Glycemic index in chronic disease: a review

Do Popular Diets Impact Fertility?

Infertility affects 15% of the population in developed countries, and its prevalence is increasing. Fertility can be influenced by different factors. Although key factors like maternal age cannot be changed, there is growing evidence that other modifiable factors, such as diet, can have an impact on fertility. Diet has become increasingly important in recent years for a number of reasons: the new trend toward a healthy lifestyle, the higher prevalence of certain digestive disorders, a lack of time that leads people to consume more prepared and processed food, and personal choice to not eat meat, among others. To meet these needs, several diets have recently become popular, such as the Mediterranean diet, known as the gold standard of health; the DASH diet, known for preventing hypertension; the Western diet, characterized by processed food; the ketogenic diet, characterized by low carbohydrate intake; and the vegetarian diet, which is the choice for people who do not eat meat or animal by-products. Diets present a unique composition characterized by the presence or absence of specific nutrients, which have also been associated with male and female fertility individually. This review assesses the impact of these diets and of macro- and micronutrients on both female and male fertility.

Quality characteristics of cereal-based foods enriched with different degree of polymerization inulin: A review

Vegetables, cereals and fruit are foods rich in fibre with beneficial and nutritional effects as their consumption reduces the onset of degenerative diseases, especially cardiovascular ones. Among fibres, inulin, oligofructose or fructooligosaccharide (FOS) are the best-studied. Inulin is a generic term to cover all linear β(2-1) fructans, with a variable degree of polymerization. In this review a better understanding of the importance of the degree of polymerization of inulin as a dietary fibre, functions, health benefits, classifications, types and its applications in the food industry was considered in different fortified foods. Inulin has been used to increase the nutritional and healthy properties of the product as a sweetener and as a substitute for fats and carbohydrates, improving the nutritional value and decreasing the glycemic index, with the advantage of not compromising taste and consistency of the product. Bifidogenic and prebiotic effects of inulin have been well established, inulin-type fructans are fermented by the colon to produce short-chain fatty acids, with important local and systemic actions. Addition of inulin with different degrees of polymerization to daily foods for the production of fortified pasta and bread was reviewed, and the impact on sensorial, technological and organoleptic characteristics even of gluten-free bread was also reported.

Association between consumption of sweeteners and endometrial cancer risk: a systematic review and meta-analysis of observational studies

The purpose of this study is to further investigate the relationship between sweetener exposure and the risk of endometrial cancer (EC). Up until December 2022, a literature search in an electronic database was carried out utilizing PubMed, Web of Science, Ovid, and Scopus. The odds ratio (OR) and 95 % confidence interval (CI) were used to evaluate the results. Sweeteners were divided into nutritional sweeteners (generally refers to sugar, such as sucrose and glucose) and non-nutritional sweeteners (generally refers to artificial sweeteners, such saccharin and aspartame). Ten cohort studies and two case-control studies were eventually included. The study found that in 12 studies, compared with the non-exposed group, the incidence rate of EC in the sweetener exposed group was higher (OR = 1·15, 95 % CI = [1·07, 1·24]). Subgroup analysis showed that in 11 studies, the incidence rate of EC in the nutritional sweetener exposed group was higher than that in the non-exposed group (OR = 1·25, 95 % CI = [1·14, 1·38]). In 4 studies, there was no difference in the incidence rate of EC between individuals exposed to non-nutritional sweeteners and those who were not exposed to non-nutritional sweeteners (OR = 0·90, 95 % CI = [0·81, 1·01]). This study reported that the consumption of nutritional sweeteners may increase the risk of EC, whereas there was no significant relationship between the exposure of non-nutritional sweeteners and the incidence of EC. Based on the results of this study, it is recommended to reduce the intake of nutritional sweeteners, but it is uncertain whether use of on-nutritional sweeteners instead of nutritional sweetener.

The Effectiveness of a Low Glycemic Index/Load Diet on Cardiometabolic, Glucometabolic, and Anthropometric Indices in Children with Overweight or Obesity: A Systematic Review and Meta-Analysis

(1) Background: This systematic review and meta-analysis aims to evaluate the impact of a low glycemic index (LGI) and low glycemic load (LGL) diet on children with overweight and obesity, analyzing any changes in anthropometric, cardiometabolic, and glucometabolic parameters. (2) Methods: Three electronic databases (PubMed, Scopus, CENTRAL), as well as clinical trial registries and reference lists of the included studies, were searched for eligible randomized control trials (RCTs). Two independent reviewers performed the screening of the studies, data extraction, and risk of bias assessment. Mean difference (MD) and 95% confidence intervals (CI) using a random effects model were calculated for each outcome. (3) Results: Eleven RCTs (n = 634) examining the effect of LGI diet versus control were identified. The synthesized data provided from the RCTs indicate no difference between intervention and control groups regarding primary outcomes (body weight (MD: -0.14; 95% CI -1.93 to 1.64, 5 trials), body mass index (BMI) (MD: -0.31; 95% CI -0.85 to 0.23, 6 trials), BMI z-score (MD: -0.03; 95% CI -0.09 to 0.02, 5 trials), and waist circumference (MD: -0.52; 95% CI -2.35 to 1.31, 5 trials)) and other measures of cardiometabolic and glucometabolic parameters. The majority of trials were classified as "some concerns". (4) Conclusions: LGI and LGL diets do not seem to be associated with changes in adiposity, cardiometabolic or glucometabolic markers in children with overweight or obesity. Further research comparing the LGI diet to a high glycemic index diet, with proper methodological standards, is required to clarify the benefits of a LGI diet in this population.

Glycemic Index, Glycemic Load, and FAS rs6586161 Polymorphism in Relation to Gastric Cancer Risk: A Case-Control Study in Korea

Many dietary and genetic factors have been confirmed to be associated with gastric cancer risk. This research investigated gastric cancer risk with regard to the glycemic index, glycemic load, and FAS rs6586161 polymorphism. A total of 232 matched pairs were included in this case-control study. Data collection was conducted at two hospitals in Korea from 2002 to 2006. Dietary information was obtained from a food frequency questionnaire, and genotypes of FAS rs6586161 polymorphism were TT, TA, and AA type. Gastric cancer risk was increased for the highest tertile of glycemic index (vs. lowest tertile, OR = 1.84, 95% CI = 1.07-3.18), the highest tertile of glycemic load (vs. lowest tertile, OR = 2.14, 95% CI = 1.23-3.75), and the AA type of FAS rs6586161 polymorphism (vs. TT types, OR = 1.95, 95% CI = 1.13-3.39). Furthermore, gastric cancer risk was significantly elevated for the participants with the highest glycemic load and AA type of FAS rs6586161 polymorphism (vs. the lowest glycemic load and TT type, OR = 5.53, 95% CI = 2.01-15.21). Both the high glycemic load and AA type of FAS rs6586161 polymorphism increased gastric cancer risk; however, the interactions between these two elevated the risk of gastric cancer even more.

