Diet quality of vegetarian diets compared with nonvegetarian diets: a systematic review

Plant-based and Early Time-restricted Eating for Prevention and Treatment of Type 2 Diabetes in Adults: A Narrative Review

Type 2 diabetes (T2D) is a significant public health challenge for which effective lifestyle interventions are needed. A growing body of evidence supports the use of both plant-based eating patterns and early time-restricted eating (eTRE) for the prevention and treatment of T2D, but research has not yet explored the potential of these dietary strategies in combination. In this narrative review, we assessed the evidence by which plant-based diets, in conjunction with eTRE, could support T2D care. The electronic databases MEDLINE and the Web of Science were searched for relevant articles published throughout the last decade. Observational research has shown that healthy plant-based eating patterns and eTRE are associated with reductions in T2D risk. Interventional trials demonstrated that plant-based diets promote improvements in glycated hemoglobin, insulin resistance, glycemic management, and cardiometabolic risk factors. These changes may be mediated, in part, by reductions in oxidative stress, dietary acid load, and hepatocellular and intramyocellular lipids. The eTRE strategies were also shown to improve insulin resistance and glycemic management, and mechanisms of action included enhanced regulation of circadian rhythm and increased metabolic flexibility. Integrating these dietary strategies may produce additive benefits, mediated by reduced visceral adiposity and beneficial shifts in gut microbiota composition. However, potential barriers to concurrent implementation of these interventions may exist, including social challenges, scheduling constraints, and tolerance. Prospective trials are needed to examine their acceptability and clinical effects.

Development of the VEGANScreener, a Tool for a Quick Diet Quality Assessment among Vegans in Europe

BACKGROUND

Plant-based diets are not inherently healthy. Similar to omnivorous diets, they may contain excessive amounts of sugar, sodium, and saturated fats, or lack diversity. Moreover, vegans might be at risk of inadequate intake of certain vitamins and minerals commonly found in foods that they avoid. We developed the VEGANScreener, a tool designed to assess the diet quality of vegans in Europe.

METHODS

Our approach combined best practices in developing diet quality metrics with scale development approaches and involved the following: (a) narrative literature synthesis, (b) evidence evaluation by an international panel of experts, and (c) translation of evidence into a diet screener. We employed a modified Delphi technique to gather opinions from an international expert panel.

RESULTS

Twenty-five experts in the fields of nutrition, epidemiology, preventive medicine, and diet assessment participated in the first round, and nineteen participated in the subsequent round. Initially, these experts provided feedback on a pool of 38 proposed items from the literature review. Consequently, 35 revised items, with 17 having multiple versions, were suggested for further consideration. In the second round, 29 items were retained, and any residual issues were addressed in the final consensus meeting. The ultimate screener draft encompassed 29 questions, with 17 focusing on foods and nutrients to promote, and 12 addressing foods and nutrients to limit. The screener contained 24 food-based and 5 nutrient-based questions.

CONCLUSIONS

We elucidated the development process of the VEGANScreener, a novel diet quality screener for vegans. Future endeavors involve contrasting the VEGANScreener against benchmark diet assessment methodologies and nutritional biomarkers and testing its acceptance. Once validated, this instrument holds potential for deployment as a self-assessment application for vegans and as a preliminary dietary screening and counseling tool in healthcare settings.

Human gut microbiome, diet, and mental disorders

Diet is one of the most important external factor shaping the composition and metabolic activities of the gut microbiome. The gut microbiome plays a crucial role in host health, including immune system development, nutrients metabolism, and the synthesis of bioactive molecules. In addition, the gut microbiome has been described as critical for the development of several mental disorders. Nutritional psychiatry is an emerging field of research that may provide a link between diet, microbial function, and brain health. In this study, we have reviewed the influence of different diet types, such as Western, Mediterranean, vegetarian, and ketogenic, on the gut microbiota composition and function, and their implication in various neuropsychiatric and psychological disorders.

A Therapeutic Approach in the Management of Chronic Kidney Disease: Plant-Based Dietary Models and Associated Parameters

PURPOSE OF REVIEW

Chronic kidney disease is one of the leading causes of death worldwide today. Nutrition and nutrition-related factors have a very important role in both the prevention and management of the disease. Plant-based dietary practices are one of the promising approaches to chronic kidney disease. This review aims to examine the potential benefits and risks of plant-based diet models on symptoms and indices used in diet quality in chronic kidney disease.

RECENT FINDINGS

Recently, a growing body of evidence has shown that, unlike animal-based diets, diets rich in plant-based nutrients may play an active role in the incidence of chronic kidney disease in many ways and the management of common symptoms, such as metabolic acidosis, uremic toxicity, and hyperphosphatemia. Implementation of existing plant-based dietary patterns in patients with chronic kidney disease may increase the efficacy of the diet and improve patients' quality of life by expanding their food choices. While there are concerns about creatine deficiency, dietary adequacy, and accessibility regarding plant-based diets, available information is limited.

Reducing meat and/or dairy consumption in adults: a systematic review and meta-analysis of effects on protein intake, anthropometric values, and body composition

CONTEXT

Consumers are increasingly encouraged to reduce meat and dairy consumption. However, few meta-analyses of randomized controlled trials (RCTs) on the effect of reducing meat and/or dairy on (absolute) protein intake, anthropometric values, and body composition are available.

OBJECTIVE

The aim of this systematic review and meta-analysis was to evaluate the effect of reducing meat and/or dairy consumption on (absolute) protein intake, anthropometric values, and body composition in adults aged ≥ 45 years.

DATA SOURCES

The MEDLINE, Cochrane CENTRAL, Embase, ClinicalTrials.gov, and International Clinical Trials Registry Platform databases were searched up to November 24, 2021.

DATA EXTRACTION

Randomized controlled trials reporting protein intake, anthropometric values, and body composition were included.

DATA ANALYSIS

Data were pooled using random-effects models and expressed as the mean difference (MD) with 95%CI. Heterogeneity was assessed and quantified using Cochran's Q and I2 statistics. In total, 19 RCTs with a median duration of 12 weeks (range, 4-24 weeks) and a total enrollment of 1475 participants were included. Participants who consumed meat- and/or dairy-reduced diets had a significantly lower protein intake than those who consumed control diets (9 RCTs; MD, -14 g/d; 95%CI, -20 to -8; I2 = 81%). Reducing meat and/or dairy consumption had no significant effect on body weight (14 RCTs; MD, -1.2 kg; 95%CI, -3 to 0.7; I2 = 12%), body mass index (13 RCTs; MD, -0.3 kg/m2; 95%CI, -1 to 0.4; I2 = 34%), waist circumference (9 RCTs; MD, -0.5 cm; 95%CI, -2.1 to 1.1; I2 = 26%), amount of body fat (8 RCTs; MD, -1.0 kg; 95%CI, -3.0 to 1.0; I2 = 48%), or lean body mass (9 RCTs; MD, -0.4 kg; 95%CI, -1.5 to 0.7; I2 = 0%).

CONCLUSION

Reduction of meat and/or dairy appears to reduce protein intake. There is no evidence of a significant impact on anthropometric values or body composition. More long-term intervention studies with defined amounts of meat and dairy are needed to investigate the long-term effects on nutrient intakes and health outcomes.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42020207325.

Adherence to a culturally adapted soul food vegan diet among African American adults increases diet quality compared to an omnivorous diet in the NEW Soul Study

Adherence to a vegan diet may lower risk of cardiovascular disease among African Americans (AAs). Feasibility and sustainability of adopting a vegan diet may be challenging among AAs who live in regions where soul food is a predominant cuisine. Our hypothesis was that AAs randomized to a culturally adapted vegan diet will have greater adherence to their assigned diet compared with those randomized to a culturally adapted omnivorous diet. AAs (N = 113) with overweight/obesity from South Carolina were included. Dietary intake was measured at months 0, 3, 6, and 12 using 24-hour recalls. Adherence was defined based on recommended animal product intake for each group. Differences in nutrient intakes and dietary indices (Alternative Healthy Eating Index 2010 and healthy plant-based diet index) between groups were evaluated using t-tests. At 12 months, adherence was higher to the vegan (51%) versus omnivorous (35%) diet. Participants assigned to the vegan diet had higher intake of carbohydrates (P = .01) and fiber (P < .001), and lower intake of cholesterol P< .001) and protein (P = .001) compared with participants assigned to the omnivorous diet. Participants adherent to the vegan diet had lower cholesterol intake (P < .001) and higher fiber intake (P = .02) compared with those adherent to the omnivorous diet. Compared with those assigned to the omnivorous diet, participants assigned to the vegan diet had higher Alternative Healthy Eating Index 2010 (P = .01) and healthy plant-based diet index (P < .001) scores. AAs with overweight/obesity were more adherent to a culturally adapted vegan diet versus an omnivorous diet after 1 year, and nutrient and food group intake changes were sustained.

Consumption Trends and Eating Context of Lentils and Dried Peas in the United States: A Nationally Representative Study

BACKGROUND

Incorporation of lentils and dried peas could form the basis of a nutrient-rich diet; yet, they are among the least-consumed legumes in the United States (US). The objective of this study was to examine the prevalence of lentils/dried peas consumption in the US over time and across socio-demographic groups, as well as to examine the eating context of these foods.

METHODS

Analyses included adults (aged 18 years or older) and children (aged 3-17 years) participating in National Health and Nutrition Examination Survey (NHANES) 2003-2004 through 2017-2018. Participants consuming lentils/dried peas on one or both of the 24-h dietary recalls were categorized as consumers.

