Journal of the American College of Nutrition最新文献

Objective: The purpose of the study was to assess knowledge and perceptions related to carbohydrates, including sugars, among Canadian nutrition-major undergraduates compared to those enrolled in elective nutrition courses (i.e., "nutrition-elective students").Methods: Cross-sectional surveys were distributed during class time at eight Canadian universities, which included 32 questions on demographics, knowledge and perceptions of carbohydrates and sugars. Descriptive analyses were performed. Differences between groups were tested by Chi-squared statistics.Results: A total of 1207 students (60% nutrition-majors) participated in the survey (January 2016-February 2017). Internet-based sources accounted for one-third of the sources where students obtained nutrition information. About 61% of internet-bases sources were "online" or "website" with no qualifiers, and about a quarter was from social media. A higher percentage of nutrition-majors correctly answered knowledge questions of carbohydrates compared with nutrition-elective students (p < 0.01); no difference was observed for sugars-related knowledge questions. The perceptions of sugars were generally negative and did not differ between groups.Conclusions: Several knowledge gaps and common perceptions on topics related to carbohydrates and sugars were identified; nutrition-major students performed better than nutrition-elective students on carbohydrate knowledge questions, but not sugars. These results highlight the importance of identifying methods to help students bridge knowledge gaps and develop skills to critically evaluate nutrition information from various resources and challenge personal biases.

Malnutrition is one of the greatest health challenges that affects about 2 billion people globally. Multiple factors including poverty, food insecurity, maternal health and nutritional status, mother's age at marriage and educational status, low birthweight or small for gestational age (SGA), premature births, suboptimal breastfeeding practices, unhealthy dietary and lifestyle patterns, health and immunization status of children, socioeconomic status of family, environmental and household conditions, together with cultural practices and myths, play vital role in affecting the growth of children at early age. Although child stunting has declined in Pakistan, the reduction rate is only 0.5%, which is very low. This may be due to ineffective or inappropriate intervention programs as they are mostly addressing only one issue at a time and don't use the multi-sector approach to address numerous determinants of stunting. It is therefore important to initiate cost-effective multi-tiered intervention approaches to be implemented at pre-conception, pregnancy and early postpartum stages to prevent the problems of malnutrition and stunting in Pakistani children. This review discusses the etiology of child malnutrition and stunting in Pakistan, role of various determinants of stunting and what type of intervention strategies and approaches should be developed and implemented to deal with these problems. Key teaching pointsMalnutrition is one of the greatest global health challenges.Poverty, food insecurity, socioeconomic status, unhealthy dietary patterns, maternal health and nutritional status, low birthweight, suboptimal breast feeding, environmental conditions, cultural practices and myths, are the main factors for child malnutrition and stunting in Pakistan.The slow reduction rate in child stunting may be due to inappropriate intervention programs.Cost-effective multi-tiered intervention approaches must be implemented at pre-conception, pregnancy and early postpartum stages to prevent child malnutrition and stunting in Pakistan.A holistic approach comprising nutrition and WASH interventions, together with strategies to improve the socioeconomic status be developed and implemented to resolve this dilemma.

Objective: Beef protein extracts are growing in popularity in recent years due to their purported anabolic effects as well as to their potential benefits on hematological variables. The present randomized, controlled, double-blind, cross-over study aimed to analyze the effects of beef protein supplementation on a group of male elite triathletes (Spanish National Team).

Methods: Six elite triathletes (age, 21 ± 3 years; VO_2max, 71.5 ± 3.0 ml·kg·min^-1) were randomly assigned to consume daily either 25 g of a beef supplement (BEEF) or an isoenergetic carbohydrates (CHO) supplement for 8 weeks, with both conditions being separated by a 5-week washout period. Outcomes, including blood analyses and anthropometrical measurements, were assessed before and after each 8-week intervention.

Results: No effects of supplement condition were observed on body mass nor on skinfold thicknesses, but BEEF induced significant and large benefits over CHO in the thigh cross-sectional area (3.02%, 95%CI = 1.33 to 4.71%; p = 0.028, d = 1.22). Contrary to CHO, BEEF presented a significant increase in vastus lateralis muscle thickness (p = 0.046), but differences between conditions were not significant (p = 0.173, d = 0.87). Although a significantly more favorable testosterone-to-cortisol ratio (TCR) was observed for BEEF over CHO (37%, 95% CI = 5 to 68%; p = 0.028, d = 1.29), no significant differences were found for the hematological variables (i.e., iron, ferritin, red blood cell count, hemoglobin or hematocrit).

