Association between dietary carbohydrate quality and the prevalence of obesity and hypertension

The association between carbohydrate quality index and headache severity, disability and duration among women with migraine a cross-sectional study

BACKGROUND & AIM

This study aimed to examine the association between Carbohydrate Quality Index (CQI) and headache severity, disability and duration among women with migraine.

MATERIALS & METHODS

In this cross-sectional study, 266 women (aged 18-45 years) were enrolled using a 147-item food frequency questionnaire (FFQ). CQI was defined by four criteria: fiber intake, dietary glycemic index (DGI), whole grains/total grains ratio and solid carbohydrates/total carbohydrates ratio. Anthropometric measurements, visual analogue scale (VAS), migraine disability assessment (MIDAS), and headache duration were assessed for all participants.

RESULTS

Participants with a high adherence to CQI had lower odds of moderate pain (OR = 0.45; 95% CI = 0.21-0.94; P = 0.03) and severe pain (OR = 0.39; 95% CI = 0.18-0.82; P = 0.01) compared to those with a low adherence to CQI. After controlling for potential confounders, individuals with the greatest adherence to CQI showed a 78% reduced prevalence in severe pains and a 63% decreased occurrence in moderate pains compared to those with the lowest adherence (OR = 0.22; 95% CI = 0.09-0.55; P = 0.01 and OR = 0.37; 95% CI = 0.16-0.84; P = 0.01, respectively). Moreover, Subjects with higher adherence to CQI had lower odds of headache duration (OR = 0.54; 95% CI= 0.31-0.96; P = 0.03). The significant association remained (P < 0.05) even after confounding variables (OR = 0.59; 95 % CI = 0.35-1.002; P = 0.05). Despite adjusting for confounding valuables, there was no significant association between the CQI and MIDAS scores (P > 0.05).

CONCLUSION

Higher adherence to CQI was associated with lower severity and duration in patients with migraine. Further studies are needed to confirm these results.

Carbohydrate quality index and risk of non-alcoholic fatty liver disease in Iranian adults

BACKGROUND/AIM

In the current study, we aimed to assess the association of carbohydrate quality index (CQI) with the risk of non-alcoholic fatty liver disease (NAFLD) in Iranian adults.

METHODS

This case-control study was conducted on 225 newly diagnosed NAFLD patients and 450 controls, aged 20-60 years. A food frequency questionnaire was used to calculate the CQI and its components, including fiber intake, glycemic index, whole grains: total grains ratio, and solid carbohydrates: total carbohydrates ratio. Multivariable logistic regression was used to estimate the odds ratio (OR) of NAFLD across the tertile of CQI and its components.

RESULTS

The participant's mean ± SD of body mass index and age were 26.8 ± 4.3 kg/m2 and 38.1 ± 8.8 years, respectively. The median (interquartile) CQI score in participants of the case and control groups was 20 (15-25) and 23 (18-28), respectively. In the multivariable-adjusted model, the risk of NAFLD decreased significantly across the tertiles of the CQI [(OR: 0.20; %95CI: 0.11-0.39), Ptrend <0.001)]. Also, the odds of NAFLD decreased across tertiles of solid carbohydrates to total carbohydrates ratio [(OR: 0.39; 95%CI: 0.22-0.69), Ptrend <0.001)]. However, a high dietary glycemic index (GI) was associated with increased odds of NAFLD [(OR:7.47; 95%CI: 3.89-14.33, Ptrend<0.001)]. There was no significant relationship between other CQI components, including fiber intake and whole grain/total grains and the risk of NAFLD.

CONCLUSIONS

Our results revealed that a diet with a high quality of carbohydrates, characterized by higher intakes of solid carbohydrates, whole grain, and low GI carbohydrates, can be related to a reduced risk of NAFLD.

Quality and quantity of macronutrients, and their joint associations with the incidence of type 2 diabetes over a nine-year follow-up

BACKGROUND

The association between macronutrient consumption and the risk of type 2 diabetes (T2D) remains equivocal. Here, we investigated whether the quantity and quality of macronutrient intake are associated with T2D incidence in a West Asian population.

METHODS

T2D-free adults (n = 2457, mean age 38.5 ± 13.6 years, 54.2% women) who participated in the third examination cycle (2005-2008) of the Tehran Lipid and Glucose Study were followed for a median of 8.6 years. We estimated the macronutrient quality index (MQI), its individual sub-indices (carbohydrate quality index (CQI), fat quality index (FQI), and healthy plate protein quality index (HPPQI)), as well as the macronutrient quantity. The risk of T2D in relation to macronutrient quantity, quality, and their combined effects was examined using Cox proportional hazard models adjusted for known risk factors for T2D.

