Jennifer Erickson

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).

Total, added, and free sugars: Are restrictive guidelines science - Based or achievable?

Sugar consumption, especially added sugars, is under attack. Various government and health authorities have suggested new sugar recommendations and guidelines as low as 5% of total calories from free sugars. Definitions for total sugars, free sugars, and added sugars are not standardized, nor are there accepted nutrient databases for this information. Our objective was to measure total sugars and added sugars in sample meal plans created by the United States Department of Agriculture (USDA) and the Academy of Nutrition and Dietetics (AND). Utilizing the Nutrition Data System for Research (NDSR) nutritional database, results found that plans created by the USDA and AND averaged 5.1% and 3.1% calories from added sugar, 8.7% and 3.1% from free sugar, and 23.3% and 21.1% as total sugars respectively. Compliance with proposed added sugar recommendations would require strict dietary compliance and may not be sustainable for many Americans. Without an accepted definition and equation for calculating added sugar, added sugar recommendations are arbitrary and may reduce intakes of nutrient-rich, recommended foods, such as yogurt, whole grains, and tart fruits including cranberries, cherries, and grapefruit. Added sugars are one part of excess calorie intake; however, compliance with low added sugar recommendations may not be achievable for the general public.

Dietary guidance for pulses: the challenge and opportunity to be part of both the vegetable and protein food groups.

Pulses are a dry, edible variety of beans, peas, and lentils that have been consumed for 10,000 years. Pulses are rich in plant‐based protein and fiber, as well as micronutrients such as iron and potassium. The satiating effect of both fiber and protein assists in managing weight and combating obesity. The high fiber content and low glycemic index of pulses aid people with diabetes in maintaining blood glucose and insulin levels. Pulse consumption may improve serum lipid levels to reduce the risk of cardiovascular disease. Pulses developed as a member of both the protein and vegetable food groups as a result of its high content of plant‐based protein and dietary fiber. The last two revisions of the Dietary Guidelines saw the transformation from the MyPyramid “meat and beans group” to the MyPlate “protein foods group,” a nutrient name rather than a food source. Research suggests that consumers better identify with food source examples rather than nutrient names. The 2015 Dietary Guidelines also came with a new area: sustainable diets. Encouraging the consumption of sustainable food sources, like pulses, is imperative to ensuring a secure, healthy food supply for the U.S. population over time and for future generations.

Prebiotic Dietary Fiber and Gut Health: Comparing the in Vitro Fermentations of Beta-Glucan, Inulin and Xylooligosaccharide

Prebiotic dietary fiber supplements are commonly consumed to help meet fiber recommendations and improve gastrointestinal health by stimulating beneficial bacteria and the production of short-chain fatty acids (SCFAs), molecules beneficial to host health. The objective of this research project was to compare potential prebiotic effects and fermentability of five commonly consumed fibers using an in vitro fermentation system measuring changes in fecal microbiota, total gas production and formation of common SCFAs. Fecal donations were collected from three healthy volunteers. Materials analyzed included: pure beta-glucan, Oatwell (commercially available oat-bran containing 22% oat β-glucan), xylooligosaccharides (XOS), WholeFiber (dried chicory root containing inulin, pectin, and hemi/celluloses), and pure inulin. Oatwell had the highest production of propionate at 12 h (4.76 μmol/mL) compared to inulin, WholeFiber and XOS samples (p < 0.03). Oatwell’s effect was similar to those of the pure beta-glucan samples, both samples promoted the highest mean propionate production at 24 h. XOS resulted in a significant increase in the genus Bifidobacterium after 24 h of fermentation (0 h:0.67 OTUs (operational taxonomic unit); 24 h:5.22 OTUs; p = 0.038). Inulin and WholeFiber increased the beneficial genus Collinsella, consistent with findings in clinical studies. All analyzed compounds were fermentable and promoted the formation of beneficial SCFAs.

Satiety Effects of Lentils in a Calorie Matched Fruit Smoothie

The food environment is changing, with consumers being more health conscious and concerned about the wholesomeness of their food than ever before. Consumers are looking for nutritious whole food alternatives to fill their plates and stomachs. Pulse grains, rich in both protein and fiber, may be the ideal candidate to promote satiety at meals. In a crossover feeding study, participants consumed calorie-matched fruit smoothies prepared with either an ice cream base or pureed red lentils. Self-reported satiety, blood glucose response, and ad libitum food intake at a secondary meal were all measured along with breath hydrogen and methane and gastrointestinal tolerance. While there was no significant difference in satiety response or energy intake at the secondary meal, the nutrient profile of the lentil smoothie was improved with increased protein and fiber and dramatically lower fat content. Blood glucose response was not statistically different between the 2 treatments. Both smoothies were generally well tolerated; however, there was a slightly elevated AUC for perceived gastrointestinal tolerance over 24 h in the lentil smoothie. No difference in breath hydrogen or methane response was seen between treatments. The substitution of lentils into a meal is not likely to improve satiety; however lentils are a good source of fiber and protein and can greatly improve nutritional content of the meal.

