Adult dietary patterns with increased bean consumption are associated with greater overall shortfall nutrient intakes, lower added sugar, improved weight-related outcomes and better diet quality.

BACKGROUND: Limited evidence is available that focuses on beans within American dietary patterns and health. The purpose of this study was to identify commonly consumed adult dietary patterns that included beans and compare shortfall nutrient intakes and diet quality, relative to adults whose typical dietary pattern did not include beans. METHODS: The analyses used data from the National Health and Nutrition Examination Survey, 2001-2018. Cluster analysis was used to identify bean patterns of consumption, while the USDA food coding system defined daily beans consumed. Five bean dietary patterns of consumption were identified, of which four patterns included both canned beans and dry beans, while one pattern had no bean consumption. Bean consumption was defined as those consuming kidney beans, black beans, chickpeas, and/or pinto beans. RESULTS: Adults consuming Bean Dietary Patterns 1, 2, 3 and 4 had significantly higher diet quality scores (as assessed by USDA's Healthy Eating Index-2015) compared to the no-bean pattern (61.2 ± 0.5, 58.9 ± 0.5, 55.2 ± 0.4 and 56.5 ± 0.8 vs 48.8 ± 0.2 p's < 0.0001). Bean consumers also had significantly higher intakes of several shortfall nutrients (choline, alpha-linolenic acid, folate, iron, magnesium and vitamin E) relative to non-consumers of beans. Similarly, intake of dietary fiber, potassium and calcium, all nutrients of public health concern were significantly higher in bean patterns compared to no-beans. Bean Dietary Pattern 1 (~ 13.5% of total daily kcal from beans or ~ 2 servings of beans/day) and 2 (~ 9.5% of total daily kcal from beans or ~ 1.7 servings of beans/day) were significantly associated with lower BMI, decreased body weight and improved waist circumference relative to no-beans. CONCLUSIONS: Dietary patterns that are rich in canned and dry beans were associated with significantly higher diet quality scores and greater intake of shortfall nutrients, including nutrients of public health concern. Bean dietary patterns were also associated with improved weight-related outcomes. Dietary guidance should consider the nutrient and health benefits associated with the promotion of increased canned and dry bean consumption in American dietary patterns.

Positive Health Outcomes Associated with Live Microbe Intake from Foods, Including Fermented Foods, Assessed using the NHANES Database.

BACKGROUND: Live dietary microbes have been hypothesized to contribute to human health but direct evidence is lacking. OBJECTIVES: This study aimed to determine whether the dietary consumption of live microbes is linked to improved health outcomes. METHODS: Data from the NHANES 2001-2018 were used to assess microbial intake and their adjusted associations with selected physiological parameters (e.g., blood pressure, anthropometric measures, and biomarkers) among adults aged 19 y and older. Regression models were constructed to assess the microbial intake with each physiological parameter and adjusted for demographics and other covariates. Microbial intake was assessed as both a continuous variable and a 3-level categorical variable. Fermented foods were assessed in a separate model. RESULTS: In continuous models, an additional 100-g intake of microbe-containing foods was associated with a lower systolic blood pressure (regression coefficient: -0.331; 95% CI: -0.447, -0.215 mm Hg), C-reactive protein (-0.013; 95% CI: -0.019, -0.008 mg/dL), plasma glucose -0.347; 95% CI: -0.570, -0.124 mg/dL), plasma insulin (-0.201; 95% CI: -0.304, -0.099 µU/mL), triglyceride (-1.389; 95% CI: -2.672, -0.106 mg/dL), waist circumference (-0.554; 95% CI: -0.679, -0.428 cm), and BMI -0.217; 95% CI: -0.273, -0.160 kg/m2) levels and a higher level of high density lipoprotein cholesterols (0.432; 95% CI: 0.289, 0.574 mg/dL). Patterns were broadly similar when microbial intake was assessed categorically and when fermented foods were assessed separately. CONCLUSIONS: To our knowledge, this study is the first to quantify, in a nationally representative data set of American adults and using stable sets of covariates in the regression models, the adjusted associations of dietary intakes of live microbes with a variety of outcomes, such as anthropometric measures, biomarkers, and blood pressure levels. Our findings suggest that foods with higher microbial concentrations are associated with modest health improvements across a range of outcomes.

