The effects of vitamin D intake and status on symptom severity and quality-of-life in adults with irritable bowel syndrome (IBS): a systematic review and meta-analysis.

IMPORTANCE: Many individuals with irritable bowel syndrome (IBS) have insufficient or deficient serum 25-hydroxyvitamin D [25(OH)D] status; however, it is not clear if improved vitamin D nutritional status through higher intake can improve symptom severity and quality of life. OBJECTIVE: This systematic review and meta-analysis aimed to identify if changes in vitamin D intake or status affect symptom severity and quality of life in adults with IBS.Data Sources: MEDLINE®, Cochrane Central Register of Controlled Trials, Global Health, EMBASE, and Web-of-Science databases were systematically searched for relevant articles to August 12, 2024, in the English language.Study Selection: Clinical trials, prospective observational studies, and Mendelian randomization (MR) analyses reporting the effect of vitamin D intake or status on IBS-related outcomes were included.Data Extraction and Synthesis: Article review and data extraction were conducted by 2 authors following the PRISMA guidelines. Random effects meta-analyses and the Nutrition Quality Evaluation Strengthening Tools to assess risk of bias were employed for randomized controlled trials.Main Outcome(s) and Measure(s): Primary outcomes included measures of serum 25(OH)D status, symptom severity, and quality of life. RESULTS: 12 studies from 15 articles were included (n = 7 RCTs; n = 3 single-arm interventions; n = 2 MR). Seven study populations had deficient (<20 ng/mL) and three had insufficient (21-29 ng/mL) baseline serum 25(OH)D status. RCTs measured changes in serum 25(OH)D after 6-26 wks with 3,000 IU daily to 50,000 IU bi-weekly vitamin D dosages. Meta-analyses of low risk-of-bias RCTs revealed increased 25(OH)D levels in groups treated with oral vitamin D compared to placebo (n = 5; Pooled mean difference [95% CI]: 20.33 [12.91, 27.74] ng/mL; I2 = 97.9%). Quality of life scores improved significantly in deficient populations (n = 3; 3.19 [2.14, 4.24]; I2 = 0.0%). Non-significant decreased trends in IBS symptom severity were shown across populations (n = 6: -25.89 [-55.26, 3.48]; I2 = 92.8%). CONCLUSION: Moderate level evidence indicate vitamin D supplementation may improve status in adults with IBS and quality of life in those with deficient status at baseline.

QUESTION: Do changes in vitamin D intake or status affect symptom severity and quality of life in adults with irritable bowel syndrome?FindingsIn this systematic review and meta-analysis, moderate level evidence supports vitamin D supplementation for improving serum 25-hydroxyvitamin D status in adults with IBS and for increasing quality of life scores in those with deficient status at baseline.Meaning: Vitamin D supplementation may improve quality of life in IBS patients with deficient serum 25-hydroxyvitamin D status.

Nutrient Profiling Systems, Front of Pack Labeling, and Consumer Behavior.

PURPOSE OF REVIEW: Guiding consumers toward more healthful food choices may help address the high prevalence of poor dietary quality and diet-related diseases. The use of front-of-package labels (FOPL) on food items is expanding to provide focused nutritional information or representations, often based upon nutrient profiling systems. RECENT FINDINGS: FOPL provide a source of nutrition and health information that is readily understood by consumers, including those with limited literacy. There is evidence that FOPL can shift consumer behavior toward more nutritious and healthful choices. However, assessments of the effectiveness of FOPL have been restricted in scope and rely largely on simulation models rather than real-world environments. FOPL are a direct source of nutritional guidance at the point-of-purchase and provide an opportunity to convey critical information on ingredients that are associated with health promotion and/or increased risk of non-communicable diseases. However, limited evidence regarding the most effective forms of FOPL to achieve behavior change and challenges from the food industry impedes the establishment of standardized nutrient profiles and algorithms. Future opportunities for FOPL include the potential for integrating nutritional profiles with non-nutrient factors affecting health such as food processing and environmental sustainability.

Breaking Academic Silos: Pedagogical Recommendations for Equitable Obesity Prevention Training and Research During an Age of Nutrition Polarization.