RESULTS

Although an increasing time trend in prevalence of consumption was observed over the study period, prevalence of lentils/dried peas consumption was less than 7% in NHANES 2017-2018 in adults and children. Demographic differences were observed, such that a greater proportion of non-Hispanic Asians were classified as consumers. Lentils/dried peas were primarily obtained from grocery stores and supermarkets.

CONCLUSIONS

Although there are signs of rising acceptance of dried peas and lentils, the low prevalence of lentils/dried peas consumption suggests that understanding barriers to consumption of these foods could further identify opportunities to improve their consumption.

Plant-Based Diets and Metabolic Syndrome Components: The Questions That Still Need to Be Answered-A Narrative Review

Metabolic syndrome (MetS) is defined as the co-occurrence of at least three of the following metabolic disorders: abdominal obesity, hypertriglyceridemia, low high-density lipoprotein cholesterol (HDL-C), high blood glucose, and hypertension. The treatment of MetS involves lifestyle changes, including following an appropriate diet. In addition to weight reduction, it is crucial to search for optimal nutritional patterns that are highly effective in optimizing other MetS markers, such as glucose and lipid metabolism, and reducing blood pressure. To date, the effects of a Mediterranean diet and Dietary Approaches to Stop Hypertension (DASH) diet on MetS have been extensively evaluated. Recent epidemiological studies suggest that plant-based diets (PBDs) may be effective in treating MetS; however, there is still a lack of experimental data. This review aims to analyze the potential benefits of different PBDs on MetS determinants based on the available studies. The findings may help personalize dietary interventions and improve patient care for those with MetS.

Ultra-processing markers are more prevalent in plant-based meat products as compared to their meat-based counterparts in a German food market analysis

OBJECTIVE

To compare ultra-processing markers and nutrient composition in plant-based meat products (PBMP) with equivalent meat-based products (MBP).

DESIGN

A total of 282 PBMP and 149 MBP within 18 product categories were assessed. Based on the NOVA classification, 33 ultra-processing markers were identified and six ultra-processing bullet categories were defined, that is flavour, flavour enhancer, sweetener, colour, other cosmetic additives and non-culinary ingredients. The ingredient lists were analysed concerning these ultra-processing markers and ultra-processing bullet categories, as well as nutrient composition, for all PBMP and MBP. Differences between PBMP and MBP were assessed using chi-square and Mann-Whitney U tests, respectively.

SETTING

Cross-sectional analysis.

PARTICIPANTS

282 PBMP and 149 MBP.

RESULTS

The percentage of ultra-processed food (UPF) items was significantly higher in PBMP (88 %) as compared to MBP (52 %) (P < 0·0001). The proportion of UPF items was numerically higher in 15 out of 18 product categories with differences in six categories reaching statistical significance (P < 0·05). Flavour, flavour enhancer, colour, other cosmetic additives and non-culinary ingredients were significantly more prevalent in PBMP as compared to MBP (P < 0·0001). Concerning nutrient composition, median energy, total fat, saturated fat and protein content were significantly lower, whereas the amounts of carbohydrate, sugar, fibre and salt were significantly higher in PBMP (P < 0·05).

CONCLUSIONS

Ultra-processing markers are significantly more prevalent in PBMP as compared to MBP. Since UPF intake has been convincingly linked to metabolic and CVD, substituting MBP with PBMP might have negative net health effects.

Food literacy and diet quality in young vegans, lacto-ovo vegetarians, pescatarians, flexitarians and omnivores

OBJECTIVE

To investigate whether food literacy competencies and diet quality vary between 16-to-24-year-olds vegans, lacto-ovo vegetarians, pescatarians, flexitarians and omnivores and to assess whether food literacy is associated with diet quality.

DESIGN

Cross-sectional study. Food literacy (general nutrition knowledge, critical nutrition literacy and food skills) and diet quality were measured using an electronic questionnaire.

SETTING

Southern Norway, September 2021 - March 2022.

PARTICIPANTS

Healthy 16-24-year-olds (n 165).

RESULTS

Overall, the mean general nutrition knowledge score was moderate (48·0 out of 67·0); the lowest mean score was found in omnivores and the highest in flexitarians (45·6 v. 51·5) (P = 0·034). The mean score of critical nutrition literacy was also moderate (3·7 out of 5·0); vegans showed higher scores compared to other dietary practices (P = 0·018). No difference was observed in food skills between the different dietary practices. The overall median diet quality score was 46·0 out of 80·0, lowest in omnivores and highest in vegans (42·0 v. 56·0) (P =< 0·001). In multivariate regression analyses, general nutrition knowledge, food skills and vegan dietary practice were significantly associated with higher diet quality.

CONCLUSIONS

We found moderate levels of food literacy across all dietary practices. The food literacy competencies, general nutrition knowledge and food skills were associated with higher diet quality in our sample. Omnivores showed both the lowest general nutrition knowledge level and lowest diet quality scores. In contrast, both flexitarians and vegans scored highest on general nutrition knowledge and diet quality scores, despite being one of the less restrictive and one of the strictest plant-based dietary practices, respectively.

Environmental pressures and pesticide exposure associated with an increase in the share of plant-based foods in the diet

Diets rich in plant-based foods are encouraged for human health and to preserve resources and the environment but the nutritional quality and safety of such diets is debated. This study aimed to model nutritionally adequate diets with increasing plant food content and to characterise the derived diets using a multicriteria approach including, nutrients intake, environmental pressures and exposure to pesticides. Using data of the NutriNet-Santé cohort (N = 29,413), we implemented stepwise optimization models to identified maximum plant-food content under nutritional constraints. Environmental indicators at the production level were derived from the DIALECTE database, and exposure to pesticide residues from plant food consumption was estimated using a contamination database. Plant-based foods contributed to 64.3% (SD = 10.6%) of energy intake in observed diets and may reach up to 95% in modelled diets without jeopardizing nutritional status. Compared to the observed situation, an increase in plant-based foods in the diets led to increases in soy-based products (+ 480%), dried fruits (+ 370%), legumes (+ 317%), whole grains (+ 251%), oils (+ 144%) and vegetables (+ 93%). Animal products decreased progressively until total eviction, except for beef (- 98%). Dietary quality (estimated using the Diet Quality Index Based on the Probability of Adequate Nutrient Intake) was improved (up to 17%) as well as GHGe (up to - 65%), energy demand (up to - 48%), and land occupation (- 56%) for production. Exposures to pesticides from plant-based foods were increased by 100% conventional production and to a much lesser extent by 100% organic production. This study shows that shifting to nutritionally-adequate plant-based diets requires an in-depth rearrangement of food groups' consumption but allows a drastic reduction environmental impact. Increase exposure to pesticide residues and related risks can be mitigated by consuming foods produced with low pesticide input.

Cardiometabolic Effects of Omnivorous vs Vegan Diets in Identical Twins: A Randomized Clinical Trial

Importance

Increasing evidence suggests that, compared with an omnivorous diet, a vegan diet confers potential cardiovascular benefits from improved diet quality (ie, higher consumption of vegetables, legumes, fruits, whole grains, nuts, and seeds).

Objective

To compare the effects of a healthy vegan vs healthy omnivorous diet on cardiometabolic measures during an 8-week intervention.

Design, Setting, and Participants

This single-center, population-based randomized clinical trial of 22 pairs of twins (N = 44) randomized participants to a vegan or omnivorous diet (1 twin per diet). Participant enrollment began March 28, 2022, and continued through May 5, 2022. The date of final follow-up data collection was July 20, 2022. This 8-week, open-label, parallel, dietary randomized clinical trial compared the health impact of a vegan diet vs an omnivorous diet in identical twins. Primary analysis included all available data.

Intervention

Twin pairs were randomized to follow a healthy vegan diet or a healthy omnivorous diet for 8 weeks. Diet-specific meals were provided via a meal delivery service from baseline through week 4, and from weeks 5 to 8 participants prepared their own diet-appropriate meals and snacks.

Main Outcomes and Measures

The primary outcome was difference in low-density lipoprotein cholesterol concentration from baseline to end point (week 8). Secondary outcome measures were changes in cardiometabolic factors (plasma lipids, glucose, and insulin levels and serum trimethylamine N-oxide level), plasma vitamin B12 level, and body weight. Exploratory measures were adherence to study diets, ease or difficulty in following the diets, participant energy levels, and sense of well-being.

Results

A total of 22 pairs (N = 44) of twins (34 [77.3%] female; mean [SD] age, 39.6 [12.7] years; mean [SD] body mass index, 25.9 [4.7]) were enrolled in the study. After 8 weeks, compared with twins randomized to an omnivorous diet, the twins randomized to the vegan diet experienced significant mean (SD) decreases in low-density lipoprotein cholesterol concentration (-13.9 [5.8] mg/dL; 95% CI, -25.3 to -2.4 mg/dL), fasting insulin level (-2.9 [1.3] μIU/mL; 95% CI, -5.3 to -0.4 μIU/mL), and body weight (-1.9 [0.7] kg; 95% CI, -3.3 to -0.6 kg).

Conclusions and Relevance

In this randomized clinical trial of the cardiometabolic effects of omnivorous vs vegan diets in identical twins, the healthy vegan diet led to improved cardiometabolic outcomes compared with a healthy omnivorous diet. Clinicians can consider this dietary approach as a healthy alternative for their patients.