RESULTS

During the study follow-up, 257 incident cases of T2D were documented. Individuals in the highest tertiles of MQI and CQI had a 27% (HR = 0.73, 95% CI = 0.54, 0.98) and 29% (HR = 0.71, 95% CI = 0.51-0.99) lower T2D risk than those in the lowest tertiles. The T2D incidence was 35% lower in the middle HPPQI tertile than in the lowest (HR = 0.65, 95% CI = 0.47, 0.89). The multivariable adjusted model showed that individuals in the middle and highest tertiles of carbohydrate intake had 32% (HR = 0.68, 95% CI = 0.49-0.95) and 26% (HR = 0.74, 95% CI = 0.55-1.00) lower risks of T2D than individuals in the lowest tertile. A high-quantity, high-quality carbohydrate diet (≥ 58.5% of energy from carbohydrate with a CQI ≥ 13) and a low-glycemic index (GI), high-fiber diet (GI < 55 and fiber ≥ 25 g/d) were related to a reduced risk of T2D by 34% (HR = 0.66, 95% CI = 0.47, 0.93) and 42% (HR = 0.58, 95% CI = 0.38, 0.90), respectively.

CONCLUSION

A diet with a higher carbohydrate quality may be associated with a lower T2D incidence, particularly when the carbohydrate quantity is also high.

Low-Quality Carbohydrate Intake Is Associated With a Higher Prevalence of Metabolic Syndrome: The AWHS Study

CONTEXT

The relationship between carbohydrate quality intake and metabolic syndrome (MetS) is of growing interest.

OBJECTIVE

We aimed to assess the association between the adherence to a dietary carbohydrate quality index (CQI) with the occurrence of MetS in a Spanish cohort of working adults.

METHODS

A cross-sectional study was conducted of 2316 middle-aged men, aged 50.9 (SD 3.9) years, with no previous cardiovascular disease, and pertaining to the Aragon Workers' Health Study (AWHS) cohort. Diet was collected with a 136-item semiquantitative food-frequency questionnaire. The CQI (range 4-15) was based on: dietary fiber intake, a low glycemic index, the ratio of whole grains/total grains, and the ratio of solid carbohydrates/total carbohydrates. The higher the CQI, the healthier the diet. MetS was defined by using the harmonized National Cholesterol Education Programme-Adult Treatment Panel III (NCEP-ATP III) definition. The associations across 3-point categories of the CQI and the presence of MetS were examined using logistic regression.

RESULTS

An inverse and significant association between the CQI and MetS was found. Fully adjusted odds ratios (ORs) for MetS risk among participants in the 10- to 12-point category (second highest CQI category) was 0.64 (95% CI, 0.45-0.94), and in the 13- to 15-point category (highest category) was 0.52 (95% CI, 0.30-0.88), when compared with the 4- to 6-point category (lowest category). Participants with 10 to 12 and 13 to 15 points on the CQI showed a lower risk of hypertriglyceridemia: OR 0.61 (95% CI, 0.46-0.81), and 0.48 (95% CI, 0.32-0.71) respectively.

CONCLUSION

Among middle-aged men, a higher adherence to a high-quality carbohydrate diet is associated with a lower prevalence of MetS. Triglyceridemia is the MetS component that contributed the most to this reduced risk.

Dietary carbohydrate quality index and cardio-metabolic risk factors

Introduction: Improving the quality of diet is known as one of the practical ways to reduce cardio-metabolic risk factors (CMRFs). The carbohydrate quality index (CQI) is a relatively new index to evaluate diet quality. It is calculated based on the ratio of solid carbohydrates to total carbohydrates, dietary fibre intake, glycemic index and the ratio of whole grains to total grains. This systematic review and meta-analysis was designed to investigate the association between dietary CQI and CMRFs. Methods: In this systematic review, some international databases, including Scopus, PubMed, EMBASE, Web of Science, and Google Scholar up to July 2022, were searched according to appropriate keywords. All observational studies with an English full text assessing the association between the dietary CQI and CMRFs were included. Two researchers independently extracted the data and assessed the quality of the articles with the Newcastle-Ottawa Scale. Random/fixed-effect meta-analysis was used to pool standardized mean difference (SMD) as an effect size. Results: 11 studies with a total of 63962 subjects were found to be eligible and included in the qualitative synthesis; only BMI, WC and metabolic syndrome reached the threshold of 3 reports with the same effect size and thus only 5 were included in the meta-analysis. The main finding of the included studies was that there were inverse associations between CQI and CMRFs, mainly obesity, glucose metabolism indices, and blood pressure. In the five studies included in the random effect meta-analysis, the association between CQI and body mass index (SMD: 0.45, 95%CI: -0.12, 1.01), waist circumference (SMD: -0.09, 95%CI: -0.34, 0.15) and metabolic syndrome (SMD: 0.63, 95%CI: -0.01, 1.28) was not statistically significant. Conclusion: Although the qualitative findings support the positive association of CQI with CMRFs, the evidence is insufficient to conclude robust findings. Further observational and interventional studies are needed to clearly elucidate this association.

