Comparison of 5% versus 15% sucrose intakes as part of a eucaloric diet in overweight and obese subjects: effects on insulin sensitivity, glucose metabolism, vascular compliance, body composition and lipid profile. A randomised controlled trial

Fructose-containing food sources and blood pressure: A systematic review and meta-analysis of controlled feeding trials

Whether food source or energy mediates the effect of fructose-containing sugars on blood pressure (BP) is unclear. We conducted a systematic review and meta-analysis of the effect of different food sources of fructose-containing sugars at different levels of energy control on BP. We searched MEDLINE, Embase and the Cochrane Library through June 2021 for controlled trials ≥7-days. We prespecified 4 trial designs: substitution (energy matched substitution of sugars); addition (excess energy from sugars added); subtraction (excess energy from sugars subtracted); and ad libitum (energy from sugars freely replaced). Outcomes were systolic and diastolic BP. Independent reviewers extracted data. GRADE assessed the certainty of evidence. We included 93 reports (147 trial comparisons, N = 5,213) assessing 12 different food sources across 4 energy control levels in adults with and without hypertension or at risk for hypertension. Total fructose-containing sugars had no effect in substitution, subtraction, or ad libitum trials but decreased systolic and diastolic BP in addition trials (P<0.05). There was evidence of interaction/influence by food source: fruit and 100% fruit juice decreased and mixed sources (with sugar-sweetened beverages [SSBs]) increased BP in addition trials and the removal of SSBs (linear dose response gradient) and mixed sources (with SSBs) decreased BP in subtraction trials. The certainty of evidence was generally moderate. Food source and energy control appear to mediate the effect of fructose-containing sugars on BP. The evidence provides a good indication that fruit and 100% fruit juice at low doses (up to or less than the public health threshold of ~10% E) lead to small, but important reductions in BP, while the addition of excess energy of mixed sources (with SSBs) at high doses (up to 23%) leads to moderate increases and their removal or the removal of SSBs alone (up to ~20% E) leads to small, but important decreases in BP in adults with and without hypertension or at risk for hypertension. Trial registration: Clinicaltrials.gov: NCT02716870.

Total added sugar consumption is not significantly associated with risk for prediabetes among U.S. adults: National Health and Nutrition Examination Survey, 2013-2018

Prediabetes affects 38% of U.S. adults and is primarily linked to added sugars consumed from sugar-sweetened beverages. It is unclear if total dietary intake of added sugar also increases the risk for prediabetes. This study examined if total (g/day) and percent intakes of <10%, 10-15%, or >15% added sugar increase the odds for prediabetes in U.S. adults. A cross-sectional, secondary analysis using 2013-2018 NHANES data was conducted. This study included data from U.S. adults ≥ 20 years with normoglycemia (N = 2,154) and prediabetes (N = 3,152) with 1-2 days of dietary recall information. Prediabetes was defined as a hemoglobin A1c of 5.7%-6.4% or a fasting plasma glucose of 100-125 mg/dL. Survey-weighted logistic regression was used to estimate odds ratios of prediabetes based on usual intakes of added sugar (total and percent intakes) using the National Cancer Institute Method. Differences in prediabetes risk and total and percent intakes of added sugar were compared by race/ethnicity. The sample's total energy intake from added sugar was 13.9%. Total (unadjusted: OR: 1.01, 95% CI: .99-1.00, p = .26; adjusted: OR: 1.00, 95% CI: .99-1.00, p = .91) and percent intakes of added sugar (unadjusted [<10%: (ref); 10-15%: OR: .93, 95% CI: .77-1.12, p = .44; >15%: OR: 1.03, 95% CI: .82-1.28, p = .82] and adjusted [<10%: (ref); 10-15%: OR: .82, 95% CI: .65-1.04, p = .09; >15%: OR: .96, 95% CI: .74-1.24, p = .73]) were not significantly associated with an increased odds of prediabetes. Prediabetes risk did not differ by race/ethnicity for total (unadjusted model [p = .65]; adjusted model [p = .51]) or percent (unadjusted model [p = .21]; adjusted model [p = .11]) added sugar intakes. In adults ≥20 years with normoglycemia and prediabetes, total added sugar consumption did not significantly increase one's risk for prediabetes and risk estimates did not differ by race/ethnicity. Experimental studies should expand upon this work to confirm these findings.

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; P_MD = 0.011) in addition trials and decreased body weight (MD: -0.96 kg; 95% CI: -1.78, -0.14 kg; P_MD = 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).

Current WHO recommendation to reduce free sugar intake from all sources to below 10% of daily energy intake for supporting overall health is not well supported by available evidence

Sugar is widely consumed over the world. Although the mainstream view is that high added or free sugar consumption leads to obesity and related metabolic diseases, controversies exist. This narrative review aims to highlight important findings and identify major limitations and gaps in the current body of evidence in relation to the effect of high sugar intakes on health. Previous animal studies have shown that high sucrose or fructose consumption causes insulin resistance in the liver and skeletal muscle and consequent hyperglycemia, mainly because of fructose-induced de novo hepatic lipogenesis. However, evidence from human observational studies and clinical trials has been inconsistent, where most if not all studies linking high sugar intake to obesity focused on sugar-sweetened beverages (SSBs), and studies focusing on sugars from solid foods yielded null findings. In our opinion, the substantial limitations in the current body of evidence, such as short study durations, use of supraphysiological doses of sugar or fructose alone in animal studies, and a lack of direct comparisons of the effects of solid compared with liquid sugars on health outcomes, as well as the lack of appropriate controls, seriously curtail the translatability of the findings to real-world situations. It is quite possible that "high" sugar consumption at normal dietary doses (e.g., 25% daily energy intake) per se-that is, the unique effect of sugar, especially in the solid form-may indeed not pose a health risk for individuals apart from the potential to reduce the overall dietary nutrient density, although newer evidence suggests "low" sugar intake (<5% daily energy intake) is just as likely to be associated with nutrient dilution. We argue the current public health recommendations to encourage the reduction of both solid and liquid forms of free sugar intake (e.g., sugar reformulation programs) should be revised due to the overextrapolation of results from SSBs studies.

