Journal of the American Nutrition Association最新文献

Objectives: There is no consensus on the ideal frequency of meals for the prevention and treatment of obesity. While some studies have reported that increasing meal frequency might be beneficial in the treatment of obesity due to its positive effects on glycemic regulation, appetite and diet quality, other studies have reported negative effects. In this study, it was aimed to examine the effect of meal frequency on body composition, anthropometric measurements, some of the biochemical parameters and diet quality in overweight/obese adults.

Methods: A total of 91 individuals, all overweight/obese, between the ages of 18-64, including 46 consuming 2 main meals (2MMG) and 45 consuming 3 main meals (3MMG) participated in the study. General characteristics and dietary habits of the individuals were obtained with a questionnaire. A 3-day food consumption record was taken to determine their daily energy and nutrient intake and to evaluate their diet quality with the "Healthy Eating Index 2015". Anthropometric measurements of the individuals were performed, body compositions were analyzed and some blood parameters were evaluated.

Results: The median values of body weight, lean body mass (kg), total body water, basal metabolic rate and hip circumference of men in the 3MMG were found to be higher than men in the 2MMG (p < 0.05). The anthropometric measurements and body composition components of women were similar between the two groups (p > 0.05). The renal urea nitrogen and total cholesterol values of women in 2MMG were higher than those of women in the 3MMG. In the regression analysis, a 1-unit increase in the number of main meals was determined to lead to a 9.3 points increase in the total score of HEI 2015.

Conclusions: Regular consumption of main meals may have positive effects on diet quality, some of the biochemical parameters, basal metabolic rate and body composition in overweight/obese adults. In this group, which is known to have incorrect food preferences in general, it is important to plan the number of meals and the content of these meals correctly.

Objectives: The objective of this study was to examine the difference between the extent of muscle damaging exercise on muscle function variables of vegans and omnivores.

Methods: Twenty recreationally trained participants completed the study. Participants were assigned to either vegan (n = 10) or omnivore (n = 10) groups. Subjects completed a consent visit followed by 2 visits consisting of running exercise sessions and test familiarization. They returned to the laboratory for visit 4 3-5 days after visit 3 to complete the testing battery. Following the testing, the participants performed a downhill run on the treadmill at -15% grade and approximately 70% of their speed at VO2peak and repeated the testing battery upon completion. Participants were asked to track their food intake. Visits 5, 6, and 7 took place 24, 48, and 72 h following the downhill running protocol, respectively, and consisted of the same testing battery used during visit 4. The detection of differences was performed using two-way (group x time) mixed factorial ANOVA with repeated measures.

Results: No group x time interactions were noted for running economy or any of the dependent variables. Main effects of time were found for muscle thickness (p<.001) with small effect sizes (d=-0.194 to d=-0.265), pain pressure threshold (p=.002) with medium effect sizes (d=.460 to d=.461), NPRS scale (p<.001) with large effect sizes (d = -0.776 to d=-1.520), and jump height (p<.002) with small to medium effect sizes (d=.304 to d=.438). Nutritional analysis compared the two groups revealed no difference (p>.05) between relative intake of macronutrients and that both exceeded typical recommendations for protein (vegan group - 1.4 g/kg, omnivore group - 1.6 g/kg).

Conclusion: The lack of differences in recovery between the groups suggests that nutritional adequacy may play a role in recovery. Recovery from downhill running might be influenced by several factors beyond diet, such as exercise protocol intensity, individual fitness levels, and age.

Objective: There is evidence showing the effect of hypocaloric diet and increasing physical activity on weight loss. However, the effect of these factors on body composition and functional capacity remains unclear. Also, it is not clear which type of exercise (aerobic, resistance) has effective health benefits for men who are overweight. The aim of this study is to investigate whether a 12-week combined exercise or walking intervention combined with a hypocaloric diet provides improvements in body composition and functional capacity of men who are overweight compared to those who do not exercise.