One-year nutrition counselling in the context of a Mediterranean diet reduced the dietary inflammatory index in women with breast cancer: a role for the dietary glycemic index

Background: the Mediterranean diet, the low dietary glycemic index (GI) and the dietary inflammation index (DII®) have been associated with lower risk of breast cancer (BC) incidence and mortality. Objective: to investigate whether one-year nutrition counselling in the context of a Mediterranean diet, with or without low-GI carbohydrates counselling, may influence the DII in women with BC. Methods: data were obtained from participants of DEDiCa trial randomized to a Mediterranean diet (MD, n = 112) or a Mediterranean diet with low-GI carbohydrates (MDLGI, n = 111). The diet-derived DII and GI were calculated from 7-day food records while Mediterranean diet adherence from PREDIMED questionnaire. Differences between study arms were evaluated through Fisher's exact test or Mann-Whitney test and associations with multivariable regression analyses. Results: Mediterranean diet adherence significantly increased by 15% in MD and 20% in MDLGI with no difference between arms (p < 0.326). Dietary GI significantly decreased from 55.5 to 52.4 in MD and 55.1 to 47.6 in MDLGI with significant difference between arms (p < 0.001). DII significantly decreased by 28% in MD and 49% in MDLGI with no difference between arms (p < 0.360). Adjusting for energy intake (E-DII) did not change the results. Higher Mediterranean diet adherence and lower dietary GI independently contributed to DII lowering (β-coefficient -0.203, p < 0.001; 0.046, p = 0.003, respectively). Conclusions: DII and E-DII scores decreased significantly after one-year with 4 nutrition counselling sessions on the Mediterranean diet and low GI. Increased adherence to the Mediterranean diet and low GI independently contributed to the DII changes. These results are relevant given that lowering the inflammatory potential of the diet may have implications in cancer prognosis and overall survival.

Effect of Three Bakery Products Formulated with High-Amylose Wheat Flour on Post-Prandial Glycaemia in Healthy Volunteers

Both Glycaemic index (GI) and Glycaemic Load (GL) were introduced to measure the impact of a carbohydrate-containing food on blood glucose. From this perspective, high-amylose (HA) flours, with a higher percentage of resistant starch (RS), may represent a suitable raw material to improve the glycaemic response. The present work aims to investigate the GI of HA bakery products (biscuits, taralli and bread) compared to products obtained from conventional flour. Ten healthy volunteers were enrolled and their capillary blood glucose was measured every 15 min for 2 h after the consumption of HA and control products containing 50 g of available carbohydrates. On average, in the three bakery products, the amount of total starch replaced by RS was equal to 12%. HA biscuits and HA bread showed significantly lower GI than their control counterparts (p = 0.0116 and p = 0.011, respectively) and better glycaemic control. From the survey to assess liking and willingness to pay on HA snacks, HA packages received an average premium of €0.66 compared to control products. Although HA flour results in lower GI in both biscuits and bread, further studies are needed to evaluate the correct composition of HA products to have beneficial effects on post-prandial glycaemia.

Prediction of gastrointestinal cancers in the ONCONUT cohort study: comparison between logistic regression and artificial neural network

Background

Artificial neural networks (ANNs) and logistic regression (LR) are the models of chosen in many medical data classification tasks. Several published articles were based on summarizing the differences and similarities of these models from a technical point of view and critically assessing the quality of the models. The aim of this study was to compare ANN and LR the statistical techniques to predict gastrointestinal cancer in an elderly cohort in Southern Italy (ONCONUT study).

Method

In 1992, ONCONUT was started with the aim of evaluating the relationship between diet and cancer development in a Southern Italian elderly population. Patients with gastrointestinal cancer (ICD-10 from 150.0 to 159.9) were included in the study (n = 3,545).

Results

This cohort was used to train and test the ANN and LR. LR was evaluated separately for macro- and micronutrients, and the accuracy was evaluated based on true positives and true negatives versus the total (97.15%). Then, ANN was trained and the accuracy was evaluated (96.61% for macronutrients and 97.06% for micronutrients). To further investigate the classification capabilities of ANN, k-fold cross-validation and genetic algorithm (GA) were used after balancing the dataset among classes.

Conclusions

Both LR and ANN had high accuracy and similar performance. Both models had the potential to be used as decision clinical support integrated into clinical practice, because in many circumstances, the use of a simple LR model was likely to be adequate for real-world needs, but in others in which there were large amounts of data, the application of advanced analytic tools such as ANNs could be indicated, and the GA optimizer needed to optimize the accuracy of ANN.

Association of nutritional glycaemic indices with global DNA methylation patterns: results from the Moli-sani cohort

BACKGROUND

High dietary glycaemic index (GI) and load (GL) have been associated with increased risk of various cardiometabolic conditions. Among the molecular potential mechanisms underlying this relationship, DNA methylation has been studied, but a direct link between high GI and/or GL of diet and global DNA methylation levels has not been proved yet. We analyzed the associations between GI and GL and global DNA methylation patterns within an Italian population.

RESULTS

Genomic DNA methylation (5mC) and hydroxymethylation (5hmC) levels were measured in 1080 buffy coat samples from participants of the Moli-sani study (mean(SD) = 54.9(11.5) years; 52% women) via ELISA. A 188-item Food Frequency Questionnaire was used to assess food intake and dietary GI and GL for each participant were calculated. Multiple linear regressions were used to investigate the associations between dietary GI and GL and global 5mC and 5hmC levels, as well as the proportion of effect explained by metabolic and inflammatory markers. We found negative associations of GI with both 5mC (β (SE) = - 0.073 (0.027), p = 0.007) and 5hmC (- 0.084 (0.030), p = 0.006), and of GL with 5mC (- 0.14 (0.060), p = 0.014). Circulating biomarkers did not explain the above-mentioned associations. Gender interaction analyses revealed a significant association of the gender-x-GL interaction with 5mC levels, with men showing an inverse association three times as negative as in women (interaction β (SE) = - 0.16 (0.06), p = 0.005).

CONCLUSIONS

Our findings suggest that global DNA methylation and hydroxymethylation patterns represent a biomarker of carbohydrate intake. Based on the differential association of GL with 5mC between men and women, further gender-based separate approaches are warranted.

Low glycaemic index and glycaemic load diets in adults with excess weight: Systematic review and meta-analysis of randomised clinical trials

BACKGROUND

To compare the effects of low and high glycaemic index/glycaemic load (GI/GL) diets on body weight in adults with excess weight.

METHODS

We searched for randomised controlled trials comparing low GI/GL vs. high GI/GL diets from Medline (via PubMed), Embase, Scopus and Web of Science. The variables of interest were anthropometric measurements, fasting glucose and fasting insulin levels and lipid profile, and 10 studies were included in the meta-analysis.

RESULTS

The sample size ranged from 19 to 203 participants. Low GI/GL is not superior to high GI/GL diets on body weight reduction in adults with excess weight (body mass index [BMI] ≥ 25 kg m^-2 ). However, low GI/GL diets show greater body weight reductions in adults with BMI ≥ 30 kg m^-2 (-0.93 kg; 95% confidence interval [CI] = -1.73 to -0.12; p = 0.045). Compared with high GI/GL diets, low GI/GL diets may also help reduce fasting glucose (-1.97 mg dl^-1 ; 95% CI = -3.76 to 0.19; p = 0.030) and fasting insulin (-0.55 µU ml^-1 ; 95% CI = -0.95 to -0.15; p = 0.007). No differences in fat mass, fat-free mass, waist circumference and lipid profile were observed between low GI/GL and high GI/GL diets. The risk of bias for body weight was classified as 'low risk' (25% of the studies) and 'some concerns' for all domains of RoB 2 tool in most studies.

CONCLUSIONS

When compared with high GI/GL diets, low GI/GL diets appear to more effectively reduce fasting glucose and insulin and promote greater body weight reduction in adults with obesity (BMI ≥ 30 kg m^-2 ).

Sri Lankan traditional parboiled rice: A panacea for hyperglycaemia?

