Gastric luminal epidermal growth factor is affected by diet.

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.     

Faecal pH value and its modification by dietary means in South African black and white schoolchildren.

Mean faecal pH values did not differ significantly in groups of rural South African Black schoolchildren of 10--12 years who ate their traditional high-fibre low-fat diet, and urban dwellers who consumed a partially westernized diet. However, both means were significantly lower than those of groups of White schoolchildren. In feeding studies of 5 days' duration, mean faecal pH value of Black children became significantly less acid when white bread replaced maize meal, and became significantly more acid when a supplement of 6 oranges was consumed daily. Supplements which consisted of skim milk, butter, and sugar had no significant effect on mean faecal pH value. In White children in an institution, the mean pH value of faeces became significantly more acid when a supplement of 6 oranges, although not of bran 'crunchies', was consumed daily.     

Dyspepsia and gastric emptying in chronic renal failure patients.

AIMS: Chronic renal failure (CRF) patients frequently suffer from dyspeptic complaints such as nausea, vomiting, abdominal distension, early satiety and anorexia. The aim of the present study was to define the prevalence of dyspeptic complaints and delayed gastric emptying in CRF patients. MATERIAL AND METHODS: Dyspeptic complaints were assessed anamnestically in 62 non-dialyzed CRF patients. Gastric emptying for solids was evaluated by the 13C-octanoic acid breath test in the same population. The CRF patients were compared to 27 healthy volunteers. RESULTS: There was a high prevalence (48%) of dysmotility-like dyspepsia in the investigated population. The gastric emptying rates of CRF patients and healthy volunteers were significantly different (median gastric emptying t(1/2) 83 min versus 60 min, p < 0.01). Diabetic CRF patients had lower gastric emptying rates than non-diabetic CRF patients (median gastric emptying time t(1/2) 113 min versus 77 min, p < 0.01). Even the non-diabetic CRF patients had a significantly delayed gastric emptying rate compared to the healthy volunteers (77 min versus 60 min, p < 0.05). CONCLUSION: It is concluded that dysmotility-like dyspeptic complaints and delayed gastric emptying are highly prevalent in CRF patients.     

Fusarium moniliforme contamination of maize in oesophageal cancer areas in Transkei

The prevalence of human oesophageal cytological abnormalities was determined by means of brush biopsy capsules in the adult occupants of each of 12 households in a low, an intermediate and a high oesophageal cancer rate area in Transkei during 1985 and 1986. Mild cellular changes (folic acid deficiency, atypia and mild dysplasia) as well as advanced changes (dysplasia and cancer) occurred more frequently in the occupants of households in high than in intermediate and low oesophageal cancer rate areas. The prevalence of fungi in homegrown maize from the households in each area was determined by plating surface-sterilized kernels on agar. The prevalence of Fusarium moniliforme was significantly higher (P less than 0.01) in maize from cytologically 'affected' households in the high oesophageal cancer rate area than from 'unaffected' households in the low oesophageal cancer rate area during both seasons. These results confirm previous reports on the difference in the prevalence of F. moniliforme in maize from low and high oesophageal cancer rate areas in Transkei. Whereas the previously established correlation was between F. moniliforme and oesophageal cancer rate, the present results provide evidence for an association between this fungus and oesophageal cytological abnormalities in living individuals. These people will be included in further clinical, epidemiological and aetiological studies.     

Hut lung: a domestically acquired pneumoconiosis of mixed aetiology in rural women.

A form of pneumoconiosis in rural African women termed "Transkei silicosis" has been thought to be due to silica particles inhaled while they are hand grinding maize between rocks. Twenty five women were studied who were considered to have this condition according to the following criteria: rural domicile, radiographic and lung biopsy evidence of pneumoconiosis, no exposure to mining or industry and no evidence of active tuberculosis. They were assessed for radiological, pathological, physiological and bronchoalveolar lavage fluid features. Potential aetiological factors were assessed by determining levels of exposure to respirable quartz and non-quartz containing dusts and smoke in rural dwellings during maize grinding and cooking. Most of the women were symptomless. Radiological findings ranged from a miliary pattern to extensive fibrosis resembling progressive massive fibrosis. Histological features included simple "anthracosis" in 12, anthracosis with macules in six, and mixed dust fibrosis in seven. Cell numbers and their proportions in lavage fluid were normal. More than 60% of macrophages were heavily laden with inorganic inclusions. Respirable quartz concentrations and calculated cumulative time weighted exposures were below those recommended for industry during grinding with sandstone (100% quartz) and they were even lower during grinding with dolerite containing no quartz despite the presence of an appreciable amount of quartz in the ground maize. Total respirable dust and smoke concentrations were greater than the recommended safe levels. Three women had no exposure to maize grinding. It is concluded that the inhalation of non-quartz containing dust and smoke from biomass fuelled fires is more important in the aetiology of this condition than exposure to quartz dust. The term "hut lung" may be more appropriate.     

