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Purpose: It has been proposed that a higher habitual protein intake may increase cancer risk, possibly via upregulated insulin-like growth factor signalling. Since a systematic evaluation of human studies on protein intake and cancer risk based on a standardised assessment of systematic reviews (SRs) is lacking, we carried out an umbrella review of SRs on protein intake in relation to risks of different types of cancer. Methods: Following a pre-specified protocol (PROSPERO: CRD42018082395), we retrieved SRs on protein intake and cancer risk published before January 22th 2024, and assessed the methodological quality and outcome-specific certainty of the evidence using a modified version of AMSTAR 2 and NutriGrade, respectively. The overall certainty of evidence was rated according to predefined criteria. Results: Ten SRs were identified, of which eight included meta-analyses. Higher total protein intake was not associated with risks of breast, prostate, colorectal, ovarian, or pancreatic cancer incidence. The methodological quality of the included SRs ranged from critically low (kidney cancer), low (pancreatic, ovarian and prostate cancer) and moderate (breast and prostate cancer) to high (colorectal cancer). The outcome-specific certainty of the evidence underlying the reported findings on protein intake and cancer risk ranged from very low (pancreatic, ovarian and prostate cancer) to low (colorectal, ovarian, prostate, and breast cancer). Animal and plant protein intakes were not associated with cancer risks either at a low (breast and prostate cancer) or very low (pancreatic and prostate cancer) outcome-specific certainty of the evidence. Overall, the evidence for the lack of an association between protein intake and (i) colorectal cancer risk and (ii) breast cancer risk was rated as possible. By contrast, the evidence underlying the other reported results was rated as insufficient. Conclusion: The present findings suggest that higher total protein intake may not be associated with the risk of colorectal and breast cancer, while conclusions on protein intake in relation to risks of other types of cancer are restricted due to insufficient evidence. [ABSTRACT FROM AUTHOR]

Purpose: Glycemic response to the same meal depends on daytime and alignment of consumption with the inner clock, which has not been examined by individual chronotype yet. This study examined whether the 2-h postprandial and 24-h glycemic response to a meal with high glycemic index (GI) differ when consumed early or late in the day among students with early or late chronotype. Methods: From a screening of 327 students aged 18–25 years, those with early (n = 22) or late (n = 23) chronotype participated in a 7-day randomized controlled cross-over intervention study. After a 3-day observational phase, standardized meals were provided on run-in/washout (days 4 and 6) and intervention (days 5 and 7), on which participants received a high GI meal (GI = 72) in the morning (7 a.m.) or in the evening (8 p.m.). All other meals had a medium GI. Continuous glucose monitoring was used to measure 2-h postprandial and 24-h glycemic responses and their variability. Results: Among students with early chronotype 2-h postprandial glucose responses to the high GI meal were higher in the evening than in the morning (iAUC: 234 (± 92) vs. 195 (± 91) (mmol/L) × min, p = 0.042). Likewise, mean and lowest 2-h postprandial glucose values were higher when the high GI meal was consumed in the evening (p < 0.001; p = 0.017). 24-h glycemic responses were similar irrespective of meal time. Participants with late chronotype consuming a high GI meal in the morning or evening showed similar 2-h postprandial (iAUC: 211 (± 110) vs. 207 (± 95) (mmol/L) × min, p = 0.9) and 24-h glycemic responses at both daytimes. Conclusions: Diurnal differences in response to a high GI meal are confined to those young adults with early chronotype, whilst those with a late chronotype seem vulnerable to both very early and late high GI meals. Registered at clinicaltrials.gov (NCT04298645; 22/01/2020). [ABSTRACT FROM AUTHOR]

