Effects of acute exercise and exercise training on plasma GDF15 concentrations and associations with appetite and cardiometabolic health in individuals with overweight or obesity - A secondary analysis of a randomized controlled trial.

Growth Differentiation Factor 15 (GDF15) is seemingly involved in appetite control. Acute exercise increases GDF15 concentrations in lean humans, but acute and long-term effects of exercise on GDF15 in individuals with overweight/obesity are unknown. We investigated the effects of acute exercise and exercise training on GDF15 concentrations in individuals with overweight/obesity and associations with appetite and cardiometabolic markers. 90 physically inactive adults (20-45 years) with overweight/obesity were randomized to 6-months habitual lifestyle (CON, n=16), or isocaloric exercise of moderate (MOD, n=37) or vigorous intensity (VIG, n=37), 5 days/week. Testing was performed at baseline, 3, and 6 months. Plasma GDF15 concentrations, other metabolic markers, and subjective appetite were assessed fasted and in response to acute exercise before an ad libitum meal. Cardiorespiratory fitness, body composition, insulin sensitivity, and intraabdominal adipose tissue were measured. At baseline, GDF15 increased 18% (95%CI: 4; 34) immediately after acute exercise and 32% (16; 50) 60 min post-exercise. Fasting GDF15 increased 21% (0; 46) in VIG after 3 months (p=0.045), but this attenuated at 6 months (13% (-11; 43), p=0.316) and was unchanged in MOD (11% (-6; 32), p=0.224, across 3 and 6 months). Post-exercise GDF15 did not change in MOD or VIG. GDF15 was not associated with appetite or energy intake. Higher GDF15 was associated with lower cardiorespiratory fitness, central obesity, dyslipidemia, and poorer glycemic control. In conclusion, GDF15 increased in response to acute exercise but was unaffected by exercise training. Higher GDF15 concentrations were associated with a less favorable cardiometabolic profile but not with markers of appetite. This suggests that GDF15 increases in response to acute exercise independent of training state. Whether this has an impact on free-living energy intake and body weight management needs investigation.

Human Gastrointestinal Transit and Hormonal Response to Different Meal Types: A Randomized Crossover Study.

BACKGROUND: The wireless motility capsule (WMC) technique is a noninvasive and radiation-free method for measuring regional and whole gut transit in response to ingestion of a granola bar (SmartBar) or an eggbeater meal. The WMC has the potential to measure gastrointestinal transit in metabolic research as part of a standardized mixed meal tolerance test. OBJECTIVES: To evaluate gastrointestinal transit with the WMC and postprandial plasma/serum concentrations of metabolites and gastrointestinal hormones as well as subjective appetite following ingestion of a SmartBar compared with a standardized mixed meal. METHODS: Fourteen healthy participants [3 men, median (IQR) age 53.8 (45.8; 64.50) y, body weight 63.9 (59.9; 69.7) kg, BMI 23.1 (21.8; 23.9) kg/m2] completed a 2-d crossover study. Following ingestion of either a SmartBar (260 kcal, 7 energy percent (E%) fat, 74E% carbohydrate, and 19E% protein) or a standardized mixed meal (498 kcal, 34E% fat, 49E% carbohydrate, and 17E% protein), participants swallowed the WMC. Blood samples were drawn in the fasted state and postprandially for analyses of gastrointestinal hormones and metabolites. The primary outcome was difference in gastric emptying time between the 2 test days. Wilcoxon signed rank tests were used to test differences between test days. RESULTS: Median (IQR) gastric emptying time was 98.0 (70.0; 113.0) min longer (P = 0.001) and incremental area under the curve of triglyceride, glucose-dependent insulinotropic polypeptide, and peptide YY were 40 mmol/L × min, 45.7%, and 63.7% greater after the standardized mixed meal compared with the SmartBar (all P < 0.001). CONCLUSIONS: The WMC can be used in combination with a standardized mixed meal for evaluation of gastrointestinal transit in healthy men and women. Gastric emptying time was prolonged in response to the standardized mixed meal whereas transit times of the small bowel, colon, and whole gut did not differ between the test meals.

