Effects of an Ad Libitum Consumed Low-Fat Plant-Based Diet Supplemented with Plant-Based Meal Replacements on Body Composition Indices

A Review of Plant-Based Diets for Obesity Management

OBJECTIVE

Obesity is the most prevalent chronic disease in the United States with over 70% of the American population suffering from overweight/obesity. Recently, the popularity of plant-based diets (PBDs) has grown, with individuals adopting these diets for ethical, health and environmental reasons. Our aim is to evaluate the effect of a PBD on weight loss among patients who are overweight or obese.

METHODS

A literature review of PBDs for the treatment of obesity was conducted using PubMed and Scopus. Our search yielded 27 intervention trials (3361 participants) and 6 metanalyses (9168 participants, 61 trials).

RESULTS

Among the intervention trials evaluated, 75% showed a significant increase in weight loss or decrease in weight in the intervention group, on average -5.0 kg (range -1.8 to -12.1 kg). Other outcomes included energy intake (-420 Kcal/d), systolic blood pressure (-3.78 mmHg), fasting plasma glucose (-2.0 mmol/L), hemoglobin A1c (-0.5%, -3.4 mmol/L), total cholesterol (-0.40 mmol/L), low-density lipoprotein (-0.38 mmol/L), triglyceride levels (+0.13 mmol/L), and fiber intake (+10.8 g/d). The 6 meta-analyses showed weight loss (average -2.9 kg, range -2.02 kg to -4.1 kg), body mass index reduction, and improvements in hemoglobin A1c, low-density lipoprotein, and total cholesterol.

CONCLUSION

PBDs result in significant weight loss and improve metabolic outcomes. PBDs offer a sustainable approach to long-term weight loss maintenance. Health care providers should encourage open discussions with their patients regarding their dietary habits to assist them in setting feasible lifestyle goals and consider shared medical appointments to support patients in transitioning to PBDs.

Bone mineral density and body composition in Australians following plant-based diets vs. regular meat diets

Background and aims

Bone mineral density (BMD) and body composition play an important role in maintaining metabolic health and physical functioning. Plant-based diets (PBDs) are known to be lower in protein and calcium, which can impact BMD and body composition. This study aimed to investigate the relationship between various PBDs compared to regular meat diet and whole-body BMD, body composition, and weight status.

Methods

A cross-sectional study was conducted with adults (n = 240) aged 30-75 years, who habitually followed dietary patterns: vegan, lacto-vegetarian, pesco-vegetarian, semi-vegetarian, or regular meat eater (48 per group). Parameters were measured using dual-energy x-ray absorptiometry (DXA), and multivariable regression analyses were used to adjust for lifestyle confounders, socioeconomic factors, and BMI.

Results

After adjustments, whole-body BMD and body composition were not significantly different between those following PBDs and regular meat diets, except for lacto-ovo vegetarians, who had significantly lower lean mass by -1.46 kg (CI: -2.78, -0.13). Moreover, lacto-ovo vegetarians had a significantly lower T-score by -0.41 SD (CI: -0.81, -0.01) compared to regular meat eaters. Waist circumference was significantly lower in individuals adhering to a PBD compared to a regular meat diet: vegans by -4.67 cm (CI: -8.10, -1.24), lacto-ovo vegetarians by -3.92 cm (CI: -6.60, -1.23), pesco-vegetarians by -3.24 cm (CI: -6.09, -0.39), and semi-vegetarians by -5.18 cm (CI: -7.79, -2.57). There were no significant differences in lean mass (%), fat mass (% and total), android/gynoid measures, body weight, or BMI across dietary patterns. All dietary patterns met the recommended dietary intake for calcium and protein, and 25-hydroxy-vitamin D status was comparable across groups.

Conclusions

This cross-sectional study found that adhering to a PBD characterized by varying degrees of dairy and meat restriction is not associated with meaningful changes in BMD or body composition, provided that the dietary patterns are planned appropriately with adequate levels of calcium and protein.

Reply to Benedik et al. Comment on "Jakše et al. Vegan Diets for Children: A Narrative Review of Position Papers Published by Relevant Associations. Nutrients 2023, 15, 4715"

Benedik et al [...].

