Do whole-grain oat cereals reduce the need for antihypertensive medications and improve blood pressure control? Oat ingestion reduces systolic and diastolic blood pressure in patients with mild or borderline hypertension: a pilot trial. Effects on serum lipids of adding instant oats to usual American diets. Serum lipid response to a fat-modified, oatmeal-enhanced diet. Changes in whole-grain, bran, and cereal fiber consumption in relation to 8-y weight gain among men. Long-term comparison of three dietary prescriptions in the treatment of NIDDM. Randomized, controlled trial promotes physical activity and reduces consumption of sweets and sodium among overweight and obese adults. A long-term study on the effect of spontaneous consumption of reduced fat products as part of a normal diet on indicators of health. The hypocholesterolemic effects of beta-glucan in oatmeal and oat bran. A dose-controlled study.
Our study compared 2 whole grain oat-based cereals with 2 refined grain wheat-based cereals to determine their effects on the need for antihypertensive medications in people with high blood pressure (BP).
                This 12-week, randomized controlled parallel-group trial with = 6 weeks of voluntary follow-up was designed to investigate the antihypertensive effects of oats. After 4 weeks of baseline feeding, medication dose was maintained or reduced by half or completely throughout the middle 4 weeks of the study. In the final 4 weeks, participants continued cereal consumption; medication was adjusted according to the protocol.
                Men and women (n = 88) being treated for hypertension with a mean baseline BP below 160/100.
                Primary study outcomes included change in SBP and DBP as well as antihypertensive medication reduction. Secondary measures included blood lipid, fasting glucose, and insulin levels and side effects related to elevated BP and increased dietary fiber intake.
                Seventy-three percent of participants in the oats group versus 42% in the control group were able to stop or reduce their medication by half. Treatment group participants whose medication was not reduced had substantial decreases in BP. The oats group experienced a 24.2-mg/dL reduction in total cholesterol levels, a 16.2-mg/dL decrease in low-density lipoprotein cholesterol levels, and a 15.03-mg/dL drop in plasma glucose levels vs controls.
                Results suggest that a diet containing soluble fiber-rich whole oats can significantly reduce the need for antihypertensive medication and improve BP control. Considering the lipid and glucose improvements as well, increased consumption of whole oats may significantly reduce cardiovascular disease risk. We assessed the short-term antihypertensive effects of soluble fiber-rich whole oat cereals when added to a standard American diet. In addition, multiple assessments of insulin sensitivity were conducted.
                This was a randomized, controlled, parallel-group pilot study designed to compare an oat cereal group (standardized to 5.52 g/day beta-glucan) to a low-fiber cereal control group (less than 1.0 g/day total fiber) over 6 weeks.
                A total of 18 hypertensive and hyperinsulinemic (= 10 U/mL or more) men and women completed the trial.
                Primary study outcomes were changes in systolic blood pressure (SBP) and diastolic blood pressure (DBP). Secondary outcomes included blood lipid, fasting glucose, and insulin levels and side effects related to elevated blood pressure and increased dietary fiber intake.
                The oat cereal group experienced a 7.5 mm Hg reduction in SBP (P &lt.01) and a 5.5 mm Hg reduction in DBP (P &lt.02), while there was virtually no change in either SBP or DBP in the control group. In the oat cereal group, a trend was observed for a lower total insulin response to a glucose load, suggesting improved insulin sensitivity. However, this could not be confirmed using estimates from the Bergman Minimal Model, perhaps because of our small sample size. The oats group experienced a significant reduction in both total cholesterol (9%) and low-density lipoprotein cholesterol (14%).