The research aimed to scientifically prove that parboiled Sri Lankan traditional rice elicits lower glycaemic responses comparative to raw unpolished or polished rice. Thus the proximate composition and glycaemic indices (GI) of raw, raw polished, and parboiled traditional Sri Lankan rice (Oryza sativa L.) varieties Godaheenati, Batapola el, Dik wee, Dahanala, Unakola samba, and Hangimuththan were studied as comparative data are not available. Cooked parboiled rice contained significantly high moisture (P<0.05) than raw or raw polished. Mineral content was low (<1.5%) regardless of processing. Crude protein was comparatively high (5.8–11.0% DM) with 2.1–5% (DM) fat with raw unpolished and parboiled having higher contents. Digestible starch of raw polished was highest compared to parboiled or raw unpolished (68.8–90.5% DM). Resistant starch was significantly (P<0.05) high in parboiled rice (1.1–7.2%) with the least total dietary fibre in raw polished rice. All varieties of parboiled and raw polished were found to elicit low GI and high GI respectively. High moisture, high resistant starch, and low starch in cooked parboiled rice contributed to low GI compared to raw unpolished or raw polished rice.

Glycemic index, glycemic load, and lung cancer risk: A meta-analysis of cohort and case-control studies

Objective

Glycemic index (GI) or glycemic load (GL) has been investigated in the field of cancer research for several years. However, the relationship between GI or GL and lung cancer risk remains inconsistent. Therefore, this study aimed to summarize previous findings on this relationship.

Methods

PubMed, Embase, Scopus, Web of Science databases, and Cochrane Library were searched by July 2021. This review was conducted in accordance with the PRISMA guidelines. A fixed or random-effects model was adopted for meta-analysis to compute the pooled relative risks (RR) and their corresponding 95% confidence intervals (CIs). Subgroup analyses, sensitivity analyses, and publication bias analyses were also performed.

Results

In total, nine articles were included, with four case-control studies and five cohort studies, including 17,019 cases and 786,479 controls. After merging the studies, pooled multivariable RRs of lung cancer based on the highest versus the lowest intake were 1.14 (95%CI: 1.03–1.26) and 0.93 (95%CI: 0.84–1.02) for GI and GL. Results persisted in most stratifications after stratifying by potential confounders in the relationship between GI and lung cancer risk. There was a non-linear dose response relation for GI with lung caner risk.

Conclusion

GI typically has a positive relationship with lung cancer risk. However, no associations between GL and lung cancer risk were observed based on current evidence, suggesting that this issue should be studied and verified further to substantiate these findings.

Interaction of MC4R rs17782313 variants and dietary carbohydrate quantity and quality on basal metabolic rate and general and central obesity in overweight/obese women: a cross-sectional study

BACKGROUND

Recent studies have shown that dietary carbohydrate quantity and quality as well as genetic variants may contribute to determining the metabolic rate and general and central obesity. This study aimed to examine interactions between melanocortin 4 receptor gene (MC4R) rs17782313 and dietary carbohydrate intake, glycemic index (GI), and glycemic load (GL) on body mass index (BMI), waist circumferences (WC), basal metabolic rate (BMR), and BMR/kg in overweight/obese women.

METHODS

A total of 282 Iranian women (BMI ≥ 25) aged 18-56 years were enrolled in this cross-sectional study. All participants were assessed for blood parameters, body composition, BMR, and dietary intake. Dietary carbohydrate intake, GI, and GL were determined using a valid, reliable 147-item food frequency questionnaire. MC4R rs17782313 was genotyped by the restriction fragment length polymorphism (PCR-RFLP) method.

RESULTS

After adjustment for age and energy intake, significant interactions were observed between carbohydrate intake and MC4R rs17782313 in terms of BMI (P Interaction = 0.007), WC (P Interaction = 0.02), and BMR/kg (P Interaction = 0.003) in this way that higher carbohydrate intake, compared with lower intake, was associated with an increase in BMI and WC for individuals with C allele carriers (TC + CC genotypes), while related to an increase in BMR/kg for those carrying the TT genotype. No significant interaction was found between MC4R rs17782313 and GI and GL on BMI, WC, BMR/kg, and BMR.

CONCLUSIONS

Interactions between the MC4R rs17782313 and carbohydrate intake probably can have an effect on BMI, WC, and BMR/kg in overweight/obese women.

Fruit and vegetable intake and risk of prediabetes and type 2 diabetes: results from a 20-year long prospective cohort study in Swedish men and women

Purpose

To investigate the association between fruit and vegetable intake (FVI) and the risk of developing prediabetes and type 2 diabetes (T2D) in a Swedish prospective cohort study.

Methods

Subjects were 6961 men and women aged 35–56 years old at baseline, participating in the Stockholm Diabetes Prevention Program cohort. By design, the cohort was enriched by 50% with subjects that had family history of diabetes. Anthropometric measurements, oral glucose tolerance tests and questionnaires on lifestyle and dietary factors were carried out at baseline and two follow-up occasions. Cox proportional hazard models were used to estimate hazard ratios with 95% CIs.

Results

During a mean follow-up time of 20 ± 4 years, 1024 subjects developed T2D and 870 prediabetes. After adjustments for confounders, the highest tertile of total FVI was associated with a lower risk of developing T2D in men (HR 0.76, 95% CI 0.60–0.96). There was also an inverse association between total fruit intake and prediabetes risk in men, with the HR for the highest tertile being 0.76 (95% CI 0.58–1.00). As for subtypes, higher intake of apples/pears was inversely associated with T2D risk in both sexes, whereas higher intakes of banana, cabbage and tomato were positively associated with T2D or prediabetes risk in either men or women.

Conclusion

We found an inverse association between higher total FVI and T2D risk and between higher fruit intake and prediabetes risk, in men but not in women. Certain fruit and vegetable subtypes showed varying results and require further investigation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00394-022-02871-6.

Acute Effects of Split Pea-Enriched White Pan Bread on Postprandial Glycemic and Satiety Responses in Healthy Volunteers—A Randomized Crossover Trial

Pulse consumption has been associated with reduced postprandial glucose response (PPGR) and improved satiety. The objective of this study was (i) to investigate the effects of fortifying white pan bread with split yellow pea (Pisum sativum L.) flour on PPGR and appetite-related sensations, and (ii) to determine whether Revtech heat processing of pea flour alters the postprandial effects. A randomized controlled crossover trial was performed with 24 healthy adults. Participants consumed 50 g available carbohydrate from bread containing 20% pea flour that was untreated (USYP), Revtech processed at 140 °C with no steam (RT0%), Revtech processed at 140 °C with 10% steam (RT10%), or a control bread with 100% white wheat flour (100%W). Blood samples were analyzed for glucose and plasma insulin at 0, 15, 30, 45, 60, 90, and 120 min post-meal. Appetite sensations and product acceptability were measured using visual analogue and 9-point hedonic scales. Results showed no significant difference in the postprandial glucose and insulin responses of different bread treatments. However, pea-containing variants resulted in 18% higher fullness and 16–18% lower hunger, desire to eat, and prospective food consumption ratings compared to 100% W. No differences in the aroma, flavor, color, and overall acceptability of different bread products were observed. This trial supports using pea flour as a value-added ingredient to improve the short-term appetite-related sensations of white pan bread without affecting the overall acceptability.

Fruit and vegetable consumption and the risk of type 2 diabetes: a systematic review and dose-response meta-analysis of prospective studies

BACKGROUND

The association between intake of fruit and vegetables and their subtypes, and the risk of type 2 diabetes has been investigated in several studies, but the results have been inconsistent.

