The effects of inulin-type fructans on cardiovascular disease risk factors: systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Inulin-type fructans (ITF) are the leading prebiotics in the market. Available evidence provides conflicting results regarding the beneficial effects of ITF on cardiovascular disease risk factors. OBJECTIVES: This study aimed to evaluate the effects of ITF supplementation on cardiovascular disease risk factors in adults. METHODS: We searched MEDLINE, EMBASE, Emcare, AMED, CINAHL, and the Cochrane Library databases from inception through May 15, 2022. Eligible randomized controlled trials (RCTs) administered ITF or placebo (for example, control, foods, diets) to adults for ≥2 weeks and reported one or more of the following: low, very-low, or high-density lipoprotein cholesterol (LDL-C, VLDL-C, HDL-C); total cholesterol; apolipoprotein A1 or B; triglycerides; fasting blood glucose; body mass index; body weight; waist circumference; waist-to-hip ratio; systolic or diastolic blood pressure; or hemoglobin A1c. Two reviewers independently and in duplicate screened studies, extracted data, and assessed risk of bias. We pooled data using random-effects model, and assessed the certainty of evidence (CoE) using the Grading of Recommendations, Assessment, Development and Evaluation approach. RESULTS: We identified 1767 studies and included 55 RCTs with 2518 participants in meta-analyses. The pooled estimate showed that ITF supplementation reduced LDL-C [mean difference (MD) -0.14 mmol/L, 95% confidence interval (95% CI: -0.24, -0.05), 38 RCTs, 1879 participants, very low CoE], triglycerides (MD -0.06 mmol/L, 95% CI: -0.12, -0.01, 40 RCTs, 1732 participants, low CoE), and body weight (MD -0.97 kg, 95% CI: -1.28, -0.66, 36 RCTs, 1672 participants, low CoE) but little to no significant effect on other cardiovascular disease risk factors. The effects were larger when study duration was ≥6 weeks and in pre-obese and obese participants. CONCLUSION: ITF may reduce low-density lipoprotein, triglycerides, and body weight. However, due to low to very low CoE, further well-designed and executed trials are needed to confirm these effects. PROSPERO REGISTRATION NUMBER: CRD42019136745.

Plant-Based Milk Consumption and Growth in Children 1-10 Years of Age.

BACKGROUND: The effects of plant-based milk consumption on the growth of children are unclear. OBJECTIVES: We aimed to evaluate the relationship between plant-based milk consumption and BMI in childhood. Secondary objectives were to examine the association with height and whether these relationships are mediated by dairy milk intake and modified by age or the type of plant-based milk consumed. METHODS: A prospective cohort study was conducted in healthy children aged 1-10 y through the TARGet Kids! primary care research network in Toronto, Canada. Linear mixed-effect modeling and logistic generalized estimating equations were used to evaluate the association between plant-based milk consumption (number of 250 mL cups/d) and BMI. A mediation analysis was conducted to examine whether dairy milk intake mediated these relationships. Effect modification by age and type of plant-based milk was explored. RESULTS: Among 7195 children (mean age: 3.1 y; 52.3% male), higher plant-based milk consumption was associated with lower BMI (P = 0.0002) and height (P = 0.005). No association was found with BMI categories. Lower dairy milk intake partially mediated these relationships. A child aged 5 y who consumed 3 cups of plant-based milk compared with 3 cups of dairy milk had a lower weight of 0.5 kg and lower height of 0.8 cm. Associations did not change over time and were similar for children who consumed soy milk compared with other plant-based milks. CONCLUSIONS: Plant-based milk consumption was associated with lower BMI and height, but both were within the normal range on average. Future longitudinal studies are needed to determine whether these associations persist over time.

The Environmental Sustainability of Plant-Based Dietary Patterns: A Scoping Review.