High versus low-added sugar consumption for the primary prevention of cardiovascular disease

BACKGROUND

High intake of added sugar have been suggested to impact the risk for cardiovascular disease (CVD). Knowledge on the subject can contribute to preventing CVD.

OBJECTIVES

To assess the effects of a high versus low-added sugar consumption for primary prevention of CVD in the general population.

SEARCH METHODS

We searched Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE, Embase, Conference Proceedings Citation Index-Science (CPCI-S) on 2 July 2021. We also conducted a search of ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP) Search Portal for ongoing or unpublished trials. The search was performed together with reference checking, citation searching and contact with study authors to identify additional studies. We imposed no restriction on language of publication or publication status.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), including cross-over trials, that compared different levels of added sugar intake. Exclusion criteria were: participants aged below 18 years; diabetes mellitus (type 1 and 2); and previous CVD. Primary outcomes were incident cardiovascular events (coronary, carotid, cerebral and peripheral arterial disease) and all-cause mortality. Secondary outcomes were changes in systolic and diastolic blood pressure, total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, fasting plasma glucose and adverse events (gastrointestinal symptoms and impaired dental health).

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 21 RCTs (1110 participants completing the interventions) examining the effects of different levels of added sugar intake with a mean duration of 14 weeks. The study participants were generally described as healthy and the mean age ranged from 22 to 57 years. No studies reported on cardiovascular events or all-cause mortality. There was minimal effect of low intake of added sugar on total cholesterol levels (MD 0.11, 95% CI 0.01 to 0.21; I² = 0%; 16 studies; 763 participants; low certainty of evidence) and triglycerides (MD 0.10, 95% CI 0.03 to 0.17; I² = 3%; 14 studies; 725 participants) but no evidence of effect on LDL-cholesterol and HDL-cholesterol. There was minimal effect on diastolic blood pressure (MD 1.52, 95% CI 0.67 to 2.37; I² = 0%; 13 studies; 873 participants) and on systolic blood pressure (MD 1.44, 95% 0.08 to 2.80; I² = 27%, 14 studies; 873 participants; low certainty of evidence), but no evidence of effect on fasting plasma glucose. Only one study reported on dental health, with no events. No other trials reported adverse events (impaired dental health or gastrointestinal symptoms). All results were judged as low-quality evidence according to GRADE. The risk of bias was generally unclear, five studies were classified at an overall low risk of bias (low risk in at least four domains, not including other bias).

AUTHORS' CONCLUSIONS

No trials investigating the effect of added sugar on cardiovascular events or all-cause mortality were identified in our searches. Evidence is uncertain whether low intake of added sugar has an effect on risk factors for CVD; the effect was small and the clinical relevance is, therefore, uncertain. Practical ways to achieve reductions in dietary added sugar includes following current dietary recommendations. Future trials should have longer follow-up time and report on all-cause mortality and cardiovascular events in order to clarify the effect of added sugar on these outcomes. Future trials should also aim for more direct interventions and preferably be more independent of industry funding.

Consuming Sucrose- or HFCS-sweetened Beverages Increases Hepatic Lipid and Decreases Insulin Sensitivity in Adults

CONTEXT

Studies in rodents and humans suggest that high-fructose corn syrup (HFCS)-sweetened diets promote greater metabolic dysfunction than sucrose-sweetened diets.

OBJECTIVE

To compare the effects of consuming sucrose-sweetened beverage (SB), HFCS-SB, or a control beverage sweetened with aspartame on metabolic outcomes in humans.

METHODS

A parallel, double-blinded, NIH-funded study. Experimental procedures were conducted during 3.5 days of inpatient residence with controlled feeding at a research clinic before (baseline) and after a 12-day outpatient intervention period. Seventy-five adults (18-40 years) were assigned to beverage groups matched for sex, body mass index (18-35 kg/m2), and fasting triglyceride, lipoprotein and insulin concentrations. The intervention was 3 servings/day of sucrose- or HFCS-SB providing 25% of energy requirement or aspartame-SB, consumed for 16 days. Main outcome measures were %hepatic lipid, Matsuda insulin sensitivity index (ISI), and Predicted M ISI.

RESULTS

Sucrose-SB increased %hepatic lipid (absolute change: 0.6 ± 0.2%) compared with aspartame-SB (-0.2 ± 0.2%, P < 0.05) and compared with baseline (P < 0.001). HFCS-SB increased %hepatic lipid compared with baseline (0.4 ± 0.2%, P < 0.05). Compared with aspartame-SB, Matsuda ISI decreased after consumption of HFCS- (P < 0.01) and sucrose-SB (P < 0.01), and Predicted M ISI decreased after consumption of HFCS-SB (P < 0.05). Sucrose- and HFCS-SB increased plasma concentrations of lipids, lipoproteins, and uric acid compared with aspartame-SB. No outcomes were differentially affected by sucrose- compared with HFCS-SB. Beverage group effects remained significant when analyses were adjusted for changes in body weight.