OBJECTIVE

We conducted an updated systematic review and dose-response meta-analysis of prospective studies on intakes of fruit and vegetables and fruit and vegetable subtypes and the risk of type 2 diabetes.

DESIGN

PubMed and Embase databases were searched up to 20 October 2020. Prospective cohort studies of fruit and vegetable consumption and type 2 diabetes mellitus were included. Summary relative risks (RRs) and 95% CIs were estimated using a random effects model.

RESULTS

We included 23 cohort studies. The summary RR for high versus low intake and per 200 g/day were 0.93 (95% CI: 0.89 to 0.98, I²=0%, n=10 studies) and 0.98 (95% CI: 0.95 to 1.01, I²=37.8%, n=7) for fruit and vegetables combined, 0.93 (95% CI: 0.90 to 0.97, I²=9.3%, n=20) and 0.96 (95% CI: 0.92 to 1.00, I²=68.4%, n=19) for fruits and 0.95 (95% CI: 0.88 to 1.02, I²=60.4%, n=17) and 0.97 (95% CI: 0.94 to 1.01, I²=39.2%, n=16) for vegetables, respectively. Inverse associations were observed for apples, apples and pears, blueberries, grapefruit and grapes and raisins, while positive associations were observed for intakes of cantaloupe, fruit drinks, fruit juice, brussels sprouts, cauliflower and potatoes, however, most of these associations were based on few studies and need further investigation in additional studies.

CONCLUSIONS

This meta-analysis found a weak inverse association between fruit and vegetable intake and type 2 diabetes risk. There is indication of both inverse and positive associations between intake of several fruit and vegetables subtypes and type 2 diabetes risk, however, further studies are needed before firm conclusions can be made.

Porang (Amorphophallus oncophyllus) Flour Macerated with Strobilanthes crispus Reduced the Blood Glucose Levels of Streptozotocin-Induced Diabetic Rats

BACKGROUND: Diabetes mellitus (DM) is a group of metabolic diseases indicated by hyperglycemia. Dietary regulation represents a viable means of controlling blood glucose levels. Porang (Amorphophallus oncophyllus) is a local tuber that has a low glycemic index due to its high glucomannan content. In combination with Strobilanthes crispus (SC), which is rich in antioxidants, porang flour could be a promising treatment approach for DM. AIM: This study aimed to determine the effect of porang flour macerated with SC on the blood glucose levels of diabetic rats. METHODS: Thirty-five Wistar (Rattus norvegicus) rats were divided into five groups on the basis of their diets: Normal/negative control (NC) group (non-diabetic, standard AIN-93 diet), positive control (PC) group (streptozotocin [STZ]-induced diabetic), glibenclamide (GB) group (STZ-induced diabetic, medicated with GB 100 mg/200 g body weight [BW]), porang (NP) group (modified AIN-93 diet, fiber substituted with 11% porang flour [equal to 1.1 g/200 g BW]), and SC-macerated porang (SP) group (modified AIN-93 diet, fiber substituted with 11% porang flour macerated with SC [equal to 1.1 g/200 g BW]). The rats’ food intakes, stools, and BWs were recorded throughout the study, while their blood glucose levels were measured before the induction of DM, 3 days after the induction of DM, and at the end of the study (14-day treatment period). The data were statistically analyzed using a one-way analysis of variance combined with Duncan’s multiple range test. RESULTS: The rats’ feed intakes during the 14-day treatment period were almost the same, which influenced their BWs. After the induction of DM, the rats’ BWs appeared to decrease, albeit not to a statistically significant extent. This weight loss may have been better controlled in the treatment groups because the glucomannan content of the porang led to an improvement in the rats’ glucose metabolism, especially in the NP and SP groups. The rats’ stools appeared normal in consistency and moisture, and it was confirmed that there were no diarrhea incidents. The glucomannan content also decreased the blood glucose levels in the NP and SP groups. The SP group showed the best results in terms of decreased glucose levels due to the addition of SC as a source of antioxidants. CONCLUSION: Porang exerted an antidiabetic effect that was comparable with the effect of GB (a commercial drug). In combination with SC, it provided a high level of antioxidants. Porang should be further studied to optimize its antidiabetic potency and potential for use as a functional food or nutraceutical.

Dietary glycemic load and its association with glucose metabolism and lipid profile in young adults

BACKGROUND AND AIM

To evaluate the association of Glycemic Load (GL) with glucose metabolism and blood lipids among young adults.

METHODS AND RESULTS

This study included 1538 participants (51% females), evaluated at 21 years of age as part of the EPITeen cohort. The GL of each individual was obtained from the assessment of their dietary intake by using a 86-item semi-quantitative food frequency questionnaire. The evaluation included anthropometric measurements and a fasting blood sample was used to measure glucose, insulin, triglycerides, total cholesterol, high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). Insulin resistance was calculated based on the homeostasis model method (HOMA-IR). The association between the GL and the biochemical parameters was evaluated by linear regression models using β and 95% confidence intervals (95% CI), stratified by sex and adjusted for body mass index (BMI), energy and fiber intake, and self-perceived social class. No association was found between GL and the glucose metabolism parameters after adjustment. Regarding blood lipids, a positive association was found with LDL-C (β = 1.507, 95% CI 0.454; 2.561 for females; β = 0.216, 95% CI -0.587; 1.020 for males) and a negative association with HDL-C (β = -0.647, 95% CI -1.112; -0.181 for females; β = -0.131, 95% CI -0.422; 0.160 for males).

CONCLUSIONS

Our results suggest that, in healthy young subjects, a high GL diet may have a negative impact on lipid profile.

The association between carbohydrate quality index and anthropometry, blood glucose, lipid profile and blood pressure in people with type 1 diabetes mellitus: a cross-sectional study in Iran

BACKGROUND & AIM

Both types and amounts of dietary carbohydrates have always been issues of discussion in diabetes mellitus. Therefore, this study aimed to investigate the association between carbohydrate quality index (CQI) and anthropometry, fasting blood glucose (FBG), lipid profile, systolic (SBP), and diastolic (DBP) blood pressure in adults with type 1 diabetes mellitus (T1DM).

MATERIALS & METHODS

This was a cross-sectional study conducted on 261 adults with T1DM aged 17-36 years who referred to the Iranian Diabetes Association or Diabetes Clinic of Tehran University of Medical Sciences. Dietary data were collected using a 147-item food frequency questionnaire (FFQ). The CQI was calculated from the three indices including dietary fiber, glycemic index (GI), and solid carbohydrates/total carbohydrates ratio. The weight, height, waist circumference, physical activity, HcA1c, SBP, DBP of all participants were measured. Biochemical assessment including serum lipids and FBG levels were analyzed on 81 individuals.

RESULTS

Participants with a higher CQI had a lower body weight, GI, glycemic load, energy, and macronutrient intake (p < 0.05). In addition, after adjustment for age, sex, duration of diabetes, body mass index, physical activity, and energy intake, the lowest level of glycated hemoglobin A1c (HbA1c) was observed in the third tertile of CQI (β = -0.2; SE = 0.1; p-trend = 0.04). No significant association was observed with respect to CQI with FBG, lipid profile, and blood pressure.

CONCLUSION

It was concluded that there was an inverse association between CQI and HbA1c. No significant association was found with respect to CQI with FBG, lipid profile and blood pressure.