The Effects of an Eight-Week Swimming Program on Body Composition and Assessment of Dietary Intake in Post-COVID-19 Patients

COVID-19 infection and its consequences (long-term COVID-19 syndrome) have implications for weight loss, body composition, and diet quality. In the context of the "PostCovSwim" project, which is part of a broader international study, the impact of an eight-week swimming program on post-COVID-19 patients' nutritional status (i.e., body composition and dietary intake) was evaluated. Body composition and dietary intake were assessed by medically approved and calibrated bioelectrical impedance (Tanita 780 S MA) and food frequency questionnaires. At the baseline, most participants were classified as overweight based on their body mass index (BMI). However, their body fat percentage (BF%) classification indicated normal weight, although females were near obesity thresholds. Furthermore, at the baseline, according to the BMI classification, 62% of females and 61% of males were female, whereas according to the BF% for obesity classification, 44% of females and 43% of males were considered overweight or obese. Surprisingly, despite the eight-week program, there were no significant changes in body composition. Additionally, the assessment of dietary intake, which remained consistent throughout the study, revealed dietary imbalances characterized by an unhealthy low-carbohydrate, high-fat dietary pattern. This dietary pattern entailed excessive consumption of ultraprocessed foods; reduced carbohydrate intake (39% E vs. 37% E); increased total fat intake (46% E vs. 47% E); increased saturated fatty acids (14% E vs. 13% E); increased cholesterol (412 mg/d vs. 425 mg/d); increased free sugars (7% E vs. 7% E); and inadequate intake of fibre (24 g/d vs. 20 g/d), polyunsaturated fatty acids (6.6% E vs. 7.7% E), vitamin B12 (in females: 3.1 µg/d), vitamin C (86 mg/d vs. 66 mg/d), vitamin D (2 µg/d vs. 3.2 µg/d), folate (in males: 258 µg/d), calcium (777 mg/d vs. 743 mg/d), and selenium (in males: 66 µg/d). After an eight-week swimming program following COVID-19, no significant changes were observed in the subjects' body composition. Their dietary intake was found to not align with the dietary recommendations. These findings underscore the urgency of implementing comprehensive dietary and lifestyle interventions for post-COVID-19 patients to optimize their recovery and overall well-being. Physical activity, like a swimming program, may positively affect various aspects of human well-being.

Lifestyle Medicine Implementation in 8 Health Systems: Protocol for a Multiple Case Study Investigation

BACKGROUND

Lifestyle medicine (LM) is the use of therapeutic lifestyle changes (including a whole-food, plant-predominant eating pattern; regular physical activity; restorative sleep; stress management; avoidance of risky substances; and positive social connection) to prevent and treat chronic illness. Despite growing evidence, LM is still not widely implemented in health care settings. Potential challenges to LM implementation include lack of clinician training, staffing concerns, and misalignment of LM services with fee-for-service reimbursement, but the full range of factors facilitating or obstructing its implementation and long-term success are not yet understood. To learn important lessons for success and failure, it is crucial to understand the experiences of different LM programs.

OBJECTIVE

This study aims to describe in depth the protocol used to identify barriers and facilitators impacting the implementation of LM in health systems.

METHODS

The study team comprises team members at the American College of Lifestyle Medicine (ACLM), including staff and researchers with expertise in public health, LM, and qualitative research. We recruited health systems that were members of the ACLM Health Systems Council. From among 15 self-nominating health systems, we selected 7 to represent a diversity of geographic location, type, size, expertise, funding, patients, and LM services. Partway through the study, we recruited 1 additional contrasting health system to serve as a negative case. For each case, we conducted in-depth interviews, document reviews, site visits (limited due to the COVID-19 pandemic), and study team debriefs. Interviews lasted 45-90 minutes and followed a semistructured interview guide, loosely based on the Consolidated Framework for Implementation Research (CFIR) model. We are constructing detailed case narrative reports for each health system that are subsequently used in cross-case analyses to develop a contextually rich and detailed understanding of various predetermined and emergent topics. Cross-case analyses will draw on a variety of methodologies, including in-depth case familiarization, inductive or deductive coding, and thematic analysis, to identify cross-cutting themes.

RESULTS

The study team has completed data collection for all 8 participating health systems, including 68 interviews and 1 site visit. We are currently drafting descriptive case narratives, which will be disseminated to participating health systems for member checking and shared broadly as applied vignettes. We are also conducting cross-case analyses to identify critical facilitators and barriers, explore clinician training strategies to facilitate LM implementation, and develop an explanatory model connecting practitioner adoption of LM and experiences of burnout.

