Free sugar intake is associated with reduced proportion of circulating invariant natural killer T cells among women experiencing overweight and obesity.

Background: Higher prevalence of obesity has been observed among women compared to men, which can be explained partly by the higher consumption of sweets and physical inactivity. Obesity can alter immune cell infiltration, and therefore increase the susceptibility to develop chronic inflammation and metabolic disorders. In this study, we aimed to explore the association between free sugar intake and other unhealthy lifestyle habits in relation to the proportion of circulating iNKT cells among women with healthy weight and women experiencing overweight and obesity. Methods: A cross-sectional study was conducted on 51 Saudi women > 18 years, wherein their daily free sugar intake was assessed using the validated Food Frequency Questionnaire. Data on smoking status, physical activity, and supplement use were also collected. Anthropometric data including height, weight, waist circumference were objectively measured from each participants. The proportion of circulating iNKT cells was determined using flow cytometry. Results: Smoking, physical activity, supplement use, and weight status were not associated with proportion of circulating iNKT cells. Significant association was found between proportion of circulating iNKT cells and total free sugar intake and free sugar intake coming from solid food sources only among women experiencing overweight and obesity (Beta: -0.10: Standard Error: 0.04 [95% Confidence Interval: -0.18 to -0.01], p= 0.034) and (Beta: -0.15: Standard Error: 0.05 [95% Confidence Interval: -0.25 to -0.05], p= 0.005), respectively. Conclusion: Excessive free sugar consumption may alter iNKT cells and consequently increase the risk for chronic inflammation and metabolic disorders.

Higher Sugar Intake Associated with Higher Risk of Depression.

According to this study.

Sugar types, genetic predictors of the gut microbiome, and the risk of chronic kidney disease: a prospective cohort study.

Background: Emerging studies suggest that focusing on the intake of specific types or sources of sugars may yield greater benefits in preventing chronic kidney disease (CKD). Objective: We aimed to investigate the associations between free and non-free sugar intakes and CKD risk as well as the potential sugar type-gut microbiome interactions. Methods: A total of 138 064 participants from the UK Biobank were included in this prospective study. The free and non-free sugar intakes were assessed using repeated web-based 24-hour dietary recalls. A cause-specific competing risk model was used to estimate hazard ratios (HRs) and the corresponding confidence intervals (CIs) of incident CKD, treating deaths before incident CKD as competing events. Results: During a median follow-up of 10.5 years, 2,923 participants (2.1%) developed CKD. The free sugar intake was positively associated with the risk of CKD (HRquartile 4 vs. quartile 1 = 1.32, 95% CI = 1.18, 1.47), with a nonlinear relationship (P for nonlinearity = 0.01, the risk increased rapidly after free sugars made up 10% of the total energy). The non-free sugar intake was inversely associated with CKD risk (HRquartile 4 vs. quartile 1 = 0.68, 95% CI = 0.60, 0.77), with an L-shaped nonlinear curve (p for nonlinearity = 0.01, the turning point was at 13.5% of the total energy). We found that the associations between free sugar and non-free sugar intakes and CKD risk were more pronounced in participants with high genetically predicted gut microbial abundance. Furthermore, a significant interaction was observed between the genetically predicted gut microbial abundance and non-free sugar intake (P for interaction = 0.04). Conclusion: A higher intake of free sugars was associated with an elevated risk of CKD, whereas a higher intake of non-free sugars was associated with a reduced risk of CKD. The impact of free sugar intake and non-free sugar intake may be modified by the gut microbial abundance.

Association between dietary sugar intake and depression in US adults: a cross-sectional study using data from the National Health and Nutrition Examination Survey 2011-2018.

BACKGROUND: Studies examining whether diet sugar intake increases the risk of depression have produced inconsistent results. Therefore, we investigated this relationship, using the US' National Health and Nutrition Examination Survey (NHANES) database. METHODS: This cross-sectional study included 18,439 adults (aged ≥ 20 years) from NHANES (2011-2018). Depressive symptoms were assessed using the nine-item version of the Patient Health Questionnaire (PHQ-9). Covariates, including age, sex, race/ethnicity, poverty-income ratio, education, marital status, hypertension, diabetes mellitus, cardiovascular disease, alcohol intake, smoking status, physical activity, and dietary energy intake, were adjusted in multivariate logistic regression models. Subgroup and threshold saturation effect analyses were performed. RESULTS: After adjusting for potential confounders, we found that a 100 g/day increase in dietary sugar intake correlated with a 28% higher prevalence of depression (odds ratio = 1.28, 95% confidence interval = 1.17-1.40, P < 0.001). CONCLUSION: Dietary sugar intake is positively associated with depression in US adults.