Methods: 60 healthy adult men who are overweight were randomized and divided into 3 groups: 1: Hypocaloric Diet + Combined Exercise; 2: Hypocaloric Diet + Walking; 3: Hypocaloric Diet. The exercise groups were trained for 12 wk, 3 days a week and 60 min (60 min3 days12 wk). Body composition was determined with Bioelectrical Impedance Analysis (BIA) device, strength parameters with MicroFet 2, functional capacity with 6-min walking test.

Results: Improvement was observed in all groups at the end of 12 wk. The greatest improvement was in the combined exercise group. While the values of the combined exercise group increased in Skeletal Muscle Mass, there was a decline in the walking and non-exercising group. Basal Metabolism was maintained in combined exercise, but a decrease occurred in the non-exercising group. Muscle force increased in combined exercise; however, it was maintained in the legs in the walking group. Cardiorespiratory fitness was at best level in walking group, but there was no difference between combined exercise.

Conclusions: As a result, a hypocaloric diet without an exercise prescription is sufficient to lose weight in the short term (12 wk) at a certain level. But exercise is more important for body composition, weight management and functional capacity. Long-term and in-depth studies should be conducted to interpret the results better.

Objective: Chocolate is a popular food that may affect the activity of the autonomic nervous system (ANS). The aim of this study was to determine the effect of a single dose of dark or milk chocolate on ANS cardiac control during rest and mental stress induced by the Stroop test (ST).

Methods: Healthy participants, divided into DARK or MILK chocolate groups, ingested corresponding type of chocolate (1 g/kg body weight). They underwent measurement of ANS during relaxation and ST before and 2 h after chocolate consumption. ANS control was assessed by determination of heart rate (HR) and heart rate variability using parameters related to complex autonomic modulation (TP, SDNN) or primary vagal modulation (HFnu, RMSSD).

Results: HR was always increased during ST in both groups. Relaxation HR values after chocolate ingestion were higher only in the DARK chocolate group. During ST, values of TP, SDNN and HFnu decreased before and after chocolate ingestion in the DARK group, but only before chocolate ingestion in the MILK group. RMSSD values decreased during ST before and after chocolate ingestion in both groups. Relaxation TP, RMSSD and HFnu values after chocolate ingestion were lower in the DARK but not in the MILK group.

Conclusion: The results suggest that even a single dose of milk chocolate attenuates changes in ANS cardiac control induced by mental stress, whereas a single dose of dark chocolate has an activating effect on the heart via modification of ANS cardiac control at rest. Different levels of sugars and cocoa biologically active compounds in the two types of chocolate could explain the observed effects.

Objective: Prevention and improvement of hypertension is one of the most important health issues worldwide. The traditional Japanese diet contributes to the prevention of some non-communicable diseases associated with hypertension. However, whether traditional Japanese dietary patterns are associated with hypertension prevalence and systolic blood pressure (SBP) worldwide remains unknown. In this study, we aimed to investigate whether the traditional Japanese diet score (TJDS) is associated with hypertension prevalence and SBP.

Methods: This cross-sectional and longitudinal ecological study from 2009 to 2019 included 141 countries with a population of at least 1 million. All data used for analysis were obtained from internationally available databases. The TJDS was calculated using country-specific supplies of five foods commonly eaten in the traditional Japanese diet (rice, fish, soybean, vegetables, and egg) and three less commonly eaten foods (wheat, milk, and red meat). Hypertension was defined by SBP ≥140 mmHg, diastolic blood pressure ≥90 mmHg, or use of antihypertensive medications. The mean SBP was >25 age-standardized data. A general linear model was used for the cross-sectional model in 2009, and a linear mixed model was used for the longitudinal analysis from 2009 to 2019. The covariates included gross domestic product, percentage of population aged >65 years, years of education, smoking rate, average body mass index, physical activity, and energy supply.

