Comparative effectiveness of single foods and food groups on body weight: a systematic review and network meta-analysis of 152 randomized controlled trials

Physical Activity and Excess Body Weight and Adiposity for Adults. American College of Sports Medicine Consensus Statement

ABSTRACT

Excessive body weight and adiposity contribute to many adverse health concerns. The American College of Sports Medicine (ACSM) recognizes that the condition of excess body weight and adiposity is complex, with numerous factors warranting consideration. The ACSM published a position stand on this topic in 2001 with an update in 2009, and a consensus paper on the role of physical activity in the prevention of weight gain in 2019. This current consensus paper serves as an additional update to those prior ACSM position and consensus papers. The ACSM supports the inclusion of physical activity in medical treatments (pharmacotherapy, metabolic and bariatric surgery) of excess weight and adiposity, as deemed to be medically appropriate, and provides perspectives on physical activity within these therapies. For weight loss and prevention of weight gain, the effects may be most prevalent when physical activity is progressed in an appropriate manner to at least 150 min·wk-1 of moderate-intensity physical activity, and these benefits occur in a dose-response manner. High-intensity interval training does not appear to be superior to moderate-to-vigorous physical activity for body weight regulation, and light-intensity physical activity may also be an alternative approach provided it is of sufficient energy expenditure. Evidence does not support that any one single mode of physical activity is superior to other modes for the prevention of weight gain or weight loss, and to elicit holistic health benefits beyond the effects on body weight and adiposity, multimodal physical activity should be recommended. The interaction between energy expenditure and energy intake is complex, and the effects of exercise on the control of appetite are variable between individuals. Physical activity interventions should be inclusive and tailored for sex, self-identified gender, race, ethnicity, socioeconomic status, age, and developmental level. Intervention approaches can also include different forms, channels, and methods to support physical activity.

Development and Validation of the Meiji Nutritional Profiling System per Serving Size

Serving size may be the appropriate reference for calculating food nutritional value. We aimed to assess the nutritional values of Japanese foods based on serving sizes rather than per 100 g by adapting the Meiji Nutritional Profiling System (Meiji NPS). Given the variability in serving sizes across countries, we used Japanese serving sizes to calculate the Meiji NPS scores. We confirmed the convergent validity of the Meiji NPS scores per serving size with the Nutrient-Rich Food Index 9.3 using Spearman's correlation coefficients (r = 0.51, p < 0.001). Food groups recommended by official guidelines, such as pulses, nuts and seeds, fish and seafood, fruits, vegetables, and milk and milk products, scored relatively high. Furthermore, the nutrient density scores of food items with small serving sizes, such as mushrooms, algae, seasonings, and fats and oils, were moderated when calculated by per serving size, despite having considerably higher or lower scores per 100 g. These results indicate that calculating NPS per serving size allows for the assessment of the nutritional value of food items in accordance with actual consumption quantities. Therefore, the Meiji NPS calculated per serving size, alongside the per 100 g version, may be useful for dietary management depending on specific purposes.

Effect of Nuts on Anthropometric and Glycemic Indexes and Blood Pressure in Secondary Cardiovascular Prevention: A Systematic Review and Meta-analysis of Randomized Controlled Trials

CONTEXT

Nut-enriched diets have a positive impact on cardiovascular risk factors, such as body mass, blood pressure, and fasting blood glucose. However, studies in individuals undergoing secondary cardiovascular prevention show controversial results.

OBJECTIVE

This systematic review with meta-analysis assessed the effect of nut supplementation on anthropometric, glycemic, and blood pressure indices in patients with atherosclerotic cardiovascular disease, as well as the frequency of adverse events.

DATA SOURCES

Six databases were used for the search-PubMed, Cochrane Library, EMBASE, BVS (Biblioteca Virtual da Saude), Web of Science, and ClinicalTrials.gov-until February 2023, with no language restrictions.

DATA EXTRACTION

The Cochrane Handbook for Systematic Reviews of Interventions methodology and the PICOS (Population, Intervention, Comparison, Outcome, Setting/design) strategy were used. Seven independent reviewers were involved in data extraction and resolution of disagreements. Certainty of the evidence was evaluated using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system.

DATA ANALYSIS

From 5187 records identified, 6 publications containing data referring to 5 randomized clinical trials (n = 436) were included in the final analyses. The nuts evaluated were almonds, pecans, Brazil nuts, and mixed nuts, with portions that varied between 5 g and 85 g (median: 30 g/day). The intervention period varied between 6 and 12 weeks. The nuts had no effect on fasting glucose and anthropometric indices, although the certainty of the evidence for most of these outcomes was low or very low. They also had no effect on systolic (mean difference [MD]: -1.16 mmHg [95% CI, -5.68 to 3.35], I2 = 0%-moderate certainty of evidence) or diastolic (MD: 0.10 mmHg [95% CI, -2.30 to 2.51], I2 = 0%-high certainty of evidence) blood pressure. It was not possible to aggregate data on adverse events.