Trial Registration

ClinicalTrials.gov Identifier: NCT05297825.

Vegetarian diets and diets which restrict animal-source foods during childhood in high-income countries

Increasing numbers of populations in the West are restricting their intake of meat and other animal products for reasons relating to health or ethics; in many countries, these restrictions are already common for cultural, religious, or socio-economic reasons. By following their parent's diet, children are exposed in parallel. This narrative review aims at assessing current data regarding vegetarian diets in children from birth to 18 years of age, which include, by increasing degree of restriction, flexitarian, lacto-ovo-vegetarian, lacto-vegetarian, pescatarian, vegan and macrobiotic diets. The 202 references include 45 studies in children. The more restrictive the diet and the younger the child, the greater the risk of nutritional deficiency. Of particular concern are vitamin B12, iron, zinc, calcium, n-3 long-chain polyunsaturated fatty acids, and protein and energy intake, especially in pregnant and nursing women, infants and young children. Providing an adequate lacto-ovo-vegetarian diet is relatively easy, whereas the maintenance of more restrictive diets may be challenging. The benefits and risks of vegetarian diets in adults are relatively well documented, but data for children are scarce. Vegan and macrobiotic diets should be discouraged in pregnant and lactating mothers as well as in young children, who, otherwise, should pay careful attention to ensuring nutritional adequacy, blood testing and appropriate supplementation. The health consequences of a chosen diet should be discussed with parents and adolescents to ensure the best possible adherence to advice and prescriptions. There is a need for well conducted studies in children but also for better knowledge of nutrition in healthcare professionals.Abbreviations: ALA: α-linolenic acid; ARA: arachidonic acid; ASF: animal source foods; BMC: bone mineral content; BMD: bone mineral density; DHA: docosahexaenoic acid; DRV: dietary reference value; EPA: eicosapentaenoic acid; FLD: flexitarian diet; LA: linoleic acid; LC-PUFA: long-chain polyunsaturated fatty acids; LOVD: lacto-ovo-vegetarian diet; LVD: lacto-vegetarian diet; MAD: macrobiotic diet; OMD: omnivorous diet; PSF: plant-source foods; SFA: saturated fatty acids; VGD: vegetarian diets; VND: vegan diet.

Plant-Based Dietary Indices in Relation to Nutrient and Food Group Intakes in Preschool-Aged Children

Dietary guidance promotes plant-based foods, yet minimal research has examined intake in children. This study examined plant-based food intake in preschool-aged children using plant-based dietary index (PDI) metrics and related these metrics to nutrient and food group intakes. Dietary data were collected from preschool-aged children (n = 283, 3.45 ± 1.22 years) from the Guelph Family Health Study at baseline using the Automated Self-Administered 24-Hour Dietary Assessment Tool. Food intake servings were assigned to 16 food groups for calculation of overall PDI (oPDI), healthful PDI (hPDI), and less healthful (lhPDI) scores and summarized into tertiles for energy-adjusted comparisons. For oPDI, participants in the highest vs. lowest tertile had higher intakes of nutrients and food groups to encourage (e.g., dietary fiber, fruits) as well as lower intakes of nutrients to encourage (e.g., calcium, vitamin D). For hPDI, participants in the highest vs. lowest tertile had higher intakes of nutrients and food groups to encourage and lower intakes of those to limit (e.g., saturated fat, sweets and desserts). For lhPDI, participants in the highest vs. lowest tertile had higher intakes of nutrients and food groups to limit and lower intakes of those to encourage. These results can inform dietetic practice for dietary guidance that promotes plant-based foods in children.

A Dietary Model of Partial Meat Replacement with Walnuts Demonstrates Changes in the Nutrient Profile and Quality of the United States Population's Diet

The purpose of the study is to assess the impact of partial meat replacement with walnuts using a dose-escalation approach on nutrient intake and diet quality in the usual US diet. Food modeling was implemented using the nationally representative 2015-2018 National Health and Examination Survey (NHANES), with a focus on non-nut consumers, which included 2707 children and adolescents and 5190 adults. Walnuts replaced meat in a dose-escalating manner (0.5, 1, 1.5, and 2 oz walnuts per day replaced 1, 2, 3, and 4 oz meat, respectively). Diet quality was estimated using the population ratio method of the 2015 Healthy Eating Index. The usual intake of nutrients was estimated using the National Cancer Institute method. Significant differences were determined using non-overlapping 95% confidence intervals. The partial replacement of meat with walnuts demonstrated significant increases in the mean intake of fiber, magnesium, and omega-3 fatty acids and significant decreases in cholesterol and vitamin B12 in the modeled diets for children, adolescents, and adults. Additionally, the partial replacement of meat with walnuts improved overall diet quality. Walnut consumption at 1-2 oz as a replacement for some meat may improve nutrient intake and diet quality across age groups.

Self-reported engagement in healthy eating behaviors is associated with favorable dietary intake among adults in Puerto Rico

A diet high in quality is essential for prevention of chronic diseases. Specific healthy eating behaviors may modulate dietary intake. However, these behaviors have been seldomly studied, particularly in Puerto Rico (PR), a population with documented poor dietary quality and high burden of chronic diseases. This study aimed to document self-reported engagement in eating behaviors and examine their associations with intake of nutrients and diet quality. We hypothesized that greater engagement in healthy eating behavior would be associated with greater diet quality. This cross-sectional analysis used data from the PRADLAD study (adults aged 30-75 years residing in the San Juan, PR, area [n = 234]). Frequency (never, sometimes, often, always) of habitual eating behaviors was measured. Dietary intake was assessed with a food frequency questionnaire. Diet quality was measured with the Alternate Healthy Eating Index-2010. Statistical analyses included adjusted linear models. The most common behavior was "controlling intake of salt" (51.7%). Engaging "always" (vs. less frequently) in making healthier meals, reading nutrition facts labels, searching media for healthy eating information, counting calories, buying organic foods, eating a vegetarian diet, and controlling intake of salt, fat, carbohydrates/sugar, and portions were associated with higher Alternate Healthy Eating Index-2010 scores (P < .05). Controlling intakes of fats, carbohydrates/sugars, and portions "always" was associated with lower intakes of trans fats, added sugars, and total food (g), respectively (P < .05). Engagement in eating a vegetarian diet "always" was associated with higher intake of plant-based protein (P < .05). In conclusion, adults following several habitual eating behaviors had greater diet quality and a lower amount of unfavorable nutrients. Encouraging adherence to these behaviors may contribute to healthier dietary intake.

Effect of a pescetarian and vegan diet on fatty acid composition in blood and spermatozoa in young healthy men

INTRODUCTION

There is a growing interest in vegetarian and vegan diets, but both can potentially affect tissue fatty acids (FA) composition. We aimed to evaluate the effect of vegetarian diets on plasma, erythrocytes, and sperm n-3 polyunsaturated fatty acids (n-3 PUFA) status in healthy young men.

METHODS

Four groups were studied: i) men consuming a regular omnivore diet (OMV-1, n = 35); ii) men consuming an omnivore diet but excluding fish and seafood (OMV-2, n = 34); iii) men consuming a pescetarian diet (including dairy, eggs, fish, and seafood) (PESC, n = 36); and iv) men following a strict vegan diet (VEG, n = 35). Participants in each group should follow their diet for at least the previous 12 months. Diet evaluation used a structured validated food frequency questionnaire. FA composition was measured in plasma, erythrocyte phospho-lipids, and spermatozoa by gas-liquid chromatography, expressed as a mole percentage of the total FA content.

RESULTS

Main findings showed higher alpha-linolenic fatty acid (ALA) and total n-3 PUFA dietary intake in the VEG group. In plasma, arachidonic and eicosapentaenoic acids were higher in OMV and PESC groups, whereas docosahexaenoic acid (DHA) level was lower in VEG. Higher ALA, but reduced DHA and total n-3 PUFA levels were found in erythrocytes and spermatozoa in the VEG group.

CONCLUSION

Higher dietary ALA intake was found in pescetarians and vegan men. However, the higher ALA intake was not reflected in higher DHA content in the evaluated tissues. PUFA assessment, with particular emphasis in DHA, are necessary to improve PUFA status in vegan men.

Greater adherence to the Dietary Guidelines for Americans is associated with lower diet-related greenhouse gas emissions but higher costs

Introduction

Few studies have evaluated the sustainability of popular diet patterns in the US, which limits policy action and impedes consumer efficacy to make sustainable dietary changes. This study filled this gap by evaluating the relationship between diet quality, greenhouse gas emissions (GHGE), and diet cost for plant-based, restricted carbohydrate, low grain, low fat, and time restricted diet patterns.

Methods

Dietary data were retrieved from the National Health and Nutrition Examination Survey (2011-2018, n = 8,146) and linked with data on GHGE and food prices from publicly available databases. Diet quality was measured using the Healthy Eating Index-2015. The present study (1) compared the mean diet quality, GHGE, and diet cost between diet patterns, (2) evaluated the association of diet quality to GHGE and diet cost for each diet pattern, and (3) estimated the contribution of food sources to GHGE and diet cost for each diet pattern.

Results

Higher diet quality was associated with lower GHGE for the general population and for most diet patterns (p < 0.01) except for the plant-based and time restricted diet patterns (p > 0.05). Higher diet quality was associated with higher cost for the general population and for all dietary patterns (p < 0.01) except the time restricted diet pattern (p > 0.05). Protein foods, mostly beef, accounted for the largest share of GHGE (29-40%) and diet cost (28-47%) for all diet patterns except plant-based.

