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Background: Whole-grain cereal foods including rye have been identified as providing significant health benefits that do not occur when refined-cereal foods are ingested. Objectives: Foods (90 g) containing whole-grain rye flour and whole-grain wheat flour were compared with low-fiber refined-cereal foods for their effects on markers of bowel health and the metabolic markers insulin and glucose. Design: Three 4-wk interventions were undertaken in a randomized crossover design with 28 overweight men aged 40-65 y who had no history of bowel disease. Against a background intake of 14 g dietary fiber (DF), the men were fed low-fiber cereal grain foods providing 5 g DF for a total of 19 g DF/d. High-fiber wheat foods provided 18 g DF, and high-fiber rye foods provided 18 g DF, both giving a total of 32 g DF/d. Fecal samples (48-h) and fasting and postprandial blood samples were collected at the end of each period and assayed. Results: Both high-fiber rye and wheat foods increased fecal output by 33-36% (P = 0.004) and reduced fecal [beta]-glucuronidase activity by 29% (P = 0.027). Postprandial plasma insulin was decreased by 46-49% (P = 0.0001) and postprandial plasma glucose by 16-19% (P = 0.0005). Rye foods were associated with significantly (P = 0.0001) increased plasma enterolactone (47% and 71%) and fecal butyrate (26% and 36%), relative to wheat and low-fiber options, respectively. Conclusions: High-fiber rye and wheat food consumption improved several markers of bowel and metabolic health relative to that of low-fiber food. Fiber from rye appears more effective than that from wheat in overall improvement of biomarkers of bowel health. KEY WORDS Wheat, rye, dietary fiber, bowel health, glucose, insulin, butyrate, enterolactone, cereal

The relationship between high levels of cholesterol in the blood and an increased risk of coronary heart disease (CHD) has been well established. In recent years, research has focused on the influence of diet on fat and cholesterol levels in the blood. Previous studies have shown that dietary fiber, specifically water-soluble fibers such as pectin and gums, can lower blood cholesterol levels. However, insoluble dietary fibers, such as cellulose and lignin, do not lower blood cholesterol. Oat and barley grains are almost 50 percent soluble fiber. Barley contains beta-glucan, a soluble dietary fiber, while wheat is mostly made of insoluble cellulose fiber. To investigate further the effect of dietary fiber on blood cholesterol levels, 21 men (aged 30 to 59) with mildly elevated blood cholesterol levels (hypercholesteremia) followed a four-week diet that included either barley or wheat. For the second four weeks of the study the two diet groups were switched; those on the barley diet changed to the wheat diet and vice versa. On the barley diet, total cholesterol levels decreased by 6 percent on average, and low-density-lipoprotein (LDL) cholesterol decreased by 7 percent. The wheat diet did not lower blood cholesterol levels. Blood triglycerides and glucose were not altered by either diet. These findings indicate that barley can lower blood cholesterol levels in men with hypercholesteremia. (Consumer Summary produced by Reliance Medical Information, Inc.)

Alterations in folate status may play an important role in carcinogenesis. The aim of this study was to examine the effect of a diminished folate status on azoxymethane (AOM)-induced intestinal tumours in Sprague–Dawley rats. A total of 125 weanling male rats were divided into five equal groups and fed semi-purified diets containing either 8 mg/kg folate or no folate. After 4 weeks on experimental diets, all animals received three weekly subcutaneous injections of AOM at a dose rate of 15 mg/kg bodyweight. The animals were necropsied after 26 weeks. Rats with a diminished folate status, evident by significantly reduced blood and colonic folate concentrations and elevated plasma homocysteine levels, had significantly (P < 0.01) lower incidence and number of small intestinal and colonic tumours compared with rats displaying an adequate folate status. There was a significant decrease in the incidence of colonic adenocarcinomas (P < 0.01) and size of colonic tumours observed in the rats displaying a diminished folate status. This study shows that a diminished folate status was associated with a decrease in the development of AOM-induced colorectal cancers. The decrease in risk may be attributed to the known role of folate in cell multiplication.

Management of dairy whey has often involved implementation of the most economical disposal methods, including discharge into waterways and onto fields or simple processing into low value commodity powders. These methods have been, and continue to be, restricted by environmental regulations and the cyclical variations in price associated with commodity products. In any modern regimen for whey management, the focus must therefore be on maximizing the value of available whey solids through greater and more varied utilization of the whey components. The whey protein constituents offer tremendous opportunities. Although whey represents a rich source of proteins with diverse food properties for nutritional, biological, and functional applications, commercial exploitation of these proteins has not been widespread because of a restricted applications base, a lack of viable industrial technologies for protein fractionation, and inconsistency in product quality. These shortcomings are being addressed through the development of novel and commercially relevant whey processing technologies, the preparation of new whey protein fractions, and the exploitation of the properties of these fractions in food and in nontraditional applications. Examples include the following developments: 1) whey proteins as physiologically functional food ingredients, 2) α-lactalbumin and β-lactoglobulin as nutritional and specialized physically functional food ingredients, and 3) minor protein components as specialized food ingredients and as important biotechnological reagents. Specific examples include the isolation and utilization of lactoferrin and the replacement of fetal bovine serum in tissue cell culture applications with a growth factor extract isolated from whey.

Radionuclide angiography was used to examine the influence of dietary fat on cardiac function in the common marmoset monkey (Callithrix jacchus jacchus) under barbiturate anaesthesia. Animals were fed for 6-8 months with a low fat (4.5%) reference diet or the same diet supplemented (12%) with sunflower seed oil or sheep fat. Although there was a tendency towards increased heart rate, left ventricular ejection fraction, peak ejection rate, and peak filling rate in both fat supplemented groups, significant increases in heart rate (+50%), peak ejection rate (+71%), and peak filling rate (+84%) were found with sheep fat supplementation, whereas only the vegetable oil supplement produced a significant improvement in left ventricular ejection fraction (+23%). There were no differences in resting blood pressure, and the main consequence of dietary fat supplementation was a major increase in apparent cardiac oxygen consumption (+58%) with the sheep fat diet, as determined by the pressure-rate index. Infusion of isoprenaline hydrochloride (0.2 µg·kg–1·min–1) increased all indices of cardiac function towards common maxima. There were no differences in either the depth or duration of anaesthesia between dietary groups. It therefore is unlikely that this contributed to any of the observed dietary induced differences in cardiac function. It is suggested that dietary saturated animal fat increased cardiac work and oxygen consumption at rest to the extent that functional reserve to respond to stress was significantly diminished. Feeding a linoleic acid rich polyunsaturated vegetable oil supplement was, however, accompanied by evidence of some improvement in left ventricular ejection fraction.