Dietary Guidelines Meet NOVA: Developing a Menu for A Healthy Dietary Pattern Using Ultra-Processed Foods.

BACKGROUND: A proposed topic for the 2025 Dietary Guidelines for Americans (DGA) Scientific Advisory Committee to address is the relationship between dietary patterns with ultra-processed foods (UPF) and body composition and weight status. Implementing the NOVA system, the most commonly applied framework for determining whether a food is "ultra-processed," in dietary guidance could omit several nutrient-dense foods from recommended healthy diets in the DGA. OBJECTIVE: The purpose of this proof-of-concept study was to determine the feasibility of building a menu that aligns with recommendations for a healthy dietary pattern from the 2020 DGA and includes ≥80% kcal from UPF as defined by NOVA. DESIGN: To accomplish this objective, we first developed a list of foods that fit NOVA criteria for UPF, fit within dietary patterns in the 2020 DGA, and are commonly consumed by Americans. We then used these foods to develop a 7-d, 2000 kcal menu modeled on MyPyramid sample menus and assessed this menu for nutrient content as well as for diet quality using the Healthy Eating Index-2015 (HEI-2015). RESULTS: In the ultra-processed DGA menu that was created, 91% of kcal were from UPF, or NOVA category 4. The HEI-2015 score was 86 out of a possible 100 points. This sample menu did not achieve a perfect score due primarily to excess sodium and an insufficient amount of whole grains. This menu provided adequate amounts of all macro- and micronutrients except vitamin D, vitamin E, and choline. CONCLUSIONS: Healthy dietary patterns can include most of their energy from UPF, still receive a high diet quality score, and contain adequate amounts of most macro- and micronutrients.

A Classification System for Defining and Estimating Dietary Intake of Live Microbes in US Adults and Children.

BACKGROUND: Consuming live microbes in foods may benefit human health. Live microbe estimates have not previously been associated with individual foods in dietary databases. OBJECTIVES: We aimed to estimate intake of live microbes in US children (aged 2-18 y) and adults (≥19 y) (n = 74,466; 51.2% female). METHODS: Using cross-sectional data from the NHANES (2001-2018), experts assigned foods an estimated level of live microbes per gram [low (Lo), <104 CFU/g; medium (Med), 104-107 CFU/g; or high (Hi), >107 CFU/g]. Probiotic dietary supplements were also assessed. The mean intake of each live microbe category and the percentages of subjects who ate from each live microbe category were determined. Nutrients from foods with live microbes were also determined using the population ratio method. Because the Hi category comprised primarily fermented dairy foods, we also looked at aggregated data for Med or Hi (MedHi), which included an expanded range of live microbe-containing foods, including fruits and vegetables. RESULTS: Our analysis showed that 52%, 20%, and 59% of children/adolescents, and 61%, 26%, and 67% of adults, consumed Med, Hi, or MedHi foods, respectively. Per capita intake of Med, Hi, and MedHi foods was 69, 16, and 85 g/d for children/adolescents, and 106, 21, and 127 g/d for adults, respectively. The proportion of subjects who consumed live microbes and overall per capita intake increased significantly over the 9 cycles/18-y study period (0.9-3.1 g/d per cycle in children across categories and 1.4 g/d per cycle in adults for the Med category). CONCLUSIONS: This study indicated that children, adolescents, and adults in the United States steadily increased their consumption of foods with live microbes between the earliest (2001-2002) and latest (2017-2018) survey cycles. Additional research is needed to determine the relations between exposure to live microbes in foods and specific health outcomes or biomarkers.

Dietary fibers reduce obesity-related disorders: mechanisms of action.