                The addition of oat cereals to the normal diet of patients with hypertension significantly reduces both SBP and DBP. Soluble fiber-rich whole oats may be an effective dietary therapy in the prevention and adjunct treatment of hypertension. This study was designed as a test of the serum lipid response and dietary adaptation to recommended daily inclusion of instant oats in an otherwise regular diet. Hypercholesterolemic adults were randomly assigned to a control or intervention group. Participants in the intervention group were given packages of instant oats and requested to eat two servings per day (approximately two ounces dry weight), substituting the oats for other carbohydrate foods in order to maintain baseline calorie intake and keep weight stable. Serum lipids were measured in blood collected by venipuncture at baseline, four weeks, and eight weeks. Baseline mean total cholesterol (TC) levels were 6.56 mmol/L and 6.39 mmol/L for intervention and control groups, respectively. After eight weeks, mean serum total cholesterol of the intervention group was lower by -0.40 mmol/L, and mean net difference in TC between the two groups was 0.32 mmol/L (95% CI: 0.09, 0.54). Low-density lipoprotein-cholesterol was similarly reduced with mean net difference of 0.25 mmol/L (95% CI: 0.02, 0.48) between the two groups. Mean soluble fiber intake increased along with slight self-imposed reductions in mean total fat, saturated fat, and dietary cholesterol intake in the intervention group. Neither group changed mean body weight. Daily inclusion of two ounces of oats appeared to facilitate reduction of serum total cholesterol and LDL-C in these hyperlipidemic individuals. The purpose of this study was to confirm and extend previous findings that serum cholesterol response to a fat-modified diet is enhanced by oat fiber. Participants (n = 236) were recruited from the Continental Illinois National Bank in Chicago. Data including weight, serum lipid level, lipoproteins, and 3-day food records were collected at baseline and every 4 weeks for 12 weeks. All participants were instructed to follow the fat-modified (Phase II) diet recommended by the American Heart Association (AHA). After 4 weeks, participants were randomly assigned to one of two groups. While both groups continued to follow the AHA diet, Group 1 was instructed to include 2 oz (56 g, dry wt) of oatmeal, isocalorically substituted for other carbohydrate foods. Group 2 served as the control and consumed no oat products throughout the study. Serum cholesterol values at baseline and after 4 weeks of the AHA diet were similar for both groups (203.9 and 193.0 mg/dl for Group 1 and 205.3 and 194.5 mg/dl for Group 2). After 4 weeks of oatmeal intervention, mean group differences were -6.8 and -2.1 mg/dl (P = 0.008 one-tailed t test) for Groups 1 and 2, respectively. Following an additional 4 weeks of oatmeal intervention, the Group 1 mean cholesterol increased slightly (0.9 mg/dl), while the Group 2 level decreased slightly (-0.7 mg/dl). Overall serum cholesterol responses for the two groups from Visit 2 to Visit 4 were -6.0 and -2.8 mg/dl for Groups 1 and 2, respectively (P = 0.074, one tail). Changes in weight were small and nonsignificant. Subgroup analyses revealed greater reductions in serum cholesterol among participants with the highest baseline serum cholesterol (-8.0 mg/dl vs -1.7 mg/dl for Subgroups 1 and 2, respectively). These data support previous findings that inclusion of oatmeal in a fat-modified diet is helpful in lowering serum cholesterol, particularly for individuals with elevated serum cholesterol levels. Epidemiologic studies that directly examine changes in whole-grain consumption in relation to weight gain are sparse, and characterization of this association has been obscured by methodologic inconsistencies in the assessment of whole grains.
                We aimed to ascertain the associations between changes in new quantitative estimates of whole-grain intake and 8-y weight gain among US men.
                The study was conducted in a prospective cohort of 27 082 men aged 40-75 y at baseline in 1986. Data on lifestyle factors were obtained periodically by using self-reported questionnaires, and participants measured and reported their body weight in 1986 and 1994.
                In multivariate analyses, an increase in whole-grain intake was inversely associated with long-term weight gain (P for trend < 0.0001). A dose-response relation was observed, and for every 40-g/d increment in whole-grain intake from all foods, weight gain was reduced by 0.49 kg. Bran that was added to the diet or obtained from fortified-grain foods further reduced the risk of weight gain (P for trend = 0.01), and, for every 20 g/d increase in intake, weight gain was reduced by 0.36 kg. Changes in cereal and fruit fiber were inversely related to weight gain. No associations were observed between changes in refined-grain or added germ consumption and body weight.
                The increased consumption of whole grains was inversely related to weight gain, and the associations persisted after changes in added bran or fiber intakes were accounted for. This suggests that additional components in whole grains may contribute to favorable metabolic alterations that may reduce long-term weight gain. To compare three sets of dietary guidelines for the treatment of non-insulin-dependent diabetes (NIDDM) in free-living individuals and to observe the effects on metabolic control over an 18-month period.
                Seventy volunteer subjects with NIDDM were randomly assigned to one of three diets, a weight-management diet, a high-carbohydrate/fiber diet, or a modified-lipid diet and followed for 18 months. Nutrient intakes, weight, blood lipids, and glycemic control were measured.
                In all diet groups, glycated hemoglobin (HbA1) fell significantly before diet intervention began, remaining lower throughout the study and at follow-up 9 months later. Low-density lipoprotein (LDL) cholesterol showed a sustained fall in all groups after diet intervention. Apart from transient changes in high-density lipoprotein (HDL) cholesterol and triglyceride (TG) in the diet groups with the higher carbohydrate intake, no lasting differences were found between the three diet groups.