BACKGROUND: A large part of the existential threat associated with climate change is the result of current human feeding patterns. Over the last decade, research evaluating the diet-related environmental impacts of plant-based diets has emerged, and a synthesis of the available data is now due. OBJECTIVES: The objectives of the study were as follows: 1) to compile and summarize the literature on diet-related environmental impacts of plant-based dietary patterns; 2) to assess the nature of the data on impacts of plant-based dietary patterns on both environmental parameters and health (e.g., if land use is reduced for a particular diet, is cancer risk also reduced?); and 3) to determine where sufficient data exist for meta-analyses, in addition to identifying gaps within the literature. METHODS: Global peer-reviewed studies on the environmental impacts of plant-based diets were searched in Ovid MEDLINE, EMBASE, and Web of Science. After removing duplicates, the screening identified 1553 records. After 2 stages of independent review by 2 reviewers, 65 records met the inclusion criteria and were eligible to be used in synthesis. RESULTS: Evidence suggests that plant-based diets may offer lower greenhouse gas emissions (GHGEs), land use, and biodiversity loss than offered by standard diets; however, the impact on water and energy use may depend on the types of plant-based foods consumed. Further, the studies were consistent in demonstrating that plant-based dietary patterns that reduce diet-related mortality also promote environmental sustainability. CONCLUSIONS: Overall, there was agreement across the studies regarding the impact of plant-based dietary patterns on GHGE, land used, and biodiversity loss despite varied plant-based diets assessed.

Important food sources of fructose-containing sugars and adiposity: A systematic review and meta-analysis of controlled feeding trials.

BACKGROUND: Sugar-sweetened beverages (SSBs) providing excess energy increase adiposity. The effect of other food sources of sugars at different energy control levels is unclear. OBJECTIVES: To determine the effect of food sources of fructose-containing sugars by energy control on adiposity. METHODS: In this systematic review and meta-analysis, MEDLINE, Embase, and Cochrane Library were searched through April 2022 for controlled trials ≥2 wk. We prespecified 4 trial designs by energy control: substitution (energy-matched replacement of sugars), addition (energy from sugars added), subtraction (energy from sugars subtracted), and ad libitum (energy from sugars freely replaced). Independent authors extracted data. The primary outcome was body weight. Secondary outcomes included other adiposity measures. Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used to assess the certainty of evidence. RESULTS: We included 169 trials (255 trial comparisons, n = 10,357) assessing 14 food sources at 4 energy control levels over a median 12 wk. Total fructose-containing sugars increased body weight (MD: 0.28 kg; 95% CI: 0.06, 0.50 kg; PMD = 0.011) in addition trials and decreased body weight (MD: -0.96 kg; 95% CI: -1.78, -0.14 kg; PMD = 0.022) in subtraction trials with no effect in substitution or ad libitum trials. There was interaction/influence by food sources on body weight: substitution trials [fruits decreased; added nutritive sweeteners and mixed sources (with SSBs) increased]; addition trials [dried fruits, honey, fruits (≤10%E), and 100% fruit juice (≤10%E) decreased; SSBs, fruit drink, and mixed sources (with SSBs) increased]; subtraction trials [removal of mixed sources (with SSBs) decreased]; and ad libitum trials [mixed sources (with/without SSBs) increased]. GRADE scores were generally moderate. Results were similar across secondary outcomes. CONCLUSIONS: Energy control and food sources mediate the effect of fructose-containing sugars on adiposity. The evidence provides a good indication that excess energy from sugars (particularly SSBs at high doses ≥20%E or 100 g/d) increase adiposity, whereas their removal decrease adiposity. Most other food sources had no effect, with some showing decreases (particularly fruits at lower doses ≤10%E or 50 g/d). This trial was registered at clinicaltrials.gov as NCT02558920 (https://clinicaltrials.gov/ct2/show/NCT02558920).

Low-carbohydrate vegan diets in diabetes for weight loss and sustainability: a randomized controlled trial.