Structural factors governing starch digestion and glycemic responses and how they can be modified by enzymatic approaches: A review and a guide

Starch is the most abundant glycemic carbohydrate in the human diet. Consumption of starch-rich food products that elicit high glycemic responses has been linked to the occurrence of noncommunicable diseases such as cardiovascular disease and diabetes mellitus type II. Understanding the structural features that govern starch digestibility is a prerequisite for developing strategies to mitigate any negative health implications it may have. Here, we review the aspects of the fine molecular structure that in native, gelatinized, and gelled/retrograded starch directly impact its digestibility and thus human health. We next provide an informed guidance for lowering its digestibility by using specific enzymes tailoring its molecular and three-dimensional supramolecular structure. We finally discuss in vivo studies of the glycemic responses to enzymatically modified starches and relevant food applications. Overall, structure-digestibility relationships provide opportunities for targeted modification of starch during food production and improving the nutritional profile of starchy foods.

Glycemic index, but not glycemic load, is associated with an increased risk of metabolic syndrome: Meta-analysis of observational studies

BACKGROUND

Diets with high glycemic index (GI) or high glycemic load (GL) have been linked to important risk factors associated with the development of metabolic syndrome (MetS), such as dyslipidemia, higher blood glucose, and insulin concentrations. However, the role of GI and GL in relation to Mets is still understudied and controversial. This review, therefore, assessed whether high GI or GL contribute to development of Mets.

METHODS

A systematic search of four bibliographic databases was conducted (MEDLINE/PubMed, EMBASE, Web of Sciences, and Scopus) from inception to January 2020 for observational studies assessing GI/GL in relation to MetS. Risk estimates were pooled using random-effect models for the highest versus lowest intake categories, and assessed for heterogeneity using subgroup analysis. The dose-response nature of the relationship was also investigated. Sensitivity analysis and Egger test were used to check the robustness of findings and the possibility of publication bias, respectively.

RESULTS

Data from 12 publications (one cohort study and eleven cross-sectional studies) with a total sample size of 36,295 subjects are included. The pooled effect sizes from the nine studies indicated high versus low dietary GI was associated with increased risk of MetS (OR = 1.05, 95% CI: 1.01 to 1.09) (I²  = 58.1, P = .004). This finding was supported by all subgroup analyses except where studies used 24-h recalls for dietary assessment. Additionally, a linear dose-response investigation revealed that each 5-point increment in GI was associated with 2% increase in the risk of MetS (OR = 1.02, 95% CI: 1.01 to 1.02); non-linear pattern was insignificant, however (p-nonlinearity = 0.63). Moreover, pooled effect sizes from ten studies suggested that no association was found between the GL and MetS with results remaining consistent in all subgroup analyses.

CONCLUSION

A diet with lower GI may protect against MetS. Nutrition policy and clinical practices should encourage a diet with low GI. Future studies should include both GI and GL and different criteria of MetS to provide a better comparison.

Rice Compounds with Impact on Diabetes Control

Rice is one of the most cultivated and consumed cereals worldwide. It is composed of starch, which is an important source of diet energy, hypoallergenic proteins, and other bioactive compounds with known nutritional functionalities. Noteworthy is that the rice bran (outer layer of rice grains), a side-stream product of the rice milling process, has a higher content of bioactive compounds than white rice (polished rice grains). Bran functional ingredients such as γ-oryzanol, phytic acid, ferulic acid, γ-aminobutyric acid, tocopherols, and tocotrienols (vitamin E) have been linked to several health benefits. In this study, we reviewed the effects of rice glycemic index, macronutrients, and bioactive compounds on the pathological mechanisms associated with diabetes, identifying the rice compounds potentially exerting protective activities towards disease control. The effects of starch, proteins, and bran bioactive compounds for diabetic control were reviewed and provide important insights about the nutritional quality of rice-based foods.

Dietary glycemic index, glycemic load, insulin index, insulin load and risk of diabetes-related cancers: A systematic review of cohort studies

BACKGROUND & AIMS

It is believed that diets high in glycemic index (GI), glycemic load (GL), Insulin index (II), and Insulin load (IL) are associated with the increased risks of certain cancers through increasing serum glucose or insulin levels.

METHODS

We conducted this systematic review of cohort studies to evaluate the possible relation between GI, GL, II, and IL with diabetes-related cancers, including colorectal, bladder, breast, endometrium, liver, pancreas, and prostate cancers. Two separate investigators conducted a literature search through PubMed/Medline, Scopus, and Web of Science databases up to February 2020, plus reference lists of relevant articles.

RESULTS

Fifty-three cohort studies with a total of 100 098 cancer cases were included in this systematic review. Fifteen out of eighteen studies among breast cancer cases reported no significant association between GI/GL and cancer risk. These numbers were 4 out of 13 for colorectal cancer, 7 out of 9 for endometrial cancer, 2 out of 3 for liver cancer, 8 out of 10 for pancreatic cancer, and 3 out of 3 for prostate cancer. Only one cohort investigated this association in terms of bladder cancer and reported a significant association. Also, five studies reported this relation in terms of II/IL, and only one cohort among endometrial cancer patients observed a significant positive association between the risk of cancer and IL.

CONCLUSION

We concluded a weak association between dietary GI/GL and no association between II/IL with diabetes-related cancer risk. More cohort studies are required to be performed regarding II/IL and the risk of cancer.

A priori dietary patterns and cardiovascular disease incidence in adult population-based studies: a review of recent evidence

Cardiovascular disease (CVD) is the leading cause of death worldwide. Studies using the a priori dietary pattern approach have been criticized for the heterogeneity of their scoring methods. This review aimed to evaluate the evidence on the association between a priori dietary patterns and CVD incidence in recent adult population-based studies. Similar to the conclusions of previous systematic reviews and meta-analyses, our review found that the majority of recent studies suggested that Mediterranean diet (6 out of 10 studies), Dietary Approaches to Stop Hypertension diet (4 out of 6 studies), Dietary Guidelines-based (11 out of 13 studies) patterns, and other emerging dietary patterns, including carbohydrate quality, Dietary Inflammatory Index, Plant-based Diet Index and Healthy Nordic Food Index, were cardioprotective in the general population; however, there was substantial heterogeneity among the studies, possibly due to differences in scoring methods and analytical approaches used and inclusion of different confounders, as well as other methodological drawbacks, such as low numbers of cases and short follow-up periods. Future studies should simultaneously examine and compare multiple a priori dietary patterns in a specific population using a uniform statistical approach. A consensus on the scoring methods for each a priori dietary pattern is also necessary.

Plasma Metabolomic Profiles of Glycemic Index, Glycemic Load, and Carbohydrate Quality Index in the PREDIMED Study

BACKGROUND

The quality of carbohydrate consumed, assessed by the glycemic index (GI), glycemic load (GL), or carbohydrate quality index (CQI), affects the postprandial glycemic and insulinemic responses, which have been implicated in the etiology of several chronic diseases. However, it is unclear whether plasma metabolites involved in different biological pathways could provide functional insights into the role of carbohydrate quality indices in health.

OBJECTIVES

We aimed to identify plasma metabolomic profiles associated with dietary GI, GL, and CQI.

METHODS

The present study is a cross-sectional analysis of 1833 participants with overweight/obesity (mean age = 67 y) from 2 case-cohort studies nested within the PREDIMED (Prevención con Dieta Mediterránea) trial. Data extracted from validated FFQs were used to estimate the GI, GL, and CQI. Plasma concentrations of 385 metabolites were profiled with LC coupled to MS and associations of these metabolites with those indices were assessed with elastic net regression analyses.