Discussion

Higher diet quality was associated with lower GHGE but was often accompanied by higher diet cost. These sustainability trade-offs can help inform major policy discussions in the US and shed light on further research needs in the area of food systems transformation.

Comparison of the Health Status of Vegetarians and Omnivores Based on Biochemical Blood Tests, Body Composition Analysis and Quality of Nutrition

Many vegetarians are motivated by the health aspect of starting a plant-based diet. This diet can offer many health benefits. The study aimed to check whether people on a vegetarian diet are in good health, have a good nutritional intake, and follow the principles of healthy eating compared with omnivores. Twenty-two vegetarians on a vegetarian diet for more than five years and 22 omnivores aged 18-45 were interviewed. Each of them was given a food questionnaire, body composition analysis (BIA), and biochemical blood analysis, and their 7-day diet was analyzed. Polish vegetarians exhibit similar health statuses and tend towards better health than omnivores. They have an adequate body composition. Biochemical blood analysis showed no significant differences in blood parameters between vegetarians and omnivores, despite specific deficiencies such as vitamin B₁₂, vitamin D and elevated homocysteine levels in vegetarians. They have a better nutritional status and follow good dietary principles. However, they were more likely to consume alcohol, add salt to their meals and sweeten hot drinks. In addition, the lifestyle of vegetarians can be described as healthier, as they are more likely to engage in leisure-time physical activity and get enough sleep.

Vegetarian diets in Spain: Temporal evolution through national health surveys and their association with healthy lifestyles

OBJECTIVE

To assess the prevalent consumption trend between 2001 and 2017 and the healthy lifestyles associated with consuming a plant-based diet in the Spanish population.

METHODOLOGY

A representative Spanish sample was analysed (>15 years old) from the Spanish National Health Survey for years 2001 (n=8568), 2006 (n=25,649), 2011 (n=19,027) and 2017 (n=21,986). The population was classified as omnivore, vegetarian, or vegan. The lifestyle variables were physical activity, tobacco and alcohol consumption, and body mass index (BMI). The χ2 test was used to evaluate diet change between 2001 and 2017. T-Student and χ2 were used to compare lifestyles of omnivores and vegetarians/vegans. Logistic regression was used to analyse lifestyles associated with plant-based diets.

RESULTS

0.2% of the Spanish population followed a plant-based diet. Between plant-based diet consumers there was an increase in vegans vs. vegetarians between 2001 (9.5% vs. 90.5%) and 2017 (65.3% vs. 34.7%) (p=0.007). Compared to 2001, following a plant-based diet was more likely in 2006 (OR=2.08, p=0.004), 2011 (OR=1.89, p=0.02) and 2017 (OR=1.75, p=0.04). Those who consume alcohol (OR=0.65, p=0.008), who were overweight (OR=0.48, p<0.001) or who were obese (OR=0.40, p=0.001) were less likely to consume a plant-based diet.

CONCLUSIONS

Despite an increase in the consumption of plant-based diets between 2001 and 2017, there was a low prevalence of consumption in all years studied. There was a greater probability of consuming plant-based diets among the Spanish population with healthy behaviours. These findings could help design strategies focused on healthy nutritional behaviours.

Assessing the Quality of Simulated Food Patterns with Reduced Animal Protein Using Meal Data from NHANES 2017-2018

The nutritional consequences of progressively replacing meat products with plant-based foods need to be systematically evaluated. Modeling analyses provide insights into the predicted food consumption and nutritional adequacy of plant-based diets. We developed a novel methodology to simulate food patterns and evaluate diet quality. Meal data from the National Health and Nutrition Examination Survey (NHANES) 2017-2018 was used to create 100 7-day meal plans subject to various nutrient and food group optimization criteria. Omnivore (reference diet), flexitarian, pescatarian, and vegetarian food patterns were modeled using mixed integer linear programming. The modeled food patterns used the 25th and 75th percentiles of the US Usual Dietary Intakes to set the optimization constraints. The diet quality was determined using the Healthy Eating Index 2015 (HEI-2015). The modeled vegetarian, pescatarian, and flexitarian food patterns outperformed the omnivore diet on the HEI-2015, with the vegetarian pattern achieving the highest score (82 for females, 78 for males). Modeled flexitarian patterns, with a 25 to 75% reduction in animal protein, offer viable options for those seeking to reduce but not eliminate their animal protein intake while supporting the transition from omnivore to fully plant-based diets. This methodology could be applied to evaluate the nutrient and diet quality of different dietary patterns with various constraints.

Greenhouse gas emissions, cost, and diet quality of specific diet patterns in the United States

BACKGROUND

Major policy agendas are calling for accelerated investment in research that addresses the impact of diet patterns on multiple domains of sustainability.

OBJECTIVE

To evaluate the comparative greenhouse gas emissions, diet cost, and diet quality of plant-based, low grain, restricted carbohydrate, low fat, and time restricted diet patterns on a daily per capita basis.

DESIGN

Dietary data from the National Health and Nutrition Examination Survey (2013-2016, n=4,025) were merged with data on greenhouse gas emissions (GHGE) and food prices from multiple databases. The Healthy Eating Index-2015 was used to measure diet quality.

RESULTS

The plant-based diet pattern had the lowest GHGE (3.5 kg CO2eq, 95% CI: 3.3, 3.8 kg CO2eq) and among the lowest diet cost ($11.51, 95% CI: $10.67, $12.41), but diet quality (45.8, 95% CI: 43.3, 48.5) was similar (P>0.005) to most other diet patterns. All of the sustainability impacts of the low grain diet pattern were intermediate. The restricted carbohydrate diet pattern had the highest diet cost ($18.46, 95% CI: $17.80, $19.13) but intermediate diet quality (46.8, 95% CI: 45.7, 47.9) and moderate-to-high GHGE (5.7 kg CO2eq, 95% CI: 5.4, 5.9 kg CO2eq). The low fat diet pattern had the highest diet quality (52.0, 95% CI: 50.8, 53.1) and intermediate GHGE (4.4 kg CO2eq, 95% CI: 4.1, 4.6 kg CO2eq) and diet cost ($14.53, 95% CI: $13.73, $15.38). The time restricted diet pattern had among the lowest diet quality score (42.6, 95% CI: 40.8, 44.6), had GHGE similar to most other diet patterns (4.6 kg CO2eq, 95% CI: 4.2, 5.0 kg CO2eq), and low-to-moderate diet cost ($12.34, 95% CI: $11.38, $13.40).

CONCLUSIONS

Most diet patterns were associated with sustainability trade-offs. The nature of those trade-offs can help inform discussions on food and nutrition policy in the US, including the National Strategy on Hunger, Nutrition, and Health, and future Dietary Guidelines for Americans.

Plant-based and vegetarian diets: an overview and definition of these dietary patterns

PURPOSE

This paper aims to present an overview of the definitions of "plant-based and "vegetarian diets" adopted by different organizations worldwide, proposing new standard definitions and discussing the notion of vegetarianism as a restrictive dietary pattern.

METHODS

An extensive literature review on the different definitions of vegetarian and plant-based diets was conducted. Definitions of different international vegetarian and vegan organizations were also taken into account. Objective definitions for vegetarian and plant-based diets, as well as for their subcategories, were proposed. Other aspects related to how vegetarian diets are viewed and defined were also discussed.

RESULTS

We proposed that a vegetarian diet should be defined as "a dietary pattern that excludes meat, meat-derived foods, and, to different extents, other animal products". This definition would include, among others, ovolactovegetarian and vegan diets. The proposed definition for a plant-based diet was "a dietary pattern in which foods of animal origin are totally or mostly excluded". Other types of diets, such as flexitarian and pescetarian diets, could be considered plant-based. A vegetarian diet should not be considered restrictive. Instead, terms such as alternative or non-conventional could be used to define it and to distinguish it from the conventional diet adopted by most of the Western population.

CONCLUSION

This paper was able to elaborate objective definitions of vegetarian and plant-based diets. Standardizing nomenclatures may reduce misinterpretation and confusion in this field of study.

Eating Patterns of Young Women (18–25 y) with Overweight and Obesity: A Preliminary Investigation

Overweight and obesity impact up to 40% of young women in Australia; however, young women are challenging to recruit to research and are rarely the focus of weight loss interventions. This study aimed to examine dietary patterns in young women (18–25 years; BMI > 25 kg/m2). An analysis of participants’ (mean age: 22.6 year; BMI: 32.2 kg/m2) 3-day food records found young women with overweight/obesity consumed a diet characterised by total energy intake of 9174 (2526) kJ/day, with the first meal at 9:12 am (range: 4:30 am–12:40 pm), the last at 10:43 pm (range: 2:40 pm–2:00 am), and an average eating window of 11.5 h. Young women had poor quality diets, which did not meet dietary recommendations for most core food groups, and high intake of refined carbohydrates. They also reported consuming at least one takeaway meal per day and >30% of total energy intake was from discretionary items. The findings showed that young women with overweight or obesity consume most of their energy intake in the afternoons and late into the evenings and have poor-quality diets with high-discretionary intake, each of which have been shown in previous work to be associated with increased weight and risk of metabolic comorbidities. While these findings require further examination in larger groups with both qualitative and longitudinal data collection to verify the impact of these eating patterns on weight maintenance, the eating behaviours identified here may present a suitable target for novel weight loss interventions in young women, who are an understudied population group in need of tailored weight management solutions.