Introduction: Obesity is a preventable chronic condition and a risk factor for poor health and early mortality. Weight stigma and weight-neutral medicine are popular topics in social media that are often at odds with current medical guidelines on obesity treatment and prevention. This conflict may erode the public's trust in science, impede research progress on preventing obesity in marginalized groups, and uphold the ongoing and historical lack of diversity among nutrition trainees. Methods: The authors conducted a series of student-led dialogue sessions with nutrition graduate students in Boston, Massachusetts, from March to May 2023 to understand perceptions of obesity research, health equity, and racism and discrimination. This article summarizes the lessons learned and provides pedagogical recommendations for jointly addressing obesity at the population level and the recruitment, training, and retention of diverse scholars, clinicians, and public health practitioners. Results: Dialogue sessions revealed that students perceive a disproportionate focus on the harms of obesity as a chronic disease, highlighting that inadequate attention is given to weight stigma and discrimination. Some participants believed that weight-based discrimination is equally detrimental to individual health and wellbeing as having obesity. Discussions also emphasized the need to pinpoint the multidimensional and cultural manifestations of weight stigma, which necessitates collaboration across social sectors and academic disciplines. Students recognized the urgent need to apply an equity lens to obesity research and teaching but felt limited in their access to experts within nutrition science who specialize in racism, discrimination, eating disorders, and weight stigma. Conclusions: This study identified concrete opportunities for urgently needed new training and research in population-level obesity prevention, emphasizing antiracism, harm reduction, and elimination of stigma and bias across multiple levels of science and society. Overall, the decision to use the BMI within pedagogy and training must be explicitly stated-research, population surveillance, decision-making, or treatment pedagogy and training-while acknowledging its strengths and limitations across diverse settings. Finally, the social determinants of obesity should incorporate not only weight stigma but also racism and multiple forms of discrimination.

Very low calorie ketogenic diets in overweight and obesity treatment: Effects on anthropometric parameters, body composition, satiety, lipid profile and microbiota.

According to the World Health Organization (WHO) the prevalence of obesity tripled worldwide since 1975. Obesity prevention and treatment is based upon lifestyle changes involving eating habits, physical activity and behaviour therapy. Various dietary patterns have been used as nutritional strategies and, in recent years, interest has been shown in very low calorie ketogenic diets (VLCKD) that provide less than 800 calories (kcal), no more than 20-50 g/day of carbohydrates and 0.8-1.5 g/kg ideal body weight of protein. We conducted a literature review of all clinical trials published between January 2014-November 2019 on people with obesity (PWO) that evaluated VLCKD effects on anthropometric parameters, body composition, satiety, lipid profile and microbiota. Findings from literature showed that VLCKD could be useful to ameliorate the quality of life and sleep of PWO. It leads to a rapid weight loss and results in improvements in body mass index (BMI = kg/m2), waist circumference and fat mass reduction preserving lean body mass and resting metabolic rate. This eating pattern reduced the desire to eat and increased satiety. Little is known regarding the effects of VLCKD on the microbiota of PWO for which it is important to conduct further studies.

Systematic Review of Dietary Patterns and Sustainability in the United States.

Improving awareness and accessibility of healthy diets are key challenges for health professionals and policymakers alike. While the US government has been assessing and encouraging nutritious diets via the Dietary Guidelines for Americans (DGA) since 1980, the long-term sustainability, and thus availability, of those diets has received less attention. The 2015 Dietary Guidelines Advisory Committee (DGAC) examined the evidence on sustainable diets for the first time, but this topic was not included within the scope of work for the 2020 DGAC. The objective of this study was to systematically review the evidence on US dietary patterns and sustainability outcomes published from 2015 to 2019 replicating the 2015 DGAC methodology. The 22 studies meeting inclusion criteria reveal a rapid expansion of research on US dietary patterns and sustainability, including 8 studies comparing the sustainability of DGA-compliant dietary patterns with current US diets. Our results challenge prior findings that diets adhering to national dietary guidelines are more sustainable than current average diets and indicate that the Healthy US-style dietary pattern recommended by the DGA may lead to similar or increased greenhouse gas emissions, energy use, and water use compared with the current US diet. However, consistent with previous research, studies meeting inclusion criteria generally support the conclusion that, among healthy dietary patterns, those higher in plant-based foods and lower in animal-based foods would be beneficial for environmental sustainability. Additional research is needed to further evaluate ways to improve food system sustainability through both dietary shifts and agricultural practices in the United States.

Effects of food supplementation on cognitive function, cerebral blood flow, and nutritional status in young children at risk of undernutrition: randomized controlled trial.