Results: The TJDS was negatively associated with hypertension prevalence (β ± standard error: -0.861 ± 0.202, p < 0.001) and SBP (β ± standard error: -0.364 ± 0.154, p < 0.05) in the cross-sectional analysis. The TJDS was significantly negatively associated with hypertension prevalence (β ± standard error: -0.845 ± 0.200, p < 0.001) and SBP (β ± standard error: -0.312 ± 0.149, p < 0.05) in the 10-year longitudinal analysis controlled for full covariables.

Conclusions: Traditional Japanese dietary patterns are associated with lower hypertension prevalence and SBP worldwide.

Objective: Obesity is often accompanied by insulin resistance (IR) and diabetes. We explored the association between vitamin D levels and IR in non-diabetic obesity.

Methods: We conducted a cross-sectional study based on the data of National Health and Nutrition Examination Survey (NHANES) from 2001 to 2018. Non-diabetic individuals (aged ≥20 years) with obesity (BMI ≥ 30kg/m²) were included in the study. And HOMA-IR ≥ 2.5 was defined as IR. The multivariable linear regression models were constructed to evaluate the associations between levels of 25(OH)D and HOMA-IR. We calculated the odds ratio (OR) and 95% confidential intervals (CIs) for associations between 25(OH)D deficiency and IR in obesity using multivariable logistic regression models.

Results: Overall, a total of 3887 individuals were included in this study. Serum vitamin D level was significant lower in obesity participants with IR than that of non-IRs. The linear regression models showed that vitamin D level was inversely associated with HOMA-IR in obesity after adjusting for covariables (β=-0.15, 95%CI (-0.28, -0.02), p = 0.028). And the multivariable logistic regression models indicated an association between vitamin D deficiency and IR in obesity ((OR= 1.38, 95%CI (1.09-1.73), p = 0.007)). The further stratified regression analyses among different BMI demonstrated that vitamin D deficiency (OR = 1.4, 95%CI (1.05,1.86), p = 0.022) only contributed to developing IR in class I obesity.

Conclusion: This study suggested an association of vitamin D levels with IR in obesity. And vitamin D deficiency contributed to IR in class I obesity.

Objective: To investigate the acute effects of ingesting a beverage containing guarana (Paullinia cupana) seed powder on performance during field tests related to physical capacities that are determinants of soccer performance, such as lower limb power, sprint, agility, and the capacity to carry out intermittent exercise.

Methods: The study was conducted using a randomized, crossover, and counterbalanced design, with a beverage containing guarana or placebo administered in a double-blind manner. Twenty-seven under-17 soccer players of a professional soccer club performed a battery of tests 60 min after the ingestion of guarana (3 g of the fruit seed powder) or placebo. Trials were performed with a 7-day washout period. The battery of tests included a countermovement jump test, sprints of 10 and 20 m, an Illinois agility test, and a Yo-Yo Intermittent Recovery Test level 1 (YYIR1).

Results: Guarana ingestion did not improve countermovement jump, sprints, or agility (p > 0.05). However, guarana ingestion increased the distance covered in the YYIR1, compared with placebo ingestion (p = 0.01).

Conclusion: Acute ingestion of guarana improves the capacity to perform intermittent exercise in soccer players but seems to be ineffective to improve lower limb power, sprint, and agility.

Background: Anxiety symptoms are factors that directly affect eating habits, but this interference can be heterogeneous depending on the nutritional status of the individuals.

Objectives: To analyze whether the presence of anxiety symptoms at the beginning of the pandemic influenced the change in food consumption according to its purpose and extent of processing during a one-year follow-up and whether this association occurs equally with excess weight and without excess weight university students.

Methods: This longitudinal study was carried out with 583 university students from a public Higher Education Institution (HEI) in Brazil. The Generalized Estimating Equation (GEE) was used to verify whether anxiety symptoms were associated with changes in food consumption over time.