BACKGROUND: Low-carbohydrate, high animal fat and protein diets have been promoted for weight loss and diabetes treatment. We therefore tested the effect of a low-carbohydrate vegan diet in diabetes as a potentially healthier and more ecologically sustainable low-carbohydrate option. OBJECTIVES: We sought to compare the effectiveness of a low-carbohydrate vegan diet with a moderate-carbohydrate vegetarian diet on weight loss and metabolic measures in diabetes. METHODS: One hundred and sixty-four male and female participants with type 2 diabetes were randomly assigned to advice on either a low-carbohydrate vegan diet, high in canola oil and plant proteins, or a vegetarian therapeutic diet, for 3 mo, with both diets recommended at 60% of calorie requirements. Body weight, fasting blood, blood pressure, and 7-d food records, to estimate potential greenhouse gas emissions, were obtained throughout the study with tests of cholesterol absorption undertaken at baseline and end of study on 50 participants. RESULTS: Both low-carbohydrate vegan and vegetarian diets similarly but markedly reduced body weight (-5.9 kg; 95% CI: -6.5, -5.28 kg; and -5.23 kg; 95% CI: -5.84, -4.62 kg), glycated hemoglobin (-0.99%; 95% CI: -1.07, -0.9%; and -0.88%; 95% CI: -0.97, -0.8%), systolic blood pressure (-4 mmHg; 95% CI: -7, -2 mmHg; and -6 mmHg; 95% CI: -8, -3 mmHg), and potential greenhouse gas emissions, but only for potential greenhouse gas emissions was there a significant treatment difference of -0.63 kgCO2/d (95% CI: -0.99, -0.27 kgCO2/d) favoring the low-carbohydrate vegan diet. CONCLUSIONS: Low-carbohydrate vegan and vegetarian diets reduced body weight, improved glycemic control and blood pressure, but the more plant-based diet had greater potential reduction in greenhouse gas emissions. TRIAL REGISTRATION NUMBER: clinicaltrials.gov identifier NCT02245399.

Different Food Sources of Fructose-Containing Sugars and Fasting Blood Uric Acid Levels: A Systematic Review and Meta-Analysis of Controlled Feeding Trials.

BACKGROUND: Although fructose as a source of excess calories increases uric acid, the effect of the food matrix is unclear. OBJECTIVES: To assess the effects of fructose-containing sugars by food source at different levels of energy control on uric acid, we conducted a systematic review and meta-analysis of controlled trials. METHODS: MEDLINE, Embase, and the Cochrane Library were searched (through 11 January 2021) for trials ≥ 7 days. We prespecified 4 trial designs by energy control: substitution (energy-matched replacement of sugars in diets); addition (excess energy from sugars added to diets); subtraction (energy from sugars subtracted from diets); and ad libitum (energy from sugars freely replaced in diets) designs. Independent reviewers (≥2) extracted data and assessed the risk of bias. Grading of Recommendations, Assessment, Development, and Evaluation was used to assess the certainty of evidence. RESULTS: We included 47 trials (85 comparisons; N = 2763) assessing 9 food sources [sugar-sweetened beverages (SSBs), sweetened dairy, fruit drinks, 100% fruit juice, fruit, dried fruit, sweets and desserts, added nutritive sweetener, and mixed sources] across 4 energy control levels in predominantly healthy, mixed-weight adults. Total fructose-containing sugars increased uric acid levels in substitution trials (mean difference, 0.16 mg/dL;  95% CI:  0.06-0.27 mg/dL;  P = 0.003), with no effect across the other energy control levels. There was evidence of an interaction by food source: SSBs and sweets and desserts increased uric acid levels in the substitution design, while SSBs increased and 100% fruit juice decreased uric acid levels in addition trials. The certainty of evidence was high for the increasing effect of SSBs in substitution and addition trials and the decreasing effect of 100% fruit juice in addition trials and was moderate to very low for all other comparisons. CONCLUSIONS: Food source more than energy control appears to mediate the effects of fructose-containing sugars on uric acid. The available evidence provides reliable indications that SSBs increase and 100% fruit juice decreases uric acid levels. More high-quality trials of different food sources are needed. This trial was registered at clinicaltrials.gov as NCT02716870.