Background: The cereal fibre β-glucan reduces postprandial glycaemia, however, the underlying mechanisms are not fully understood. Thus, the aim of this study was to investigate the acute effect of a β-glucan-enriched oat bread on gastric emptying half-time (T1/2), gastric emptying lag phase (Tlag), and gastric emptying rate (GER), and the secretion of glucagon-like peptide-1 (GLP-1) as potential means to influence postprandial glycaemia. Methods: A randomised crossover trial was conducted in 22 healthy adults (age 24.6 ± 3.1 years, BMI 23.1 ± 2.7 kg/m2) receiving 25 g available carbohydrates from a β-glucan-enriched oat bread or a control whole-wheat bread at two non-consecutive days. T1/2, Tlag, and GER were determined based on ultrasound measures of the cross-sectional gastric antrum area in the fasting state and 15, 30, 45, 60, 90, and 120 min postprandially. Capillary glucose, serum insulin, and plasma GLP-1 concentrations were measured at the same time points. Results: A biphasic pattern of gastric emptying with a distinct Tlag before the commencement of emptying was observed in most subjects for both bread types. While no differences in GER were evident (p = 0.562), consumption of the oat bread significantly increased T1/2 by 18 min and Tlag by 14 min compared with the whole-wheat bread (p = 0.005 and p = 0.010, respectively). In addition, the oat bread significantly reduced iAUC2h for glucose and insulin responses compared with the whole-wheat bread (p = 0.001 and p < 0.001, respectively). There were no significant differences in GLP-1 response between the two breads (p = 0.892). Conclusion: The increased T1/2 and Tlag could offer a potential mechanism for the observed attenuation of postprandial glycaemia and insulinemia after consumption of the β-glucan-enriched oat bread compared with the whole-wheat bread. Trial registration: The study is registered at clinicaltrails.gov (NCT04571866). [ABSTRACT FROM AUTHOR]

Background and aims: It is unclear whether socio‐economic status (SES) is associated with glycaemic control in people with recently diagnosed diabetes. The aim was to investigate whether SES is related to haemoglobin A1c (HbA1c) during the first year after diagnosis in people with type 1 and type 2 diabetes and if metabolic, quality of care or mental factors may explain the association. Methods: In the German Diabetes Study, people with type 1 (n = 274, median age 36 [25th; 75th percentile: 28; 48] years) and type 2 diabetes (n = 424, 54 [47; 60] years) underwent detailed metabolic characterisation within the first year after diagnosis. SES was documented using a standardised questionnaire. Associations between SES and HbA1c were assessed using multivariable linear regression and restricted cubic spline regression analyses. Additional covariables were patient characteristics, laboratory measurements, health behaviour, quality of care and depression variables. Models were separately fitted for diabetes type, SES and its dimensions (income, education, occupation). Results: Higher SES score was associated with lower HbA1c (−0.7 mmol/mol per unit increase in SES, 95% CI: −1.1; −0.2 mmol/mol [−0.1%, 95% CI: −0.1; 0.0%]) in people with type 1 diabetes. Included covariates did not attenuate this association. In people with type 2 diabetes, effect estimates were close to zero indicating no relevant difference. Conclusion: Socio‐economic inequalities in HbA1c already exist during the first year after diagnosis in people with type 1 diabetes. The absence of association between glycaemic control and SES in type 2 diabetes could be due to the lower complexity of diabetes therapy compared to type 1 diabetes. [ABSTRACT FROM AUTHOR]

Purpose: Studies about effects of lunch dietary Glycemic Index (GI) on cognition of schoolchildren are scarce. Our previous CogniDo GI study found no changes of cognition in the early postprandial phase after consumption of two rice types with medium vs. high dietary GI for lunch (i.e., 45 min after starting lunch). This study investigated whether the dietary GI of lunch has an impact on cognition of schoolchildren in the late postprandial phase, 90 min after lunch. Methods: A randomized, 2 × 2 crossover intervention study was conducted at a comprehensive school with 5th and 6th grade students. Participants (n = 212) were randomly assigned to either sequence 1 or 2. In the first period, participants of sequence 1 received a dish with high GI rice (GI: 79), those of sequence 2 with medium GI rice (GI: 64)—in the second period, 1 week later, vice versa. Computer-based cognitive testing was performed 90 min after lunch examining tonic alertness, visual search and task switching, and working memory. Treatment effects and treatment effects adjusted for estimated lunch glycemic load (GL) were analyzed using a linear mixed model. Results: The selected cognitive parameters were not affected by the GI of lunch 90 min after lunch, neither after intention-to-treat nor in the per-protocol analysis. Adjustment for GL also did not change results. Conclusion: The present study revealed no notable differences after the consumption of two rice types with medium vs. high dietary GI for lunch in children's cognitive function in the late postprandial phase, 90 min after lunch. Clinical trial registration: German Clinical Trials Register (DRKS00013597); date of registration: 16/04/2018, retrospectively registered. [ABSTRACT FROM AUTHOR]