CONCLUSION

Consumption of both sucrose- and HFCS-SB induced detrimental changes in hepatic lipid, insulin sensitivity, and circulating lipids, lipoproteins and uric acid in 2 weeks.

A pilot feasibility study investigating the impact of increasing sucrose intakes on body composition and blood pressure

Epidemiological and intervention studies have reported negative health effects of sucrose intake, but many of these studies were not representative of typical dietary habits. In this pilot study, we aimed to test the effect of increasing sucrose intakes for 1 week on body composition and blood pressure and explore the feasibility of consuming high intakes of sucrose in addition to a habitual diet. In a randomised crossover design study, twelve healthy participants (50 % female, age 28⋅4 ± 10 years, BMI 25 ± 3 kg/m²), consumed either 40, 80 or 120 g sucrose in 500 ml water in addition to their habitual diet every day for 1 week, with a 1-week washout between treatment periods. Body composition (assessed using bioelectrical impedance) and blood pressure measurements were taken before and after each intervention phase. All participants reported no issues with consuming the sucrose dose for the intervention period. There was a significant increase in systolic blood pressure following 120 g sucrose intake (P = 0⋅006), however there was no significant changes to blood pressure, body weight, BMI, percentage protein, fat or water (P > 0⋅05) when comparing change from baseline values. There was also no effect of sucrose intakes on energy or macronutrient intakes during the intervention (P > 0⋅05). We show here that varying doses of sucrose over a 1-week period have no effect on body composition or blood pressure. The amounts of sucrose used were an acceptable addition to the habitual diet and demonstrate the feasibility of larger-scale studies of chronic sucrose supplementation.

Chronic Effects of a High Sucrose Diet on Murine Gastrointestinal Nutrient Sensor Gene and Protein Expression Levels and Lipid Metabolism

The gastrointestinal tract (GIT) plays a key role in regulating nutrient metabolism and appetite responses. This study aimed to identify changes in the GIT that are important in the development of diet related obesity and diabetes. GIT samples were obtained from C57BL/6J male mice chronically fed a control diet or a high sucrose diet (HSD) and analysed for changes in gene, protein and metabolite levels. In HSD mice, GIT expression levels of fat oxidation genes were reduced, and increased de novo lipogenesis was evident in ileum. Gene expression levels of the putative sugar sensor, slc5a4a and slc5a4b, and fat sensor, cd36, were downregulated in the small intestines of HSD mice. In HSD mice, there was also evidence of bacterial overgrowth and a lipopolysaccharide activated inflammatory pathway involving inducible nitric oxide synthase (iNOS). In Caco-2 cells, sucrose significantly increased the expression levels of the nos2, iNOS and nitric oxide (NO) gas levels. In conclusion, sucrose fed induced obesity/diabetes is associated with changes in GI macronutrient sensing, appetite regulation and nutrient metabolism and intestinal microflora. These may be important drivers, and thus therapeutic targets, of diet-related metabolic disease.

Dietary sugars and cardiometabolic risk factors: a network meta-analysis on isocaloric substitution interventions

BACKGROUND

There is controversy on the relevance of dietary sugar intake for cardiometabolic health.

OBJECTIVE

The aim of this network meta-analysis (NMA) was to assess how isocaloric substitutions of dietary sugar with other carbohydrates affect cardiometabolic risk factors, comparing different intervention studies.

METHODS

We included randomized controlled trials (RCTs) investigating the isocaloric effect of substituting dietary sugars (fructose, glucose, sucrose) with other sugars or starch on cardiometabolic risk markers, including LDL cholesterol, triacylglycerol (TG), fasting glucose (FG), glycated hemoglobin (HbA1c), insulin resistance (HOMA-IR), uric acid, C-reactive protein (CRP), alanine transaminase (ALT), aspartate transaminase (AST), and liver fat content. To identify the most beneficial intervention for each outcome, random-effects NMA was conducted by calculating pooled mean differences (MDs) with 95% CIs, and by ranking the surface under the cumulative ranking curves (SUCRAs). The certainty of evidence was evaluated using the Confidence In Network Meta-Analysis tool.

RESULTS

Thirty-eight RCTs, including 1383 participants, were identified. A reduction in LDL-cholesterol concentrations was shown for the exchange of sucrose with starch (MD: -0.23 mmol/L; 95% CI: -0.38, -0.07 mmol/L) or fructose with starch (MD: -0.22 mmol/L; 95% CI: -0.39, -0.05 mmol/L; SUCRAstarch: 98%). FG concentrations were also lower for the exchange of sucrose with starch (MD: -0.14 mmol/L; 95% CI: -0.29, 0.01 mmol/L; SUCRAstarch: 91%). Replacing fructose with an equivalent energy amount of glucose reduced HOMA-IR (MD: -0.36; 95% CI: -0.71, -0.02; SUCRAglucose: 74%) and uric acid (MD: -23.77 µmol/L; 95% CI: -44.21, -3.32 µmol/L; SUCRAglucose: 93%). The certainty of evidence was rated very low to moderate. No significant effects were observed for TG, HbA1c, CRP, ALT, and AST.

CONCLUSIONS

Our findings indicate that substitution of sucrose and fructose with starch yielded lower LDL cholesterol. Insulin resistance and uric acid concentrations were beneficially affected by replacement of fructose with glucose. Our findings are limited by the very low to moderate certainty of evidence. This review was registered at www.crd.york.ac.uk/prospero as CRD42018080297.