CONCLUSION

Nut supplementation had no effect on blood pressure, fasting glucose, or anthropometric profile in the context of atherosclerotic cardiovascular disease.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42020163456.

Impact of dietary carbohydrate, fat or protein restriction on the human gut microbiome: a systematic review

Restriction of dietary carbohydrates, fat and/or protein is often used to reduce body weight and/or treat (metabolic) diseases. Since diet is a key modulator of the human gut microbiome, which plays an important role in health and disease, this review aims to provide an overview of current knowledge of the effects of macronutrient-restricted diets on gut microbial composition and metabolites. A structured search strategy was performed in several databases. After screening for inclusion and exclusion criteria, thirty-six articles could be included. Data are included in the results only when supported by at least three independent studies to enhance the reliability of our conclusions. Low-carbohydrate (<30 energy%) diets tended to induce a decrease in the relative abundance of several health-promoting bacteria, including Bifidobacterium, as well as a reduction in short-chain fatty acid (SCFA) levels in faeces. In contrast, low-fat diets (<30 energy%) increased alpha diversity, faecal SCFA levels and abundance of some beneficial bacteria, including Faecalibacterium prausnitzii. There were insufficient data to draw conclusions concerning the effects of low-protein (<10 energy%) diets on gut microbiota. Although the data of included studies unveil possible benefits of low-fat and potential drawbacks of low-carbohydrate diets for human gut microbiota, the diversity in study designs made it difficult to draw firm conclusions. Using a more uniform methodology in design, sample processing and sharing raw sequence data could foster our understanding of the effects of macronutrient restriction on gut microbiota composition and metabolic dynamics relevant to health. This systematic review was registered at https://www.crd.york.ac.uk/prospero as CRD42020156929.

Development and Validation of the Meiji Nutritional Profiling System (Meiji NPS) to Address Dietary Needs of Adults and Older Adults in Japan

This study introduces the Meiji Nutritional Profiling System (Meiji NPS), which was specifically designed to respond to age-related shifts in nutrient requirements among Japanese adults (<65 years old) and older adults (≥65 years old). Japan has one of the most aged societies in the world. The health issues of interest are malnutrition and lifestyle-related diseases among adults and frailty among older adults. Two versions of the NPS were developed based on nutrients to encourage (protein, dietary fibers, calcium, iron, and vitamin D), food groups to encourage (fruits, vegetables, nuts, legumes, and dairy), and nutrients to limit (energy, saturated fatty acids, sugars, and salt equivalents). The Meiji NPS for older adults did not include iron or saturated fatty acids. The algorithms were based on the Nutrient-Rich Foods Index (NRF). The convergent validity between the Meiji NPS and the existing NPSs for the same foods was confirmed using Spearman's correlation coefficients (NRF: r = 0.67 for adults and r = 0.60 for older adults; Health Star Rating: r = 0.64 for adults and r = 0.61 for older adults). The Meiji NPS may be useful for nutritional evaluation and reformulation of food products, tailored to adults and older adults to ameliorate health issues in Japan.

The effect of expectancy versus actual gluten intake on gastrointestinal and extra-intestinal symptoms in non-coeliac gluten sensitivity: a randomised, double-blind, placebo-controlled, international, multicentre study

BACKGROUND

Many individuals without coeliac disease or wheat allergy reduce their gluten intake because they believe that gluten causes their gastrointestinal symptoms. Symptoms could be affected by negative expectancy. Therefore, we aimed to investigate the effects of expectancy versus actual gluten intake on symptoms in people with non-coeliac gluten sensitivity (NCGS).

METHODS

This randomised, double-blind, placebo-controlled, international, multicentre study was done at the University of Leeds (Leeds, UK), Maastricht University (Maastricht, the Netherlands), and Wageningen University and Research (Wageningen, the Netherlands). People aged 18-70 years with self-reported NCGS (ie, gastrointestinal symptoms within 8 h of gluten consumption) without coeliac disease and wheat allergy were recruited. Participants had to follow a gluten-free or gluten-restricted diet for at least 1 week before (and throughout) study participation and had to be asymptomatic or mildly symptomatic (overall gastrointestinal symptom score ≤30 mm on the Visual Analogue Scale [VAS]) while on the diet. Participants were randomly assigned (1:1:1:1; blocks of eight; stratified by site and gender) to one of four groups based on the expectation to consume gluten-containing (E+) or gluten-free (E-) oat bread for breakfast and lunch (two slices each) and actual intake of gluten-containing (G+) or gluten-free (G-) oat bread. Participants, investigators, and those assessing outcomes were masked to the actual gluten assignment, and participants were also masked to the expectancy part of the study. The primary outcome was overall gastrointestinal symptom score on the VAS, which was measured at and corrected for baseline (before breakfast) and hourly for 8 h, with lunch served after 4 h, and analysed per-protocol. Safety analysis included all participants incorporated in the per-protocol analysis. The study is registered at ClinicalTrials.gov, NCT05779358, and has ended.