Predicting Food Intake from Food Reward and Biometric Responses to Food Cues in Adults with Normal Weight Using Machine Learning.

BACKGROUND: Eating behaviors are determined by a complex interplay between behavioral and physiologic signaling occurring before, during, and after eating. OBJECTIVES: The aim was to explore how selected behavioral and physiologic variables separately and grouped together predicted intake of 8 different foods. METHODS: One hundred adults with normal weight performed a food preference task combined with biometric measurements (the Steno Biometric Food Preference Task) in the fasting state. The task measured food reward as well as biometric (eye tracking, electrodermal activity, and facial expressions) responses to images of foods varying in fat content and taste. Energy intake from an ad libitum buffet of the same 8 foods as assessed in the preference task was subsequently assessed. A mixed-effects random forest approach was applied to explore how individual and combined measures of food reward and biometric responses predicted energy intake of the 8 single foods. The performance of the different prediction models was compared with the predictions from a linear model including only an intercept (naïve model) using bootstrap cross-validation. RESULTS: Participants had a median [IQR] intake of 369 kJ [126-472 kJ] per food. Combined or separate measures of food reward or biometric responses did not predict energy intake better than the naïve model. CONCLUSIONS: We did not find that the reward or biometric responses to food cues assessed in a clinical setting were useful in predicting energy intake of single foods. However, this study provides a framework in the field of behavioral nutrition for applying machine learning with a focus on individual predictions. This is necessary on the road toward personalized nutrition and provides great potential for handling complex data with multiple variables.This trial was registered at clinicaltrials.gov as NCT03986619.

Is time-restricted eating a robust eating regimen during periods of disruptions in daily life? A qualitative study of perspectives of people with overweight during COVID-19.

BACKGROUND: Time-restricted eating (TRE) has been suggested as a feasible dietary strategy in individuals with overweight. Disruptions in daily life e.g., severe illness can affect engagement in lifestyle interventions to obtain healthier body weight. This study examined if and how the engagement with TRE among people with overweight was affected by the Danish COVID-19 lockdowns as an example of disruptions in daily life. METHODS: Fifteen participants with overweight enrolled in a TRE intervention, i.e. restricting all eating and drinking except water to the same daily ten-hour window, were interviewed about their experiences and engagement with TRE during COVID-19 lockdowns. Interviews were semi-structured and conducted by phone or face-to-face with safe social distancing. Data analysis was grounded in a reflexive thematic analysis approach. RESULTS: Daily life rhythms were disrupted by lockdowns by preventing participants from performing ordinary daily activities such as going to work, socialising, eating out or exercising. For some, this challenged their TRE engagement, while most were able to undertake the TRE eating window but reported increased snacking and consumption of take-away food within their eating window. For all, exercise habits became unhealthier. The negative impact on TRE engagement primarily occurred during daytime, as social distancing made it easier to engage with TRE during evenings. CONCLUSIONS: This study showed that even people highly motivated to obtain healthier lifestyles practices struggled to maintain engagement with healthy behaviours, whereas sticking to the TRE window was manageable during COVID-19. TRE as a weight loss strategy was challenged which calls for more attention to supporting people in daily life to obtain healthier practices, also in case of periods of other disruptions such as divorce, serious illness etc.

What happens after a weight loss intervention? A qualitative study of drivers and challenges of maintaining time-restricted eating among people with overweight at high risk of type 2 diabetes.

