No abstract

Imbalances in the gut microbiota, the bacteria that inhabit the intestines, are central to the pathogenesis of obesity. This systematic review assesses the association between the gut microbiota and weight loss in overweight/obese adults and its potential manipulation as a target for treating obesity. This review identified 43 studies using the keywords 'overweight' or 'obesity' and 'microbiota' and related terms; among these studies, 17 used dietary interventions, 11 used bariatric surgery and 15 used microbiota manipulation. The studies differed in their methodologies as well as their intervention lengths. Restrictive diets decreased the microbiota abundance, correlated with nutrient deficiency rather than weight loss and generally reduced the butyrate producers Firmicutes, Lactobacillus sp. and Bifidobacterium sp. The impact of surgical intervention depended on the given technique and showed a similar effect on butyrate producers, in addition to increasing the presence of the Proteobacteria phylum, which is related to changes in the intestinal absorptive surface, pH and digestion time. Probiotics differed in strain and duration with diverse effects on the microbiota, and they tended to reduce body fat. Prebiotics had a bifidogenic effect and increased butyrate producers, likely due to cross-feeding interactions, contributing to the gut barrier and improving metabolic outcomes. All of the interventions under consideration had impacts on the gut microbiota, although they did not always correlate with weight loss. These results show that restrictive diets and bariatric surgery reduce microbial abundance and promote changes in microbial composition that could have long-term detrimental effects on the colon. In contrast, prebiotics might restore a healthy microbiome and reduce body fat.

BackgroundCow's milk is the most common food allergen in infants and the diagnosis of cow's milk allergy is difficult, even with the use of several diagnostic tests. Therefore, elimination diets and challenge tests are essential for the diagnosis and treatment of this disorder. The aim of this study is to report the clinical presentation and nutritional status of children evaluated by pediatric gastroenterologists for the assessment of symptoms suggestive of cow's milk allergy.MethodsAn observational cross-sectional study was performed among 9,478 patients evaluated by 30 pediatric gastroenterologists for 40 days in 5 different geographical regions in Brazil. Clinical data were collected from patients with symptoms suggestive of cow's milk allergy. The nutritional status of infants (age ≤ 24 months) seen for the first time was evaluated according to z-scores for weight-for-age, weight-for-height, and height-for-age. Epi-Info (CDC-NCHS, 2000) software was used to calculate z-scores.ResultsThe prevalence of suspected cow's milk allergy in the study population was 5.4% (513/9,478), and the incidence was 2.2% (211/9,478). Among 159 infants seen at first evaluation, 15.1% presented with a low weight-for-age z score (< -2.0 standard deviation - SD), 8.7% with a low weight-for-height z score (< -2.0 SD), and 23.9% with a low height-for-age z score (< -2.0 SD).ConclusionThe high prevalence of nutritional deficits among infants with symptoms suggestive of cow's milk allergy indicates that effective elimination diets should be prescribed to control allergy symptoms and to prevent or treat malnutrition.

Background: There are no internationally agreed recommendations on compositional requirements of follow-up formula for young children (FUF-YC) aged 1-3 years. Aim: The aim of the study is to propose international compositional recommendations for FUF-YC. Methods: Compositional recommendations for FUF-YC were devised by expert consensus based on a detailed literature review of nutrient intakes and unmet needs in children aged 12-36 months. Results and Conclusions: Problematic nutrients with often inadequate intakes are the vitamins A, D, B12, C and folate, calcium, iron, iodine and zinc. If used, FUF-YC should be fed along with an age-appropriate mixed diet, usually contributing 1-2 cups (200-400 ml) of FUF-YC daily (approximately 15% of total energy intake). Protein from cow's milk-based formula should provide 1.6-2.7 g/100 kcal. Fat content should be 4.4-6.0 g/100 kcal. Carbohydrate should contribute 9-14 g/100 kcal with >50% from lactose. If other sugars are added, they should not exceed 10% of total carbohydrates. Calcium should provide 200 mg/100 kcal. Other micronutrient contents/100 kcal should reach 15% of the World Health Organization/Food and Agriculture Organization recommended nutrient intake values. A guidance upper level that was 3-5 times of the minimum level was established. Countries may adapt compositional requirements, considering recommended nutrient intakes, habitual diets, nutritional status and existence of micronutrient programs to ensure adequacy while preventing excessive intakes.

No abstract