A scoping study on the social determinants of health and sugar consumption in the context of policy approaches for improving population health.

OBJECTIVES: To conduct a scoping review of existing research on the social determinants of health, sugar consumption and public health policy responses to address or improve health outcomes. METHODS: A total of 13 categories were developed to reflect the authors' interest in the overall focus on the social determinants of health, sugar as an independent risk factor, upstream policy action ('whole populations'), downstream policy action ('targeted') and two contemporary policy strategies (namely 'Vulnerable populations' and 'Proportionate Universalism'). The search strategy was then performed on MEDLINE (via Ovid) and Web of Science, and was limited to the English language. No time limits prior to when the database search was conducted in 2022 were set to explore the full extent of the literature in this field. RESULTS: Five hundred and sixty articles were retrieved, of which 181 met the criteria for review. When all categories were applied, the findings showed that 76% of papers focusing on sugar consumption as a risk factor for non-communicable diseases (NCDs) mentioned the social determinants of health. The majority of studies (60%) recommended downstream interventions, with 40% recommending 'upstream' interventions. A limited proportion (12%) of research work was published in dental journals. Research had been done using predominantly quantitative methods (66% of articles), with 24% of studies adopting a mixed methods approach, and 8% being exclusively qualitative. Research on contemporary strategies for sugar reduction were focused on the 'Global North' and 98% of papers used individual level data focused on targeted approaches, highlighting that there is little direct evidence for contemporary strategies aimed at reducing sugar consumption. CONCLUSIONS: Whilst the majority of public and dental health research argues that there is a need to address the social determinants of health, the findings from this study highlight that very few empirical studies have been designed to directly inform contemporary strategies for sugar reduction. More research is therefore needed that can directly assess the evidence for contemporary strategies in public health policy.

The Impact and Burden of Dietary Sugars on the Liver.

NAFLD, or metabolic dysfunction-associated steatotic liver disease, has increased in prevalence hand in hand with the rise in obesity and increased free sugars in the food supply. The causes of NAFLD are genetic in origin combined with environmental drivers of the disease phenotype. Dietary intake of added sugars has been shown to have a major role in the phenotypic onset and progression of the disease. Simple sugars are key drivers of steatosis, likely through fueling de novo lipogenesis, the conversion of excess carbohydrates into fatty acids, but also appear to upregulate lipogenic metabolism and trigger hyperinsulinemia, another driver. NAFLD carries a clinical burden as it is associated with obesity, type 2 diabetes, metabolic syndrome, and cardiovascular disease. Patient quality of life is also impacted, and there is an enormous economic burden due to healthcare use, which is likely to increase in the coming years. This review aims to discuss the role of dietary sugar in NAFLD pathogenesis, the health and economic burden, and the promising potential of sugar reduction to improve health outcomes for patients with this chronic liver disease.

Associations of dietary sugar types with coronary heart disease risk: a prospective cohort study.

BACKGROUND: Higher intake of total sugar has been linked with coronary heart disease (CHD) risk, but the role of individual sugars, particularly fructose, is uncertain. OBJECTIVES: This study aimed to investigate the associations of individual dietary sugars with CHD risk. METHODS: In prospective cohort studies, we followed 76,815 women (Nurses' Health Study, 1980-2020) and 38,878 men (Health Professionals Follow-up Study, 1986-2016). Sugar and carbohydrate intake, including total fructose equivalents ([TFE] from fructose monosaccharides and sucrose), total glucose equivalents ([TGE] from glucose monosaccharides, disaccharides, and starch), and other sugar types, was measured every 2 to 4 y by semiquantitative food frequency questionnaires. RESULTS: We documented 9,723 incident CHD cases over 40 years. In isocaloric substitution models with total fat as a comparison nutrient, comparing extreme quintiles of intake, hazard ratios (HRs), 95% confidence interval [CI]) for CHD risk were 1.31 (1.20 to 1.42; Ptrend < 0.001) for TGE and 1.03 (0.94 to 1.11; Ptrend = 0.25) for TFE. TFE from fruits and vegetables was not associated with CHD risk (Ptrend = 0.70), but TFE from added sugar and juice was associated with CHD risk (HR: 1.12, 95% CI: 1.04 to 1.20; Ptrend < 0.01). Intakes of total sugars and added sugar were positively associated with CHD risk (HRs: 1.16, 95% CI: 1.07 to 1.26, Ptrend < 0.001; 1.08, 95% CI: 0.99 to 1.16, Ptrend = 0.04). CONCLUSIONS: Intakes of TGE, total sugar, added sugar, and fructose from added sugar and juice were associated with higher CHD risk, but TFE and fructose from fruits and vegetables were not.