CONCLUSIONS

This protocol paper offers real-world insights into research methods and practices to identify barriers and facilitators to the implementation of LM in health systems. Findings can advise LM implementation across various health system contexts. Methodological limitations and lessons learned can guide the execution of other studies with similar methodologies.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/51562.

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.

Plant-based diets and body composition in Chinese omnivorous children aged 6-9 years old: A cross-sectional study

Evidence suggests that plant-based diets are beneficial for alleviating metabolic diseases. Childhood is a crucial period for body growth and development. However, it is unknown whether adherence to a plant-based diet is related to a healthy body composition in children. We aimed to assess the relationship between a plant-based diet and body composition in children. A total of 452 Chinese children aged 6–9 years old participated in this cross-sectional study. Lean mass (LM), fat mass, and fat mass percentage (FMP) were assessed via dual-energy X-ray absorptiometry. An age- and sex-specific abdominal FMP ≥85th percentile was defined as abdominal obesity. Handgrip strength was measured using a hydraulic hand dynamometer. A validated 79-item food frequency questionnaire was used to collect dietary information. Overall plant-based diet index (PDI), healthful plant-based diet index (hPDI), and unhealthful plant-based diet index (uPDI) scores were calculated. After adjusting for potential covariates, a higher hPDI score (per 10-score increment) was associated with a higher LM in the android area (0.038 kg, 3.2%), gynoid area (0.048 kg, 1.9%), and trunk (0.102 kg, 1.2%) and with a lower FMP (1.18%) in the android area. In contrast, a higher uPDI score (per 10-score increment) was associated with a lower LM in the trunk (0.091 kg, 1.1%) and android area (0.023 kg, 1.9%) and with a higher FMP (0.74%) in the android area. No significant associations were observed between the overall PDI and body composition or abdominal obesity. After stratifying by sex, higher (vs. lower) hPDI scores was associated with lower abdominal obesity risk in girls and higher handgrip strength in boys. In conclusion, in this cross-sectional study, we found that stronger adherence to a healthful plant-based diet, and less adherence to an unhealthful plant-based diet was associated with better body composition in Chinese omnivorous children aged 6–9 years old. Our results highlight the need to distinguish between healthy and unhealthy plant foods within investigating how to obtain a healthy body composition in children.

Comparison between Different Groups of Vegetarianism and Its Associations with Body Composition: A Literature Review from 2015 to 2021

BACKGROUND

Vegetarian and vegan diets have become increasingly popular in the last years for many reasons, including their association with various health benefits when compared to omnivorous diets. The main objective of the study was to collect recent (2015-2021) scientific evidence for potential implications between a vegetarian/vegan diet and an individuals' body composition.

METHODS

A literature search was conducted in PubMed, with 22 studies selected for inclusion in our collective evaluation. Of the 22 studies included, there were 12 randomized controlled trials, 1 nonrandomized controlled trial, 1 comparative study, and 8 cross-sectional. The overall sample included in this study consists of 436,178 participants, 10,090 of whom were vegetarians, 5044 vegans, and 421,044 omnivores.

RESULTS

Most studies, 17 out of 22, reported a significant positive relationship between a plant-based diet and body composition.

CONCLUSION

There is scientifically sound evidence that vegan or vegetarian diets are associated with weight and body mass index reduction and, in some cases, fat mass distribution changes.

Placing a Well-Designed Vegan Diet for Slovenes

Interest in vegan diets has increased globally as well as in Slovenia. The quantity of new scientific data requires a thorough synthesis of new findings and considerations about the current reserved position of the vegan diet in Slovenia. There is frequently confusion about the benefits of vegetarian diets that are often uncritically passed on to vegan diets and vice versa. This narrative review aims to serve as a framework for a well-designed vegan diet. We present advice on how to maximize the benefits and minimize the risks associated with the vegan diet and lifestyle. We highlight the proper terminology, present the health effects of a vegan diet and emphasize the nutrients of concern. In addition, we provide guidance for implementing a well-designed vegan diet in daily life. We conducted a PubMed search, up to November 2021, for studies on key nutrients (proteins, vitamin B12, vitamin D, omega-3 long chain polyunsaturated fatty acids (eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)), calcium, iron, zinc, iodine and selenium) in vegan diets. Given the limited amount of scientific evidence, we focus primarily on the general adult population. A well-designed vegan diet that includes a wide variety of plant foods and supplementation of vitamin B12, vitamin D in the winter months and potentially EPA/DHA is safe and nutritionally adequate. It has the potential to maintain and/or to improve health. For physically active adult populations, athletes or individuals with fast-paced lifestyles, there is room for further appropriate supplementation of a conventional vegan diet according to individuals' health status, needs and goals without compromising their health. A healthy vegan lifestyle, as included in government guidelines for a healthy lifestyle, includes regular physical activity, avoidance of smoking, restriction of alcohol and appropriate sleep hygiene.