Association of quality and quantity of macronutrients intake with obesity, new anthropometric indices, lipid accumulation, and blood lipid risk index in Tehranian women

Background

This study examines the association between micronutrient intake, anthropometric indices, lipid accumulation, and blood lipid risk index among Tehranian women.

Methods

A cross-sectional study was conducted on 556 Tehranian women. Dietary intake was measured using a Food Frequency Questionnaire. Biochemical assessment and anthropometric indices were measured, and demographic information and physical activity were collected.

Results

Participants with the highest intake of carbohydrates were more prone to obesity. Conversely, those in the top tertile for protein intake had a lower likelihood of obesity and higher levels of lipid accumulation product (LAP). The highest fat consumers had a 63% decreased chance of having a high Castelli's Risk Index 1 (CRI-1). A higher glycemic index (GI) and glycemic load (GL) were linked to an increased probability of a high atherogenic coefficient (AC). Women in the top tertile of GL were significantly more likely to be obese and had lower odds for high LAP. Participants in the top tertile of aromatic amino acids/branched chain amino acids (AAA/BCAA) had significantly lower chances of high CRI-1 and a high atherogenic index of plasma (AIP). Those in the highest tertile of monounsaturated fatty acids/polyunsaturated fatty acids (MUFA/PUFA) had lower odds of obesity and high AIP.

Conclusions

The amount of carbohydrate (g) and protein intake (%), dietary GL, and the ratio of MUFA to PUFA were associated with obesity. The amount of fat intake (g) and AAA/BCAA indices were associated with CRI-1. LAP decreased with an increase in GL. AC increased with an increase in GI and GL. AAA/BCAA and MUFA/PUFA were associated with AIP.

The association of dietary carbohydrate quality and quantity with obesity among Iranian adolescents: a case-control study

BACKGROUND

Adolescent obesity is considered as a major health concern worldwide which is closely linked to the quality of diet. The purpose of the present study was to assess the carbohydrate quality and quantity in relation to odds of overweight and obesity in adolescents.

METHODS

This case-control study with a 1:1 ratio was conducted on 406 adolescents (14 to 18 years old) matched for age and gender. Participants were selected by multistage cluster random sampling method from March to October 2019 in Shiraz, Iran. Dietary intakes of the study population were assessed by a validated semi-quantitative food frequency questionnaire. Also anthropometric indices were measured using standard methods and demographic information was recorded via face to face interview. The relation between low carbohydrate diet score (LCDS) and carbohydrate quality index (CQI), and odds of obesity was evaluated by multiple Logistic regression.

RESULTS

After adjusting the role of potential confounders, the participants in the third tertiles of LCDS (OR = 0.443, 95% CI = (0.260 to 0.755)) and CQI (OR = 0.005, 95% CI = (0.001 to 0.025)) had less odds of being overweight and obese compared to the first tertile.

CONCLUSION

The present study found an inverse relationship between dietary quantity and quality of carbohydrate intake and the odds of overweight and obesity in a sample of Iranian adolescents.

Macronutrients quality indices and risk of metabolic syndrome and its components in Iranian adults

BACKGROUND/AIM

Evidence from recent studies suggested that the quality of dietary macronutrients can play a possible role in predicting the risk of metabolic disorders. In the current study, we aimed to assess the association of carbohydrate quality index (CQI) and protein score with the risk of metabolic syndrome (MetS) in Iranian adults.

METHODS

This prospective study was conducted within the framework of the Tehran Lipid and Glucose Study on 1738 individuals aged between 40 and 70 years old, who were followed up for a mean of 6.1 years. A food frequency questionnaire was used to determine CQI and protein scores. The multivariable adjusted Cox regression model was used to calculate the hazard ratio (HR) of MetS across quartiles of protein score and CQI, and its components.

RESULTS

The mean ± standard deviation (SD) age and body mass index of the study population (42.5% men) were 49.3 ± 7.5 years and 27.0 ± 4.0 kg/m2, respectively. Mean ± SD scores of CQI and protein for all participants were 12.6 ± 2.4 and 10.3 ± 3.5, respectively. During the study follow-up, 834(48.0%) new cases of MetS were ascertained. In the multivariable-adjusted model, the risk of MetS was decreased across quartiles of CQI (HR = 0.83;95%CI:0.69-1.00, Ptrend=0.025) and protein score (HR = 0.75; 95% CI:0.60-0.94, Ptrend=0.041). Also, Of CQI components, the whole grain/total grains ratio showed a significant inverse association with the risk of MetS (HR = 0.75;95%CI:0.60-0.94, Ptrend=0.012).