Effect of vegetarian dietary patterns on cardiometabolic risk factors in diabetes: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND & AIMS: To update the European Association for the Study of Diabetes (EASD) clinical practice guidelines for nutrition therapy, we conducted a systematic review and meta-analysis of randomized controlled trials to summarize the evidence for the effect of vegetarian dietary patterns on glycemic control and other established cardiometabolic risk factors in individuals with diabetes. METHODS: We searched MEDLINE, EMBASE, and Cochrane databases through February 26, 2018 for randomized controlled trials ≥3 weeks assessing the effect of vegetarian dietary patterns in individuals with diabetes. The primary outcome was HbA1c. Secondary outcomes included other markers of glycemic control, blood lipids, body weight/adiposity, and blood pressure. Two independent reviewers extracted data and assessed risk of bias. Data were pooled by the generic inverse variance method and expressed as mean differences (MD) with 95% CIs. Heterogeneity was assessed (Cochran Q statistic) and quantified (I2 statistic). The overall certainty of the evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. RESULTS: Nine trials (n = 664 participants) met the eligibility criteria. Vegetarian dietary patterns significantly lowered HbA1c (MD = -0.29% [95% CI: -0.45, -0.12%]), fasting glucose (MD = -0.56 mmol/L [95% CI: -0.99, -0.13 mmol/L]), LDL-C (MD = -0.12 mmol/L [95% CI: -0.20, -0.04 mmol/L]), non-HDL-C (MD = -0.13 mmol/L [95% CI: -0.26, -0.01 mmol/L]), body weight (MD = -2.15 kg [95% CI: -2.95, -1.34 kg]), BMI (MD = -0.74 kg/m2 [95% CI: -1.09, -0.39 kg/m2]) and waist circumference (MD = -2.86 cm [95% CI: -3.76, -1.96 cm]). There was no significant effect on fasting insulin, HDL-C, triglycerides or blood pressure. The overall certainty of evidence was moderate but was low for fasting insulin, triglycerides and waist circumference. CONCLUSION: Vegetarian dietary patterns improve glycemic control, LDL-C, non-HDL-C, and body weight/adiposity in individuals with diabetes, supporting their inclusion for diabetes management. More research is needed to improve our confidence in the estimates. CLINICALTRIALS. GOV IDENTIFIER: NCT02600377.

Biomarkers of cardiometabolic health and nutritional status in individuals with positive celiac disease serology.

BACKGROUND: Celiac disease (CD) is an autoimmune disorder characterized by damage to the intestinal mucosa and nutrient malabsorption in severe cases. However, it remains unclear whether nutrient deficiencies and other adverse health effects are prevalent in individuals with positive CD serology identified through screening studies. OBJECTIVE: The objective was to determine whether biomarkers of cardiometabolic health and nutritional status differ between those with positive and negative CD serology identified in a screening study of Canadian adults. METHODS: Participants ( n=2832) were from the Toronto Nutrigenomics and Health Study and the Toronto Healthy Diet Study. Individuals were screened for CD-specific anti-tissue transglutaminase autoantibodies. Lipid profiles as well as concentrations of six carotenoids (α-carotene, ß-carotene, ß-cryptoxanthin, lutein, lycopene, and zeaxanthin), three tocopherols (α-tocopherol, δ-tocopherol, and γ-tocopherol), retinol, ascorbic acid, and 25-hydroxyvitamin D were cross-sectionally compared between those with positive and negative CD serology using general linear mixed models. RESULTS: Individuals with positive CD serology ( n=23) had significantly lower levels of HDL-cholesterol ( p=0.008) and apolipoprotein-AI ( p=0.02), a higher ratio of total cholesterol to HDL-cholesterol ( p=0.006), and a higher apolipoprotein-B/AI ratio ( p=0.03) than those with negative CD serology. Positive CD serology was also associated with significantly lower concentrations of retinol ( p=0.006) in fully adjusted models. Those with positive CD serology had lower serum 25-hydroxyvitamin D in unadjusted models ( p=0.01), but not in fully adjusted models ( p=0.08). CONCLUSIONS: Individuals with undiagnosed CD may have unfavorable lipid profiles and be at elevated risk for inadequacy of certain fat-soluble vitamins, but not widespread nutrient deficiencies.