Lifestyle Medicine and Economics: A Proposal for Research Priorities Informed by a Case Series of Disease Reversal

Chronic disease places an enormous economic burden on both individuals and the healthcare system, and existing fee-for-service models of healthcare prioritize symptom management, medications, and procedures over treating the root causes of disease through changing health behaviors. Value-based care is gaining traction, and there is a need for value-based care models that achieve the quadruple aim of (1) improved population health, (2) enhanced patient experience, (3) reduced healthcare costs, and (4) improved work life and decreased burnout of healthcare providers. Lifestyle medicine (LM) has the potential to achieve these four aims, including promoting health and wellness and reducing healthcare costs; however, the economic outcomes of LM approaches need to be better quantified in research. This paper demonstrates proof of concept by detailing four cases that utilized an intensive, therapeutic lifestyle intervention change (ITLC) to dramatically reverse disease and reduce healthcare costs. In addition, priorities for lifestyle medicine economic research related to the components of quadruple aim are proposed, including conducting rigorously designed research studies to adequately measure the effects of ITLC interventions, modeling the potential economic cost savings enabled by health improvements following lifestyle interventions as compared to usual disease progression and management, and examining the effects of lifestyle medicine implementation upon different payment models.

Whole-Food Plant-Based Lifestyle Program and Decreased Obesity

Failure of weight-loss programs is high. We evaluated a whole-food plant-based (WFPB) lifestyle program. We investigated the obesity indices of 151 healthy adults who were on our ongoing, community-based program for the short (0.5 to ≤2 years), medium (2 to ≤5 years), or long term (5 to 10 years). Body composition indices were measured by medically approved bioimpedance. Body composition changes were favorable for all 3 groups and both genders. There were no differences in body composition between the males for all 3 groups, while there were lower body mass (BM), body mass index (BMI), and muscle mass in females on long-term versus short-term programs. All participants experienced a decrease in BMI (−2.5 kg/m2), BM (−7.1 kg), and body fat percentage (−6.4%; P < .001 for all). The reductions for those with a baseline BMI of obese, overweight, and normal were −5.6, −2.4, and −0.9 kg/m2 for BMI, −16.1, −7.1, and −2.5 kg for total BM, and −9.5%, −6.6%, and −4.8% for body fat percentage (baseline vs current; P < .001 for all). A total of 86% of parents of underage children introduced the WFPB lifestyle to children. Our WFPB lifestyle program provides a long-term reversal of obesity.

Characteristics of Slovenian Adults in Community-Based Whole-Food Plant-Based Lifestyle Program

Objective

Adopting a plant-based diet (PBD) and lifestyle is healthy, sustainable, and increasingly popular, while also demanding. Individuals might face challenges to maintain this lifestyle. We aimed to determine the anthropometric values and lifestyle factors and motives of adults to adopt a whole-food, plant-based (WFPB) lifestyle by joining our ongoing, community-based, WFPB lifestyle program 0.5-10 years ago.

Methods

We measured body mass index (BMI) and body fat percentage status (BF%) using bioimpedance. Lifestyle status was obtained by standardized electronic questionnaires. For evaluating the motives for following strict PBD, the participants were asked to rank 8 different motives (i.e., 8: the most-, 1: the least important). Setting. A cross-sectional study in Slovenia. Participants. A total of 151 healthy adults with an average age of 39.6 years (SD: 12.5 years).