High-Sucrose Diet Accelerates Arthritis Progression in a Collagen-Induced Rheumatoid Arthritis Model.

SCOPE: High dietary sugar and sweeteners are suspected to cause the development of rheumatoid arthritis (RA) symptoms through the induction of proinflammatory cytokine release. However, the mechanisms by which increased dietary sugar affects RA etiology are not yet fully understood. The study uses a mouse model of collagen-induced RA (CIA) to investigate the relationship between excessive sugar consumption and RA risk. METHODS AND RESULTS: RA-associated pathological features are assessed in the nonimmunized (NI) control group, the CIA-positive control group, and the CIA + high-sucrose diet (CIA+HS, 63% calories from sucrose) group. Compared with the CIA group, the CIA+HS group shows a greater increase in paw thickness and clinical scores, as well as, a higher degree of pannus formation and inflammation in the knee, ankle, and sole tissues. Moreover, the infiltration of immune cells is increased in the CIA+HS group. Although the expression of hepatic lipogenic genes, is not altered, that of toll-like receptor (TLR4) and IL-1ß is considerably elevated in the CIA+HS group. CONCLUSIONS: These findings suggest that excessive sucrose consumption causes hepatic fibrosis and inflammation, contributing to the pathophysiology of RA.

Protecting children from the harmful impact of food marketing.

A healthy and balanced diet should be promoted already in childhood, a crucial period for the psychophysical development of the individual. In particular, the consumption of free sugars and soft drinks in children and adolescents should not exceed the current WHO recommendations. This trend is very difficult to counter as the preference for sweet flavours is innate and often further reinforced by pre- and post-natal exposure and aggressive marketing. Unfortunately, sugar consumption continues to grow alarmingly due in part to the easy availability of foods and drinks rich in added sugars from vending machines, supermarkets and fast-food restaurants. Recently, the WHO (with the recommendations included in the QR Code below and in the following link: WHO recommends stronger policies to protect children from the harmful impact of food marketing) pointed out how exposure to food marketing affects children's health, eating behaviours and beliefs about food, thus becoming a real threat to public health. Among the proposals made, it is interesting to note the need for national governments to "curb the persuasive power of food marketing" by limiting the use of cartoons and other techniques that appeal to children, such as the inclusion of toys in packaging or advertisements with songs and celebrity endorsements. It is already evident in the literature that an excessive intake of sugar predisposes children to a number of pathological conditions that in the long term may favour the onset not only of carious disease but also obesity, type 2 diabetes mellitus, liver disease, cardiovascular and dysmetabolic diseases. As paediatric dentists, sugar-related dietary excesses are already very obvious to us since it is mainly these that drive young patients to our clinics. In our privileged position, we should therefore increasingly promote knowledge on the possible correlations between excessive sugar consumption and the onset of these diseases, drawing the attention of parents of young patients to all foods that are harmful to their growing children. Therefore, let us welcome these new guidelines promoted by the WHO to protect children and adolescents from the harmful impact of food marketing; and may we not miss the opportunity to share and promote this important battle for future generations!

Dietary sugar consumption and health: umbrella review.

OBJECTIVE: To evaluate the quality of evidence, potential biases, and validity of all available studies on dietary sugar consumption and health outcomes. DESIGN: Umbrella review of existing meta-analyses. DATA SOURCES: PubMed, Embase, Web of Science, Cochrane Database of Systematic Reviews, and hand searching of reference lists. INCLUSION CRITERIA: Systematic reviews and meta-analyses of randomised controlled trials, cohort studies, case-control studies, or cross sectional studies that evaluated the effect of dietary sugar consumption on any health outcomes in humans free from acute or chronic diseases. RESULTS: The search identified 73 meta-analyses and 83 health outcomes from 8601 unique articles, including 74 unique outcomes in meta-analyses of observational studies and nine unique outcomes in meta-analyses of randomised controlled trials. Significant harmful associations between dietary sugar consumption and 18 endocrine/metabolic outcomes, 10 cardiovascular outcomes, seven cancer outcomes, and 10 other outcomes (neuropsychiatric, dental, hepatic, osteal, and allergic) were detected. Moderate quality evidence suggested that the highest versus lowest dietary sugar consumption was associated with increased body weight (sugar sweetened beverages) (class IV evidence) and ectopic fatty accumulation (added sugars) (class IV evidence). Low quality evidence indicated that each serving/week increment of sugar sweetened beverage consumption was associated with a 4% higher risk of gout (class III evidence) and each 250 mL/day increment of sugar sweetened beverage consumption was associated with a 17% and 4% higher risk of coronary heart disease (class II evidence) and all cause mortality (class III evidence), respectively. In addition, low quality evidence suggested that every 25 g/day increment of fructose consumption was associated with a 22% higher risk of pancreatic cancer (class III evidence). CONCLUSIONS: High dietary sugar consumption is generally more harmful than beneficial for health, especially in cardiometabolic disease. Reducing the consumption of free sugars or added sugars to below 25 g/day (approximately 6 teaspoons/day) and limiting the consumption of sugar sweetened beverages to less than one serving/week (approximately 200-355 mL/week) are recommended to reduce the adverse effect of sugars on health. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42022300982.