Dietary Intake and Circulating Amino Acid Concentrations in Relation with Bone Metabolism Markers in Children Following Vegetarian and Omnivorous Diets

Scientific studies reported that most vegetarians meet the total protein requirements; however, little is known about their amino acid intakes. We aimed to assess dietary intake and serum amino acid levels in relation to bone metabolism markers in prepubertal children on vegetarian and traditional diets. Data from 51 vegetarian and 25 omnivorous children aged 4–9 years were analyzed. Dietary intake of macro- and micronutrients were assessed using the nutritional program Dieta 5®. Serum amino acid analysis was performed using high-pressure liquid chromatography technique, 25-hydroxyvitamin D and parathormone–electrochemiluminescent immunoassay, and bone metabolism markers, albumin, and prealbumin levels using enzyme-linked immunosorbent assay. Vegetarian children had a significantly lower intake of protein and amino acids with median differences of about 30–50% compared to omnivores. Concentrations of four amino acids (valine, lysine, leucine, isoleucine) in serum varied significantly by diet groups and were lower by 10–15% in vegetarians than meat-eaters. Vegetarian children also had lower (p < 0.001) serum albumin levels compared to omnivores. Among bone markers, they had higher (p < 0.05) levels of C-terminal telopeptide of collagen type I (CTX-I) than omnivores. Correlation patterns between amino acids and bone metabolism markers differed in the vegetarian and omnivore groups. Out of bone markers, especially osteoprotegerin was positively correlated with several amino acids, such as tryptophan, alanine, aspartate, glutamine, and serine, and ornithine in vegetarians. Vegetarian children consumed apparently sufficient but lower protein and amino acids compared to omnivores. In circulation these differences were less marked than in the diet. Significantly lower amino acid intake and serum levels of valine, lysine, leucine, and isoleucine as well as the observed correlations between serum amino acids and biochemical bone marker levels indicated the relations between diet, protein quality, and bone metabolism.

Association of plant-based dietary patterns in first trimester of pregnancy with gestational weight gain: results from a prospective birth cohort

BACKGROUND/OBJECTIVES

Plant-based dietary patterns are becoming more popular worldwide. We aimed to examine the relationship between plant-based dietary patterns and the risk of inadequate or excessive gestational weight gain (GWG) in Iranian pregnant women.

METHODS

We prospectively followed 657 pregnant women in Iran. Adherence to the plant-based diet, represented by plant-based (PDI), healthy (hPDI) and unhealthy plant-based (uPDI) dietary indexes was evaluated by applying a 90-item food frequency questionnaire during the first trimester of pregnancy. Multivariable-adjusted Cox proportional-hazards regression model was used to compute hazard ratios (HRs) and 95% confidence intervals (CIs) across quartiles of plant-based diet scores.

RESULTS

Over 25,562 person-weeks of follow-up, we documented 106 and 294 participants with inadequate and excessive GWG, respectively. We found a strong inverse association between adherence to the PDI and inadequate GWG after adjustment for demographic and confounding variables. Women in the highest quartile of the PDI had 50% lower risk of inadequate GWG than those in the lowest quartile (adjusted HR: 0.50; 95%CI 0.29, 0.89; P = 0.02). No significant association was found between hPDI and uPDI and inadequate GWG. There was no association between PDI, hPDI, and uPDI and the risk of excessive GWG.

CONCLUSIONS

Greater adherence to a plant-based diet during the first trimester of pregnancy may be associated with a lower risk of inadequate GWG. This finding needs to be confirmed in larger cohort studies, considering other pregnancy outcomes such as birth weight and the potential changes across the trimester in terms of food types and quantity.

Breakfast Consumption and Diet Quality of Teens in Southwestern Ontario

Background

Breakfast skipping has previously been associated with worse diet quality among adolescents; the latter increases the risk of chronic disease. However, many studies do not consider diet quality as a function of calories, which is problematic as skippers tend to consume less energy than consumers. Additionally, due to the lack of one accepted definition of both breakfast skipping and diet quality, it is unclear how differences found may change when using varying definitions.

Objectives

We aimed to compare the Healthy Eating Index-2015 (HEI-2015) scores and nutrient intakes of teen breakfast skippers and consumers in Southwestern Ontario, Canada.

Methods

Cross-sectional, baseline data were used from SmartAPPetite, an ongoing nutrition intervention study. Singular 24-h dietary recalls and sociodemographic data from 512 adolescents aged 13-19 y were used to compare HEI-2015 scores and nutrient intakes via multivariable linear regression.

Results

Previous day breakfast skippers had significantly lower HEI-2015 scores (-4.4; 95% CI: -8.4, -0.4) and significantly lower intakes of calories, saturated fat, and vitamin C, as well as significantly higher intake of sodium and total fat.

Conclusions

Previous day breakfast consumers had significantly higher diet quality scores and better nutrient intakes than breakfast skippers, although, on average, both had poor diet quality. Consequently, it is unlikely that simply advising teens to consume breakfast will result in meaningful change in diet quality, and more effort should be placed on promoting nutritious breakfasts.

Effect of Animal Protein Intake on Meeting Recommendations for Nutrient Intake among US Adults, What We Eat in America, NHANES 2015-2018

Background

Replacing some animal sources of protein with plant foods is encouraged. Nutrient intake may reflect changes in the protein source. The adequacy of habitual nutrient intake among US adults has not been evaluated by the level of animal protein (AP) intake.

Objectives

The objective of this study was to compare food consumption and nutrient intake and adequacy among quintiles of percent AP intake.

Methods

Dietary intake data of adults 19+ y (N = 9706) from What We Eat in America, National Health and Nutrition Examination Survey 2015-2018 were used. Proportions of protein from animal and plant sources were estimated from ingredients in the Food and Nutrient Database for Dietary Studies 2015-2018, and then applied to dietary intakes. Intakes were classified by Q of percent AP. Food intake was described using the United States Department of Agriculture Food Patterns components. Usual nutrient intakes were estimated using the National Cancer Institute Method and compared with age and gender-specific Dietary Reference Intakes (DRIs). Comparisons between quintiles were made using t-tests. Results were considered significant at P < 0.01.

Results

Total protein intake was higher as the Q of AP intake increased. Among the higher quintiles of percent AP, <1% did not meet their DRIs for protein than 17% in Q1 and 5% in Q2 (P < 0.01). In quintiles with lower compared with higher percent AP, there were significantly higher percentages not meeting DRIs for vitamins A, B12, choline, zinc, and calcium but meeting recommendations for folate, vitamin C, saturated fat, cholesterol, and fiber (P < 0.01). Among all quintiles, over one-third did not meet DRIs for fiber, vitamins A, C, D, E, K, choline, calcium, and potassium.

Conclusions

Replacing protein from animal sources with plant foods may result in lower intakes of protein and some nutrients but a better intake of dietary components associated with reducing chronic disease risk. The current intake of US adults indicates dietary improvements are needed, regardless of protein source.

Dietary Antioxidants, Quality of Nutrition and Cardiovascular Characteristics among Omnivores, Flexitarians and Vegetarians in Poland-The Results of Multicenter National Representative Survey WOBASZ

Several reports have shown that more plant-based dietary patterns provide a higher intake of antioxidants compared to diets rich in meat and animal products. Data on the intake of key nutrients in cardiovascular disease (CVD) prevention in relation to particular diets in countries of Central and Eastern Europe are scarce. The aim of this study was to assess quality of nutrition and CVD characteristics in a representative sample of Polish adults following different dietary patterns. Special regard was paid to the intake of natural antioxidants. The study comprised 13,318 (7159 females) randomly selected adults aged ≥ 20 years participating in the National Multicentre Health Surveys WOBASZ and WOBASZ II. The subjects were categorized into groups of omnivores (92.4%), flexitarians (7.4%) and vegetarians (0.16%) according to type of diet using the Food Frequency Questionnaire and 24 h dietary recall. The obtained results showed that neither flexitarians nor vegetarians represented better dietary habits or lifestyle behaviors compared to omnivores. Flexitarians had significantly lower daily energy intake than omnivores, but their diet was rich in total fat (above 30% of daily energy consumption) and low in fiber. Omnivores declared a higher consumption of fresh vegetables (p < 0.001), fresh fruit (p < 0.01), coffee (p < 0.01) and tea (p < 0.05, in women only) than flexitarians. Omnivores had significantly higher intake of natural antioxidants (vitamin C, E, zinc in both genders and vitamin A in men) as compared with flexitarians. Among women, the highest adherence to the intake of recommended amounts of antioxidant nutrients was noted among omnivores. Among men, vegetarians had the highest proportion of meeting the guidelines for vitamin A (77.8%), E (66.7%) and C (66.7%), while the lowest proportions were found in flexitarians (69.9%, 39.5% and 32.4%, respectively). The groups did not differ in terms of smoking and physical activity level. There were no significant differences in the analyzed CVD characteristics between omnivores and flexitarians. In women, vegetarians had substantially lower BMI than omnivores (p < 0.05) and flexitarians (p < 0.05) and a lower mean serum glucose compared with omnivores (p < 0.01) and flexitarians (p < 0.05). Vegetarians had lower prevalence of hypertension and obesity than meat eaters. In conclusion, the results of the current research showed an inappropriate intake of several nutrients, including highly potent antioxidants, irrespective of the dietary regimen. Flexitarians did not have a more favorable CVD profile than omnivores. Taking into account the growing popularity of diets with reduced animal products, there is a need to elaborate strategies providing Polish adults with guidance regarding properly balanced nutrition.