PURPOSE OF REVIEW: Dietary fibers decrease risk of cardiovascular disease and obesity, but the most important mechanisms for fiber's protective properties are debated. The purpose of the review is to summarize the recent human studies that examine mechanisms how dietary fiber decreases risk of obesity-related disorders. RECENT FINDINGS: Dietary fiber has effects throughout the digestive tract that decrease risk of obesity-related diseases. Soluble, viscous fibers slow absorption of and decrease serum cholesterol. Intake of dietary fiber enhances satiety and reduces food intake at future meals. The importance of gut fermentation and changes in the gut microbiota and metabolites are linked to decrease risk for obesity-related disorders. Dietary fibers alter the gut microbiota and produce metabolites such as short-chain fatty acids that may explain fiber's role in obesity prevention and treatment. Dietary fiber encompasses many plant compounds, so conclusions that dietary fiber reduces or treats obesity-related disorders must be considered by the fiber was fed in the study. SUMMARY: Dietary fiber prevents and treats obesity-related disorders. Mechanisms for this protection include decreased absorption of macronutrients and enhanced satiety. Changes in the gut microbiota and short-chain fatty acids are emerging mechanisms to explain why high fiber diets protect against obesity and have a role in obesity treatment.

Should There Be a Recommended Daily Intake of Microbes?

The collective findings from human microbiome research, randomized controlled trials on specific microbes (i.e., probiotics), and associative studies of fermented dairy consumption provide evidence for the beneficial effects of the regular consumption of safe live microbes. To test the hypothesis that the inclusion of safe, live microbes in the diet supports and improves health, we propose assessment of the types and evidentiary quality of the data available on microbe intake, including the assembly and evaluation of evidence available from dietary databases. Such an analysis would help to identify gaps in the evidence needed to test this hypothesis, which can then be used to formulate and direct initiatives focused on prospective and randomized controlled trials on live microbe consumption. Outcomes will establish whether or not the evidence exists, or can be generated, to support the establishment of dietary recommendations for live microbes.

Considerations for best practices in studies of fiber or other dietary components and the intestinal microbiome.

A 2-day workshop organized by the National Institutes of Health and U.S. Department of Agriculture included 16 presentations focused on the role of diet in alterations of the gastrointestinal microbiome, primarily that of the colon. Although thousands of research projects have been funded by U.S. federal agencies to study the intestinal microbiome of humans and a variety of animal models, only a minority addresses dietary effects, and a small subset is described in sufficient detail to allow reproduction of a study. Whereas there are standards being developed for many aspects of microbiome studies, such as sample collection, nucleic acid extraction, data handling, etc., none has been proposed for the dietary component; thus this workshop focused on the latter specific point. It is important to foster rigor in design and reproducibility of published studies to maintain high quality and enable designs that can be compared in systematic reviews. Speakers addressed the influence of the structure of the fermentable carbohydrate on the microbiota and the variables to consider in design of studies using animals, in vitro models, and human subjects. For all types of studies, strengths and weaknesses of various designs were highlighted, and for human studies, comparisons between controlled feeding and observational designs were discussed. Because of the lack of published, best-diet formulations for specific research questions, the main recommendation is to describe dietary ingredients and treatments in as much detail as possible to allow reproduction by other scientists.

Fructooligosaccharides and appetite.

PURPOSE OF REVIEW: Dietary fiber may play a role in obesity prevention through reduction of body weight and control of appetite, however, not all fibers are created equally, and characteristics of fiber such as viscosity, fermentability and solubility may affect appetite differently. RECENT FINDINGS: Although early studies supported that fructan fibers, including inulin, fructooligosaccharides, and oligofructose affected satiety, more recent studies are less supportive. We found that a higher dose of fiber such as oligofructose (16 g/day) is needed and for a longer duration (12-16 weeks) to detect differences in appetite and subsequent energy intake, whereas, practical amounts of fructooligosaccharides, less than 10 g/day, generally do not affect satiety or food intake. It should be noted that there are many sources of fructan fibers, both in native foods, chicory roots, agave, and Jerusalem artichokes and isolated forms that vary in chain length. SUMMARY: Fructan fibers, which include fructooligosaccharides, oligofructose, and inulin, provided in low doses (<10 g/day), generally do not affect measures of human appetite including satiety or food intake and should not be recommended as a fiber with sole satiating power.