Sugar intake and colorectal cancer risk: A prospective Japanese cohort study.

The influence of sugar consumption on the risk of colorectal cancer (CRC) remains controversial. Prospective cohort studies focusing on total and specific types of sugar intake among the Asian population who have different patterns of sugar intake sources than American and European populations are scarce. We intended to examine the association of sugar intake with CRC risk among middle-aged adults in a Japanese large-scale population-based cohort study. The participants (42,405 men and 48,600 women) who were 45-74 years old and answered the questionnaire in 1995-1999 in the Japan Public Health Center-based Prospective Study were followed up until December 2013. Total sugars, total fructose, and specific types of sugar intake were estimated using a validated 147-item food frequency questionnaire and divided into quintiles (Q1-Q5). We used Cox proportional hazard regression models adjusted for potential confounders to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). During the follow-up, 2118 CRC cases (1226 men and 892 women) were identified. We did not observe any clear association between all types of sugar intake and an increased risk of CRC. Analyses by tumor sites yielded a positive association of total sugar consumption with rectal cancer in women (1.75 [1.07-2.87] for Q1 vs. Q5; p linear trend  = 0.03), but no statistically significant trend was detected among men. Sugar intake was not associated with CRC risk in middle-aged Japanese adults. However, for rectal cancer, the probability of an increased risk among women with a higher total sugar intake cannot be excluded.

Different Sources of Sugar Consumption and Cognitive Performance in Older Adults: Data From the National Health and Nutrition Examination Survey 2011-2014.

OBJECTIVES: Excess sugar consumption, particularly in sugar-sweetened beverages (SSBs), has been linked to poor cognitive performance. We aimed to assess the association of consumption of total sugar, as well as the consumption of SSBs, solid desserts, and 100% fruit juice with cognitive performance among older adults. METHODS: Consumption of total sugar, SSBs, solid desserts, and 100% fruit juice were obtained from the 24-hr recall interview. Cognitive performance was evaluated using the Consortium to Establish a Registry for Alzheimer's Disease word list, the Animal Fluency Test, and the Digit Symbol Substitution Test. Binary logistic regression models were used to evaluate the association between consumption of sugar (total and from different sources) and cognitive performance. RESULTS: A total of 1,938 participants aged 60 years or older from the National Health and Nutrition Examination Survey 2011-2014 were included. Compared to the lowest tertile, the highest tertile of total sugar consumption was independently associated with higher odds of low memory performance (odds ratio [OR] = 1.87, 95% confidence interval [CI] = 1.00; 3.50, p = .049). Consumption of SSBs was associated with higher risk of low memory (OR = 1.58, 95% CI = 1.11; 2.25, p = .014), whereas consumption of solid desserts was associated with lower risk of low verbal fluency performance (OR = 0.62, 95% CI = 0.41; 0.95, p = .032). DISCUSSION: Higher consumption of total sugars and SSBs was associated with lower memory performance, while consumption of solid desserts was associated with higher verbal fluency performance.

Sugar Consumption Pattern among Cardiometabolic Risk Individuals: A Scoping Review.

BACKGROUND: The global prevalence of noncommunicable diseases has risen rapidly over the past decade. Research has focused on dietary management, particularly dietary sugar, to prevent and treat noncommunicable diseases. OBJECTIVE: This study undertakes a scoping review of research on the impacts of dietary sugar on cardiometabolic related health outcomes. METHODS: Ovid Medline, Scopus and Web of Science Core collection databases were used to identify papers published from January 1, 2010 onwards. The included studies had to be cross-sectional or cohort studies, peered review, published in English and in adults, aged 18 years old and above. Articles had to determine the impacts of sugar intake on cardiometabolic related health outcomes. Study quality was measured using the Quality Assessment Tool for Observational Cohort and Cross-sectional Studies. In addition, a narrative synthesis of extracted information was conducted. RESULTS: Thirty-one articles were included in this review. All studies had a large sample size, and the exposure measure was clearly defined, valid and applied consistently across all study participants. Exposure was measured using validated questionnaires. All data were statistically analysed and adjusted for critical potential confounding variables. Results showed that dietary sugar intake was significantly associated with metabolic syndrome, blood pressure, blood glucose, blood lipids, and body weight. CONCLUSION: Dietary sugar intake significantly increased cardiometabolic risks through mechanisms dependent and independent of weight gain. It is essential to create public awareness on the topics of cardiometabolic risk management and dietary sugars intake.