Fermentability of Novel Type-4 Resistant Starches in In Vitro System

Resistant starches are non-digestible starches that are fermented in the colon by microbiota. These carbohydrates are prebiotic and can be beneficial to consumer health. Many types of resistant starch exist with varying physical properties that may result in differences in fermentability. The objective of this research project was to compare potential prebiotic effects and fermentability of four novel resistant starches using an in vitro fermentation system and measuring changes in total gas production, pH, and formation of SCFAs (short chain fatty acids). Fecal donations were collected from seven healthy volunteers. Four novel resistant starches, modified potato starch (MPS), modified tapioca starch (MTS), and modified maize starches (MMS-1 and MMS-2), were analyzed and compared to polydextrose and short chain fructooligosaccharides (FOS) as controls. After twenty-four hours of fermentation, MPS and MTS responded similarly in gas production (74 mL; 70.6 mL respectively), pH (5.93; 5.93 respectively), and SCFA production (Acetate: 115; 124, Propionate: 21; 26, Butyrate: 29; 31 μmol/mL respectively). While MMS-1 had similar gas production and individual SCFA production, the pH was significantly higher (6.06). The fermentation of MMS-2 produced the least amount of gas (22 mL), with a higher pH (6.34), and lower acetate production (78.4 μmol/mL). All analyzed compounds were fermentable and promoted the formation of beneficial SCFAs.

White Grape Juice Elicits a Lower Breath Hydrogen Response Compared with Apple Juice in Healthy Human Subjects: A Randomized Controlled Trial

BACKGROUND Diets low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPS) are used to manage symptoms in individuals with irritable bowel syndrome. Although effective at reducing symptoms, the diet can be complex and restrictive. In addition, there are still large gaps in the literature and many foods with unclear effects in the gastrointestinal (GI) tract, like fruit juice. Although many fruits are allowable on a low-FODMAP diet, consumption of all fruit juice is generally cautioned due to the large fructose load contained in juice, regardless of the glucose concentration. Very little research exists regarding the importance of limiting fructose load during a low-FODMAP diet; therefore, individuals following a low-FODMAP diet may be unnecessarily restricting their diets. OBJECTIVE To determine whether there is a difference in GI tolerance between juice from a high-FODMAP fruit (apple juice) and juice from a low-FODMAP fruit (white grape juice) in healthy human subjects. The goal is to provide insight into the role of juice in a low-FODMAP diet. METHODS A double-blind, randomized, controlled crossover study was conducted with 40 healthy adults. Fasted subjects consumed 12 oz of either apple juice or white grape juice. Breath hydrogen measures were taken at baseline, 1, 2, and 3 hours. Subjective GI tolerance surveys were completed at the same time intervals and at 12 and 24 hours. Breath hydrogen and GI symptoms were assessed with area under the curve analysis. Significance was determined with a two-sided t test with a P value <0.05. RESULTS Consumption of apple juice resulted in a greater mean breath hydrogen area under the curve at 23.3 ppm/hour (95% CI 13.0 to 33.6) compared with white grape juice at 5.8 ppm/hour (95% CI -4.6 to 16.1) (P<0.001). No differences in reported GI symptoms were seen between treatments. CONCLUSIONS Both juices were well tolerated and neither produced any severe symptoms in healthy adults. White grape juice consumption resulted in only a small rise in breath hydrogen, which may suggest excluding foods only because of the high fructose load could be unnecessarily restrictive. The results of this study suggest that the fructose-to-glucose ratio is likely more important than the total fructose load of the food when considering the acceptability of a food on a low-FODMAP diet. More research is needed in individuals with irritable bowel syndrome to determine whether white grape juice and other juices from low-FODMAP fruits could be additional beverage options for individuals following a low-FODMAP diet.

Health Effects and Sources of Prebiotic Dietary Fiber

Abstract Prebiotic dietary fibers act as carbon sources for primary and secondary fermentation pathways in the colon, and support digestive health in many ways. Fructooligosaccharides, inulin, and galactooligosaccharides are universally agreed-upon prebiotics. The objective of this paper is to summarize the 8 most prominent health benefits of prebiotic dietary fibers that are due to their fermentability by colonic microbiota, as well as summarize the 8 categories of prebiotic dietary fibers that support these health benefits. Although not all categories exhibit similar effects in human studies, all of these categories promote digestive health due to their fermentability. Scientific and regulatory definitions of prebiotics differ greatly, although health benefits of these compounds are uniformly agreed upon to be due to their fermentability by gut microbiota. Scientific evidence suggests that 8 categories of compounds all exhibit health benefits related to their metabolism by colonic taxa.