Measuring Adherence to Sustainable Healthy Diets: A Scoping Review of Dietary Metrics

Comprehensive metrics that provide a measure of dietary patterns at global and national levels are needed to inform and assess the effectiveness of policy actions that promote sustainable healthy diets. In 2019, the Food and Agriculture Organization of the United Nations and the World Health Organization reported 16 guiding principles of sustainable healthy diets, but it is still unknown how these principles are considered in dietary metrics. This scoping review aimed to explore how principles of sustainable healthy diets are considered in dietary metrics used worldwide. Forty-eight food-based, investigator-defined dietary pattern metrics assessing diet quality in free-living, healthy populations at the individual or household level were assessed against the 16 guiding principles of sustainable healthy diets, which was used as a theoretical framework. A strong adherence of the metrics to health-related guiding principles was found. Metrics had a weak adherence to principles related to environmental and sociocultural aspects of diets, except for the principle related to diets being culturally appropriate. No existing dietary metric captures all principles of sustainable healthy diets. Notably, the significance food processing, environmental, and sociocultural aspects of diets are generally understated. This likely reflects the lack of focus on these aspects in current dietary guidelines, which highlights the importance of including these emerging topics in future dietary recommendations. The absence of quantitative metrics that comprehensively measure sustainable healthy diets limits the body of evidence that would otherwise inform national and international guideline developments. Our findings can help grow the quantity and quality of the body of evidence available to inform policy activities to realize 2030 Sustainable Development Goals of multiple United Nations. Adv Nutr 2022;x:xx.

Association between meatless diet and depressive episodes: A cross-sectional analysis of baseline data from the longitudinal study of adult health (ELSA-Brasil)

BACKGROUND

The association between vegetarianism and depression is still unclear. We aimed to investigate the association between a meatless diet and the presence of depressive episodes among adults.

METHODS

A cross-sectional analysis was performed with baseline data from the ELSA-Brasil cohort, which included 14,216 Brazilians aged 35 to 74 years. A meatless diet was defined from in a validated food frequency questionnaire. The Clinical Interview Schedule-Revised (CIS-R) instrument was used to assess depressive episodes. The association between meatless diet and presence of depressive episodes was expressed as a prevalence ratio (PR), determined by Poisson regression adjusted for potentially confounding and/or mediating variables: sociodemographic parameters, smoking, alcohol intake, physical activity, several clinical variables, self-assessed health status, body mass index, micronutrient intake, protein, food processing level, daily energy intake, and changes in diet in the preceding 6 months.

RESULTS

We found a positive association between the prevalence of depressive episodes and a meatless diet. Meat non-consumers experienced approximately twice the frequency of depressive episodes of meat consumers, PRs ranging from 2.05 (95%CI 1.00-4.18) in the crude model to 2.37 (95%CI 1.24-4.51) in the fully adjusted model.

LIMITATIONS

The cross-sectional design precluded the investigation of causal relationships.

CONCLUSIONS

Depressive episodes are more prevalent in individuals who do not eat meat, independently of socioeconomic and lifestyle factors. Nutrient deficiencies do not explain this association. The nature of the association remains unclear, and longitudinal data are needed to clarify causal relationship.

Nutritionally adequate and environmentally respectful diets are possible for different diet groups: an optimized study from the NutriNet-Santé cohort

BACKGROUND

Research has shown that vegetarian diets have a low environmental impact, but few studies have examined the environmental impacts and nutritional adequacy of these diets together, even though vegetarian diets can lead to nutritional issues.

OBJECTIVES

Our objective was to optimize and compare 6 types of diets with varying degrees of plant foods (lacto-, ovolacto-, and pescovegetarian diets and diets with low, medium, and high meat content) under nutritional constraints.

METHODS

Consumption data in 30,000 participants were derived from the French NutriNet-Santé cohort using an FFQ. Diets were optimized by a nonlinear algorithm minimizing the diet deviation while meeting multiple constraints at both the individual and population levels: nonincrease of the cost and environmental impacts (as partial ReCiPe accounting for greenhouse gas emissions, cumulative energy demand, and land occupation, distinguishing production methods: organic and conventional), under epidemiologic, nutritional (based on nutrient reference values), and acceptability (according to the diet type) constraints.

RESULTS

Optimized diets were successfully identified for each diet type, except that it was impossible to meet the EPA (20:5n-3) + DHA (22:6n-3) requirements in lacto- and ovolactovegetarians. In all cases, meat consumption was redistributed or reduced and the consumption of legumes (including soy-based products), whole grains, and vegetables were increased, whereas some food groups, such as potatoes, fruit juices, and alcoholic beverages, were entirely removed from the diets. The lower environmental impacts (as well as individual indicators) observed for vegetarians could be attained even when nutritional references were reached except for long-chain n-3 (omega-3) fatty acids.

CONCLUSIONS

A low-meat diet could be considered as a target for the general population in the context of sustainable transitions, although all diets tested can be overall nutritionally adequate (except for n-3 fatty acids) when planned appropriately.This trial was registered at clinicaltrials.gov as NCT03335644.

Consumption of Key Food Groups by Individuals Consuming Popular Diet Patterns: Mixed Effects of Replacing Foods High in Added Sugar, Sodium, Saturated Fat, and Refined Grains

Adults in the United States are increasingly following 'popular' diet patterns that restrict food groups, macronutrients, or eating time. However, the intake of food groups associated with these diet patterns has not been well characterized. The objectives of this study were to (1) characterize the mean intake of food groups among consumers of popular diet patterns in the US, and (2) model the effect of targeted food substitutions on the intake of food groups. Data were acquired from the National Health and Nutrition Examination Survey, 2005-2018 (n = 34,411). A diet model was developed to assess the effects of replacing one serving each of foods highest in added sugar, sodium, saturated fat, and refined grains with healthy alternatives on the intake of key food groups for each diet pattern. Modeled replacement resulted in increased intake of fruit and whole grains and decreased intake of dairy for most diet patterns, while the effects on the intake of vegetables, protein foods, and oils were variable across diet patterns. The complexity of the natural eating environment, in which many people consume mixed dishes that include both healthy and less healthy ingredients, produces a challenge for health professionals when providing dietary counseling. Nevertheless, this substitution approach may help improve adherence to dietary guidelines, especially if used as a steppingstone for further dietary improvement.

Do urban tourists prefer vegetarianism? An urban-rural comparison of vegetarian consumption in China

The adoption of a vegetarian diet might have public health and environmental benefits. However, little is known about urban and rural Generation Z tourists' attitudes toward vegetarianism or vegetarian consumption within the Chinese urban and rural settings. Hence, to address this gap, the present study adopted a sequential and mixed research approach based on a survey (n = 212) and laddering interviews (n = 20) to validate post-millennial tourists' motives for adopting a vegetarian diet. The results identified the top four motives as environmental protection and resource conservation, ethical consideration, personal taste and choice, and personal healthcare issues. The top four barriers to vegetarianism were unavailability and limited choice, peer pressure, traditional prejudice/habit, and the inability to change. The results also demonstrated that both rural and urban tourists adopt vegetarianism mainly for environmental protection and ethical consideration, a subtle difference between them is that urban vegetarians emphasized ethical considerations more but rural ones emphasized food and variety. Urban consumers considered unavailability and limited choice as the topmost barriers to being vegetarian, while rural vegetarians found traditional prejudice to be restricting. Due to traditional dietary habits and peer influence, rural tourists face many more challenges when adopting a vegetarian diet. Understanding the perceived benefits and barriers to being vegetarian in different regions will not only enrich the theory of food nutrition but also expand Generation Z tourists' consumption behavior and practices.

Examining dietary behaviours, diet quality, motives and supplementation use in physically active individuals following vegetarian-based eating patterns

The adoption of vegetarian-based dietary patterns among athletes has been gaining popularity. However, limited research examines the dietary behaviours within this group. Therefore, the aim of this study was to examine self-reported dietary behaviours in a cohort of physically active individuals following vegetarian-based dietary patterns, recruited via social media. A 52-item online survey was created with questions related to demographics, physical activity, eating patterns and supplementation use. An external link to the Australian Automated Self-Administered 24-h (ASA24-AU) recall was included to examine nutrient intakes. Dietary quality was assessed using the Alternate Healthy Eating Index-2010 (AHEI-2010) and the Dietary Phytochemical Index (DPI) tools. A total of 781 (84.8%) respondents completed the survey in 2018. Principal motives for adhering to a vegetarian-based dietary pattern included animal rights (86.5%), environmental concerns (75.4%), health reasons (69.6%) and improving physical performance (24.1%). Vitamin B12 was the most commonly reported supplement (58.1%) followed by protein powder (36.3%) and vitamin D (35.9%). A total of 133 respondents completed the ASA24-AU dietary recall with generally adequate nutrient intakes and a high-quality diet as assessed by the AHEI-2010 and DPI. A significant minority of physically active individuals following vegetarian-based diets do so with the aspiration of improving their exercise performance. Dietary quality was considered high in this group for recreational physical activity, although intakes of vitamin B12 and LC n-3 PUFA were low.

Association between the quality of plant-based diets and risk of frailty

BACKGROUND

The Mediterranean diet and other dietary patterns rich in fruits and vegetables have been linked to lower risk of frailty in older adults. However, not all plant-based diets are necessarily healthful, and no previous study has evaluated the role of the quality of plant-based dietary patterns in frailty risk. Our aim was to assess the association between plant-based diet quality and risk of frailty.