RESULTS

A total of 58, 18, and 57 metabolites were selected for GI, GL, and CQI, respectively. Choline, cotinine, γ-butyrobetaine, and 36:3 phosphatidylserine plasmalogen were positively associated with GI and GL, whereas they were negatively associated with CQI. Fructose-glucose-galactose was negatively and positively associated with GI/GL and CQI, respectively. Consistent associations of 21 metabolites with both GI and CQI were found but in opposite directions. Negative associations of kynurenic acid, 22:1 sphingomyelin, and 38:6 phosphatidylethanolamine, as well as positive associations of 32:1 phosphatidylcholine with GI and GL were also observed. Pearson correlation coefficients between GI, GL, and CQI and the metabolomic profiles were 0.30, 0.22, and 0.27, respectively.

CONCLUSIONS

The GI, GL, and CQI were associated with specific metabolomic profiles in a Mediterranean population at high cardiovascular disease risk. Our findings may help in understanding the role of dietary carbohydrate indices in the development of cardiometabolic disorders. This trial was registered at isrctn.com as ISRCTN35739639.

The effect of a low glycaemic index diet on reducing day-long glycaemia in healthy young adults: A randomized crossover trial

AIM

To compare the effect of a low glycaemic index (LGI) diet on reducing day-long glycaemia with a macronutrient-matched high glycaemic index (HGI) diet, using customized meal delivery to ensure compliance.

MATERIALS AND METHODS

We conducted a single-blinded, randomized crossover trial in 14 healthy adults (57% female) with a mean ± SD age of 21.6 ± 1.7 years. A flash glucose monitoring sensor was installed on the subjects on day 1 to capture the interstitial glucose level every 15 minutes for 14 days. Subjects were randomized to receive an LGI (dietary GI = 40) or HGI (dietary GI = 60) diet (three meals and two snacks) from day 2 for 5 consecutive days, followed by a 2-day washout, then switched to the alternative diet for another 5 days. A paired t-test was used to test the differences in the incremental area under the curve (iAUC) of glucose, postprandial glucose (PPG) concentration and maximum postprandial glucose rise (MPGR) between the LGI and HGI periods.

RESULTS

Subjects had lower iAUC for average day-long glycaemia during the LGI intervention period compared with the HGI period (mean ± SD, 865 ± 297 vs. 1024 ± 267 mmol x min/L; P = .047). PPG for breakfast and snack 2, and MPGR for breakfast, snack 2 and dinner, were lower in the LGI period.

CONCLUSIONS

In young healthy adults, following an LGI diet resulted in lower average day-long glycaemia compared with a macronutrient-matched HGI diet. Our results support the use of LGI diets to reduce the risk of developing glucose intolerance.

The formation and in vitro enzymatic digestibility of starch-lipid complexes in steamed bread free from and supplemented with different fatty acids: Effect on textural and retrogradation properties during storage

Herein, the formation of starch-lipid complexes in steamed bread (SBr) free from and supplemented with fatty acids of varying chain lengths, including lauric acid (LA), glycerol monolaurate (GML), stearic acid (SA), and glycerol monostearate (GMS) and their effects on in vitro enzymatic digestibility were investigated. The enthalpy value of SBr samples (1.86-3.46 J/g) was significantly decreased (P < 0.05) compared to wheat starch samples (5.64-7.17 J/g) fortified with fatty acids. The relative crystallinity (16.5%-32.8%) of SBr corresponds to the content of starch-lipid complexes. SBr supplemented with fatty acids exhibited softer texture than lipid-free SBr stored at 4 °C for 0, 1, 4, and 7 days. Higher enzyme resistance was observed in SBr samples supplemented with fatty acids and the content of resistant starch (RS) was increased from 7.54% to 23.13% in SBr supplemented with LA. As demonstrated by microscopic computed tomography (mCT), the crystalline structure of SBr samples supplemented with LA and GML have a higher density than SBr fortified with SA and GMS; the findings which are in line with thermal properties and X-ray diffraction analysis. In sum, the formation of starch-lipid complexes could be considered as a new way to improve the SBr textural features during storage.

Prospective study of a diabetes risk reduction diet and the risk of breast cancer

BACKGROUND

Hyperinsulinemia and higher insulin-like growth factors may increase breast cancer risk. We evaluated a diabetes risk reduction diet (DRRD) and breast cancer risk.

OBJECTIVES

We prospectively evaluated the association between adherence to a DRRD and the incidence of breast cancer.

METHODS

We followed 88,739 women from the Nurses' Health Study (NHS; 1980-2016) and 93,915 women from the NHSII (1991-2017). Incident breast cancer cases (n = 11,943) were confirmed with medical records, and subtypes were determined by tissue microarray data and pathology reports. Information on diet and breast cancer risk factors was repeatedly ascertained in follow-up questionnaires. A DRRD score was derived with 9 factors: lower glycemic index of diet; lower intakes of trans fat, sugar-sweetened beverages/fruit juices, and red/processed meat; higher intakes of cereal fiber, coffee, nuts, and whole fruits; and a higher ratio of polyunsaturated to saturated fat (score range: 9-45). Multivariable-adjusted hazard ratios (MVHRs) and 95% CIs were calculated with Cox proportional hazards models.

RESULTS

Being in the highest compared with the lowest DRRD adherence quintile was associated with a modestly lower breast cancer risk (MVHRQ5vsQ1: 0.89; 95% CI: 0.84, 0.95; P-trend = 0.0002); this was attenuated after adjusting for weight change since age 18 y (MVHRQ5vsQ1: 0.92; 95% CI: 0.87, 0.98; P-trend = 0.01). The inverse association was strongest among women with current BMI < 25 kg/m2 (MVHRQ5vsQ1: 0.89; 95% CI: 0.81, 0.98; P-trend = 0.004; P-interaction = 0.04). Among tumor molecular subtypes, the strongest inverse association was observed with basal-type tumors (MVHRQ5vsQ1: 0.67; 95% CI: 0.45, 1.01; P-trend = 0.04).

CONCLUSIONS

Greater DRRD-adherence was associated with lower breast cancer risk, likely mediated by less weight gain with a DRRD; however, independently of weight change, DRRD-adherence was modestly associated with lower breast cancer risk, particularly among lean women.

Trimethylamine N-oxide: heart of the microbiota-CVD nexus?

We critically review potential involvement of trimethylamine N-oxide (TMAO) as a link between diet, the gut microbiota and CVD. Generated primarily from dietary choline and carnitine by gut bacteria and hepatic flavin-containing mono-oxygenase (FMO) activity, TMAO could promote cardiometabolic disease when chronically elevated. However, control of circulating TMAO is poorly understood, and diet, age, body mass, sex hormones, renal clearance, FMO3 expression and genetic background may explain as little as 25 % of TMAO variance. The basis of elevations with obesity, diabetes, atherosclerosis or CHD is similarly ill-defined, although gut microbiota profiles/remodelling appear critical. Elevated TMAO could promote CVD via inflammation, oxidative stress, scavenger receptor up-regulation, reverse cholesterol transport (RCT) inhibition, and cardiovascular dysfunction. However, concentrations influencing inflammation, scavenger receptors and RCT (≥100 µm) are only achieved in advanced heart failure or chronic kidney disease (CKD), and greatly exceed pathogenicity of <1-5 µm levels implied in some TMAO-CVD associations. There is also evidence that CVD risk is insensitive to TMAO variance beyond these levels in omnivores and vegetarians, and that major TMAO sources are cardioprotective. Assessing available evidence suggests that modest elevations in TMAO (≤10 µm) are a non-pathogenic consequence of diverse risk factors (ageing, obesity, dyslipidaemia, insulin resistance/diabetes, renal dysfunction), indirectly reflecting CVD risk without participating mechanistically. Nonetheless, TMAO may surpass a pathogenic threshold as a consequence of CVD/CKD, secondarily promoting disease progression. TMAO might thus reflect early CVD risk while providing a prognostic biomarker or secondary target in established disease, although mechanistic contributions to CVD await confirmation.