Suppressive effects of whey protein hydrolysate on sucrose-induced hyperglycemia in silkworms

Silkworms are useful for evaluating substances that suppress postprandial hyperglycemia by oral administration. In this study, orally administered whey protein hydrolysate (WPH), obtained by enzymatic treatment of whey protein, suppressed sucrose-induced hyperglycemia in silkworms in a dose-dependent manner. WPH also inhibited glucose-induced hyperglycemia in silkworms. These findings suggest that WPH contains a bioactive peptide that inhibits glucose uptake from the intestinal tract and thereby suppresses sucrose-induced hyperglycemia.

Review of the scientific evidence used for establishing US policies on added sugars

The 2015 Dietary Guidelines for Americans Advisory Committee has set recommendations to limit added sugars. This action was based on the association between dietary pattern quality scores and chronic disease risk, the results of meta-analyses conducted for the World Health Organization, and data from modeling of dietary patterns for establishing the US Department of Agriculture's Healthy US-Style Eating Patterns. Recommendations provided by the 2015-2020 Dietary Guidelines for Americans were used by the US Food and Drug Administration to establish, for the first time, the mandatory declaration of added sugars and a Daily Value of added sugars for the Nutrition Facts label. This review provides an overview of the scientific evidence considered by the World Health Organization, the 2015-2020 Dietary Guidelines for Americans, and the US Food and Drug Administration for setting recent polices and regulations on added sugars and highlights important issues and inconsistencies in the evaluations and interpretations of the evidence.

Enterococcus faecalis YM0831 suppresses sucrose-induced hyperglycemia in a silkworm model and in humans

Hyperglycemia caused by excessive intake of sucrose leads to lifestyle-related diseases such as diabetes. Administration of a lactic acid bacterial strain to mice suppresses sucrose-induced hyperglycemia, but evidence for a similar effect in humans is lacking. Here we show that Enterococcus faecalis YM0831, identified using an in vivo screening system with silkworms, suppressed sucrose-induced hyperglycemia in humans. E. faecalis YM0831 also suppressed glucose-induced hyperglycemia in silkworms. E. faecalis YM0831 inhibited glucose uptake by the human intestinal epithelial cell line Caco-2. A transposon insertion mutant of E. faecalis YM0831, which showed decreased inhibitory activity against glucose uptake by Caco-2 cells, also exhibited decreased inhibitory activity against both sucrose-induced and glucose-induced hyperglycemia in silkworms. In human clinical trials, oral ingestion of E. faecalis YM0831 suppressed the increase in blood glucose in a sucrose tolerance test. These findings suggest that E. faecalis YM0831 inhibits intestinal glucose transport and suppresses sucrose-induced hyperglycemia in humans.

Are Fruit Juices Healthier Than Sugar-Sweetened Beverages? A Review

Free sugars overconsumption is associated with an increased prevalence of risk factors for metabolic diseases such as the alteration of the blood lipid levels. Natural fruit juices have a free sugar composition quite similar to that of sugar-sweetened beverages. Thus, could fruit juice consumption lead to the same adverse effects on health as sweetened beverages? We attempted to answer this question by reviewing the available evidence on the health effects of both sugar-sweetened beverages and natural fruit juices. We determined that, despite the similarity of fruits juices to sugar-sweetened beverages in terms of free sugars content, it remains unclear whether they lead to the same metabolic consequences if consumed in equal dose. Important discrepancies between studies, such as type of fruit juice, dose, duration, study design, and measured outcomes, make it impossible to provide evidence-based public recommendations as to whether the consumption of fruit juices alters the blood lipid profile. More randomized controlled trials comparing the metabolic effects of fruit juice and sugar-sweetened beverage consumption are needed to shape accurate public health guidelines on the variety and quantity of free sugars in our diet that would help to prevent the development of obesity and related health problems.

Food sources of fructose-containing sugars and glycaemic control: systematic review and meta-analysis of controlled intervention studies

OBJECTIVE

To assess the effect of different food sources of fructose-containing sugars on glycaemic control at different levels of energy control.

DESIGN

Systematic review and meta-analysis of controlled intervention studies.

DATA SOURCES

Medine, Embase, and the Cochrane Library up to 25 April 2018.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Controlled intervention studies of at least seven days' duration and assessing the effect of different food sources of fructose-containing sugars on glycaemic control in people with and without diabetes were included. Four study designs were prespecified on the basis of energy control: substitution studies (sugars in energy matched comparisons with other macronutrients), addition studies (excess energy from sugars added to diets), subtraction studies (energy from sugars subtracted from diets), and ad libitum studies (sugars freely replaced by other macronutrients without control for energy). Outcomes were glycated haemoglobin (HbA1c), fasting blood glucose, and fasting blood glucose insulin.

DATA EXTRACTION AND SYNTHESIS

Four independent reviewers extracted relevant data and assessed risk of bias. Data were pooled by random effects models and overall certainty of the evidence assessed by the GRADE approach (grading of recommendations assessment, development, and evaluation).

RESULTS

155 study comparisons (n=5086) were included. Total fructose-containing sugars had no harmful effect on any outcome in substitution or subtraction studies, with a decrease seen in HbA1c in substitution studies (mean difference -0.22% (95% confidence interval to -0.35% to -0.08%), -25.9 mmol/mol (-27.3 to -24.4)), but a harmful effect was seen on fasting insulin in addition studies (4.68 pmol/L (1.40 to 7.96)) and ad libitum studies (7.24 pmol/L (0.47 to 14.00)). There was interaction by food source, with specific food sources showing beneficial effects (fruit and fruit juice) or harmful effects (sweetened milk and mixed sources) in substitution studies and harmful effects (sugars-sweetened beverages and fruit juice) in addition studies on at least one outcome. Most of the evidence was low quality.