The Scientific Basis of Guideline Recommendations on Sugar Intake: A Systematic Review.

BACKGROUND: The relationship between sugar and health is affected by energy balance, macronutrient substitutions, and diet and lifestyle patterns. Several authoritative organizations have issued public health guidelines addressing dietary sugars. PURPOSE: To systematically review guidelines on sugar intake and assess consistency of recommendations, methodological quality of guidelines, and the quality of evidence supporting each recommendation. DATA SOURCES: MEDLINE, EMBASE, and Web of Science (1995 to September 2016); guideline registries; and gray literature (bibliographies, Google, and experts). STUDY SELECTION: Guidelines addressing sugar intake that reported their methods of development and were published in English between 1995 and 2016. DATA EXTRACTION: Three reviewers independently assessed guideline quality using the Appraisal of Guidelines for Research and Evaluation, 2nd edition (AGREE II), instrument. To assess evidence quality, articles supporting recommendations were independently reviewed and their quality was determined by using GRADE (Grading of Recommendations Assessment, Development and Evaluation) methods. DATA SYNTHESIS: The search identified 9 guidelines that offered 12 recommendations. Each of the reviewed guidelines indicated a suggested decrease in the consumption of foods containing nonintrinsic sugars. The guidelines scored poorly on AGREE II criteria, specifically in rigor of development, applicability, and editorial independence. Seven recommendations provided nonquantitative guidance; 5 recommended less than 25% to less than 5% of total calories from nonintrinsic sugars. The recommendations were based on various health concerns, including nutrient displacement, dental caries, and weight gain. Quality of evidence supporting recommendations was low to very low. LIMITATION: The authors conducted the study independent of the funding source, which is primarily supported by the food and agriculture industry. CONCLUSION: Guidelines on dietary sugar do not meet criteria for trustworthy recommendations and are based on low-quality evidence. Public health officials (when promulgating these recommendations) and their public audience (when considering dietary behavior) should be aware of these limitations. PRIMARY FUNDING SOURCE: Technical Committee on Dietary Carbohydrates of the North American branch of the International Life Sciences Institute. (PROSPERO: CRD42015029182).

Gastrointestinal tolerance of low FODMAP oral nutrition supplements in healthy human subjects: a randomized controlled trial.

BACKGROUND: There has been increasing interest in utilizing a diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) for the treatment of irritable bowel syndrome (IBS), a functional gastrointestinal disease. While studies have indicated that this diet can be effective at symptom reduction, it is a restrictive diet and patients may find it challenging to find low FODMAP products to meet their nutrient needs. The primary objective of this study was to assess the gastrointestinal (GI) tolerance of three low FODMAP oral nutrition supplements (ONS) in healthy adults. METHODS: A double-blind randomized controlled crossover study was conducted in 21 healthy adults (19-32 years). Fasted subjects consumed one of four treatments at each visit, with a one week wash out period between visits. Each participant received all treatments. Treatments included three low FODMAP ONS formulas (A, B, and C) as well as a positive control consisting of 5 g fructooligosaccharides (FOS) mixed in lactose-free milk. Breath hydrogen was measured at baseline, 1, 2, 3, and 4 h post treatment consumption. Subjective GI symptom questionnaires were completed at baseline, 0.5, 1, 1.5, 2, 3, 4, 12, 24 and 48 h following treatment consumption. Mean breath hydrogen concentrations and baseline corrected area under the curve for both breath hydrogen and GI symptoms were analyzed and compared between treatments. Significance was determined at P < 0.05. RESULTS: The positive control resulted in higher breath hydrogen response compared to all three of the low FODMAP ONS beverages at 3 and 4 h after consumption. There were no differences in GI symptom response between treatments. CONCLUSIONS: All treatments were well tolerated in healthy participants. The low FODMAP formulas resulted in a lower breath hydrogen response compared to the positive control, and may be better tolerated in individuals with IBS. More research should be conducted to better understand the GI tolerance of low FODMAP ONS in individuals with IBS. TRIAL REGISTRATION: The protocol for this study was registered on ClinicalTrials.gov in January 2016 (Clinical Trials ID: NCT02667184 ).