Purpose: To examine the association between fructose intake in adolescence and fatty liver indices (hepatic steatosis index (HSI), fatty liver index (FLI)) in young adulthood. Methods: Overall, 246 participants of the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) study who had a fasting blood sample in adulthood (18–36 years), at least two 3-day weighed dietary records for calculating fructose intakes and other fructose-containing sugars (total (TS), free (FS), added sugar (AS)) as well as two complete 24-h urine samples for calculating sugar excretion (fructose excretion (FE), fructose + sucrose excretion (FE + SE)) in adolescence (males: 9.5–16.5 years; females: 8.5–15.5 years) were analysed using multivariable linear regression analyses. Results: On the level of dietary intake, no prospective associations were observed between adolescent fructose intake and both adult fatty liver indices, whereas higher FS intakes were associated with lower levels of HSI (Ptrend = 0.02) and FLI (Ptrend = 0.03). On the urinary excretion level, however, a higher FE (Ptrend = 0.03) and FE + SE (Ptrend = 0.01) in adolescence were prospectively related to higher adult FLI values. No associations were observed between adolescent sugar excretion and adult HSI. Conclusion: The present study does not provide unambiguous support for a detrimental impact of adolescent fructose intake on adult liver health. Nonetheless, further examinations estimating exposure by means of urinary excretion as well as dietary intake levels appear warranted. [ABSTRACT FROM AUTHOR]

Background: Application of mixed meal tolerance tests (MMTT) to measure beta-cell function in long-term studies is limited by modification of the commercial products occurring over time. This study assessed the intra-individual reliability of MMTTs and compared the effects of liquid meals differing in macronutrient composition on the estimation of beta-cell function in type 2 diabetes (T2DM). Methods: To test the reliability of MMTTs, 10 people with T2DM (age 58 ± 11 years, body mass index 30.0 ± 4.9 kg/m2) received Boost®high Protein 20 g protein three times. For comparing different meals, another 10 persons with T2DM (58 ± 5 years, 31.9 ± 5.3 kg/m2) ingested either Boost®high Protein 20 g protein or the isocaloric Boost®high Protein 15 g protein containing 35% less protein and 18% more carbohydrates. C-peptide, insulin and glucose release were assessed from the incremental area under the concentration time curve (iAUC) and the intra- and inter-individual variation of these parameters from the coefficients of variations (CV). Results: Repetitive ingestion of one meal revealed intra-individual CVs for the iAUCs of C-peptide, insulin and glucose, which were at least 3-times lower than the inter-individual variation of these parameters (18.2%, 19.7% and 18.9% vs. 74.2%, 70.5% and 207.7%) indicating a good reliability. Ingestion of two different meals resulted in comparable intra-individual CVs of the iAUCs of C-peptide and insulin (16.9%, 20.5%). Conclusion: MMTTs provide reliable estimation of beta-cell function in people with T2DM. Furthermore, moderate differences in the protein and carbohydrate contents in a standardized liquid meal do not result in relevant changes of C-peptide and insulin responses. Trial registration: Clinicaltrials.gov, Identifier number: NCT01055093. Registered 22 January 2010 – Retrospectively registered, https://www.clinicaltrials.gov/ct2/show/study/NCT01055093 [ABSTRACT FROM AUTHOR]

Purpose: Previous studies in older Australians have reported higher alcohol intake in those with low added sugar intake, yet the relationship between energy in liquid form [alcoholic beverages vs. sugar-sweetened beverages (SSB)] and measures of obesity has not been evaluated. We aimed to assess the association between the energy derived from SSB and alcoholic beverages, and to model the association between the substitution of SSB with alcoholic beverages and waist circumference. Methods: In this cross-sectional analysis, dietary data from the Australian Health Survey 2011–12 were analyzed. Participants with implausible dietary intake were excluded by applying the Goldberg cut-off. Usual SSB intake of adults ≥ 19 years old was estimated using the Multiple Source Method and participants were classified into zero-, low- or high-SSB consumers according to their usual SSB intake. Energy from alcoholic beverages in the three SSB consumption groups was compared using multivariable general linear models. A substitution model was used to assess the association between the replacement of SSB with alcoholic beverages and waist circumference. Results: Zero-SSB consumers made up 33% of the included participants. In all age groups, zero-SSB consumers had significantly higher energy intakes from alcoholic beverages than low- and high-SSB consumers. Low- and high-SSB consumers had similar consumption of alcoholic beverages. Substituting SSB intake with alcoholic beverage intake was not associated with significant differences in waist circumference in most age groups. Conclusions: Australian adults who avoid SSB are common but consume substantially more energy in the form of alcoholic beverages. An increase in alcoholic beverage intake could be an 'unintended consequence' of strictly discouraging SSB consumption. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: Despite normal gestational weight gain, dietary studies in pregnant women show intakes below the recommendations for energy and micronutrients. Objective: This study compared changes in dietary intake from the second to third trimester with emphasis on energy intake and carbohydrate quality. Design: These post hoc analyses were based on 566 women participating in the Pregnancy and Glycemic Index Outcomes study, a randomized controlled trial comparing the effect of low-glycemic index (GI) dietary advice with healthy eating advice on selected pregnancy outcomes. With the use of multilevel mixed-regression analysis, changes in total energy intake, starch, sugar, fiber intake, GI, and glycemic load (GL) were correlated with intake of different micronutrients. Results: Energy intake decreased in the third trimester, and most women did not meet the national recommended amounts for iron, folate, and dietary fiber from food sources alone. After adjustment for age, ethnicity, prepregnancy body mass index, and intervention group, change in energy intake was positively related to change in intake of all micronutrients (P < 0.001). GI, GL, and starch intake were inversely related to micronutrient intake (P < 0.001), whereas higher total sugars predicted higher intake (P < 0.001). Associations with dietary fiber were inconsistent. Conclusions: Normal pregnancy can be associated with a decline in energy and micronutrient intake from diet. Low dietary GI and GL were the best predictors of a favorable micronutrient profile. This trial was registered at www.anzctr.org.au as ACTRN12610000174088. [ABSTRACT FROM AUTHOR]