CONCLUSIONS

Energy control and food source appear to mediate the effect of fructose-containing sugars on glycaemic control. Although most food sources of these sugars (especially fruit) do not have a harmful effect in energy matched substitutions with other macronutrients, several food sources of fructose-containing sugars (especially sugars-sweetened beverages) adding excess energy to diets have harmful effects. However, certainty in these estimates is low, and more high quality randomised controlled trials are needed.

STUDY REGISTRATION

Clinicaltrials.gov (NCT02716870).

Pathways and mechanisms linking dietary components to cardiometabolic disease: thinking beyond calories

Calories from any food have the potential to increase risk for obesity and cardiometabolic disease because all calories can directly contribute to positive energy balance and fat gain. However, various dietary components or patterns may promote obesity and cardiometabolic disease by additional mechanisms that are not mediated solely by caloric content. Researchers explored this topic at the 2017 CrossFit Foundation Academic Conference 'Diet and Cardiometabolic Health - Beyond Calories', and this paper summarizes the presentations and follow-up discussions. Regarding the health effects of dietary fat, sugar and non-nutritive sweeteners, it is concluded that food-specific saturated fatty acids and sugar-sweetened beverages promote cardiometabolic diseases by mechanisms that are additional to their contribution of calories to positive energy balance and that aspartame does not promote weight gain. The challenges involved in conducting and interpreting clinical nutritional research, which preclude more extensive conclusions, are detailed. Emerging research is presented exploring the possibility that responses to certain dietary components/patterns are influenced by the metabolic status, developmental period or genotype of the individual; by the responsiveness of brain regions associated with reward to food cues; or by the microbiome. More research regarding these potential 'beyond calories' mechanisms may lead to new strategies for attenuating the obesity crisis.

French Recommendations for Sugar Intake in Adults: A Novel Approach Chosen by ANSES

This article presents a systematic review of the scientific evidence linking sugar consumption and health in the adult population performed by a group of experts, mandated by the French Agence nationale de sécurité sanitaire de l’alimentation, de l’environnement, et du travail (ANSES). A literature search was performed by crossing search terms for overweight/obesity, diabetes/insulin resistance, dyslipidemia/cardiovascular diseases, non-alcoholic fatty liver diseases (NAFLD), and uric acid concentrations on one hand and for intake of sugars on the other. Controlled mechanistic studies, prospective cohort studies, and randomized clinical trials were extracted and assessed. A literature analysis supported links between sugar intake and both total energy intake and body weight gain, and between sugar intake and blood triglycerides independently of total energy intake. The effects of sugar on blood triglycerides were shown to be mediated by the fructose component of sucrose and were observed with an intake of fructose >50 g/day. In addition, prospective cohort studies showed associations between sugar intake and the risk of diabetes/insulin resistance, cardiovascular diseases, NAFLD, and hyperuricemia. Based on these observations, ANSES proposed to set a maximum limit to the intake of total sugars containing fructose (sucrose, glucose–fructose syrups, honey or other syrups, and natural concentrates, etc.) of 100 g/day.

Impact of Immunosuppression on the Metagenomic Composition of the Intestinal Microbiome: a Systems Biology Approach to Post-Transplant Diabetes

Solid organ transplantation (SOT) outcomes have continued to improve, although long-term use of immunosuppressants can lead to complications such as diabetes, compromising post-transplant outcomes. In this study, we have characterized the intestinal microbiome (IM) composition at the metagenomic level in the context of hyperglycemia induced by immunosuppressants. Sprague-Dawley rats were subjected to doses of tacrolimus and sirolimus that reliably induce hyperglycemia and an insulin-resistant state. Subsequent exposure to probiotics resulted in reversal of hyperglycemia. 16S rRNA and metagenomic sequencing of stool were done to identify the bacterial genes and pathways enriched in immunosuppression. Bacterial diversity was significantly decreased in sirolimus-treated rats, with 9 taxa significantly less present in both immunosuppression groups: Roseburia, Oscillospira, Mollicutes, Rothia, Micrococcaceae, Actinomycetales and Staphylococcus. Following probiotics, these changes were reversed to baseline. At the metagenomic level, the balance of metabolism was shifted towards the catabolic side with an increase of genes involved in sucrose degradation, similar to diabetes. Conversely, the control rats had greater abundance of anabolic processes and genes involved in starch degradation. Immunosuppression leads to a more catabolic microbial profile, which may influence development of diabetes after SOT. Modulation of the microbiome with probiotics may help in minimizing adverse long-term effects of immunosuppression.

Effects of free sugars on blood pressure and lipids: a systematic review and meta-analysis of nutritional isoenergetic intervention trials

BACKGROUND

Sugar has been suggested as a central risk factor in the development of noncommunicable diseases.

OBJECTIVE

We assessed the evidence of the effects of free sugars compared with complex carbohydrates on selected cardiovascular disease risk factors.

DESIGN

We conducted a systematic review and meta-analysis of intervention trials to compare diets that provide a given amount of energy from free sugars with a control diet that provides the same amount of energy from complex carbohydrates. The primary outcomes were: blood pressure, total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, triacylglycerols, apolipoproteins A-I and B, or very low-density lipoprotein cholesterol. Body weight was also recorded but was not a primary outcome of the studies.