Impact of Agaricus bisporus mushroom consumption on satiety and food intake.

Previous studies on mushrooms suggest that they can be more satiating than meat, but this effect has not been studied with protein-matched amounts. The objective of this study was to assess the differences with satiety and ten-day food intake between A. bisporus mushrooms (226 g) and meat (28 g) in a randomized open-label crossover study. Thirty-two healthy participants (17 women, 15 men) consumed two servings of mushrooms or meat for ten days. On the first day, fasted participants consumed protein-matched breakfasts. Participants rated their satiety using visual analogue scales (VAS) at baseline and at regular intervals after the meal. Three hours later, participants were served an ad libitum lunch. Participants were given mushrooms or meat to consume at home for the following nine days. Energy intake was assessed at the ad libitum lunch, and participants also completed diet diaries on the day of the study, day 2, and day 10. Participants reported less hunger (p = 0.045), greater fullness (p = 0.05), and decreased prospective consumption (p = 0.03) after the mushroom breakfast. There were no significant differences in participant ratings of satisfaction (p = 0.10). There were also no statistically significant differences in energy intake at the ad libitum lunch or with the diet diaries from days 1 (p = 0.61), 2 (p = 0.77), or 10 (p = 0.69). Mushroom consumption did increase fiber intake on days 1, 2, and 10 but the difference in fiber consumption was only statistically significant on day 2 (p = 0.0001). The mushroom intervention also did not affect energy intake over the ten day feeding period.

In vitro analysis of partially hydrolyzed guar gum fermentation on identified gut microbiota.

BACKGROUND: Prebiotic dietary fibers resist digestion in the upper gastrointestinal tract and allow for stimulation of bacteria in the distal intestine and colon. Stimulation of bacteria among different individuals varies greatly, depending on a wide range of variables. OBJECTIVE: To determine the range of differences in response between individuals, a preclinical in vitro fermentation was conducted with six fecal donors. The primary objective was to compare the fecal microbiota of six individuals at baseline, 12 h and 24 h post-exposure to partially hydrolyzed guar gum (PHGG). METHOD: Fecal donations were collected from six healthy individuals consuming a non-specific Western diet, free of antibiotic treatments in the past year, not affected by any GI diseases and not consuming any probiotic or prebiotic supplements. Fecal samples were exposed to 0.5 g of PHGG and measured for bacterial changes at 0, 12 and 24 h based on 16S rRNA sequencing. RESULTS: Parabacteroides increased from 3.48% of sequence reads to 10.62% of sequence reads after 24 h (p = 0.0181) and Bacteroidetes increased from 45.89% of sequence reads to 50.29% of sequence reads (p = 0.0008). CONCLUSIONS: PHGG stimulates growth of Parabacteroides, a genus of bacteria that have been inversely associated with IBS and ulcerative colitis. PHGG provides stimulation of beneficial Bacteroidetes (Bacteroides and Parabacteroides), which may be correlated with many positive health markers and outcomes. PHGG is a prebiotic dietary fiber that is readily fermentable.

The effects of the combination of egg and fiber on appetite, glycemic response and food intake in normal weight adults - a randomized, controlled, crossover trial.

This study evaluated appetite and glycemic effects of egg-based breakfasts, containing high and moderate protein (30 g protein and 20 g protein +7 g fiber, respectively) compared to a low-protein cereal breakfast (10 g protein) examined in healthy adults (N = 48; age 24 ± 1 yr; BMI 23 ± 1 kg/m(2); mean ± SE). Meals provided 390 kcal/serving and equal fat content. Food intake was measured at an ad libitum lunch meal and blood glucose response was measured. Visual analog scales (VAS) were used to assess hunger, satisfaction, fullness, and prospective food intake. The egg-based breakfast meal with high protein produced greater overall satiety (p < 0.0001), and both high protein and moderate protein with fiber egg-based breakfasts reduced postprandial glycemic response (p < 0.005) and food intake (p < 0.05) at subsequent meal (by 135 kcal and 69 kcal; effect sizes 0.44 and 0.23, respectively) compared to a cereal-based breakfast with low protein and fiber.