Time-restricted eating (TRE)1 has been conceptualised as a strategy for achieving weight loss and improving metabolic health, but limited knowledge exists about how people can maintain TRE in daily life. This study examined how TRE was maintainable in daily life after a three-month intervention (the RESET study) in which participants were encouraged to consume all food and beverages except water within a 10-h daily window. Specifically, we examined TRE maintenance patterns across participants, including drivers and challenges for maintenance success. A qualitative longitudinal study was conducted, and twenty participants with overweight at high risk of type 2 diabetes were interviewed using a semi-structured interview guide at the end of the intervention and after a three-month follow-up period. Data were analysed longitudinally in two steps inspired by a pattern-oriented longitudinal analysis approach. Seven participants maintained a strict 10-h window, ten maintained an adjusted TRE regimen (e.g., taking days off), and three did not attempt maintenance. Maintenance drivers included consistent daily rhythms and regular meal patterns, subjective experiences (e.g., feeling healthier), making flexible adjustments to the TRE regimen, family support and avoiding feelings of guilt. Maintenance challenges included social evening events, inconsistent daily rhythms and eating patterns, preoccupation with losing weight, lack of family support and self-blame. TRE was manageable for most participants; however, personalised support for adjusting TRE to daily life is needed to ensure long-term maintenance. Future studies should explore the effectiveness of a personalised TRE concept to determine the usefulness of TRE in real-life settings.

Watching, keeping and squeezing time to lose weight: Implications of time-restricted eating in daily life.

Time-restricted eating (TRE) is a novel intervention that allows eating and drinking within a certain time window and has shown positive effects on body weight in few studies. Weight loss strategies that easily can be integrated into daily life are needed, but knowledge about how TRE affects daily life is lacking. This study examined how individuals having overweight or obesity at high risk of type 2 diabetes performed TRE in daily life, with a focus on how the timing of eating changed the organisation and rhythms of daily activities. Semi-structured interviews were conducted with participants enrolled in a randomised controlled trial studying the effect of a 12-week TRE intervention focusing on a self-selected daily 10-h window between 6 AM and 8 PM. Seventeen participants from the intervention group were interviewed at baseline and end of intervention, and data were analysed using a thematic analysis approach. Participants found TRE simple and appealing due to the unrestricted dietary intake. In general, participants did not change their food preferences and continued to eat three main daily meals. However, participants had to increase their awareness of the time of day, reshuffle ordinary daily activities and plan their intake more carefully. Two participants reported fully adherence every day, whereas all other participants reported one to several episodes of intake outside their window during the 12 weeks. Social evening activities and collective rhythms were largest barriers. Our findings suggest that TRE interventions would benefit from a broader perspective on daily life and an expanded view on families and friends as joint units of intervention. TRE interventions should consider individuals' daily rhythms and help them develop practical solutions to integrating new eating practices.

Structured exercise alters the gut microbiota in humans with overweight and obesity-A randomized controlled trial.

OBJECTIVES: Studies suggest that exercise affects the composition and function of the human gut microbiota, yet this has not been investigated in a randomized controlled trial. The primary aim of this study was to assess if exercise alters the diversity, composition and functional potential of the gut microbiota in free-living humans. A secondary aim was to test whether alpha diversity was associated with phenotypical outcomes. METHODS: Eighty eight participants with overweight or obesity completed a 6-month randomized controlled trial with 4 arms; habitual living (CON), active commuting by bike (BIKE) and leisure-time exercise of moderate (MOD) or vigorous intensity (VIG). Faecal samples for 16 s rRNA gene amplicon sequencing were collected prior to randomization and again after 3 and 6 months, with simultaneous registration of phenotypical outcomes and diet. RESULTS: Shannon's diversity index increased by 5% in VIG (CI95 1-9%, P = 0.012) at 3 months compared with CON. No associations were observed between alpha diversity and phenotypical outcomes. Beta diversity changed in all exercise groups compared with CON, particularly the participants in VIG showed decreased heterogeneity. No genera changed significantly. The inferred functional potential of the microbiota in the exercise groups was increased, primarily at 3 months and in MOD. CONCLUSION: Structured exercise induced subtle changes to the human gut microbiota. Cardiorespiratory fitness and fat mass were not associated with alpha diversity.

Dietary habits, metabolic health and vitamin D status in Greenlandic children.