Conclusion: Beef protein supplementation seems to facilitate a more favorable anabolic environment (i.e., increased TCR and muscle mass) in male elite triathletes, with no impact on hematological variables.

Objective: To assess the body composition and nutritional state of patients with Alzheimer's (Global Deterioration Scale GDS-4) using different methods and to investigate the correlation among methods.

Methods: A total of 25 Alzheimer GDS-4 patients participated in this transversal descriptive observational study, which used anthropometry, Mini Nutritional Assessment (MNA), the Nutrition Screening Initiative Check List (NSI) and a 24-hour recall questionnaire (R24h).

Results: Anthropometric observations pointed to obesity in patients of both sexes. The MNA showed that 76% of the population was "at risk of malnutrition", and the NSI suggested that 32% had a high nutritional risk, 48% had an "average" nutritional risk, and the remaining 20% a low nutritional risk. The Bland-Alman concordance plot between the NSI and MNA tests pointed to a high degree of agreement, meaning that both tests provided similar results for the group of studied subjects. The nutritional analysis, based on the Kruskal-Wallis test, showed there were significant differences between R24h and MNA in the case of ascorbic acid, iron, zinc and potassium (p < 0.05), and between R24h and NSI in the case of the double unsaturation index and vitamin D3 (p < 0.05). These results suggest that both questionnaires are equally valid for evaluating the nutritional status of Alzheimer patients.

Conclusion: Although the NSI and MNA tests provide similar results, we recommend an initial nutritional assessment using the NSI since it is short but provides information on any alteration in food intake as a result of restrictions and/or metabolic alterations.

Objective: Many medical disorders comprising the metabolic syndrome (MS) are becoming increasingly prominent worldwide. Accordingly, much more knowledge is necessary to design the best preventive and therapeutic regimens to combat them effectively. This investigation examines the manner and magnitude of any interplay between body fat mass (FM) and insulin resistance (IR) in the evolution of these disorders using fasting blood glucose (FBG) as the latter's surrogate. Two components of MS, IR and body FM, appear to be particularly important because they have been postulated to be primary driving forces behind the other coexisting entities. Whether and how these two components interact is uncertain to some extent.

Method: Baseline data obtained from healthy, non-diabetic volunteers involved in a number of prior clinical studies were analyzed by examining links between FBG and FM through their individual as well as combined effects on various components of MS.

Results: The present study consists of three phases. Phase 1 establishes that FM, similar to FBG, acting as an independent variable correlates significantly with various components of MS. The results even imply that FM offers a better measure for estimating generalized inflammation. Further, implied from findings in phase 2 is that FM influences inflammation not only by further augmenting IR but by additional means as well. In phase 3, where quartiles were developed based upon FBG and FM levels, the combination of relatively low FM/low FBG possesses significantly less proclivity for intensifying metabolic risk factors compared to the high FM/high FBG subset.

Conclusions: Body FM through augmenting IR as well as another mechanism(s) markedly influences optimal fitness in seemingly normal healthy, non-diabetic volunteers. Maintaining the lowest reasonable levels of IR or body FM should bring one closer to long-term, ideal health, but improving the two jointly is an even better option.

Objective: This study investigated the accuracy of a flash glucose monitoring system (FGMS) in a postprandial setting.

Methods: Ten fasted adults without diabetes wore the FGMS sensors then consumed a standard breakfast. Their glucose levels were subsequently recorded for 2 hours, both by the FGMS and by measuring capillary glucose levels using the glucose oxidase method. The accuracy of the FGMS data was assessed using the accuracy limits stated in ISO 15197:2013.

Results: FGMS measurements were mostly lower than glucose oxidase measurements (mean absolute relative difference ± SD: 25.4 ± 17.0%, p < 0.001). However, the maximum difference from baseline captured by the two methods was not significantly different (mean ± SD, glucose oxidase: 58.5 ± 18.9 mg/dl; FGMS, 54.4 ± 28.9 mg/dl, p = 0.366).

Conclusions: FGMS could track the incremental glycaemic excursions after meals in adults without diabetes, yet further studies with greater sample sizes are needed to confirm this finding.

Objective: Malnutrition among hospital patients, a frequent, yet under-diagnosed problem is associated with adverse impact on patient outcome and health care costs. Development of highly accurate malnutrition screening tools is, therefore, essential for its timely detection, for providing nutritional care, and for addressing the concerns related to the suboptimal predictive value of the conventional screening tools, such as the Malnutrition Universal Screening Tool (MUST). We aimed to develop a machine learning (ML) based classifier (MUST-Plus) for more accurate prediction of malnutrition.