METHODS

Prospective cohort consisted with 82 234 women aged ≥60 years from the Nurses' Health Study, who were followed from 1990 through 2014. The dates of analysis were April 14 to June 23, 2021. Dietary data were collected every 4 years using a validated semi-quantitative food frequency questionnaire. The plant-based diet quality was assessed with two indices (range 18-90 points): (a) healthful plant-based diet index (hPDI), where healthy plant foods (whole grains, fruits, vegetables, nuts, legumes, vegetable oils and tea/coffee) received positive scores, while less healthy plant foods (fruit juices, sweetened beverages, refined grains, potatoes, and sweets/desserts) and animal foods received reverse scores; and (b) unhealthful plant-based diet index (uPDI) where positive scores were given to less healthy plant foods and reverse scores to healthy plant foods and animal foods. Frailty incidence was assessed every 4 years, being defined as having three or more of the following five criteria from the FRAIL scale: fatigue, low strength, reduced aerobic capacity, having ≥5 illnesses and weight loss ≥5%. Multivariable-adjusted Cox proportional-hazards models were used to estimate hazard ratios (HRs) and their 95% confidence interval (CI).

RESULTS

We identified 12 910 incident cases of frailty over 1 176 401 person-year follow-up. In the multivariable analysis, the hPDI was inversely associated with the risk of frailty (hazard ratio [HR] for the highest vs. lowest quintile: 0.77, 95% confidence interval: 0.72-0.81; P trend <0.001). In addition, a 10-unit increment in the hPDI was associated with a relative 15% lower risk of frailty. Conversely, a direct association was found between the uPDI and risk of frailty (HR highest vs. lowest quintile: 1.24 [1.17, 1.32], P trend <0.001). These associations were consistent for each frailty criterion, among participants with no frailty criteria at baseline, after excluding participants with diabetes, cancer and cardiovascular disease at baseline, for alternative versions of the plant-based diet indices (PDIs), in subgroup analysis by categories of potential confounders, and in latency analysis.

CONCLUSIONS

A healthful plant-based diet was associated with lower risk of frailty whereas an unhealthful plant-based diet was associated with higher risk.

Texturized Vegetable Protein as a Source of Protein Fortification of Wheat Buns

Increasing interest in plant-based proteins is particularly relevant in the food service sector. For specific groups, e.g., older adults, it may be challenging to ensure the consumption of protein of sufficient quality. One way of doing this could be through the fortification of a staple food such as bread. This study examined wheat buns, in which 0%, 20%, 35% and 50% of the flour was replaced with three different milled texturized vegetable proteins (TVP) of different plant protein combinations. Sensory and baking qualities were evaluated through sensory profiling and measurements of rising ability, baking loss, protein content and colour. An expert assessment and a robustness test were conducted to evaluate potential use in the food service sector. By substituting 35% of the wheat flour with milled TVP, it was possible to increase the protein content of the buns by 83% (up to 25% of DM) and still maintain an acceptable quality. The different TVPs showed that pea and faba bean or pea, faba bean and quinoa were more suitable in bread fortification than pea, faba bean and hemp. The study demonstrates the potential for producing quality bread for people who need a high protein intake in all their meals.

Nutritional Status and Habits among People on Vegan, Lacto/Ovo-Vegetarian, Pescatarian and Traditional Diets

Background: This study assessed the possible dependencies between nutritional habits and body composition among subjects with different dietary habits. Materials: A total of 196 healthy (aged 18−50 yrs) participants were enrolled in the study and divided into 4 groups according to their diet: vegans-VEGAN (n = 53), lacto/ovo-vegetarians—VEGE (n = 52), pescatarians-PESCA (n = 28), and omnivores-OMN (n = 43). Methods: The Food Frequency Questionnaire (FFQ) was used, and body composition was assessed on the In-Body120 analyzer. Results: Our result revealed in OMN + PESCA groups a higher average consumption frequency of sweets (p = 0.024), cheese/plant cheese (p < 0.001), eggs and egg dishes/egg substitutes (p < 0.001), butter, margarine/plant margarine (p < 0.001), cream /plant cream (p = 0.018), wine and cocktails (p = 0.028), vodka (p = 0.039) and lower of natural cottage cheese/tofu/tempeh (p < 0.001), vegetable oils (p = 0.036), legumes (p < 0.001) and nuts and seeds(p < 0.001) compared to the VEGAN + VEGE groups. The body composition analysis showed significant differences in skeletal muscle mass (SMM) (p = 0.019) and the content of minerals (p = 0.048) between groups. VEGAN disclosed the lowest average values of body fat mass (BFM), percentage body fat (PBF), and visceral adipose tissue (VAT) than other studied groups. Conclusions: The body composition analysis showed mean values within normal ranges in all of the groups, but some average results of OMN, PESCA, and VEGE compared to VEGAN were not highly satisfactory (in addition to eating behavior outcomes).

Diet Quality of Adolescents and Adults Who Completed the Australian Healthy Eating Quiz: An Analysis of Data over Six Years (2016-2022)

Diet quality is influenced by demographics and can change over time. This study aimed to (1) compare diet quality among adolescents/adults who completed the online Healthy Eating Quiz (HEQ) by demographic characteristics, and (2) to evaluate change in score over time for repeat completers. HEQ data collected between July 2016 and May 2022 were analysed, including demographics (age, gender, vegetarian status, socio-economic status, number of people main meals are shared with, country), and diet quality calculated using the Australian Recommended Food Score (ARFS) (range 0−73) for respondents aged ≥ 16 years. Differences in ARFS by demographic characteristics and change in score over time, adjusted for age, gender and vegetarian status, were tested by linear regression. The participants (n = 176,075) were predominantly female (70.4%), Australian (62.8%), and aged 18−24 years (27.7%), with 4.0% (n = 7087) repeat completers. Mean ± SD ARFS was 33.9 ± 9.4/73. Results indicate that ARFS was significantly lower among males and significantly higher with increasing age group, higher socio-economic status, in vegetarians, those who shared main meals with others, and those living in Australia (p-values < 0.001). Mean change in ARFS over time (2.3 ± 6.9) was significantly higher for those with lower baseline scores (p < 0.001). Publicly available, brief dietary assessment tools have the potential to improve diet quality at the population level.

Quality of Popular Diet Patterns in the United States: Evaluating the Effect of Substitutions for Foods High in Added Sugar, Sodium, Saturated Fat, and Refined Grains

Background

Many Americans have adopted popular diet patterns for general health improvement that restrict specific foods, macronutrients, or eating time. However, there is limited evidence to characterize the quality of these diet patterns.

Objectives

This study 1) evaluated the quality of popular diet patterns in the United States and 2) modeled the effect of targeted food substitutions on diet quality.

Methods

Dietary data from 34,411 adults ≥20 y old were acquired from the NHANES, 2005-2018. Dietary intake was assessed using the National Cancer Institute's usual intake methodology, and the Healthy Eating Index-2015 was used to evaluate diet quality. A diet model was used to evaluate the effect of targeted food substitutions on diet quality.

Results

A pescatarian diet pattern had the highest diet quality (65.2; 95% CI: 64.0, 66.4), followed by vegetarian (63.0; 95% CI: 62.0, 64.0), low-grain (62.0; 95% CI: 61.6, 62.4), restricted-carbohydrate (56.9; 95% CI: 56.6, 57.3), time-restricted (55.2; 95% CI: 54.8, 55.5), and high-protein (51.8; 95% CI: 51.0, 62.7) diet patterns. Modeled replacement of ≤3 daily servings of foods highest in added sugar, sodium, saturated fat, and refined grains with alternative foods led to an increase in diet quality and a decrease in energy intake for most diet patterns.

Conclusions

Low diet quality was observed for all popular diet patterns evaluated in this study. Modeled dietary shifts that align with recommendations to choose foods lower in added sugar, sodium, saturated fat, and refined grains led to modest improvements in diet quality and larger reductions of energy intake. Greater efforts are needed to encourage the adoption of dietary patterns that emphasize consumption of a variety of high-quality food groups.

Vegetarian and Vegan Diets: Beliefs and Attitudes of General Practitioners and Pediatricians in France

Studies suggest a decreasing trend in the consumption of meat products and a growing interest in vegetarian diets. Medical support may be relevant, especially when switching to a vegan diet. Our objective was to describe the beliefs and attitudes of primary care physicians toward vegetarian diets. A cross-sectional survey was conducted among general practitioners and pediatricians thorough a questionnaire including socio-demographic characteristics, specific care to vegetarians, and the risks and benefits of vegetarian diets according to physicians. Out of the 177 participating physicians, 104 (59%) have seen at least one vegetarian patient in consultation in the last three months. Half of the physicians declared that they would dissuade their patients from switching to a vegan diet (n = 88, 51%) and 14% (n = 24) from switching to an ovo-lacto-vegetarian (OLV) diet. Most physicians (n = 141, 88%) did not feel informed enough about these diets. Physicians thought that the most frequent deficiencies for OLV and vegan diets were iron (76% and 84%, respectively) and protein (45% and 79%, respectively). These results highlight the fact that French primary care physicians feel concerned by this subject and need more information on these diets. Specific recommendations would be useful to support their practice and relationship with vegetarians.