OBJECTIVE: To compare the dietary habits of children living in northern villages and in the capital of Greenland, given the reported transition from traditional to westernised diet in adults over recent decades, and to explore the association between consumption of marine mammals and fish (MMF) and the children's metabolic profile and vitamin D status. DESIGN: Children answered an FFQ encompassing sixty-four individual food types pooled into six food categories. Their pubertal stage, body fat, fitness level, metabolic profile (non-HDL-cholesterol, glycated Hb, insulin, glucose, high-sensitivity C-reactive protein) as well as serum 25-hydroxyvitamin D (25(OH)D) concentration were evaluated. SETTING: Siorapaluk and Qaanaaq (north of Greenland) and Nuuk (west). PARTICIPANTS: Children aged 6-18 years (n 177). RESULTS: MMF were most frequently eaten by children from Siorapaluk (mean (sd): 73·4 (14·1) times/month), followed by children from Qaanaaq (37·0 (25·0) times/month), and least often eaten by children from Nuuk (23·7 (24·6) times/month; P < 0·001). Children from Qaanaaq consumed 'junk food' more frequently (P < 0·001) and fruits and vegetables less frequently (P < 0·01) than children from Nuuk. MMF consumption was positively associated with serum 25(OH)D concentration (P < 0·05), but the overall prevalence of vitamin D deficiency was high (18 %). No association was found between MMF consumption and metabolic parameters. CONCLUSIONS: The dietary transition and influence of western diets have spread to the north of Greenland and only the most remote place consumed a traditional diet highly based on MMF. We found no strong associations of MMF consumption with metabolic health, but a positive association with vitamin D status.

PPARG Pro12Ala Ala carriers exhibit greater improvements in peripheral insulin sensitivity in response to 12 weeks of aerobic exercise training.

The Ala allele of PPARG Pro12Ala ( rs1801282 ) is associated with greater improvements to the glucose metabolism in exercise studies, but whether this extends to peripheral insulin sensitivity is unknown. Our objective was to investigate the effect of PPARG Pro12Ala on exercise-induced changes in peripheral insulin sensitivity. A total of 124 (91 Pro homozygotes and 33 Ala carriers) previously physically inactive healthy young men and women with overweight or class 1 obesity who completed a 12 wk aerobic exercise intervention were included in the analysis. All participants underwent a hyperinsulinemic euglycemic clamp before and after the 12 wk intervention. The prescribed exercise frequency was 5-7 days/wk, and the exercise energy expenditure was 2,100 4,200 kcal/wk for men and 1,600 kcal/wk for women. Insulin sensitivity improved significantly in both genotype groups. However, Ala carriers had a 1.13-fold (95% confidence interval 1.01; 1.26, P = 0.032) greater improvement in insulin sensitivity from baseline compared with Pro homozygotes. Our data support that PPARG Pro12Ala modifies the effect of aerobic exercise on peripheral insulin sensitivity.

How does 6 months of active bike commuting or leisure-time exercise affect insulin sensitivity, cardiorespiratory fitness and intra-abdominal fat? A randomised controlled trial in individuals with overweight and obesity.

OBJECTIVES: To evaluate effects of active bike commuting or leisure-time exercise of two intensities on peripheral insulin sensitivity (primary outcome), cardiorespiratory fitness and intra-abdominal adipose tissue mass (secondary outcomes). METHODS: 188 physically inactive, healthy women and men (20-45 years) with overweight or class 1 obesity were recruited. In the 6-month trial, 130 participants were randomised to either: no intervention (CON), active commuting (BIKE) or leisure-time exercise of moderate (MOD, 50% VO2peak) or vigorous (VIG, 70% VO2peak) intensity. 100 completed follow-up testing. Exercise prescription was 5 days/week with a weekly exercise energy expenditure of 1600 kcal for women and 2100 kcal for men. Testing was performed at baseline, 3 months and 6 months. RESULTS: Peripheral insulin sensitivity (ml/min/pmol insulin/L) increased (improved) by 24% (95% CI 6% to 46%, p=0.01) in VIG compared with CON at 3 months. Peripheral insulin sensitivity increased (improved) by 20% in BIKE (95% CI 1% to 43%, p=0.04) and 26% in VIG (95% CI 7% to 47%, p<0.01) compared with CON at 6 months. Cardiorespiratory fitness increased in all exercise groups compared with CON at 6 months; but the increase was higher in those that undertook vigorous exercise than those who did moderate exercise. Intra-abdominal adipose tissue mass diminished across all exercise groups in comparison to CON at 6 months. CONCLUSIONS: Active bike commuting improved cardiometabolic health; as did leisure-time exercise. Leisure-time exercise of vigorous intensity conferred more rapid effects on peripheral insulin sensitivity as well as additional effects on cardiorespiratory fitness than did moderate intensity exercise. TRIAL REGISTRATION: NCT01962259.