Method: A retrospective cohort with inpatient data consisting of anthropometric, lab biochemistry, clinical data, and demographics from adult (≥ 18 years) admissions at a large tertiary health care system between January 2017 and July 2018 was used. The registered dietitian (RD) nutritional assessments were used as the gold standard outcome label. The cohort was randomly split (70:30) into training and test sets. A random forest model was trained using 10-fold cross-validation on training set, and its predictive performance on test set was compared to MUST.

Results: In all, 13.3% of admissions were associated with malnutrition in the test cohort. MUST-Plus provided 73.07% (95% confidence interval [CI]: 69.61%-76.33%) sensitivity, 76.89% (95% CI: 75.64%-78.11%) specificity, and 83.5% (95% CI: 82.0%-85.0%) area under the receiver operating curve (AUC). Compared to classic MUST, MUST-Plus demonstrated 30% higher sensitivity, 6% higher specificity, and 17% increased AUC.

Conclusions: ML-based MUST-Plus provided superior performance in identifying malnutrition compared to the classic MUST. The tool can be used for improving the operational efficiency of RDs by timely referrals of high-risk patients.

Objective: To assess the effect of beetroot juice (BET) on recovery kinetics of physical performance, muscle damage and perceived muscle soreness after simulated soccer match play in soccer players.

Method: In a randomized, double-blind, crossover design, thirteen soccer players completed the Loughborough Intermittent Shuttle Test LIST. Players received either BET or placebo (PLA) (2*150) for 7 days (3 days pre-exercise, on the day trial, and 3 days post-exercise). Physical performance (Squat jump: SJ, countermovement jump: CMJ, maximal voluntary contraction: MVC, and 20 meters sprint: SP), blood markers of muscle damage (creatine kinase: CK, Lactate dehydrogenase: LDH), inflammatory parameter (C-reactive protein: CRP) and perceived muscle soreness (DOMS) were assessed at baseline, 0 h, 24 h, 48 h and 72 h following the exercise.

Results: Following the LIST, a decrease was observed in CMJ, MVC and SP at 0 h, 24 h, 48 h in both conditions (p < 0.05). However, compared to PLA session, this decrease was significantly attenuated with BET for CMJ at 24 h and at 48 h and for MVC at 0 h, 24 h, 48 h and for SP at 48 h after the LIST (p < 0.05). Likewise, DOMS values were significantly lower with BET compared to PLA condition immediately and at 24 h after exercise.CK, LDH and CRP levels increased at 0 h and at 24 h post exercise in both conditions (p < 0.05), but without any significant difference between the two condition (p > 0.05).

Conclusion: The results of the present study suggest that chronic beetroot juice supplementation reduces post exercise perceived muscle soreness and maintain better performance during the recovery period in soccer players.

Objective: To investigate the feasibility of a modified MCT-based ketogenic diet and its impact on plasma β-hydroxybutyrate and MS outcomes compared to a modified Paleolithic diet and usual diet in people with Multiple Sclerosis (MS).

Methods: Fifteen individuals with MS were randomized to 3 groups: 1) modified Paleolithic diet (Paleo; n = 6); 2) medium-chain triglyceride (MCT)-based ketogenic diet that included coconut as a fat source (Keto; n = 5); or 3) usual diet (Control; n = 4). Participants had blood drawn every 4 weeks to monitor nutritional ketosis. Participants completed 4-day weighed food records, measures of disability, fatigue, quality of life (QoL), cognitive function, and physical function at baseline and 12-weeks.

Results: Macronutrient intake significantly shifted toward a ratio indicative of a ketogenic diet in the Keto group at 12 weeks. Similarly, plasma β-hydroxybutyrate indicated nutritional ketosis in the Keto group, whereas neither macronutrient intake nor plasma β-hydroxybutyrate indicated nutritional ketosis in the Paleo and Control groups. The Paleo group had significant within group reductions in fatigue scores and maintained cognitive function scores compared to the Control group. The Keto group had significant reductions in fasting glucose and insulin compared to baseline values; however, no clinical outcomes significantly changed.

Conclusions: Participants consuming the MCT-based ketogenic diet achieved nutritional ketosis; however, it was not associated with significant clinical improvement in this study whereas the modified Paleolithic diet was associated with significant clinical improvements. Larger randomized controlled trials are needed to determine the safety and efficacy of the modified Paleolithic and MCT-based ketogenic diets on MS.