RESULTS

In all, 28 studies involving 510 volunteers were included. When free sugars were substituted for complex carbohydrates, no significant increases were detected in systolic or diastolic blood pressure, and no heterogeneity was observed. There were significant increases in HDL cholesterol, LDL cholesterol, and triacylglycerols, although for LDL cholesterol and triacylglycerols there was significant heterogeneity between studies and evidence of publication bias. After adjustment for missing studies, these increases lost significance. Subgroup analyses showed that diets providing the largest total energy intake and energy exchange enhanced the effect of free sugars on total and LDL cholesterol and triacylglycerols. The increase of triacylglycerols was no longer significant when studies with the highest risk of bias were excluded or when only randomized trials were considered. Free sugars had no effect on body weight.

CONCLUSIONS

In short- or moderate-term isoenergetic intervention trials, the substitution of free sugars for complex carbohydrates had no effect on blood pressure or body weight and an unclear effect on blood lipid profile. Further independent trials are required to assess whether the reduction of free sugars improves cardiovascular disease risk factors. This review was registered at http://www.crd.york.ac.uk/prospero as CRD42016042930.

Nutrition in Type 2 Diabetes and the Metabolic Syndrome

For individuals at risk for type 2 diabetes mellitus or the metabolic syndrome, adherence to an idealized dietary pattern can drastically alter the risk and course of these chronic conditions. Target levels of carbohydrate intake should approximate 30% of consumed calories. Healthy food choices should include copious fruits, vegetables, and nuts while minimizing foods with high glycemic indices, especially processed foods.

An in vivo invertebrate evaluation system for identifying substances that suppress sucrose-induced postprandial hyperglycemia

Sucrose is a major sweetener added to various foods and beverages. Excessive intake of sucrose leads to increases in blood glucose levels, which can result in the development and exacerbation of lifestyle-related diseases such as obesity and diabetes. In this study, we established an in vivo evaluation system using silkworms to explore substances that suppress the increase in blood glucose levels caused by dietary intake of sucrose. Silkworm hemolymph glucose levels rapidly increased after intake of a sucrose-containing diet. Addition of acarbose or voglibose, α-glycosidase inhibitors clinically used for diabetic patients, suppressed the dietary sucrose-induced increase in the silkworm hemolymph glucose levels. Screening performed using the sucrose-induced postprandial hyperglycemic silkworm model allowed us to identify some lactic acid bacteria that inhibit the increase in silkworm hemolymph glucose levels caused by dietary intake of sucrose. The inhibitory effects of the Lactococcus lactis #Ll-1 bacterial strain were significantly greater than those of different strains of lactic acid bacteria. No effect of the Lactococcus lactis #Ll-1 strain was observed in silkworms fed a glucose diet. These results suggest that the sucrose diet-induced postprandial hyperglycemic silkworm is a useful model for evaluating chemicals and lactic acid bacteria that suppress increases in blood glucose levels.

Sugar consumption, metabolic disease and obesity: The state of the controversy

The impact of sugar consumption on health continues to be a controversial topic. The objective of this review is to discuss the evidence and lack of evidence that allows the controversy to continue, and why resolution of the controversy is important. There are plausible mechanisms and research evidence that supports the suggestion that consumption of excess sugar promotes the development of cardiovascular disease (CVD) and type 2 diabetes (T2DM) both directly and indirectly. The direct pathway involves the unregulated hepatic uptake and metabolism of fructose, leading to liver lipid accumulation, dyslipidemia, decreased insulin sensitivity and increased uric acid levels. The epidemiological data suggest that these direct effects of fructose are pertinent to the consumption of the fructose-containing sugars, sucrose and high fructose corn syrup (HFCS), which are the predominant added sugars. Consumption of added sugar is associated with development and/or prevalence of fatty liver, dyslipidemia, insulin resistance, hyperuricemia, CVD and T2DM, often independent of body weight gain or total energy intake. There are diet intervention studies in which human subjects exhibited increased circulating lipids and decreased insulin sensitivity when consuming high sugar compared with control diets. Most recently, our group has reported that supplementing the ad libitum diets of young adults with beverages containing 0%, 10%, 17.5% or 25% of daily energy requirement (Ereq) as HFCS increased lipid/lipoprotein risk factors for CVD and uric acid in a dose-response manner. However, un-confounded studies conducted in healthy humans under a controlled, energy-balanced diet protocol that enables determination of the effects of sugar with diets that do not allow for body weight gain are lacking. Furthermore, recent reports conclude that there are no adverse effects of consuming beverages containing up to 30% Ereq sucrose or HFCS, and the conclusions from several meta-analyses suggest that fructose has no specific adverse effects relative to any other carbohydrate. Consumption of excess sugar may also promote the development of CVD and T2DM indirectly by causing increased body weight and fat gain, but this is also a topic of controversy. Mechanistically, it is plausible that fructose consumption causes increased energy intake and reduced energy expenditure due to its failure to stimulate leptin production. Functional magnetic resonance imaging (fMRI) of the brain demonstrates that the brain responds differently to fructose or fructose-containing sugars compared with glucose or aspartame. Some epidemiological studies show that sugar consumption is associated with body weight gain, and there are intervention studies in which consumption of ad libitum high-sugar diets promoted increased body weight gain compared with consumption of ad libitum low- sugar diets. However, there are no studies in which energy intake and weight gain were compared in subjects consuming high or low sugar, blinded, ad libitum diets formulated to ensure both groups consumed a comparable macronutrient distribution and the same amounts of fiber. There is also little data to determine whether the form in which added sugar is consumed, as beverage or as solid food, affects its potential to promote weight gain. It will be very challenging to obtain the funding to conduct the clinical diet studies needed to address these evidence gaps, especially at the levels of added sugar that are commonly consumed. Yet, filling these evidence gaps may be necessary for supporting the policy changes that will help to turn the food environment into one that does not promote the development of obesity and metabolic disease.