Results

The participants had an average BMI of 23.9 kg/m² (SD: 3.8 kg/m²) and an average BF% of 22.3% (SD: 7.3%), were physically very active, with an average Long International Physical Activity Questionnaire (L-IPAQ) score of 5541.2 metabolic equivalents (METs) min/week (SD: 4677.0 METs min/week), having good sleep quality, with an average Pittsburgh Sleep Quality Index (PSQI) score of 2.7 (SD: 1.8), perceiving low stress, and with an average Perceived Stress Questionnaire (PSQ) score of 0.29 (SD: 0.1). We discovered no significant differences in lifestyle between participants who were involved in our WFPB lifestyle program for short, medium, or long periods of time. The motives for WFPB lifestyle included health benefits (score: 7.9/8), body mass management (6.3), eating to satiety (4.9), convenience (4.3), environmental concerns (4.1), affordability (3.7), animal ethics (3.6), and religious reasons (1.1).

Conclusion

A WFPB lifestyle program for any length of time that includes an extensive support system provides favorable, long-term lifestyle changes.

Nutrient and Food Intake of Participants in a Whole-Food Plant-Based Lifestyle Program

OBJECTIVE

We evaluated the nutrient adequacy of a well-planned supplemented whole-food plant-based (WFPB) diet as a component of an ongoing community lifestyle optimization program. We investigated the contributions of nutrients from foods and supplements and plant-based meal replacement (SMR) separately (foods, SMR) and combined (vs recommendations) as well as food group intake, both according to sex.

METHOD

Our cross-sectional study included 151 healthy, active participants (aged 39.6 years) who were on a Western-type diet when they voluntarily joined our WFPB lifestyle program (0.5-10 years ago). We assessed diet using 3-day weighed dietary records (foods, S, and MR). After we standardized nutrient intake to 2000 kcal/d, we calculated the contribution of macro- and micronutrients from foods and SMR separately and combined (foods + SMR) (vs central European Recommendations), as well as food group intake, both according to sex.

RESULTS

All macro- and micronutrient intake (total: from foods plus SMR) exceeded the reference values, except for calcium (95% and 82% in females and males) and vitamin D (both sexes, in summertime). Compared with male participants, female participants consumed (i.e., from foods and SMR together) significantly larger amounts of 23 (/25) micronutrients (8 [/25] from foods and 22 [/25] from SMR). The diet was primarily composed of the following (by mass in descending order): unprocessed vegetables/fruits, whole grains, legumes, potatoes, nuts/seeds, MR, and spices/herbs.

CONCLUSIONS

Participants in our WFPB lifestyle program ingested a nutrient-rich WFPB diet and targeted supplementation. The presented ongoing community WFPB lifestyle program ensures a healthy, balanced, and environment-friendly dietary pattern for participants who are compliant.

Effects of Plant-Based Diets on Weight Status: A Systematic Review

There is an increasing number of people who convert to a plant-based diet. The desire for health benefits, including weight management, is often a contributing factor behind this dietary choice. The purpose of this review was to evaluate intervention studies assessing the effects of different plant-based diets on body mass index and weight. A literature search was conducted in PubMed until December 2019. Twenty-two publications from 19 studies were included. The majority of them were randomized controlled trials comparing a low-fat vegan diet to an omnivore diet in participants with overweight, type 2 diabetes mellitus and/or cardiovascular disease. All studies reported weight reductions, of which seven revealed significant differences, and four revealed non-significant differences between the intervention and the control groups. The results suggest that plant-based diets may improve weight status in some patient groups. Due to restrictions in fat intake in many studies, followed by reduced energy intake, the effects of the different interventions differ depending on the specific plant-based diets investigated. Future research should aim to include a representative study population and apply study diets without dietary restrictions.

Dietary Intakes and Cardiovascular Health of Healthy Adults in Short-, Medium-, and Long-Term Whole-Food Plant-Based Lifestyle Program