OBJECTIVE: To assess the effects of food supplementation on improving working memory and additional measures including cerebral blood flow in children at risk of undernutrition. DESIGN: Randomized controlled trial. SETTING: 10 villages in Guinea-Bissau. PARTICIPANTS: 1059 children aged 15 months to 7 years; children younger than 4 were the primary population. INTERVENTIONS: Supervised isocaloric servings (≈1300 kJ, five mornings each week, 23 weeks) of a new food supplement (NEWSUP, high in plant polyphenols and omega 3 fatty acids, within a wide variety and high fortification of micronutrients, and a high protein content), or a fortified blended food (FBF) used in nutrition programs, or a control meal (traditional rice breakfast). MAIN OUTCOME MEASUREMENTS: The primary outcome was working memory, a core executive function predicting long term academic achievement. Additional outcomes were hemoglobin concentration, growth, body composition, and index of cerebral blood flow (CBFi). In addition to an intention-to-treat analysis, a predefined per protocol analysis was conducted in children who consumed at least 75% of the supplement (820/925, 89%). The primary outcome was assessed by a multivariable Poisson model; other outcomes were assessed by multivariable linear mixed models. RESULTS: Among children younger than 4, randomization to NEWSUP increased working memory compared with the control meal (rate ratio 1.20, 95% confidence interval 1.02 to 1.41, P=0.03), with a larger effect in the per protocol population (1.25, 1.06 to 1.47, P=0.009). NEWSUP also increased hemoglobin concentration among children with anemia (adjusted mean difference 0.65 g/dL, 95% confidence interval 0.23 to 1.07, P=0.003) compared with the control meal, decreased body mass index z score gain (-0.23, -0.43 to -0.02, P=0.03), and increased lean tissue accretion (2.98 cm2, 0.04 to 5.92, P=0.046) with less fat (-5.82 cm2, -11.28 to -0.36, P=0.04) compared with FBF. Additionally, NEWSUP increased CBFi compared with the control meal and FBF in both age groups combined (1.14 mm2/s×10-8, 0.10 to 2.23, P=0.04 for both comparisons). Among children aged 4 and older, NEWSUP had no significant effect on working memory or anemia, but increased lean tissue compared with FBF (4.31 cm2, 0.34 to 8.28, P=0.03). CONCLUSIONS: Childhood undernutrition is associated with long term impairment in cognition. Contrary to current understanding, supplementary feeding for 23 weeks could improve executive function, brain health, and nutritional status in vulnerable young children living in low income countries. Further research is needed to optimize nutritional prescriptions for regenerative improvements in cognitive function, and to test effectiveness in other vulnerable groups. TRIAL REGISTRATION: ClinicalTrials.gov NCT03017209.

Measured energy content of frequently purchased restaurant meals: multi-country cross sectional study.

OBJECTIVE: To measure the energy content of frequently ordered meals from full service and fast food restaurants in five countries and compare values with US data. DESIGN: Cross sectional survey. SETTING: 223 meals from 111 randomly selected full service and fast food restaurants serving popular cuisines in Brazil, China, Finland, Ghana, and India were the primary sampling unit; 10 meals from five worksite canteens were also studied in Finland. The observational unit was frequently ordered meals in selected restaurants. MAIN OUTCOME MEASURE: Meal energy content, measured by bomb calorimetry. RESULTS: Compared with the US, weighted mean energy of restaurant meals was lower only in China (719 (95% confidence interval 646 to 799) kcal versus 1088 (1002 to 1181) kcal; P<0.001). In analysis of variance models, fast food contained 33% less energy than full service meals (P<0.001). In Finland, worksite canteens provided 25% less energy than full service and fast food restaurants (mean 880 (SD 156) versus 1166 (298); P=0.009). Country, restaurant type, number of meal components, and meal weight predicted meal energy in a factorial analysis of variance (R2=0.62, P<0.001). Ninety four per cent of full service meals and 72% of fast food meals contained at least 600 kcal. Modeling indicated that, except in China, consuming current servings of a full service and a fast food meal daily would supply between 70% and 120% of the daily energy requirements for a sedentary woman, without additional meals, drinks, snacks, appetizers, or desserts. CONCLUSION: Very high dietary energy content of both full service and fast food restaurant meals is a widespread phenomenon that is probably supporting global obesity and provides a valid intervention target.