Early life, adiposity rebound, and puberty represent critical growth periods when food choices could have long-term relevance for cancer risk. We aimed to relate dietary patterns during these periods to the growth hormone-insulin-like-growth-factor (GH-IGF) axis, insulin resistance, and body fatness in adulthood. Data from the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study participants with outcome data at 18–37 years, and ≥2 dietary records during early life (1–2 yr;n= 128), adiposity rebound (4–6 years,n= 179), or puberty (girls 9–14, boys 10–15 yr;n= 213) were used. Dietary patterns at these ages were derived by 1) reduced rank regression (RRR) to explain variation in adult IGF-I, IGF-binding protein-3 (IGFBP-3), homoeostasis model assessment for insulin resistance (HOMA-IR) and fat-mass index; 2) principal component analysis (PCA). Regarding RRR, the patterns “cake/canned fruit/cheese & eggs” (early life), “sweets & dairy” (adiposity rebound) and “high-fat foods” (pubertal boys) were independently associated with higher adult HOMA-IR. Furthermore, the patterns “favorable carbohydrate sources” (early life), “snack & convenience foods” (adiposity rebound), and “traditional & convenience carbohydrates” (pubertal boys) were related to adult IGFBP-3 (Ptrend < 0.01). PCA identified “healthy” patterns for all periods, but none was associated with the outcomes (Ptrend > 0.1). In conclusion, dietary patterns during sensitive growth periods may be of long-term relevance for adult insulin resistance and IGFBP-3. [ABSTRACT FROM PUBLISHER]

Nutritive and bioactive components of human milk could be involved in programming metabolic systems that affect bone growth throughout the life course. Bone properties in childhood and adolescence might differ, depending on breastfeeding duration. Thus, breastfeeding could be a relevant factor in the context of primary osteoporosis prevention. The prospective association between breastfeeding duration and bone properties was investigated using the data of 284 participants of the Dortmund Nutritional and Anthropometric Longitudinally Designed Study. Breastfeeding duration was assessed during infancy. Bone properties were measured by peripheral quantitative computed tomography ( pQCT) at ages 5-23 years. Cortical volumetric bone mineral density, cortical bone mineral content, strength strain index, total cross-sectional area of the bone and cross-sectional area of the cortical bone were determined at the 65% site of the radius. Linear regression analyses were performed to check for differences in pQCT parameters of subjects who had not or shortly been breastfed (0-16 weeks) and subjects who had been breastfed for a long duration (≥17 weeks). Multivariable models adjusted for age, gender, forearm length, muscle cross-sectional area, body mass index standard deviation score ( SDS), height SDS and socio-economic status did not yield associations between breastfeeding duration and pQCT parameters. These findings suggest neither protective nor adverse effects of prolonged breastfeeding on bone health in childhood and adolescence. Influences of early nutrition on bone growth might be overridden by current effects of mechanical loads on bone physiology. [ABSTRACT FROM AUTHOR]