An effective lifestyle strategy to reduce cardiovascular diseases risk (CVD) factors is needed. We examined the effects of a whole-food plant-based (WFPB) lifestyle program on dietary intake and cardiovascular (CV) risk factors in 151 adults (mean 39.6 (SD 12.5) years). Adherence was categorised into short-, medium- and long-term (years: (0.5-<2), (2-<5) and (5-10)), for both genders separately. Dietary intakes were assessed, fasting blood lipids and blood pressure (BP) were measured, and % participants reaching guideline recommended targets for LDL-cholesterol, triglycerides and BP in the primary CVD prevention was assessed. There were no statistically significant differences in intakes of energy and most nutrients among participants (both genders), that were short-, medium- and long term in our program. Diet was mainly composed of unprocessed vegetables/fruits, whole grains, legumes, potatoes, and nuts/seeds. LDL-cholesterol, triglycerides, systolic and diastolic BP were within targets for: 93%, 97%, 88% and 95% participants, respectively. In females (vs. males), total- and HDL-cholesterol were higher (mean): 3.8 (SD 0.7) vs. 3.4 (SD 0.9), p = 0.002 and 1.5 (SD 0.3) vs. 1.1 (SD 0.2) mmol/L, p < 0.001), systolic BP was lower (113 (SD 11) vs. 120 (SD 10) mmHg, p = 0.001), while there was no difference in diastolic BP (71 (SD 9) vs. 72 (SD 8) mmHg, p = 0.143). More females vs. males reached target triglycerides (99% vs. 91%, p = 0.021) and systolic BP (92% vs. 79%, p = 0.046), while similar females and males reached target LDL-cholesterol (94% vs. 91%, p = 0.500) and diastolic BP (93% vs. 100%, p = 0.107). Participation in our WFPB lifestyle program is associated with favourable dietary intakes, safety markers, and CV risk factor profiles.

Scientific evidence of diets for weight loss: Different macronutrient composition, intermittent fasting, and popular diets

New dietary strategies have been created to treat overweight and obesity and have become popular and widely adopted. Nonetheless, they are mainly based on personal impressions and reports published in books and magazines, rather than on scientific evidence. Animal models and human clinical trials have been employed to study changes in body composition and metabolic outcomes to determine the most effective diet. However, the studies present many limitations and should be carefully analyzed. The aim of this review was to discuss the scientific evidence of three categories of diets for weight loss. There is no one most effective diet to promote weight loss. In the short term, high-protein, low-carbohydrate diets and intermittent fasting are suggested to promote greater weight loss and could be adopted as a jumpstart. However, owing to adverse effects, caution is required. In the long term, current evidence indicates that different diets promoted similar weight loss and adherence to diets will predict their success. Finally, it is fundamental to adopt a diet that creates a negative energy balance and focuses on good food quality to promote health.

Effects of ad libitum consumed, low-fat, high-fiber plant-based diet supplemented with plant-based meal replacements on cardiovascular risk factors

Background

Sustainable nutritional strategies to reduce risk factors of cardiovascular diseases are highly needed. Inclusion of meal replacements may increase adherence to plant-based diets (PBDs).

Objective

The aim of this study was to test the effects of a transition from a western-type diet to a new nutritional paradigm with a PBD from predominately unrefined whole food sources, eaten ad libitum and including nutrient-enriched plant-based meal replacements twice daily.

Design

This was a single-arm, prospective interventional trial for 10 weeks in 36 participants with extension to 36 weeks in 18 participants. The main endpoint was serum low-density lipoprotein (LDL)-cholesterol measured at baseline, after 10 weeks (phase 1), and after 36 weeks (phase 2). Secondary endpoints included total, non-high-density lipoprotein (HDL) and HDL-cholesterol, fasting glucose, uric acid, and insulin-like growth factor-1 (IGF-1).

Results

The mean reduction in LDL-cholesterol was 0.6 (95% confidence interval [CI], 0.3–0.8) mmol/L (−15%, P < 0.001) at the end of phase 1, with no further change by the end of phase 2. Similar reductions were noted for non-HDL-cholesterol and total cholesterol. HDL-cholesterol was reduced by 0.16 mmol/L (95% CI, 0.1–0.2). There was a borderline reduction in fasting glucose (5.2 to 5 mmol/L in phase 1, P = 0.08) and a small significant rise in serum uric acid levels of 15 (95% CI, 1–28) μmol/L, P < 0.05. Median baseline value for IGF-1 concentration was 156 μg/L. Participants with baseline IGF-1 below median had a significant increase in IGF-1 value from baseline 110 ± 31 to 132 ± 39 at the end of phase 1 (mean change of +22 μg/L, 95% CI, 11–33, P = 0.001). Participants with baseline IGF-1 above median had no significant change in IGF-1. Significant reductions in body weight, body fat, and visceral fat were observed.

Conclusions

Supplemented, unrefined PBD eaten ad libitum was effective in improving total and LDL-cholesterol, non-HDL-cholesterol, and IGF-1 in low baseline IGF-1 subgroup.