Dairy Foods: Current Evidence of their Effects on Bone, Cardiometabolic, Cognitive, and Digestive Health.

Dairy foods have long been considered nutrient-dense and health-promoting products that offer many health benefits to their consumers. This review is an overview of the health benefits associated with them, drawing from recent research conducted on the associations of dairy food components with bone, cardiometabolic, cognitive, and digestive health in cross-sectional and intervention studies. Each section details the associations of dairy with a certain aspect of health and focuses on the benefits milk product consumption may have on the prevention and management of chronic health conditions such as osteoporosis, the metabolic syndrome, and dementia. Dairy food components, as well as the potential biological mechanisms responsible for their effects on health, are also addressed. Although several of the biological mechanisms warrant further research, current evidence suggests that dairy consumption confers some beneficial effects to bone, cardiometabolic, cognitive, and digestive health. Due to its nutrient profile and the current evidence of its benefits, at least 1 daily serving of a dairy item is recommended by the dietary guidelines of several countries. Yet, even in the United States, many individuals do not consume the recommended 3 cups of dairy foods a day. Therefore, this review concludes with a description of the current public health impact of dairy food research as well as recommendations for the food industry to formulate dairy foods that are both palatable and health-promoting for consumers.

Functionality of Sugars in Foods and Health.

Overweight and obesity are global health problems that affect more than 1.9 billion adults who are overweight, and of these 600 million are obese. In the United States, these problems affect 60% of the population. Critical to these statistics is the association with increased risk of cardiovascular disease, type 2 diabetes, and metabolic syndrome among other noncommunicable diseases. Many factors, including sugars, have been charged as potential causes. However, obesity and overweight and their attendant health problems continue to increase despite the fact that there is a decline in the consumption of sugars. Sugars vary in their types and structure. From a food science perspective, sugars present an array of attributes that extend beyond taste, flavor, color, and texture to aspects such as structure and shelf-life of foods. From a public health perspective, there is considerable controversy about the effect of sugar relative to satiety, digestion, and noncommunicable diseases. This comprehensive overview from experts in food science, nutrition and health, sensory science, and biochemistry describes the technical and functional roles of sugar in food production, provides a balanced evidence-based assessment of the literature and addresses many prevalent health issues commonly ascribed to sugar by the media, consumer groups, international scientific organizations, and policy makers. The preponderance of the evidence indicates that sugar as such does not contribute to adverse health outcomes when consumed under isocaloric conditions. The evidence generally indicates, as noted by the 2010 Dietary Guidelines Advisory Committee, that sugar, like any other caloric macronutrient, such as protein and fat, when consumed in excess leads to conditions such as obesity and related comorbidities. More recently, the 2015-2020 Dietary Guidelines for Americans recommended limiting dietary sugar to 10% of total energy in an effort to reduced the risk of these noncommunicable diseases.

The challenges of nutrition policymaking.

In my over three decades of work in the field of food and nutrition, I have participated in many efforts that seek new policy initiatives in the hopes that these programs can curb rates of obesity and chronic disease and help consumers make healthier dietary choices. Because of the profound effect that many of these policies have on consumers, the food environment, federal nutrition assistance programs and subsequent policy and regulatory recommendations, it is imperative that only the strongest, best available evidence is used to set policy. This review evaluates methods by which current nutrition policies use scientific research as well as provides recommendations for how best to ensure future nutrition policies are truly science-based and likely to have a meaningful impact on public health. Specifically, this review will: Describe the current food and nutrition policy environment in the US Examine how science is used in federal food and nutrition policymaking efforts, using the Dietary Guidelines for Americans (DGA) as an example Describe strong versus weak science as well as what types of studies are most appropriate for use in policymaking Discuss the potential effects and consequences of making policy recommendations in the absence of scientific consensus or agreement Make recommendations to support the present and ongoing development of science-based policy likely to positively impact public health.