A dose-response study of consuming high-fructose corn syrup-sweetened beverages on lipid/lipoprotein risk factors for cardiovascular disease in young adults

BACKGROUND

National Health and Nutrition Examination Survey data show an increased risk of cardiovascular disease (CVD) mortality with an increased intake of added sugar.

OBJECTIVE

We determined the dose-response effects of consuming beverages sweetened with high-fructose corn syrup (HFCS) at zero, low, medium, and high proportions of energy requirements (Ereq) on circulating lipid/lipoprotein risk factors for CVD and uric acid in adults [age: 18-40 y; body mass index (in kg/m(2)): 18-35].

DESIGN

We conducted a parallel-arm, nonrandomized, double-blinded intervention study in which adults participated in 3.5 inpatient days of baseline testing at the University of California Davis Clinical and Translational Science Center's Clinical Research Center. Participants then consumed beverages sweetened with HFCS at 0% (aspartame sweetened, n = 23), 10% (n = 18), 17.5% (n = 16), or 25% (n = 28) of Ereq during 13 outpatient days and during 3.5 inpatient days of intervention testing at the research center. We conducted 24-h serial blood collections during the baseline and intervention testing periods.

RESULTS

Consuming beverages containing 10%, 17.5%, or 25% Ereq from HFCS produced significant linear dose-response increases of lipid/lipoprotein risk factors for CVD and uric acid: postprandial triglyceride (0%: 0 ± 4; 10%: 22 ± 8; 17.5%: 25 ± 5: 25%: 37 ± 5 mg/dL, mean of Δ ± SE, P < 0.0001 effect of HFCS-dose), fasting LDL cholesterol (0%: -1.0 ± 3.1; 10%: 7.4 ± 3.2; 17.5%: 8.2 ± 3.1; 25%: 15.9 ± 3.1 mg/dL, P < 0.0001), and 24-h mean uric acid concentrations (0%: -0.13 ± 0.07; 10%: 0.15 ± 0.06; 17.5%: 0.30 ± 0.07; 25%: 0.59 ± 0.09 mg/dL, P < 0.0001). Compared with beverages containing 0% HFCS, all 3 doses of HFCS-containing beverages increased concentrations of postprandial triglyceride, and the 2 higher doses increased fasting and/or postprandial concentrations of non-HDL cholesterol, LDL cholesterol, apolipoprotein B, apolipoprotein CIII, and uric acid.

CONCLUSIONS

Consuming beverages containing 10%, 17.5%, or 25% Ereq from HFCS produced dose-dependent increases in circulating lipid/lipoprotein risk factors for CVD and uric acid within 2 wk. These results provide mechanistic support for the epidemiologic evidence that the risk of cardiovascular mortality is positively associated with consumption of increasing amounts of added sugars. This trial was registered at clinicaltrials.gov as NCT01103921.

Relevance of liver fat to the impact of dietary extrinsic sugars on lipid metabolism

In contrast to the decline in mortality from many non-infectious, chronic diseases in the UK, death from liver disease has increased exponentially in men and women over the past 40 years. This is primarily because of the over consumption of alcohol, but also the increased prevalence of obesity, which is linked to early pathology through the accumulation of liver fat. Supra-physiological intakes of fructose-containing sugar can produce acute, adverse effects on lipid metabolism, and deliver excess energy that increases bodyweight and the deposition of fat in sites other than adipose tissue, including the liver. This review addresses the variable metabolic origins of liver fat, and the key importance of postprandial lipid metabolism in this respect. The effects of supra-physiological intakes of sugar are also considered in context of the real world and established threshold for the adverse effects of sugar on cardio-metabolic risk factors. The review concludes that while the average intake of sugar in the UK falls well below this critical threshold, intakes in subgroups of adults, and especially adolescents, may be cause for concern. There is also evidence to suggest that raised liver fat, acquired, in part, through an impaired removal of postprandial lipaemia, can increase sensitivity to the adverse effects of sugar at all ages.

Dietary sugars and cardiometabolic risk: systematic review and meta-analyses of randomized controlled trials of the effects on blood pressure and lipids

BACKGROUND

Dietary sugars have been suggested as a cause of obesity, several chronic diseases, and a range of cardiometabolic risk factors, but there is no convincing evidence of a causal relation between sugars and risk factors other than body weight.

OBJECTIVE

We conducted a systematic review and meta-analysis of randomized controlled trials that examined effects of the modification of dietary free sugars on blood pressure and lipids.

DESIGN

Systematic searches were conducted in OVID Medline, Embase, Scopus, Cumulative Index to Nursing and Allied Health Literature, and Web of Science databases (to August 2013) to identify studies that reported intakes of free sugars and at least one lipid or blood pressure outcome. The minimum trial duration was 2 wk. We pooled data by using inverse-variance methods with random-effects models.