Malabsorption of carbohydrate foods by urban blacks.

Prevalences of non-infective bowel diseases are very low in South African urban blacks compared with the white population. In seeking elucidation, using breath hydrogen measurements in series of black and white subjects, small-bowel transit time was determined, and the malabsorption of maize, wheat, and rice investigated. Median transit times in both ethnic groups were similar. Rice was fully, but wheat incompletely absorbed by both groups. Maize, the staple food of blacks, was incompletely absorbed by them, although completely absorbed by the white subjects. Carbohydrate consumption is high in the black population (60-65% of total energy intake). It is probable that in blacks, despite their now eating a low-fibre diet, an expected increase in large-bowel diseases has been inhibited in part by the protective mechanism of fermentation of malabsorbed maize and wheat.     

Does Reduction in Gastric Acid Secretion in Bariatric Surgery Increase Diet-Induced Thermogenesis?

Background: Patients who have undergone gastrectomy for benign ulcer do not develop obesity. Furthermore, morbidly obese patients who undergo biliopancreatic diversion (BPD), Roux-en-Y gastric bypass (RYGBP) and vertical banded gastroplasty (VBG) plus truncal vagotomy, may lose more weight compared with patients who undergo VBG alone. A common characteristic of the above is the reduction of gastric hydrochloric acid secretion. We investigated whether reduction in gastric acid increases dietary-induced thermogenesis because of maldigestion of foods, and this may account for the greater weight loss in the above situations. Materials and Methods: 22 volunteers without symptoms from the upper gastrointestinal tract were studied. Gastric pH was measured and resting energy expenditure (MREE), using indirect calorimetry, was determined before and 8 hours after consumption of a standard meal. Parameters were measured again after 2 months administration of proton pump inhibitors in all volunteers. Results: Although significant reduction of gastric acid secretion occurred (p<0.01), following administration of proton pump inhibitors, the fasting and postprandial MREE remained unchanged (p>0.05). Conclusions: The reduction in gastric acid secretion does not increase the energy requirements for digestion of foods and thus is neither the mechanism responsible for the increased weight loss observed after RYGBP or BPD, nor the explanation for the lean appearance of gastrectomized patients.     

Does Reduction in Gastric Acid Secretion in Bariatric Surgery Increase Diet-Induced Thermogenesis?

Background: Patients who have undergone gastrectomy for benign ulcer do not develop obesity. Furthermore, morbidly obese patients who undergo biliopancreatic diversion (BPD), Roux-en-Y gastric bypass (RYGBP) and vertical banded gastroplasty (VBG) plus truncal vagotomy, may lose more weight compared with patients who undergo VBG alone. A common characteristic of the above is the reduction of gastric hydrochloric acid secretion. We investigated whether reduction in gastric acid increases dietary- induced thermogenesis because of maldigestion of foods, and this may account for the greater weight loss in the above situations. Materials and Methods: 22 volunteers without symptoms from the upper gastrointestinal tract were studied. Gastric pH was measured and resting energy expenditure (MREE), using indirect calorimetry, was determined before and 8 hours after consumption of a standard meal. Parameters were measured again after 2 months administration of proton pump inhibitors in all volunteers. Results: Although significant reduction of gastric acid secretion occurred (p<0.01), following administration of proton pump inhibitors, the fasting and postprandial MREE remained unchanged (p>0.05). Conclusions: The reduction in gastric acid secretion does not increase the energy requirements for digestion of foods and thus is neither the mechanism responsible for the increased weight loss observed after RYGBP or BPD, nor the explanation for the lean appearance of gastrectomized patients.     