Effects of Plant-Based Diets on Markers of Insulin Sensitivity: A Systematic Review and Meta-Analysis of Randomised Controlled Trials.

The aim of this systematic review and meta-analysis was to examine the effects of plant-based diets on markers of insulin sensitivity in people with overweight/obesity, prediabetes, or type 2 diabetes (T2D). A systematic literature search in MEDLINE, Embase, CINAHL, and CENTRAL was conducted, and randomised controlled trials (RCTs) investigating the effect of plant-based diets (vegan, ovo-vegetarian, lacto-vegetarian, and lacto-ovo-vegetarian) for ≥14 d on markers of insulin sensitivity in adults (≥18 years) with BMI ≥ 25 kg/m2, prediabetes, or T2D were eligible. We identified eight RCTs, including 716 participants. In comparison with control diets, plant-based diets improved Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) (-0.97, 95% confidence interval (CI) (-1.67, -0.27), p = 0.007) and fasting insulin (-4.13 µU/mL, 95% CI (-7.22, -1.04), p = 0.009) in people with overweight/obesity. In people with prediabetes, one study compared vegan and vegetarian diets and found no difference in HOMA-IR, or fasting insulin. One study of people with T2D reported no difference in immunoreactive insulin and metabolic glucose clearance compared with a conventional diabetes diet. In conclusion, adhering to plant-based diets for ≥14 d improved HOMA-IR and fasting insulin in people with overweight/obesity. Long-term RCTs are needed to determine whether plant-based diets can result in prolonged improvements in insulin sensitivity in people at risk of or with T2D.

Effects of 3 months of 10-h per-day time-restricted eating and 3 months of follow-up on bodyweight and cardiometabolic health in Danish individuals at high risk of type 2 diabetes: the RESET single-centre, parallel, superiority, open-label, randomised controlled trial.

BACKGROUND: Time-restricted eating (TRE) has been suggested to be a simple, feasible, and effective dietary strategy for individuals with overweight or obesity. We aimed to investigate the effects of 3 months of 10-h per-day TRE and 3 months of follow-up on bodyweight and cardiometabolic risk factors in individuals at high risk of type 2 diabetes. METHODS: This was a single-centre, parallel, superiority, open-label randomised controlled clinical trial conducted at Steno Diabetes Center Copenhagen (Denmark). The inclusion criteria were age 30-70 years with either overweight (ie, BMI ≥25 kg/m2) and concomitant prediabetes (ie, glycated haemoglobin [HbA1c] 39-47 mmol/mol) or obesity (ie, BMI ≥30 kg/m2) with or without prediabetes and a habitual self-reported eating window (eating and drinking [except for water]) of 12 h per day or more every day and of 14 h per day or more at least 1 day per week. Individuals were randomly assigned 1:1 to 3 months of habitual living (hereafter referred to as the control group) or TRE, which was a self-selected 10-h per-day eating window placed between 0600 h and 2000 h. Randomisation was done in blocks varying in size and was open for participants and research staff, but outcome assessors were masked during statistical analyses. The randomisation list was generated by an external statistician. The primary outcome was change in bodyweight, assessed after 3 months (12 weeks) of the intervention and after 3 months (13 weeks) of follow-up. Adverse events were reported and registered at study visits or if participants contacted study staff to report events between visits. This trial is registered on ClinicalTrials.gov (NCT03854656). FINDINGS: Between March 12, 2019, and March 2, 2022, 100 participants (66 [66%] were female and 34 [34%] were male; median age 59 years [IQR 52-65]) were enrolled and randomly assigned (50 to each group). Of those 100, 46 (92%) in the TRE group and 46 (92%) in the control group completed the intervention period. After 3 months of the intervention, there was no difference in bodyweight between the TRE group and the control group (-0·8 kg, 95% CI -1·7 to 0·2; p=0·099). Being in the TRE group was not associated with a lower bodyweight compared with the control group after subsequent 3-month follow-up (-0·2 kg, -1·6 to 1·2). In the per-protocol analysis, participants who completed the intervention in the TRE group lost 1·0 kg (-1·9 to -0·0; p=0·040) bodyweight compared with the control group after 3 months of intervention, which was not maintained after the 3-month follow-up period (-0·4 kg, -1·8 to 1·0). During the trial and follow-up period, one participant in the TRE group reported a severe adverse event: development of a subcutaneous nodule and pain when the arm was in use. This side-effect was evaluated to be related to the trial procedures. INTERPRETATION: 3 months of 10-h per-day TRE did not lead to clinically relevant effects on bodyweight in middle-aged to older individuals at high risk of type 2 diabetes. FUNDING: Novo Nordisk Foundation, Aalborg University, Helsefonden, and Innovation Fund Denmark.