                In the long term, there were few differences in the outcome of the three dietary prescriptions. Even with intensive instruction, participants found it difficult to meet recommended nutrient intakes; however, specific dietary advice did result in an improvement in LDL cholesterol. Adverse changes in HDL cholesterol and TG because of diet intervention were transient. The significant improvement in glycemic control during the recruitment phase may have been the result of participants' previous dietary knowledge and the increased attention that they received during the intervention. The present study sought to assess the impact of an intervention to reduce weight and control risk factors of noncommunicable chronic diseases in overweight or obese adults who are users of primary and secondary healthcare units of the public health system of Pelotas, Brazil. We hypothesized that individuals who received an educational intervention regarding how to lose weight and prevent other noncommunicable chronic disease risk factors through nutrition would lose weight and acquire active habits during leisure time more frequently than individuals under regular care. Two hundred forty-one participants from the Nutrition Outpatient Clinic of the Medical Teaching Hospital of the Federal University of Pelotas, Brazil, aged 20 years or older and classified as overweight or obese were randomly allocated to either the intervention group (IG; n = 120) or control group (CG; n = 121). The IG received individualized nutritional care for 6 months, and the CG received individualized usual care of the health services. Intention-to-treat analyses showed that at 6 months, mean fasting glycemia and daily consumption of sweet foods and sodium were reduced, and the time spent on physical leisure activity was increased in IG. Analysis of adherence to the protocol of the study revealed that individuals from IG had lost more in body weight, waist circumference, and fasting glucose compared to the CG. Leisure time physical activity increased in IG. Individuals adhered equally to the dietetic recommendations, irrespective of the nutrition approach that was used.
                Copyright © 2010 Elsevier Inc. All rights reserved. The growing public concern with the adverse effects on health of a high fat intake has led to a proliferation on the market of reduced fat products. However, no consensus exists on the effectivity of reduced fat products to decrease energy intake. The studies that have investigated this topic have included small numbers of subjects, studied under laboratory conditions and over a relatively short period of time. Therefore, we have executed a long-term study in which volunteers had free access to both reduced fat, commercially available products in the laboratory as well as to products obtained from regular shops. We here report the feasibility of such a type of study and the effects of consumption of reduced fat products on blood levels of cholesterol, haemostasis variables, antioxidants and parameters of the immune system. The study was a multicentre parallel comparison trial of six months (so-called MSFAT-study). 241 volunteers received either reduced fat products or full-fat products and the products were clearly labelled as such. Two months before the start of the study, a 1 month adaptation period was executed to optimize the experimental procedures. Food intake was recorded before the start of the adaptation period and 2-4 weeks, 3 months and 6 months after the start of the study. Blood samples were taken before, after 2, 4 and 6 months of the study. In addition, a selection of the reduced fat and full-fat products was sensorically evaluated three times during the study by a subgroup of the volunteers. 220 volunteers completed the study. The reduced fat group consumed on average 46% less fat from the so-called MSFAT-products obtained from the shop at the laboratory than the control group and consumption of these MSFAT-products did not decrease in either of the groups during the time course of the study. The palatability of the reduced fat and full-fat products was similar and as expected, the perceived fattiness of the full-fat products was higher than that of the reduced fat products. No effects were found on blood levels of cholesterol, haemostasis variables, parameters of antioxidant status and immune system characteristics. In conclusion, the experimental manipulation of the fat content of the diet that was achieved and that remained stable throughout the 6 months of the study indicates that this type of set-up is feasible to assess the effects of long-term nutritional intervention in large groups of volunteers under semi-controlled conditions. The regular use of reduced fat products did not positively but also not adversely affect blood cholesterol levels, antioxidant status, haemostasis factors and the body's immune system. Oat cereals rich in the water-soluble fiber beta-glucan have been studied as a dietary therapy for hypercholesterolemia. To determine the hypocholesterolemic response of beta-glucan in the diet, 156 adults with low-density lipoprotein cholesterol (LDL-C) levels above 4.14 mmol/L (160 mg/dL) or between 3.37 and 4.14 mmol/L (130 and 160 mg/dL) with multiple risk factors were randomized to one of seven groups. Six groups received either oatmeal or oat bran at doses (dry weight) of 28 g (1 oz), 56 g (2 oz), and 84 g (3 oz). A seventh group received 28 g of farina (beta-glucan control). At week 6 of treatment, significant differences were found for both total cholesterol and LDL-C levels among the farina control and the treatment groups who were receiving 84 g of oatmeal, 56 g of oat bran, and 84 g of oat bran, with decreases in LDL-C levels of 10.1%, 15.9%, and 11.5%, respectively. Fifty-six grams of oat bran resulted in significantly greater reductions in LDL-C levels than 56 g of oatmeal. Nutrient analysis shows no difference in dietary fat content between these treatment groups; therefore, the higher beta-glucan content of oat bran most likely explains the significantly greater LDL-C reductions. A dose-dependent reduction in LDL-C levels with oat cereals supports the independent hypocholesterolemic effects of beta-glucan.
Despite the consistency of effects seen in trials of wholegrain oats, the positive findings should be interpreted cautiously. Many of the trials identified were short term, of poor quality and had insufficient power. Most of the trials were funded by companies with commercial interests in wholegrains. There is a need for well-designed, adequately powered, longer term randomised controlled studies in this area. In particular there is a need for randomised controlled trials on wholegrain foods and diets other than oats.