Application of a Modified Healthy Eating Index (HEI-Flex) to Compare the Diet Quality of Flexitarians, Vegans and Omnivores in Germany

Interest in plant-based nutrition has steadily increased in the western world in the recent years. The number of people following a meat-reduced, flexitarian diet is growing continuously. However, little is known about the diet quality of flexitarians compared to vegans or omnivores. Therefore, in this cross-sectional study, the food intake of 94 participants aged between 25–45 years was recorded via a validated food frequency questionnaire and 28 self-designed questions about the consumption of plant-based alternatives. An adapted Healthy Eating Index, HEI-flex, was developed to evaluate the diet quality of flexitarians, vegans and omnivores. Higher score points (SP) of the HEI-flex are associated with higher compliance with the official diet recommendations (V_max = 100 SP). Finally, flexitarians scored significantly more highly when compared to omnivores (54 ± 8 vs. 47 ± 9 SP; p = 0.008) but lower than vegans (54 ± 8 vs. 61 ± 10 SP; p = 0.010). The results showed that the HEI-flex is a useful tool for assessing and comparing the diet quality of flexitarians, vegans and omnivores. Despite the consumption of highly processed plant-based alternatives, reduction in meat and meat products seems to be accompanied by increased overall diet quality.

Dietary Patterns and Dietary Recommendations Achievement From Latin American College Students During the COVID-19 Pandemic Lockdown

This study aimed to compare the diet quality of different dietary patterns among college students from Latin American countries, including vegetarians, vegans, and omnivores during the COVID-19 pandemic. A cross-sectional, observational, multicenter study was conducted including a non- probabilistic sample of university students from 10 countries. University students were invited to participate in the study through social network platforms. Participants were self-reported to have followed a specific dietary pattern; either the Prudent diet, Western diet, Ovo-dairy-vegetarian diet, Fish-vegetarian diet, Strict vegetarian diet (vegan) or other. The last three patterns (vegetarians and vegans) were grouped as following a plant-based diet. A self-assessment survey was used to evaluate healthy eating habits using a questionnaire with values between 1 (do not consume) and 5 (consume) for a total of 9–45 points (higher values represent better eating habits). Unhealthy habits were assessed with nine questions. A total of 4,809 students filled out the questionnaire, and the majority of them were females (73.7%). A high percentage have been in lockdown for more than 5 months and were in lockdown when the survey was released. 74.3% were self-reported to follow a prudent diet, while 11.4% reported following a western dietary pattern and 8.8% a plant-based diet. When compliance with healthy and unhealthy dietary habits was analyzed, although all groups had low compliance, the plant-based diet group (56.09 ± 6.11) performed better than the Western diet group (48.03 ± 5.99). The total diet quality score was significantly higher for plant-based diet followers, who also tended to better achieve the recommendations than omnivorous students, especially the ones following a western diet. These results present evidence that young adults such as college-aged students have unhealthy dietary habits. However, the ones who follow a plant-based diet such as vegetarians and vegans exhibit better scores and healthier dietary conducts.

Higher protein intake during caloric restriction improves diet quality and attenuates loss of lean body mass

OBJECTIVE

Higher protein intake during weight loss is associated with better health outcomes, but whether this is because of improved diet quality is not known. The purpose of this study was to examine how the change in self-selected protein intake during caloric restriction (CR) alters diet quality and lean body mass (LBM).

METHODS

In this analysis of pooled data from multiple weight loss trials, 207 adults with overweight or obesity were examined before and during 6 months of CR (approximately 10 food records/person). Body composition was measured by dual-energy x-ray absorptiometry. Diet quality was assessed using the Healthy Eating Index in 2 groups: lower (LP) and higher (HP) protein intake.

RESULTS

Participants (mean [SD], 54 [11] years; 29 [4] kg/m² ) lost 5.0% (5.4%) of weight. Protein intake was 79 (9) g/d (1.0 [0.2] g/kg/d) and 58 (6) g/d (0.8 [0.1] g/kg/d) in the HP and LP groups, respectively (p < 0.05), and there was an attenuated LBM (kilograms) loss in the HP (-0.6% [1.5%]) compared with the LP (-1.2% [1.4%]) group (p < 0.01). The increased Healthy Eating Index score in the HP compared with the LP group was attributed to greater total protein and green vegetable intake and reduced refined grain and added-sugar intake (p < 0.05).

CONCLUSIONS

Increasing dietary protein during CR improves diet quality and may be another reason for reduced LBM, but it requires further study.

Human gut microbiota composition and its predicted functional properties in people with western and healthy dietary patterns

PURPOSE

Some dietary habits cluster together, and for this reason it is advised to study the impact of entire dietary patterns on human health, rather than that of individual dietary habits. The main objective of this study was to evaluate differences in gut microbiota composition and their predicted functional properties between people with a healthy (HDP) and western (WDP) dietary pattern.

METHODS

A cross-sectional, observational study was carried out on 200 participants enrolled 2017-2018 in Poznań, Poland, equally distributed into HDP and WDP groups. Diet was estimated using 3-day food records and information on stool transit times was collected. Fecal microbiota composition was assessed by 16S rRNA gene sequencing and its functional properties were predicted by the PICRUSt2 workflow.

RESULTS

The α-diversity did not differ between people with WDP and HDP, but β-diversity was associated with dietary pattern. People with HDP had higher relative abundances (RA) of Firmicutes and Faecalibacterium and lower RA of Bacteroidota and Escherichia-Shigella than participants with WDP. Only a small proportion of the variance in microbiota composition (1.8%) and its functional properties (2.9%) could be explained by dietary intake (legumes, simple sugars and their sources, like fruit, soft drinks) and stool transit characteristics.

CONCLUSION

Gut microbiota composition and predicted metabolic potential is shaped by overall diet quality as well as the frequency of defecation; however, the cumulative effect of these explain only a relatively low proportion of variance.

Vegetarianism, Microbiota and Cardiovascular health: Looking back, and forward

Cardiovascular diseases (CVD) are the leading cause of death globally, with over 17.9 million attributed deaths in 2019. Unhealthy diet is an often-overlooked major modifiable risk factor for CVD. Global Burden of Disease (GBD) estimates suggest that unhealthy diets account for nearly 26% of all deaths, of which 84% were attributed to CVD. Plant-based diets (PBDs), which are a diverse group of dietary patterns focused on plant produce, with flexibility for varying levels of vegetarianism, have been suggested to decrease the incidence of various cardiovascular and cardiometabolic diseases. In this review, we aim to delve into the spectrum of PBDs, revisit objective definitions and classifications, and compare them with standard non-vegetarian diets. We examine plausible mechanisms underlying the cardiovascular benefits of PBDs with a particular focus on the dietary manipulation of gut microbiota-host interaction and its effect on energy metabolism, and local and systemic inflammation. In addition, we explore the evidence on the impact of PBDs on cardiovascular disease, examine the challenges and limitations associated with dietary intervention studies, and devise strategies to draw valid conclusions. Dietary interventions, such as PBDs are one of the most powerful, attainable, cost-effective tools for health and environmental protection at the population level. We conclude with a clear appreciation for PBDs in environmental sustainability, climate change, and animal welfare.

Dietary Habits and Self-Reported Health Measures Among Norwegian Adults Adhering to Plant-Based Diets

Background

As plant-based diets is increasing, we aimed to investigate dietary habits, dietary motivation and self-reported health of Norwegian adults who adhere to different types of plant-based diets.

Methods

In 2020, 808 subjects (530 women and 278 men) participated in an online survey, including vegans (8%), lacto-ovo vegetarians (16%), pescatarians (23%), and flexitarians (53%).

Results

Half of the participants reported to consume fruits daily, three quarters consumed vegetables daily, and one quarter consumed whole grain products daily. Half of the participants reported weekly consumption of sweets and salted snacks, and 10% reported daily consumption of sugary drinks. Daily consumption of milk and dairy substitutes were reported by vegans (49%), lacto-ovo vegetarians (33%), pescatarians (32%), and flexitarians (25%). Daily consumption of meat replacement products was reported by vegans (3%), lacto-ovo vegetarians (5%), pescatarians (2%). Reported supplement use was highest among vegans (62%) and lowest among flexitarians (28%). Dietary motivations were driven by environmental (71%), health (64%), and animal welfare (49%) concerns, across all dietary groups. 75% reported their self-perceived health to be good or very good.

Conclusion

We found that Norwegian adults adhering to plant-based diets consumed less fruit, vegetables, and whole grain products, together with more sugar than recommended in the Norwegian dietary guidelines. The participants reported their self-perceived health to be good or very good.

When conflicts get heated, so does the planet: coupled social-climate dynamics under inequality

Climate dynamics are inextricably linked to processes in social systems that are highly unequal. This suggests a need for coupled social-climate models that capture pervasive real-world asymmetries in the population distribution of the consequences of anthropogenic climate change and climate (in)action. Here, we use evolutionary game theory to develop a social-climate model with group structure to investigate how anthropogenic climate change and population heterogeneity coevolve. We find that greater homophily and resource inequality cause an increase in the global peak temperature anomaly by as much as 0.7°C. Also, climate change can structure human populations by driving opinion polarization. Finally, climate mitigation achieved by reducing the cost of mitigation measures paid by individuals tends to be contingent upon socio-economic conditions, whereas policies that achieve communication between different strata of society show climate mitigation benefits across a broad socio-economic regime. We conclude that advancing climate change mitigation efforts can benefit from a social-climate systems perspective.