Are restrictive guidelines for added sugars science based?

Added sugar regulations and recommendations have been proposed by policy makers around the world. With no universal definition, limited access to added sugar values in food products and no analytical difference from intrinsic sugars, added sugar recommendations present a unique challenge. Average added sugar intake by American adults is approximately 13% of total energy intake, and recommendations have been made as low 5% of total energy intake. In addition to public health recommendations, the Food and Drug Administration has proposed the inclusion of added sugar data to the Nutrition and Supplemental Facts Panel. The adoption of such regulations would have implications for both consumers as well as the food industry. There are certainly advantages to including added sugar data to the Nutrition Facts Panel; however, consumer research does not consistently show the addition of this information to improve consumer knowledge. With excess calorie consumption resulting in weight gain and increased risk of obesity and obesity related co-morbidities, added sugar consumption should be minimized. However, there is currently no evidence stating that added sugar is more harmful than excess calories from any other food source. The addition of restrictive added sugar recommendations may not be the most effective intervention in the treatment and prevention of obesity and other health concerns.

Significance of Inulin Fructans in the Human Diet.

This paper reviews the physicochemical properties and nutritional significance of inulin fructans (oligofructose and inulin). These compounds are naturally present in a large number of food crops and serve in our diet as dietary fiber. Inulin fructans can be isolated and purified from the chicory root and used as ingredients in a large range of foods to improve structure and/or taste and to increase the intake of dietary fiber. Inulin fructans have a low caloric value, are safe, and generally well tolerated up to a level of 20 g/d. They exert a range of effects, which can be differentiated into direct effects on the gut and the intestinal flora and indirect systemic effects. Direct effects on the gut include prebiotic (bifidogenic) effects, improvement of bowel habits and bowel function in constipated subjects, increased colonic absorption of minerals (Ca and Mg), and secretion of satiety hormones. Indirect effects are on blood lipids, bone mineral content, the immune system, and energy homeostasis. These issues are discussed and it is argued that promising avenues for research are particularly in the areas of energy homeostasis and systemic low-grade inflammation in relation to changes in the composition of the intestinal microbiota.

Bran fibers and satiety in women who do not exhibit restrained eating.

BACKGROUND: Foods that are high in dietary fiber can promote satiety, but previous studies report conflicting results. OBJECTIVE: The objective was to determine differences in satiety response to three conditions (10 g oat bran, 10 g barley bran and a low fiber condition) consumed at dinner and breakfast. In addition, we compared energy intake at an ad libitum lunch after consumption of the breakfast bars. DESIGN: Randomized, double-blind crossover study. PARTICIPANTS/SETTING: 42 normal weight women. INTERVENTION: Women consumed a dinner food bar from one of the three conditions the evening before testing. On test mornings, fasted women consumed the corresponding breakfast food bar with their choice of coffee, tea or water. An ad libitum pizza lunch was served 4 hours after breakfast. PRIMARY OUTCOMES: Visual analogue scales (VAS) were used to assess satiety at baseline, 15, 30, 45, 60, 90, 120, 180 and 240 minutes. Energy intake was assessed by an ad libitum pizza lunch (4 hours after breakfast) and 24-hour energy intake was measured by a food diary. STATISTICAL ANALYSES: Treatments were compared using the mixed-effects linear models. Outcomes are reported as mean ± SEM. RESULTS: There were no significant differences among conditions on any of the satiety scales and no significant differences among conditions in energy consumed at lunch or over 24 hours. The fiber bars were well tolerated and no significant differences were found for gastrointestinal tolerance. CONCLUSIONS: Our results do not support an effect of bran fibers on satiety above a low fiber control. We acknowledge results of this study may be intricately tied to the choice of a single pizza lunch, as other ad libitum meal options could have resulted in different outcomes.