This trial is registered as NCT02905448 at https://clinicaltrials.gov, registered 19.9.2016, https://clinicaltrials.gov/ct2/show/NCT02905448.

A Plant-Based High-Carbohydrate, Low-Fat Diet in Overweight Individuals in a 16-Week Randomized Clinical Trial: The Role of Carbohydrates

The effects of carbohydrates on body weight and insulin sensitivity are controversial. In this 16-week randomized clinical trial, we tested the role of a low-fat, plant-based diet on body weight, body composition and insulin resistance. As a part of this trial, we investigated the role of changes in carbohydrate intake on body composition and insulin resistance. Participants (n = 75) were randomized to follow a plant-based high-carbohydrate, low-fat (vegan) diet (n = 38) or to maintain their current diet (n = 37). Dual-energy X-ray absorptiometry was used to measure body composition. Insulin resistance was assessed with the Homeostasis Model Assessment (HOMA-IR) index. A repeated measure ANOVA model was used to test the between-group differences from baseline to 16 weeks. A linear regression model was used to test the relationship between carbohydrate intake, and body composition and insulin resistance. Weight decreased significantly in the vegan group (treatment effect -6.5 [95% CI -8.9 to -4.1] kg; Gxt, p < 0.001). Fat mass was reduced in the vegan group (treatment effect -4.3 [95% CI -5.4 to -3.2] kg; Gxt, p < 0.001). HOMA-IR was reduced significantly in the vegan group (treatment effect -1.0 [95% CI -1.2 to -0.8]; Gxt, p = 0.004). Changes in consumption of carbohydrate, as a percentage of energy, correlated negatively with changes in BMI (r = -0.53, p < 0.001), fat mass (r = -0.55, p < 0.001), volume of visceral fat (r = -0.35, p = 0.006), and HOMA (r = -0.27, p = 0.04). These associations remained significant after adjustment for energy intake. Changes in consumption of total and insoluble fiber correlated negatively with changes in BMI (r = -0.43, p < 0.001; and r = -0.46, p < 0.001, respectively), fat mass (r = -0.42, p < 0.001; and r = -0.46, p < 0.001, respectively), and volume of visceral fat (r = -0.29, p = 0.03; and r = -0.32, p = 0.01, respectively). The associations between total and insoluble fiber and changes in BMI and fat mass remained significant even after adjustment for energy intake. Increased carbohydrate and fiber intake, as part of a plant-based high-carbohydrate, low-fat diet, are associated with beneficial effects on weight, body composition, and insulin resistance.

Weight Loss in Advanced Chronic Kidney Disease: Should We Consider Individualised, Qualitative, ad Libitum Diets? A Narrative Review and Case Study

In advanced chronic kidney disease, obesity may bring a survival advantage, but many transplant centres demand weight loss before wait-listing for kidney graft. The case here described regards a 71-year-old man, with obesity-related glomerulopathy; referral data were: weight 110 kg, Body Mass Index (BMI) 37 kg/m², serum creatinine (sCr) 5 mg/dL, estimated glomerular filtration rate (eGFR) 23 mL/min, blood urea nitrogen (BUN) 75 mg/dL, proteinuria 2.3 g/day. A moderately restricted, low-protein diet allowed reduction in BUN (45–55 mg/dL) and good metabolic and kidney function stability, with a weight increase of 6 kg. Therefore, he asked to be enrolled in a weight-loss program to be wait-listed (the two nearest transplant centres required a BMI below 30 or 35 kg/m²). Since previous low-calorie diets were not successful and he was against a surgical approach, we chose a qualitative, ad libitum coach-assisted diet, freely available in our unit. In the first phase, the diet is dissociated; he lost 16 kg in 2 months, without need for dialysis. In the second maintenance phase, in which foods are progressively combined, he lost 4 kg in 5 months, allowing wait-listing. Dialysis started one year later, and was followed by weight gain of about 5 kg. He resumed the maintenance diet, and his current body weight, 35 months after the start of the diet, is 94 kg, with a BMI of 31.7 kg/m², without clinical or biochemical signs of malnutrition. This case suggests that our patients can benefit from the same options available to non-CKD (chronic kidney disease) individuals, provided that strict multidisciplinary surveillance is assured.