Results: The results showed that previous moderate/severe anxiety symptoms were associated with an increased frequency of consumption of both fresh or minimally processed foods (β: 0.2 95%CI: 0.1; 0.7 p = 0.013) and ultra-processed foods (β: 5.6 95%CI: 1.8; 17.7 p = 0.003), but with different magnitudes. In university students who were not excess weight, previous moderate/severe anxiety symptoms were associated with a reduction in the frequency of consumption of fresh or minimally processed foods (β: -2.0 95%CI: -3.5; -0.5 p = 0.008), while in those who were excess weight, there was an increase in consumption of ultra-processed foods (β: 4.5 95%CI: 2.2; 6.8 p < 0.001).

Conclusion: This study confirms the influence of anxiety symptoms on food consumption according to the extent and purpose of processing. In addition, these results emphasize the role of psychological distress in the university population, and that this factor can affect excess weight and without excess weight individuals differently.

Objective: Our aim in this study is, does 29-day regular consumption of Pleurotus ostreatus water extract by volunteer individuals who meet the study criteria have an effect on blood and cytokine values?

Method: In accordance with the purpose of the study, volunteers were asked to consume 100 ml of the extract every morning for 29 days. Three tubes of blood samples were taken from the volunteers on the 15th and 29th days of the study. Biochemical and hematological analysis of the blood samples were performed and immunomodulatory effects through cytokines were examined. The values obtained from 3 tubes of blood obtained from volunteers before the use of mushroom extract were used as control. The chemical composition and β-glucan content of 100 ml of mushroom water extract were also analyzed.

Result: IL-4, IL-6, IL-10 and IL-13 could not be detected because the values were below the lowest standard value. TNF-α, IFN-γ and IL-1β 15th and 29th day values decreased compared to the 1st day (control) values (p < 0.05). However, there was no significant difference observed between the 15th and 29th day. No abnormalities were observed in biochemical and hematological values. Also, the β-glucan content of extract was found 38.12 mg/100 ml.

Conclusion: The frequency range of kidney and liver function test results confirmed that P. osreatus is a reliable food source. Considering the cytokine values these results indicate that P. ostreatus water extract has an anti-inflammatory effect. As no significant difference was observed in 29 days of use, it is thought that 15 days of daily consumption of the extract may be sufficient for the anti-inflammatory effect to occur. However, a large number of qualified clinical trials are needed to support the issue.

Objective: The aim was to identify trajectory patterns of weight and length in children from birth until two years of life and establish associations with maternal and child characteristics.

Methods: A mixed-cohort study was conducted in public health services in Colombo-PR, Brazil, between 2018 and 2022. Pregnancy information was gathered through anthropometric data collection and questionnaires. Birth data were extracted from birth record forms, while weight and length data in the first two years of life were obtained from physical and electronic health service records. Weight and length trajectory patterns were identified using a group-based trajectory model. The definition of the number of trajectory patterns to be selected considered the model fit to the type of variable, its practical utility, as well as the probabilities of group membership.

Results: Two trajectory patterns of weight and length were identified among the children. The majority exhibited a pattern of weight (67.8%, n = 382) and length (90.9%, n = 472) considered high and stable, with a tendency to decelerate from one and a half years of age. The probability of belonging to the lower weight gain group was associated with female sex (41.5%, p < 0.001), smoking during pregnancy (48.7%, p = 0.008), prematurity (65.0%, p = 0.001), cesarean delivery (36.4%, p = 0.009), small for gestational age (69.0%, p < 0.001), and twinning (69.2%, p = 0.002). Similarly, the probability of belonging to the lower length gain group was associated with female sex (11.7%, p < 0.001), smoking during pregnancy (20.6%, p = 0.003), cesarean delivery (10.1%, p = 0.048), born small for gestational age (46.4%, p < 0.001), and twinning (46.1%, p < 0.001).

Conclusion: Conditions during pregnancy and childbirth can impact growth patterns in the first two years of life.