Clearance Rate , Pepsin A/physiology , Poverty/statistics & numerical data , Radioimmunoassay , Rural Health/statistics & numerical data , South Africa/epidemiology , Surveys and Questionnaires , VegetablesABSTRACT
SETTING: The people of Transkei eat a diet high in linoleic acid, the principal fatty acid in maize. The theory has been put forward that a diet high in linoleic acid and low in fat and riboflavin, such as the traditional diet in Transkei, results in overproduction of prostaglandin E2 in the gastric mucosa, and that this overproduction in turn causes a suppression of gastric acid production. OBJECTIVE: To investigate the effect of diet on fasting gastric pH in a rural black African population. DESIGN: Fasting gastric acid samples were obtained by fine nasogastric tube aspiration from 150 volunteers at a rural health clinic. The pH of these samples was measured and a full dietary questionnaire was used. Helicobacter pylori serology was done on a subgroup of 30 volunteers. RESULTS AND CONCLUSIONS: A bimodal pH distribution was found. Approximately half the population had a gastric pH within the range 1-4. Half had a pH of over 4. A high pH was significantly associated with consumption of maize (p = 0.006), and with consumption of both pumpkin and beans (p = 0.006). A high proportion of this rural African population has a diet-associated abnormally high gastric pH. The pattern of upper gastrointestinal disease may be significantly affected by diet in this community and in others with a similar diet.