Background: Chronic low-grade inflammation is a likely intermediary between quality of carbohydrate and chronic disease risk. Objective: We conducted a systematic literature search to evaluate the relevance of carbohydrate quality on inflammatory markers in observational and intervention studies. Design: MEDLINE, EMBASE, and the Cochrane Library were searched for studies on associations between glycemic index (GI), glycemic load (GL), dietary fiber or fiber supplements or whole grain intake, and high-sensitivity C-reactive protein (hsCRP) or interleukin 6 (IL-6). Included studies had to be conducted on adults (healthy, overweight, with type 2 diabetes or metabolic syndrome features, but without inflammatory disease) with ≥20 participants and a 3-wk duration. Results: In total, 22 of the 60 studies that met our inclusion criteria examined GI/GL: 5 of 9 observational studies reported lower concentrations of hsCRP or IL-6 among persons with a lower dietary GI/GL; 3 of 13 intervention studies showed significant antiinflammatory effects of a low-GI/GL diet, and 4 further studies suggested beneficial effects (trends or effects in a subgroup). For fiber intake, 13 of 16 observational studies reported an inverse relation with hsCRP or IL-6, but only 1 of 11 intervention studies showed a significant antiinflammatory effect of fiber intake, and a further trial reported a beneficial trend. For whole-grain intake, 6 of 7 observational studies observed an inverse association with inflammatory markers, but only 1 of 7 intervention studies reported significant antiinflammatory effects, 1 further study was suggestive (in a subgroup) of such, and another study found an adverse effect (trend only). Conclusions: Evidence from intervention studies for antiinflammatory benefits is less consistent for higher-fiber or whole-grain diets than for low-GI/GL diets. Benefits of higher fiber and whole-grain intakes suggested by observational studies may reflect confounding. [ABSTRACT FROM AUTHOR]

What is already known about this subject? A considerable increase in the prevalence of overweight during the primary school years (7-11 years) has been reported., What this study adds? This reflects lower remission rates of excess body fat (i.e. the proportion of shifts from excess to normal body fat) between the ages of 7 and 11 years as compared with nearly balanced incidence and remission rates of excess body fat between the ages of 3 and 7 years., Objective This study aimed to compare the age-specific balance between incidence and remission of excess body fat between the ages of 3-7 and 7-11 years using the data from a longitudinal study. Design Longitudinal analysis based on the data from the Dortmund Nutritional and Anthropometric Longitudinally Designed ( DONALD) Study, an ongoing, open cohort study in healthy children, conducted in Dortmund, Germany. Excess body fat was defined by the sum of triceps and subscapular skin-fold measurements above the 90th reference percentile of the new German standard; overweight was defined using different national and international standards. The main outcome parameters were incidence and remission rates of excess body fat ( n = 496) and overweight ( n = 518) between the ages of 3 and 7 years and between the ages of 7 and 11 years. Results The incidence rates of excess skin-fold thickness between the ages of 3 and 7 years (4.2 [2.4, 6.2]%) and between the ages of 7 and 11 years (4.3 [2.6, 6.2]%) were almost identical. By contrast, remission rates were significantly lower during the age period of 7-11 years (primary school age) than during the age period of 3-7 years (pre-school age): 37.5 (21.9, 53.1%) compared with 72.3 (59.6, 85.1%). Conclusions These data point to the low remission of excess body fat as an important driving force for the increasing prevalence of excess body fat in children between the ages of 7 and 11 years. Public health initiatives in children should encompass both primary prevention and interventions targeted at children already overweight at school entry. [ABSTRACT FROM AUTHOR]

Background: Low-glycemic index (low-GI) diets may be less nutritious because of limited food choices. Alternately, high-GI diets could be less healthful because of a higher intake of refined carbohydrate. Objective: The objective was to investigate the association between dietary GI, intakes of carbohydrates from high-GI (CHOhigh GI) and low-GI (CHOlow GI) sources, and the risk of nutrient inadequacy in children and adolescents. Design: Children, aged 2-16 y, who provided 2 plausible 24-h recalls in a national survey were included (n = 4140). The ORs of not meeting the Australian Nutrient Reference Values (NRVs) were calculated by logistic regression. Results: Subjects with higher intakes of CHOhigh GI were found to be at risk of not meeting the NRVs for a wide range of nutrients, including calcium and iodine (both P-trend < 0.001). In comparison with subjects in the lowest quartile of CHOhigh GI> those in the highest quartile had 3 times (adjusted OR: 3.13; 95% CI: 2.47, 3.97; P-trend < 0.001) the risk of not meeting the Estimated Average Requirement for calcium. For iodine, the risk increased >5-fold (adjusted OR: 5.45; 95% CI: 3.97, 7.48; P-trend < 0.001). On the other hand, subjects with higher intakes of CHOlow GI were less likely to meet Adequate Intakes of unsaturated fatty acids (all P- trend < 0.001), despite having lower risks of not meeting the NRVs for most nutrients. Conclusion: Children and adolescents who consume more CHOlow GI are more likely to meet most nutrient recommendations than those consuming higher GI diets. [ABSTRACT FROM AUTHOR]