RESULTS

A total of 39 of 11,517 trials identified were included; 37 trials reported lipid outcomes, and 12 trials reported blood pressure outcomes. Higher compared with lower sugar intakes significantly raised triglyceride concentrations [mean difference (MD): 0.11 mmol/L; 95% CI: 0.07, 0.15 mmol/L; P < 0.0001], total cholesterol (MD: 0.16 mmol/L; 95% CI: 0.10, 0.24 mmol/L; P < 0.0001), low-density lipoprotein cholesterol (0.12 mmol/L; 95% CI: 0.05, 0.19 mmol/L; P = 0.0001), and high-density lipoprotein cholesterol (MD: 0.02 mmol/L; 95% CI: 0.00, 0.03 mmol/L; P = 0.03). Subgroup analyses showed the most marked relation between sugar intakes and lipids in studies in which efforts were made to ensure an energy balance and when no difference in weight change was reported. Potential explanatory factors, including a weight change, in most instances explained <15% of the heterogeneity between studies (I(2) = 36-75%). The effect of sugar intake on blood pressure was greatest in trials ≥8 wk in duration [MD: 6.9 mm Hg (95% CI: 3.4, 10.3 mm Hg; P < 0.001) for systolic blood pressure and 5.6 mm Hg (95% CI: 2.5, 8.8 mm Hg; P = 0.0005) for diastolic blood pressure].

CONCLUSIONS

Dietary sugars influence blood pressure and serum lipids. The relation is independent of effects of sugars on body weight. Protocols for this review were registered separately for effects of sugars on blood pressure and lipids in the PROSPERO International prospective register of systematic reviews as PROSPERO 2012: CRD42012002379 and 2012: CRD42012002437, respectively.

Weight classification does not influence the short-term endocrine or metabolic effects of high-fructose corn syrup-sweetened beverages

Obesity and high-fructose corn syrup (HFCS)-sweetened beverages are associated with an increased risk of chronic disease, but it is not clear whether obese (Ob) individuals are more susceptible to the detrimental effects of HFCS-sweetened beverages. The purpose of this study was to examine the endocrine and metabolic effects of consuming HFCS-sweetened beverages, and whether weight classification (normal weight (NW) vs. Ob) influences these effects. Ten NW and 10 Ob men and women who habitually consumed ≤355 mL per day of sugar-sweetened beverages were included in this study. Initially, the participants underwent a 4-h mixed-meal test after a 12-h overnight fast to assess insulin sensitivity, pancreatic and gut endocrine responses, insulin secretion and clearance, and glucose, triacylglycerol, and cholesterol responses. Next, the participants consumed their normal diet ad libitum, with 1065 mL per day (117 g·day(-1)) of HFCS-sweetened beverages added for 2 weeks. After the intervention, the participants repeated the mixed-meal test. HFCS-sweetened beverages did not significantly alter body weight, insulin sensitivity, insulin secretion or clearance, or endocrine, glucose, lipid, or cholesterol responses in either NW or Ob individuals. Regardless of previous diet, Ob individuals, compared with NW individuals, had ∼28% lower physical activity levels, 6%-9% lower insulin sensitivity, 12%-16% lower fasting high-density-lipoprotein cholesterol concentrations, 84%-144% greater postprandial triacylglycerol concentrations, and 46%-79% greater postprandial insulin concentrations. Greater insulin responses were associated with reduced insulin clearance, and there were no differences in insulin secretion. These findings suggest that weight classification does not influence the short-term endocrine and metabolic effects of HFCS-sweetened beverages.

The inflammatory profile and liver damage of a sucrose-rich diet in mice

It is still unclear if an isoenergetic, sucrose-rich diet leads to health consequences.

AIMS

To investigate the effects of excessive sucrose within an isoenergetic diet on metabolic parameters in male C57BL/6 mice.

METHODS

Animals were fed a control diet (10% fat, 8% sucrose - SC group), a high-sucrose diet (10% fat, 32% sucrose - HSu group), a high-fat diet (42% fat, 8% sucrose - HF group) or a high-fat/high-sucrose diet (42% fat, 32% sucrose - HF/HSu group) for 8 weeks.

RESULTS

Mice fed HF and HF/HSu diets gained more body mass (BM) and more body adiposity than SC- or Hsu-fed mice. Despite the unchanged BM and adiposity indices, HSu mice presented adipocyte hypertrophy, which was also observed in the HF and HF/HSu groups (P<.0001). The HF, HSu and HF/HSu mice were glucose intolerant and had elevated serum insulin levels (P<.05). The levels of leptin, resistin and monocyte chemotactic protein-1 increased, while the serum adiponectin decreased in the HF, HSu and HF/HSu groups (P<.05). In the adipose tissue, the HF, HSu and HF/HSu groups showed higher levels of leptin expression and lower levels of adiponectin expression in comparison with the SC group (P<.05). Liver steatosis was higher in the HF, HSu and HF/HSu groups than in the SC group (P<.0001). Hepatic cholesterol was higher in the HF and HF/HSu groups, while hepatic TG was higher in the HSu and HF/HSu groups (P<.05). In hepatic tissue, the sterol receptor element-binding protein-1c expression was increased in the HF, HSu and HF/HSu groups, unlike the peroxisome proliferator-activated receptor-alpha expression that decreased in the HF, HSu and HF/HSu groups in comparison with the SC group (P<.05).

CONCLUSION

A sucrose-rich diet does not lead to a state of obesity but has the potential to cause changes in the adipocytes (hypertrophy) as well as glucose intolerance, hyperinsulinemia, hyperlipidemia, hepatic steatosis and increases in the number of inflammatory cytokines. The deleterious effects of a sucrose-rich diet in an animal model, even when the sucrose replaces starch isocalorically in the feed, can have far-reaching consequences for health.