FINDINGS

Between Oct 19, 2018, and Feb 14, 2022, 165 people were screened and 84 were randomly assigned to E+G+ (n=21), E+G- (n=21), E-G+ (n=20), or E-G- (n=22). One person in the E+G+ group was excluded due to not following test day instructions, leaving 83 participants in the per-protocol analysis. Median age was 27·0 years (IQR 21·0-45·0), 71 (86%) of 83 people were women, and 12 (14%) were men. Mean overall gastrointestinal symptom score was significantly higher for E+G+ (16·6 mm [95% CI 13·1 to 20·0]) than for E-G+ (6·9 mm [3·5 to 10·4]; difference 9·6 mm [95% CI 3·0 to 16·2], p=0·0010) and E-G- (7·4 mm [4·2 to 10·7]; difference 9·1 mm [2·7 to 15·6], p=0·0016), but not for E+G- (11·7 mm [8·3 to 15·1]; difference 4·9 mm [-1·7 to 11·5], p=0·28). There was no difference between E+G- and E-G+ (difference 4·7 mm [-1·8 to 11·3], p=0·33), E+G- and E-G- (difference 4·2 mm [-2·2 to 10·7], p=0·47), and E-G+ and E-G- (difference -0·5 mm [-7·0 to 5·9], p=1·0). Adverse events were reported by two participants in the E+G- group (itching jaw [n=1]; feeling lightheaded and stomach rumbling [n=1]) and one participant in the E-G+ group (vomiting).

INTERPRETATION

The combination of expectancy and actual gluten intake had the largest effect on gastrointestinal symptoms, reflecting a nocebo effect, although an additional effect of gluten cannot be ruled out. Our results necessitate further research into the possible involvement of the gut-brain interaction in NCGS.

FUNDING

Government of the Netherlands Topsector Agri & Food Top Consortium for Knowledge and Innovation, AB Mauri Global Bakery Ingredients, Baking Industry Research Trust, Borgesius-Albert Heijn, CSM Innovation Centre, the International Maize and Wheat Improvement Center (CIMMYT), DSM Food Specialties, Fazer, Healthgrain Forum, the International Association for Cereal Science and Technology, the International Wheat Gluten Association, Lantmännen, Mondelez International, Nederlands Bakkerij Centrum, Nutrition & Santé, Puratos, Rademaker, Sonneveld Group, and Zeelandia HJ Doeleman.

Higher Imported Food Patterns Are Associated with Obesity and Severe Obesity in Tuvalu: A Latent Class Analysis

Background

Tuvalu is a Pacific Island country within the small island developing states that has observed a significant and alarming increase in obesity rates over the past 40 years, affecting ∼60 %-70 % of the current population.

Objectives

This study aimed to investigate the association between food patterns and the proportion of obesity in a Pacific Island country.

Methods

The 2022 COMmunity-based Behavior and Attitude survey in Tuvalu (COMBAT) included 985 adults with complete data on sociodemographic information and the frequency of consumption of 25 common foods. A latent class analysis determined 4 food patterns. Bayesian multilevel logistic and linear regression models estimated the association between food patterns and the proportion of obesity [body mass index (BMI) ≥30 kg/m2], severe obesity (BMI ≥40 kg/m2), and weight (kg), adjusting for potential confounders and accounting for clustering by region.

Results

The latent class analysis revealed 4 food patterns with an entropy of 0.94 and an average posterior probability of class assignment for each individual of 0.97, described as follows: 1) local: locally produced foods with moderate food diversity (proportion of individuals = 28 %); 2) diverse-local: local with greater food diversity (17 %); 3) restricted-imported: more imported with restricted diversity (29 %); and 4) imported: heavily imported with high diversity (26 %). Compared to those following the diverse-local pattern, the odds of having obesity were greater for those classified with the imported pattern [odds ratio (OR): 2.52; 95 % credible interval (CrI): 1.59, 3.99], restricted-imported pattern (OR: 1.89; 95 % CrI: 1.59, 3.99), and local pattern (OR: 1.54; 95 % CrI: 0.94, 2.50). Similar trends were observed for severe obesity while body weight was positively associated with both restricted-imported and imported food patterns.

Conclusions

The high consumption of imported foods, together with the low consumption of plant-based foods and protein-rich foods, could be a relevant modifiable lifestyle factor explaining the high levels of obesity and severe obesity in Tuvalu, a Pacific Island country.