Feasibility of time-restricted eating in individuals with overweight, obesity, prediabetes, or type 2 diabetes: A systematic scoping review.

OBJECTIVE: This systematic scoping review aimed to map and synthesize research on feasibility of time-restricted eating (TRE) in individuals with overweight, obesity, prediabetes, or type 2 diabetes, including recruitment rate, retention rate, safety, adherence, and participants' attitudes, experiences, and perspectives. METHODS: The authors searched MEDLINE, Embase, and Cumulative Index to Nursing and Allied Health Literature from inception to November 22, 2022, supplemented by backward and forward citation search. RESULTS: From 4219 identified records, 28 studies were included. In general, recruitment was easy and median retention rate was 95% among studies with <12 weeks duration and 89% among studies ≥12 weeks. Median (range) adherence to the target eating window for studies <12 and ≥12 weeks was 89% (75%-98%) and 81% (47%-93%), respectively. Variation in adherence among participants and studies was considerable, indicating that following TRE was difficult for some people and that intervention conditions influenced adherence. These findings were supported by qualitative data synthetized from seven studies, and determinants of adherence included calorie-free beverages outside the eating window, provision of support, and influence on the eating window. No serious adverse events were reported. CONCLUSIONS: TRE is implementable, acceptable, and safe in populations with overweight, obesity, prediabetes, or type 2 diabetes, but it should be accompanied by support and options for individual adjustments.

Designing a Co-created Intervention to Promote Motivation and Maintenance of Time-Restricted Eating in Individuals With Overweight and Type 2 Diabetes.

OBJECTIVE: To design an appealing time-restricted eating (TRE) intervention by exploring behavioral and social mechanisms to improve TRE adoption and maintenance among people with type 2 diabetes (T2D) and overweight. Time-restricted eating is an intermittent fasting regimen suggested to improve glycemic control and body weight. METHODS: Intervention development combined coherence theory and empirical data (workshops and semistructured interviews with the target group, their relatives, and health care professionals [HCPs]). Abductive analysis was applied. RESULTS: The analysis suggested designing the TRE intervention in 2 phases: a short period with strict TRE, followed by a longer period focusing on adapting TRE to individual needs with support from HCPs, relatives, and peers. To reinforce TRE motivation and maintenance, HCPs should adopt a whole-person approach that focuses on participants' previous experiences. CONCLUSIONS AND IMPLICATIONS: Important intervention elements to promote TRE adoption and maintenance are suggested to include a 2-phase design and support from professionals, family, and peers.

Is Time-Restricted Eating Safe in the Treatment of Type 2 Diabetes?-A Review of Intervention Studies.