Prolonged breastfeeding, sugar consumption and dental caries at 2 years of age: A birth cohort study.

OBJECTIVES: Previous cohort studies have found a positive association between prolonged breastfeeding (≥12 months) on dental caries, but few of them analysed the mediated effect of sugar consumption on this association. This study investigated whether prolonged breastfeeding is a risk factor for caries at 2-year follow-up assessment (21-27 months of age) and whether this effect is mediated by sugar consumption. METHODS: A birth cohort study was performed in the Brazilian Amazon (n = 800). Dental caries was assessed using the dmf-t index. Prolonged breastfeeding was the main exposure. Data on baseline covariables and sugar consumption at follow-up visits were analysed. We estimated the OR for total causal effect (TCE) and natural indirect effect (NIE) of prolonged breastfeeding on dental caries using the G-formula. RESULTS: The prevalence of caries was 22.8% (95% CI: 19.8%-25.8%). Children who were breastfed for 12-23 months (TCE = 1.13, 95% CI: 1.05-1.20) and for ≥24 months (TCE = 1.27, 95% CI: 1.14-1.40) presented a higher risk of caries at age of 2 years than those breastfed <12 months. However, this risk was slightly mediated by a decreased frequency of sugar consumption at age of 2 years only for breastfeeding from 12 to 23 months (NIE; OR = 0.95, 95% CI: 0.91-0.97). CONCLUSIONS: In this study, the effect of prolonged breastfeeding on the increased risk of dental caries was slightly mediated by sugar consumption. Early feeding practices for caries prevention and promoting breastfeeding while avoiding sugar consumption should be targeted in the first 2 years of life.

The Impact of Free and Added Sugars on Cognitive Function: A Systematic Review and Meta-Analysis.

A relationship between excessive sugar consumption and cognitive function has been described in animal models, but the specific effects of sugars in humans remains unclear. This systematic review and meta-analysis aimed to evaluate the current knowledge, research characteristics, and quality of evidence of studies investigating the impacts of free and added sugars on human cognition in healthy participants. The review identified 77 studies (65 experimental trials, n = 3831; 9 cross-sectional studies, n = 11,456; and 3 cohort studies, n = 2059). All cohort studies and eight of the nine cross-sectional studies found significant positive correlations between added sugar consumption and risk of cognitive impairment. Four studies identified reduced risk of cognitive impairment associated with natural fructose-containing foods. The majority of randomised control trials assessed short-term glucose facilitation effects on cognitive outcomes. The results from these studies suggest the need for a tightly regulated blood glucose level, dependent on individualised physiological factors, for optimal cognitive function. A meta-analysis of a subset of studies that assessed the impact of glucose on recall found improvements in immediate free recall compared to controls (p = 0.002). The findings highlight the potentially detrimental effect of excessive, long-term, or prenatal added sugar consumption on cognitive function. Further research is needed to examine the specific effects of free and added sugars on cognitive function.

The Oral Microbiome Impacts the Link between Sugar Consumption and Caries: A Preliminary Study.

BACKGROUND: The excessive and frequent intake of refined sugar leads to caries. However, the relationship between the amount of sugar intake and the risk of caries is not always consistent. Oral microbial profile and function may impact the link between them. This study aims to identify the plaque microbiota characteristics of caries subjects with low (CL) and high (CH) sugar consumption, and of caries-free subjects with low (FL) and high sugar (FH) consumption. METHODS: A total of 40 adolescents were enrolled in the study, and supragingival plaque samples were collected and subjected to metagenomic analyses. The caries status, sugar consumption, and oral-health behaviors of the subjects were recorded. RESULTS: The results indicate that the CL group showed a higher abundance of several cariogenic microorganisms Lactobacillus, A. gerencseriae, A. dentails, S. mutans, C. albicans, S. wiggsiae and P. acidifaciens. C. gingivalis, and P. gingivalis, which were enriched in the FH group. In terms of gene function, the phosphotransferase sugar uptake system, phosphotransferase system, and several two-component responses-regulator pairs were enriched in the CL group. CONCLUSION: Overall, our data suggest the existence of an increased cariogenic microbial community and sugar catabolism potential in the CL group, and a healthy microbial community in the FH group, which had self-stabilizing functional potential.