Computerized 24-hour ambulatory esophageal pH monitoring and esophagogastroduodenoscopy in the reflux patient. A comparative study.

Ambulatory 24-hour esophageal pH monitoring and esophagogastroduodenoscopy were performed in 72 patients with symptoms suggestive of gastroesophageal reflux. Additionally, 22 asymptomatic healthy volunteers underwent pH monitoring. In patients with classic reflux symptoms and endoscopic esophagitis, a mean of 5.41 minutes/hour of reflux below pH 4 was found compared to 0.70 minutes/hour in controls (p less than 0.0001). The mean number and duration of reflux events in this group were 1.51 events/hour and 4.0 minutes/event, compared with 0.31 events/hour and 2.26 minutes/event in volunteers (p less than 0.001, p less than 0.01). A new system for ambulatory esophageal pH monitoring is presented using a pH-sensitive radiotelemetry pill or a pH probe and computerized methods for ambulatory data collection, analysis, and storage. An overall sensitivity of 76% was obtained with a 91% selectivity for detection of acid reflux in 51 patients having classic symptoms of gastroesophageal reflux. Ambulatory pH monitoring was positive for acid reflux in seven of 11 patients with normal endoscopic findings. Conversely, eight of 12 patients with normal pH monitoring had endoscopic esophagitis. In 19 patients presenting with atypical symptoms or previous gastric surgery, endoscopic findings were normal in 15. Nine of these 15 were identified as acid refluxers by pH monitoring. A combined approach using both pH monitoring and endoscopy is warranted for maximal detection and quantification of disease. A clear clinical role for pH monitoring is seen in the early diagnosis of acid reflux, particularly in patients having normal endoscopic findings with nonspecific gastrointestinal complaints or previous gastric operations.     

Oesophageal cancer in three regions of South Africa.

Cancer of the oesophagus is the commonest cancer in South African black males. The highest incidence rates occur in the south of Transkei. The rate among urban blacks, especially in Soweto, is also high. This study determined risk factors for oesophageal cancer in patients in three different environments--urban Soweto, rural Ciskei and rural-urban Bophuthatswana. Males were affected more than females. The majority of patients in all three regions were smokers. With regard to alcohol consumption, most Sowetans (84%) and Ciskeians (91%), but only 57% of patients from Bophuthatswana, were drinkers. Home-brewed drinks were the main source of alcohol. Oesophageal cancer occurs in both rural and urban environments, affects people without regard to tribal ethnicity, and occurs mainly in the 6th decade; moreover, almost all patients present with advanced disease.     

Effect of dietary lipids on renal function in rats with subtotal nephrectomy

Female rats with 1-3/4 nephrectomy were divided in two groups and pair fed for five weeks diets differing in their linoleic acid content. Five weeks after subtotal nephrectomy, values for glomerular filtration rate and renal plasma flow were significantly higher and the values of blood pressure significantly lower in rats fed a diet rich in linoleic acid. Systolic blood pressure averaged 156 +/- 5.6 mm Hg in high and 215 +/- 8.1 mm Hg in low linoleic acid-fed rats. Differences in the values of blood pressure between the two groups were observed three weeks after subtotal renal ablation and persisted throughout the period of observation. Inulin clearance averaged 0.89 +/- 0.07 ml/min in the high and 0.44 +/- 0.05 ml/min in the low linoleic acid group. Protein excretion in the urine was significantly less in rats fed the high linoleic acid diet (36.9 +/- 4.4 mg/24 hr) than in those fed the low linoleic acid diet (90.1 +/- 12.5 mg/24 hr). The weight of the remnant kidney five weeks after subtotal renal ablation was greater in rats fed a low linoleic acid diet as compared to those fed a high linoleic acid diet (P less than 0.05). Glomerular lesions were more severe in rats fed a low linoleic acid diet than in those fed a high linoleic acid diet. Feeding high linoleic acid diets to normal and subtotally nephrectomized rats increased the content of linoleic and arachidonic acid in renal cortex and medulla.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of dietary calcium on stone forming propensity