Is there any association between fruit consumption and the risk of gestational diabetes mellitus? A systematic review and meta-analysis

AIM

Although a considerable number of studies have illustrated the positive effects of fresh fruits on metabolic status, the impacts of fruits on the risk of gestational diabetes mellitus (GDM) are inconsistent. In consideration of this issue, we aimed to systematically summarize the findings of cohort studies with respect to the link between fresh fruits and the risk of GDM.

METHOD

We selected cohort studies with English language indexed in PubMed/Medline, Scopus, Web of Science, and Embase from 2000 to 31 January 2018. To examine the link between fresh fruits and the risk of GDM development, relative risk (RR) and 95 % confidence intervals (CIs) for the highest versus the lowest consumption of fruits were pooled using a random effect model and the DerSimonian and Laird method.

RESULTS

Out of 2522 publications, finally 5 cohort studies were obtained. No significant association between fruit consumption and GDM incidence was found (Pooled RR: 0.95; 95 % CI: 0.84, 1.08; I²: 90.3 %, p = 0001). In women who consumed higher amount of fruits before pregnancy, the risk of GDM was 5% lower than in those who consumed lower amount of fruits (0.95; 95 %CI: 0.91, 0.99, I²: 0%, p = 0.85). No link was obtained between fruit consumption during the pregnancy and GDM onset (1.18, 95 % CI: 0.48, 2.91; I²:94.6 %, p = 0.0001).

CONCLUSION

In women who consumed greater fruits before pregnancy, the risk for GDM was 5 % lower than those consumed lower amounts of fruits, while there was no link between fruit consumption throughout the pregnancy and GDM onset. However, due to limited studies and considerable heterogeneity, the findings must be interpreted with great caution.

Glycemic index of millet based food mix and its effect on pre diabetic subjects

Diet plays an important role in management of diabetes and foods having low glycemic index are gaining more importance as they delay the release of glucose in the blood. It is essential to develop low glycemic food mix from regionally available ingredients for use in daily dietaries. Hence, the present study was undertaken to assess the glycemic index of the traditional recipes prepared from developed millet based food mix and their effect on pre diabetic subjects. The developed millet based food mix had appreciable amount of protein (19.41 g/100 g) and dietary fibre (21.11 g/100 g). The traditional recipes viz., roti, dosa and dumpling (mudde) prepared from developed mix exhibited higher acceptance with good sensory parameters and are comparable to regional preparations. The glycemic index was found to be 37, 48 and 53 for dosa, mudde and roti respectively with a glycemic load of 11.05, 18.43 and 18.09. However, all the three developed products showed the relatively lower glycemic index (< 55) and moderate glycemic load of < 20. Further, dietary intervention on pre diabetic subjects revealed that there was a significant reduction in FBS (120.50 ± 18.73 to 97.81 ± 20.00) and HbA1c (6.14 ± 0.30 to 5.67 ± 0.40) indicating their preferable option in the management of diabetes mellitus.

Hypolipidemic and Hypoglycaemic Effect of Wholemeal Bread with Amaranth (Amaranthus dubius Mart. ex Thell.) on Sprague Dawley Rats

The effect of consuming breads made with wheat flour and Amaranth (Amaranthus dubius Mart. ex Thell.) wholemeal flour on Sprague Dawley rats with hyperlipidaemia and hyperglycaemia induced through feeding was studied. Four diets were provided: control (CD: Ratarina^®), commercial bread (CBD), bread with 100 g·kg⁻¹ (ABD10) and 200 g·kg⁻¹ (ABD20) amaranth flour. Zoometric and blood chemistry parameters were measured before and after consuming the diets. A completely random factorial design of 2 × 4 × 2 was used. The factors were blood lipids and glucose level (normal, N and elevated, E), diet (CD, CBD, ABD10 and ABD20) and sex (female, F and male, M). The rats consuming ABD10 and ABD20 diets presented the lowest glucose values, although with no differences (p > 0.05) between the groups of elevated blood lipids and glucose rats (E). Triglyceride concentrations decreased in ABD10 and ABD20 treatments in comparison with CD, elevated blood lipids and glucose (E) rats, while ABD10 rats showed lower total cholesterol level than normal (N) rats. The high-density lipoprotein cholesterol values increased in the ABD10 and ABD20 groups (p < 0.05), while it did lower for very low-density lipoprotein cholesterol and cardiac risk index (p < 0.05). In ABD10 and ABD20 treatments, the abdominal circumference decreased in both sexes (p < 0.05) between weeks 23 and 31. In conclusion, consumption of bread with amaranth improved lipid profiles of rats and could help to prevent metabolic and cardiovascular diseases.

Dietary Carbohydrate Intake, Dietary Glycemic Load and Outcomes of In Vitro Fertilization: Findings from an Observational Italian Cohort Study

In recent decades, increasing attention has been paid to the influence of diet on reproductive health. Carbohydrates in diet affect glucose metabolism and multiple evidences showed the key role of insulin sensitivity in regulating female fertility. We designed a prospective cohort study to investigate the relation between dietary carbohydrate intake, glycemic load (GL) and the outcomes of assisted reproduction. A population of 494 female partners of couples referring to an Italian Fertility Center and eligible for in vitro fertilization (IVF) were enrolled in the study. On the day of the oocyte retrieval, information on their diet was obtained using a validated food frequency questionnaire (FFQ). We calculated the relative risk and 95% confidence interval of embryo transfer, clinical pregnancy and live birth according to the following dietary exposures: GL, glycemic index (GI) as well as the daily carbohydrate and fiber intake. A multiple regression model was used to account for the confounders. After adjusting for age, college degree, body mass index (BMI), leisure physical activity and previous assisted reproduction techniques (ART) cycles, no significant association was observed between the considered dietary exposures and the IVF outcomes. The roles of GL, carbohydrate intake and GI were assessed in strata of the cause of infertility and body mass index and no relation emerged in this further analysis. We found no clear association between the dietary carbohydrate quantity and quality and IVF outcomes in a cohort of infertile Italian women.

Nanotechnology-based approaches for food sensing and packaging applications

The rapid advancement of nanotechnology has provided opportunities for the development of new sensing and food packaging solutions, addressing long-standing challenges in the food sector to extend shelf-life, reduce waste, assess safety and improve the quality of food. Nanomaterials can be used to reinforce mechanical strength, enhance gas barrier properties, increase water repellence, and provide antimicrobial and scavenging activity to food packaging. They can be incorporated in chemical and biological sensors enabling the design of rapid and sensitive devices to assess freshness, and detect allergens, toxins or pathogenic contaminants. This review summarizes recent studies on the use of nanomaterials in the development of: (1) (bio)sensing technologies for detection of nutritional and non-nutritional components, antioxidants, adulterants and toxicants, (2) methods to improve the barrier and mechanical properties of food packaging, and (3) active functional packaging. The environmental, health and safety implications of nanomaterials in the food sector, along with an overview of regulation and consumer perception is also provided.