Effects of dietary pulse consumption on body weight: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Obesity is a risk factor for developing several diseases, and although dietary pulses (nonoil seeds of legumes such as beans, lentils, chickpeas, and dry peas) are well positioned to aid in weight control, the effects of dietary pulses on weight loss are unclear. OBJECTIVE: We summarized and quantified the effects of dietary pulse consumption on body weight, waist circumference, and body fat by conducting a systematic review and meta-analysis of randomized controlled trials. DESIGN: We searched the databases MEDLINE, Embase, CINAHL, and the Cochrane Library through 11 May 2015 for randomized controlled trials of ≥3 wk of duration that compared the effects of diets containing whole dietary pulses with those of comparator diets without a dietary pulse intervention. Study quality was assessed by means of the Heyland Methodologic Quality Score, and risk of bias was assessed with the Cochrane Risk of Bias tool. Data were pooled with the use of generic inverse-variance random-effects models. RESULTS: Findings from 21 trials (n = 940 participants) were included in the meta-analysis. The pooled analysis showed an overall significant weight reduction of -0.34 kg (95% CI: -0.63, -0.04 kg; P = 0.03) in diets containing dietary pulses (median intake of 132 g/d or ∼1 serving/d) compared with diets without a dietary pulse intervention over a median duration of 6 wk. Significant weight loss was observed in matched negative-energy-balance (weight loss) diets (P = 0.02) and in neutral-energy-balance (weight-maintaining) diets (P = 0.03), and there was low evidence of between-study heterogeneity. Findings from 6 included trials also suggested that dietary pulse consumption may reduce body fat percentage. CONCLUSIONS: The inclusion of dietary pulses in a diet may be a beneficial weight-loss strategy because it leads to a modest weight-loss effect even when diets are not intended to be calorically restricted. Future studies are needed to determine the effects of dietary pulses on long-term weight-loss sustainability. This protocol was registered at clinicaltrials.gov as NCT01594567.

Sugar-sweetened beverage consumption and incident hypertension: a systematic review and meta-analysis of prospective cohorts.

BACKGROUND: The role of sugar-sweetened beverages (SSBs) that contain free or bound fructose in the pathogenesis of hypertension remains unclear. OBJECTIVE: We conducted a systematic review and meta-analysis of prospective cohort studies to quantify the association between fructose-containing SSBs and risk of hypertension. DESIGN: MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature, and the Cochrane registry were searched from conception through 11 November 2014. Two independent reviewers extracted data and assessed the quality of studies (with the use of the Newcastle-Ottawa Scale). Risk estimates of extreme quantiles of SSB intake (lowest compared with highest) for hypertension incidence were generated with the use of generic inverse-variance methods with random-effects models and expressed as risk ratios with 95% CIs. Heterogeneity was assessed with the Cochran Q statistic and quantified with the I(2) statistic. RESULTS: Six prospective cohort studies (n = 240,508) with 79,251 cases of hypertension observed over ≥3,197,528 person-years of follow-up were included. SSB consumption significantly increased the risk of developing hypertension by 12% (risk ratio: 1.12; 95% CI: 1.06, 1.17) with evidence of significant heterogeneity (I(2) = 62%, P = 0.02) when highest [≥1 serving (6.7, 8, or 12 oz)/d] and lowest (none) quantiles of intake were compared. With the use of a dose-response analysis, a significant 8.2% increase in risk of every additional SSB per day from none to ≥1 SSB/d (ß = 0.0027, P < 0.001) was identified. Limitations include unexplained heterogeneity and residual confounding. The results may also have been subject to collinearity effects from aspects of a Western dietary pattern. CONCLUSIONS: SSBs were associated with a modest risk of developing hypertension in 6 cohorts. There is a need for high-quality randomized trials to assess the role of SSBs in the development of hypertension and its complications. This study was registered at clinicaltrials.gov as NCT01608620.