PURPOSE: Epidemiological studies have reported that high calcium diet protects against kidney stone formation in normal subjects. This metabolic study was designed to elucidate the physiological and physicochemical effects conferring this apparent protection. MATERIALS AND METHODS: A total of 21 normal volunteers underwent 2 phases of study in a crossover, randomized design, wherein they consumed constant metabolic diets that matched the estimated highest and lowest quintiles of calcium intake from published epidemiological studies. RESULTS: Urinary calcium was significantly greater on the high calcium diet (148 +/- 55 versus 118 +/- 43 mg. daily, p <0.01, p <0.01) but urinary oxalate did not differ between diets. There was no difference in relative saturation ratio of calcium oxalate between the 2 diets. The high calcium diet significantly increased saturation of brushite and decreased that of uric acid. Due to the other differences between the diets (more fluid, potassium, magnesium and phosphate in the high calcium diet), the high calcium diet also increased 24-hour urinary volume, potassium, phosphorus, pH and citrate. After adjustment of these confounding variables, the high calcium diet significantly increased relative saturation ratio of calcium oxalate by 24%. CONCLUSIONS: High calcium diet from published epidemiological studies does not alter the propensity for calcium oxalate crystallization in normal subjects despite increased urinary calcium and unaltered urinary oxalate because of the greater amounts of ingested fluid, potassium and phosphate. However, high calcium intake alone, without concomitant changes in the diet, poses a modest risk for calcium stone formation.     

Some aspects of household diet and family income problems in Transkei

Apparent levels of household diet, perceptions of diet and food production, rural water supplies, attitudes to birth control, and household incomes and expenditure of families in rural areas in Transkei were studied. The results revealed problems of deficiencies in family energy intake and low incomes, such that at least 40% of rural families were living in a state of poverty. There is urgent need for an integrated development approach aimed at fulfilling basic needs.     

Protective effect of fruits, vegetables and the Mediterranean diet on asthma and allergies among children in Crete

BACKGROUND: Atopy is not uncommon among children living in rural Crete, but wheeze and rhinitis are rare. A study was undertaken to examine whether this discrepancy could be attributed to a high consumption of fresh fruit and vegetables or adherence to a traditional Mediterranean diet. METHODS: A cross-sectional survey was performed in 690 children aged 7-18 years in rural Crete. Parents completed a questionnaire on their child's respiratory and allergic symptoms and a 58-item food frequency questionnaire. Adherence to a Mediterranean diet was measured using a scale with 12 dietary items. Children underwent skin prick tests with 10 common aeroallergens. RESULTS: 80% of children ate fresh fruit (and 68% vegetables) at least twice a day. The intake of grapes, oranges, apples, and fresh tomatoes-the main local products in Crete-had no association with atopy but was protective for wheezing and rhinitis. A high consumption of nuts was found to be inversely associated with wheezing (OR 0.46; 95% CI 0.20 to 0.98), whereas margarine increased the risk of both wheeze (OR 2.19; 95% CI 1.01 to 4.82) and allergic rhinitis (OR 2.10; 95% CI 1.31 to 3.37). A high level of adherence to the Mediterranean diet was protective for allergic rhinitis (OR 0.34; 95% CI 0.18 to 0.64) while a more modest protection was observed for wheezing and atopy. CONCLUSION: The results of this study suggest a beneficial effect of commonly consumed fruits, vegetables and nuts, and of a high adherence to a traditional Mediterranean diet during childhood on symptoms of asthma and rhinitis. Diet may explain the relative lack of allergic symptoms in this population.     

Dietary fatty acids correlate with prostate cancer biopsy grade and volume in Jamaican men