The advancement of nanotechnology has provided opportunities for the development of new sensing and food packaging solutions, addressing long-standing challenges to extend shelf-life, reduce waste, assess safety and improve the quality of food.

Influence of Whole Wheat Flour Substitution and Sugar Replacement with Natural Sweetener on Nutritional Composition and Glycaemic Properties of Multigrain Bread

Prevalence of diabetes mellitus (DM) is rising globally and largely due to dietary lifestyle changes and urbanization. The concept of glycaemic index (GI) as a dietary tool for the management of DM has been recommended by international health organizations. Whole-grain wheat flour (WWF), ‘acha’ flour (AF), and pigeon pea flour (PPF) were combined in different ratios (80:10:10, 70:15:15, 70:20:10, and 60:20:20) and 100% WWF served as control. Bread was produced from the flour blends using white sugar (sucrose) and/or date palm fruit sugar (DPFS) representing 50 or 100% sugar replacement. Physical attributes, nutritional composition, GIs, and consumer acceptability of the breads were evaluated using standard methods. The multigrain breads had lower values for height, volume, and specific volume, but were most dense than the control [WWF+sugar (WAPC)]. The protein, ash, and crude fibre contents of the breads were significantly improved compared with the control, especially breads containing 100% DPFS, whereas carbohydrate and energy contents were comparable. The breads also contained significant amounts of macro and micro elements and a Na/K ratio of less than 1. Phytate/mineral molar ratios of the bread were lower than the respective critical limits. Multigrain breads showed low GI, especially those with >20% whole wheat substitution and 100% DPFS compared with WAPC, with intermediate GI (65.61) and high glycaemic load (GL). WWF+AF+PPF+DPFS (60:20:20:100) exhibited the highest protein content, a significant fibre content, lowest carbohydrate, GI, GL, and postprandial blood glucose responses, thus may be a suitable dietary guide for sustained health.

Glycemic Index, Glycemic Load and Cancer Risk: An Updated Meta-Analysis

Diets high in glycemic index (GI) and glycemic load (GL) have been related to an increased risk of selected cancers, but additional quantification is required. We updated a systematic review and meta-analysis published in 2015 to May 2019 to provide quantitative information on GI/GL and cancer risk. Relative risks (RR) and the corresponding 95 % confidence intervals (CI) for the highest versus the lowest categories of GI and GL were extracted from selected studies and pooled using random-effects models. Twenty reports (>22,000 cancer cases) have become available after January 2015, and 15 were added to the meta-analyses by cancer sites, which considered a total of 88 investigations. The five additional reports were reviewed, but not included in the meta-analyses, since data were inadequate to be pooled. For hormone-related cancers, summary RRs for the highest versus lowest GI and GL intakes were moderately increased. They ranged from 1.04 (breast) to 1.12 (endometrium) for GI and from 1.03 (prostate) to 1.22 (ovary) for GL, of borderline significance. High GI was associated with small increased risks of colorectal (summary RR for GI: 1.20, 95% CI, 1.07–1.34—GL: 1.09, 95% CI, 0.97–1.22, 19 studies), bladder (GI: 1.25, 95% CI, 1.11–1.41—GL: 1.10, 95% CI, 0.85–1.42, four studies) and kidney cancers (GI: 1.16, 95% CI, 1.02–1.32—GL: 1.14, 95% CI, 0.81–1.60, five studies). GL was not significantly related to those cancer sites. Stomach, prostate and lung cancers were not associated with GI and GL. The present analysis, based on an updated comprehensive evaluation of the epidemiological literature, indicates moderate unfavorable effects of high versus low GI on colorectal, and possibly bladder and kidney cancers, and a possible moderate positive association between GL and endometrial cancer.

Dietary glycemic index, glycemic load, and risk of mortality from all causes and cardiovascular diseases: a systematic review and dose-response meta-analysis of prospective cohort studies

BACKGROUND

Previous findings on the association of dietary glycemic index (GI) and glycemic load (GL) with mortality are conflicting.

OBJECTIVES

The aim of this study was to summarize earlier findings on the association between dietary GI and GL and the risk of cardiovascular disease (CVD) and all-cause mortality.

METHODS

A comprehensive literature search was performed of electronic databases, including MEDLINE (PubMed), Scopus, ISI Web of Science, EMBASE, and Google scholar, up to September 2018. Prospective cohort studies that reported GI and GL as the exposure and all-cause or CVD mortality as the outcome were included in the analysis. The random-effects model was used to estimate pooled RR and 95% CIs of all-cause and CVD mortality.

RESULTS

Eighteen cohort studies with a total of 251,497 participants, reporting 14,774 cases of all-cause mortality and 3658 cases of CVD mortality, were included in the present analysis. No significant association was found between dietary GI and all-cause mortality (RR: 1.07; 95% CI: 0.96, 1.19) and CVD mortality (RR: 1.02; 95% CI: 0.87, 1.20). In addition, dietary GL was not associated with all-cause mortality (RR: 1.08; 95% CI: 0.93, 1.27) or CVD mortality (RR: 1.07; 95% CI: 0.92, 1.25). However, the highest dietary GI, in comparison to the lowest one, significantly increased the risk of all-cause mortality in women (RR: 1.17; 95% CI: 1.02, 1.35). No evidence for a nonlinear association between dietary GI or GL and all-cause and CVD mortality was found (P > 0.05).

CONCLUSIONS

This meta-analysis of prospective cohort studies showed no significant association between either dietary GI or GL and all-cause and CVD mortality in men, but a positive association of GI with all-cause mortality in women.

Carbohydrate quantity and quality affect the risk of endometrial cancer: A systematic review and dose-response meta-analysis

BACKGROUND

Data on the association of dietary intake of total carbohydrates as well as dietary glycemic index (GI) and glycemic load (GL) with risk of endometrial cancer are contradictory. Therefore, we conducted a systematic review and dose-response meta-analysis of observational studies to summarize available findings in this field.

METHODS

The online databases were searched for relevant publications to May 2018 using relevant keywords.

RESULTS

Overall, eight prospective cohort and five case-control studies with a total sample size of 734,765 individuals, aged ≥18 years, and 8466 cases of endometrial cancer were included. Although the overall association between dietary intake of total carbohydrates and risk of endometrial cancer was non-significant, we found a significant positive association in some subgroups of cohort studies including those with ≥10 years' duration of follow-up (combined effect size: 1.29, 95% CI: 1.09-1.53, P = 0.003) and studies with sample size of ≥50,000 participants (combined effect size: 1.24, 95% CI: 1.08-1.43, P = 0.002). In addition, a non-linear dose-response relationship was found in this regard after considering the estimates from cohort studies (P_nonlinearity = 0.002). Combining effect sizes from case-control studies showed a significant positive association between dietary GI and risk of endometrial cancer; such that a-10 unit increase in GI was associated with a 4% greater risk of endometrial cancer (combined effect size: 1.04, 95% CI: 1.02-1.05, P < 0.001). There was also a significant positive association between dietary GL and risk of endometrial cancer in some subgroups of cohort studies and also in non-linear dose-response analysis.

CONCLUSIONS

Although the overall associations of dietary total carbohydrate intake, GI, and GL with risk of endometrial cancer were not significant, there were significant positive associations in some subgroups of the included studies, particularly those with high quality. There was also a dose-response association between dietary total carbohydrate intake, GI and GL, and risk of endometrial cancer.