Time-restricted eating (TRE) has been shown to improve body weight and glucose metabolism in people at high risk of type 2 diabetes. However, the safety of TRE in the treatment of type 2 diabetes is unclear. We investigated the safety of TRE interventions in people with type 2 diabetes by identifying published and ongoing studies. Moreover, we identified the commonly used antidiabetic drugs and discussed the safety of TRE in people with type 2 diabetes considering the use of these drugs. In addition, we addressed the research needed before TRE can be recommended in the treatment of type 2 diabetes. A literature search was conducted to identify published (MEDLINE PubMed) and ongoing studies (ClinicalTrials.gov) on TRE in people with type 2 diabetes. To assess the usage of antidiabetic drugs and to discuss pharmacodynamics and pharmacokinetics in a TRE context, the most used antidiabetic drugs were identified and analysed. Statistics regarding sale of pharmaceuticals were obtained from MEDSTAT.DK which are based on data from the national Register of Medicinal Product Statistics, and from published studies on medication use in different countries. Four published studies investigating TRE in people with type 2 diabetes were identified as well as 14 ongoing studies. The completed studies suggested that TRE is safe among people with type 2 diabetes. Common antidiabetic drugs between 2010 and 2019 were metformin, insulin, dipeptidyl peptidase-4 inhibitors, glucagon-like peptide-1 receptor agonists, sulfonylureas, and sodium-glucose cotransporter-2 inhibitors. Existing studies suggest that TRE is not associated with major safety issues in people with type 2 diabetes as long as medication is monitored and adjusted. However, because of low generalisability of the few studies available, more studies are needed to make concrete recommendations regarding efficacy and safety of TRE in people with type 2 diabetes.

Effects of vegan diets on cardiometabolic health: A systematic review and meta-analysis of randomized controlled trials.

In parallel with an increased focus on climate changes and carbon footprint, the interest in plant-based diets and its potential health effects have increased over the past decade. The objective of this systematic review and meta-analysis was to examine the effect of vegan diets (≥12 weeks) on cardiometabolic risk factors in people with overweight or type 2 diabetes. We identified 11 trials (796 participants). In comparison with control diets, vegan diets reduced body weight (-4.1 kg, 95% confidence interval (CI) -5.9 to -2.4, p < 0.001), body mass index (BMI) (-1.38 kg/m2 , 95% CI -1.96 to -0.80, p < 0.001), glycated hemoglobin (HbA1c ) (-0.18% points, 95% CI -0.29 to -0.07, p = 0.002), total cholesterol (-0.30 mmol/L, 95% CI -0.52 to -0.08, p = 0.007), and low-density lipoprotein cholesterol (-0.24 mmol/L, 95% CI -0.40 to -0.07, p = 0.005). We identified no effect on blood pressure, high-density lipoprotein cholesterol, and triglycerides. We found that adhering to vegan diets for at least 12 weeks may be effective in individuals with overweight or type 2 diabetes to induce a meaningful decrease in body weight and improve glycemia. Some of this effect may be contributed to differences in the macronutrient composition and energy intake in the vegan versus control diets. Therefore, more research is needed regarding vegan diets and cardiometabolic health.

Food Reward after a Traditional Inuit or a Westernised Diet in an Inuit Population in Greenland.

The food availability and dietary behaviours in Greenland have changed with increasing Westernisation. Food reward is an important driver of food choice and intake, which has not previously been explored in the Arctic population. The aim of this study was to explore differences in food reward after a four-week intervention period with a traditional Inuit diet (TID) or Westernised diet (WD) in Inuit populations in Northern and Western Greenland. This cross-sectional analysis included 44 adults (n = 20 after TID and n = 24 after WD). We assessed the food reward components, explicit liking and implicit wanting, using the Leeds Food Preference Questionnaire under standardised conditions 60 min after drinking a glucose drink as part of an oral glucose tolerance test after four weeks following a TID or WD. The food intake was assessed using food frequency questionnaires. The intervention groups differed only in implicit wanting for high-fat sweet foods, with higher implicit wanting among the participants following TID compared to WD. Both groups had lower explicit liking and implicit wanting for sweet relative to savoury foods and for high-fat relative to low-fat foods. This exploratory study can guide future studies in Inuit populations to include measures of food reward to better understand food intake in the Arctic.

Late-evening food intake is highly prevalent among individuals with type 2 diabetes.