PURPOSE: Jamaica has the highest incidence of prostate cancer in the world. Dietary fat is associated with prostate cancer. The Omega6 polyunsaturated fatty acids have been shown to stimulate prostate carcinogenesis and the Jamaican diet is rich in linoleic acid. We hypothesized positive correlations between Omega6 polyunsaturated fatty acid, prostate specific antigen and prostate biopsy pathology. MATERIALS AND METHODS: A total of 148 men were enrolled in Kingston, Jamaica. Serum prostate specific antigen and erythrocyte membrane polyunsaturated fatty acids were analyzed. Men with prostate specific antigen 2.6 ng/ml or greater underwent biopsy. Histopathological and statistical analyses were performed on available data. RESULTS: Of the 54 men who underwent biopsy 24 had prostate cancer, 17 had a Gleason score of 7 or greater and 11 had a tumor volume of 50% or greater. There were significant positive correlations between linoleic acid and Gleason score (p = 0.009), and the linoleic acid-to-docosahexaenoic acid (Omega3) ratio and tumor volume (p = 0.03). There was a significant negative correlation between the arachidonic acid (Omega6)-to-docosapentanoic acid (Omega3) ratio and Gleason score (p = 0.04). Statistical correlations between prostate specific antigen and polyunsaturated fatty acids were inconsistent. CONCLUSIONS: The positive correlations between linoleic acid and Gleason score, and the linoleic acid-to-docosahexaenoic acid ratio and tumor volume support studies showing that Omega6 polyunsaturated fatty acids stimulate and Omega3 polyunsaturated fatty acids inhibit prostate cancer growth. The negative correlation between the arachidonic acid-to-docosapentanoic acid ratio and Gleason score supports studies that demonstrate increased metabolism of arachidonic acid in prostate cancer to form carcinogenic metabolites, namely prostaglandin E2. Our findings support the association between dietary fatty acids and prostate cancer, and they warrant further dietary and tissue studies in high risk populations.     

Effects of 5 different diets on urinary risk factors for calcium oxalate kidney stone formation: evidence of different renal handling mechanisms in different race groups

PURPOSE: Since the incidence of renal calculi in the South African black population is extremely rare while in white subjects it occurs at the same rate as elsewhere in the western world, we investigated the possibility that different renal handling mechanisms in response to different dietary challenges might occur in the 2 race groups. MATERIALS AND METHODS: We administered 5 different dietary protocols, including low calcium, high oxalate, vitamin C, high salt and lacto-vegetarian, to 10 healthy male subjects from each race group. We collected 24-hour urine at baseline and after 4 days on the prescribed diet which were analyzed for biochemical and physicochemical risk factors. Dietary intake was controlled throughout the experimental period. A 24-hour dietary recall questionnaire was recorded at baseline and analyzed using food composition tables. Statistical analysis of variance was performed on all the data. RESULTS: The low calcium diet caused statistically significant changes only in black subjects, which consisted of urinary oxalate increase (0.17 to 0.23 mmol./24 hours, p = 0.01), relative supersaturation of calcium oxalate decrease (1.88 to 0.97, p = 0.03) and relative supersaturation of brushite increase (0.85 to 1.69, p = 0.03). The high oxalate diet caused statistically significant changes in both race groups but these changes were different in the 2 groups. In white subjects urinary pH increased (6.24 to 6.62, p = 0.01), potassium excretion increased (40.01 to 73.49, p = 0.01) and relative supersaturation of brushite increased (1.34 to 2.12, p = 0.05). In black subjects urinary citrate increased (1.94 to 2.99 mmol./24 hours, p = 0.01). Clinically unimportant changes occurred in both race groups after the other 3 diets. CONCLUSIONS: Renal handling of dietary calcium and oxalate in South African black and white subjects is different and may explain the different stone incidence in the 2 race groups.     

Effects of dietary linoleic acid enrichment on induction of immune complex nephritis in mice

In pharmacologic doses E series prostaglandins attenuate the development of immune complex nephritis. We studied the effect of the dietary prostaglandin precursor linoleic acid on murine apoferritin-induced immune complex glomerulonephritis. High, normal, or low linoleic acid diets were fed to mice for 4 weeks prior to and during the intraperitoneal apoferritin administration. A high linoleic acid diet feeding was associated with less proteinuria, less renal histologic damage, and prevented a rise in serum creatinine. We conclude that linoleic acid has a protective effect on the development of murine apoferritin-induced immune complex nephritis.     

Assessment of respiratory symptoms with dual pH monitoring in patients with gastro-oesophageal reflux disease

BACKGROUND: Gastro-oesophageal reflux disease (GORD) is a commonly underestimated aetiological factor in patients with respiratory symptoms. In this study, acid reflux in healthy volunteers and patients with GORD with and without respiratory symptoms was investigated by dual pH monitoring. METHODS: Thirty healthy volunteers and 43 patients with GORD underwent oesophageal manometry and dual pH monitoring with one probe in the proximal and one in the distal oesophagus. Nineteen of the 43 patients complained of respiratory symptoms. RESULTS: There were no differences in proximal probe measurements between volunteers and patients without respiratory symptoms. Patients with GORD and respiratory symptoms had a higher prevalence of abnormally high exposure to gastric juice and more reflux episodes in the proximal oesophagus compared with patients with GORD and no respiratory symptoms. Some 17 of 19 patients with GORD and respiratory symptoms showed deteriorated oesophageal body motility. CONCLUSION: Dual pH monitoring is feasible and well tolerated, and provides an objective means of evaluating patients with GORD and respiratory symptoms. Prolonged exposure of the proximal oesophagus to gastric juice and disorders of oesophageal body motility seem to be responsible for the development of respiratory symptoms.     

Clinical significance of the fractional excretion of anions in metabolic acidosis.

The fractional excretion of anions has been proposed as a new index for the differential diagnosis of metabolic acidosis, identifying the properties of the conjugate base by examining the renal handling of the anion. Here, we investigated clinical significance of the fractional excretion of anions in pathophysiologic diagnosis of metabolic acidosis by measuring urine ammonium (NH4+) excretion, the ratio of A plasma anion gap/delta plasma HCO3- concentration (deltaAG/deltaHCO3-), and fractional excretion of anions in three different groups of metabolic acidosis: acid overproduction (8 patients with lactic acidosis, 8 with diabetic ketoacidosis, 3 with hippuric acidosis following glue sniffing), acid underexcretion (10 patients with chronic renal failure) and normal controls (10 normal volunteers who underwent 3-day NH4Cl loading). As expected, urine NH4+ excretion was higher in overproduction acidosis than in acid-loaded normal controls (88.1 +/- 12.3 vs. 54.0 +/- 3.7 mmol/day, p < 0.05), and it was lower in chronic renal failure than in acid-loaded normal controls (12.8 +/- 1.7 vs. 54.0 +/- 3.7 mmol/day, p < 0.05). The fractional excretion of anions had no difference between overproduction acidosis and chronic renal failure (41.2 +/- 42.8% vs. 41.0 +/- 8.1%). However, the fractional excretion of anions showed significant differences between the subgroups in acid overproduction (lactic acidosis, 4.7 +/- 0.3%; diabetic ketoacidosis, 45.8 +/- 3.1%; hippuric acidosis, 126.0 +/- 14.4%; p < 0.05). The ratio of plasma deltaAG/deltaHCO3- also exhibited significant differences between the subgroups in acid overproduction (lactic acidosis, 1.5 +/- 0.1; diabetic ketoacidosis, 1.0 +/- 0.1; hippuric acidosis, 0.3 +/- 0.1; p < 0.05). There was an inverse linear correlation between the fractional excretion of anions and the ratio of plasma deltaAG/deltaHCO3- (r2 =-0.89, p < 0.05). In conclusion, determination of the fractional excretion of anions may provide a useful clue to the differential diagnosis of metabolic acidosis caused by acid overproduction.     

Effects of clear liquids on gastric volume and pH in healthy volunteers

The effects of clear liquids on gastric volume and pH were examined in 30 healthy ASA physical status I volunteers. After overnight fasting, a Salem-sump nasogastric tube was inserted and gastric contents were removed for measurement of volume and pH. Gastric contents were then reinserted through the nasogastric tube into the stomach. The volunteers were randomly divided into three groups: group 1 (n = 10) received 240 mL water, group 2 (n = 10) received 240 mL coffee, and group 3 (n = 10) received 240 mL pulp-free orange juice. All liquids were administered orally. Gastric contents were then again aspirated, measured for volume and pH, and reinserted through the nasogastric tube every half hour until gastric volume was less than 25 mL. All volunteers had gastric volumes less than 25 mL with a slight decrease in pH within 2 h of orally taking one of the three 240-mL liquids. These data suggest that if patients have ingested a moderate amount of clear liquids it is safe to conduct general anesthesia after a 2-h fast in healthy surgical patients.