Late-evening food intake is associated with cardiometabolic risk. We assessed the prevalence of late-evening and night-time eating in individuals with type 2 diabetes and its association with BMI and HbA1c. We hypothesized food intake during late evening and night-time to be prevalent among individuals with type 2 diabetes and to be associated with higher BMI and higher HbA1c. This cross-sectional analysis includes 348 adults with type 2 diabetes from an outpatient diabetes clinic in Denmark. Frequency of late-evening and night-time eating was assessed from a food frequency questionnaire and clinical data were obtained from electronic medical records. Participants were divided into those reporting to eat frequently (≥3 times/week) in the evening after dinner and/or during night-time (late-eaters) and those who did not (reference group) and BMI and HbA1c levels were compared between groups with and without adjustment for diabetes duration and antidiabetic medication. 42% of the study population reported to eat frequently (≥3 times/week) in the late evening and 8% reported to do so during the night. Most late-eaters reported to eat breakfast regularly, suggesting a long eating window and short fasting period in this group. BMI and HbA1c did not differ between late-eaters and the reference group. Eating late in the evening or during the night was prevalent among individuals with type 2 diabetes across BMI and HbA1c levels. Whether restriction of food intake during evening and night-time can induce weight loss and improve glycemic control in individuals with type 2 diabetes needs testing in randomized controlled trials.

Associations between Postprandial Gut Hormones and Markers of Bone Remodeling.

Gut-derived hormones have been suggested to play a role in bone homeostasis following food intake, although the associations are highly complex and not fully understood. In a randomized, two-day cross-over study on 14 healthy individuals, we performed postprandial time-course studies to examine the associations of the bone remodeling markers carboxyl-terminal collagen type I crosslinks (CTX) and procollagen type 1 N-terminal propeptide (P1NP) with the gut hormones glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide 1 (GLP-1), and peptide YY (PYY) using two different meal types-a standardized mixed meal (498 kcal) or a granola bar (260 kcal). Plasma concentrations of total GIP, total GLP-1, total PYY, CTX, and P1NP were measured up to 240 min after meal intake, and the incremental area under the curve (iAUC) for each marker was calculated. The iAUC of CTX and P1NP were used to assess associations with the iAUC of GIP, GLP-1, and PYY in linear mixed effect models adjusted for meal type. CTX was positively associated with GIP and GLP-1, and it was inversely associated with PYY (all p < 0.001). No associations of P1NP with GIP or GLP-1 and PYY were found. In conclusion, the postprandial responses of the gut hormones GIP, GLP-1, and PYY are associated with the bone resorption marker CTX, supporting a link between gut hormones and bone homeostasis following food intake.

Effect of exercise training on skeletal muscle protein expression in relation to insulin sensitivity: Per-protocol analysis of a randomized controlled trial (GO-ACTIWE).

Exercise training improves peripheral insulin sensitivity and leads to molecular adaptations in the skeletal muscle. We investigated changes in the expression of key muscle proteins in the glucose metabolic pathway following active commuting by bike or leisure-time exercise at two different intensities. In addition, potential associations between insulin sensitivity and muscle protein expression were examined. This per-protocol analysis included 72 out of 130 physically inactive, healthy women and men (20-45 years) with overweight/obesity (BMI: 25-35 kg/m2 ) who completed 6 months of no intervention (CON, n = 12), active commuting by bike (BIKE, n = 14), or leisure-time exercise of moderate (MOD, n = 28) or vigorous (VIG, n = 18) intensity. Exercise was prescribed 5 days/week with a weekly exercise energy expenditure of 1,600 kcal for women and 2,100 kcal for men. Insulin sensitivity was determined by a hyperinsulinemic euglycemic clamp and skeletal muscle biopsies were obtained from m. vastus lateralis and analyzed for protein expression at baseline and after 3 and 6 months of intervention. We found an increased expression of pyruvate dehydrogenase (PDH) in the exercise groups compared with the control group following 6 months of training. No differential effects were observed on the protein expression following moderate versus vigorous intensity exercise. In addition, we found a positive association between insulin sensitivity and the expression of glucose transporter type 4 as well as PDH. The positive association and the increase in expression of PDH after exercise training points toward a role for PDH in the training-induced enhancement of insulin sensitivity.