CONCLUSION

Our findings revealed that a dietary pattern with higher CQI and protein score may be related to a reduced risk of MetS in adults.

Changes in dietary carbohydrate and lipid quality indices between 2008 and 2018: Analysis of the Brazilian dietary surveys

The aim of the study was to evaluate characteristics and changes over a decade in dietary carbohydrate and lipid quality according to socio-demographic variables. Data was obtained from two Brazilian National Dietary Surveys 2008-2009 (n = 34 003) and 2017-2018 (n = 46 164) examining a nationwide representative sample of individuals ≥10 years old. Food intake was assessed by means of two non-consecutive diet records (2008-2009) and 24 h diet recalls (2017-2018). Carbohydrate Quality Index is a score ranging from 4 to 20 calculated from fibre intake, global dietary glycaemic index, solid/total carbohydrate (CHO) and whole grains/total grains CHO. Lipid Quality Index was estimated by dividing the sum of the dietary content of monounsaturated and polyunsaturated fatty acids by the sum of saturated and trans fatty acids. Indices were categorised into five categories (1 for lowest and 5 for highest quality). Socio-demographic variables were sex, age, income, urban/rural area and place of food consumption. The estimates (95% CI) were generated separately for each survey and then compared to identify changes in time. Our main findings refer to changes in diet quality according to income. At the lowest income level, the proportions of individuals in the best carbohydrate and lipid quality categories reduced from 26.9% to 20.6% and from 30.0% to 24.9%, respectively. Alternatively, at the highest income level, these proportions increased from 22.9% to 26.6% and from 11.9% to 15.7%, respectively. Furthermore, the quality of lipids improved in women and among individuals reporting some away-from-home food consumption, while the quality of carbohydrates was reduced among adolescents and in rural areas.

Carbohydrate quality, fecal microbiota and cardiometabolic health in older adults: a cohort study

The impact of carbohydrate quality, measured by the carbohydrate quality index (CQI), on gut microbiota and health has been scarcely investigated. The aim of this study was to cross-sectionally and longitudinally explore the relationships between CQI, fecal microbiota, and cardiometabolic risk factors in an elderly Mediterranean population at high cardiovascular risk. At baseline and 1-year, CQI was assessed from food frequency questionnaires data, cardiometabolic risk factors were measured, and fecal microbiota profiled from 16S sequencing. Multivariable-adjusted linear regression models were fitted to assess the associations between tertiles of baseline CQI, fecal microbiota, and cardiometabolic risk factors at baseline, and between tertiles of 1-year change in CQI, 1-year change in fecal microbiota and cardiometabolic risk factors. Cross-sectionally, higher CQI was positively associated with Shannon alpha diversity index, and abundance of genera Faecalibacterium and Christensenellaceae R7 group, and negatively associated with the abundance of Odoribacter, and uncultured Rhodospirillales genera. Some of these genera were associated with higher glycated hemoglobin and lower body mass index. In addition, we observed a positive association between CQI, and some pathways related with the metabolism of butyrate precursors and plants-origin molecules. Longitudinally, 1-year improvement in CQI was associated with a concurrent increase in the abundance of genera Butyrivibrio. Increased abundance of this genera was associated with 1-year improvement in insulin status. These observations suggest that a better quality of carbohydrate intake is associated with improved metabolic health, and this improvement could be modulated by greater alpha diversity and abundance of specific genera linked to beneficial metabolic outcomes.

Macronutrient quality and the incidence of metabolically unhealthy phenotypes in adults with normal weight and overweight/obesity

OBJECTIVE

We aimed to investigate the associations of macronutrient quality indices with the incident metabolically unhealthy normal weight (MUNW) and metabolically unhealthy overweight/obesity (MUO) phenotypes.

METHODS

This prospective study included 512 metabolically healthy normal weight and 787 metabolically healthy overweight/obese adults from the third study examination of the Tehran Lipid and Glucose Study. The participants were followed through the sixth study examination. Diet was measured with a food frequency questionnaire. The macronutrient quality index (MQI), carbohydrate quality index (CQI), fat quality index (FQI), and healthy plate quality index (HPPQI) were calculated. Hazard ratio (HR) and 95 % confidence interval (95 % CI) were estimated for incident unhealthy phenotypes using Cox regression.

RESULTS

After controlling all possible confounding factors, a one-point higher HPPQI was linked to a 28 % lower risk of MUNW (HR = 0.72; 95 % CI = 0.59, 0.87). Compared to the lowest quartile, the incident MUNW was also lower in the two last quartiles of the HPPQI. A one-unit increase in MQI was associated with a 5 % lower incident MUO (HR = 0.95; 95 % CI = 0.92, 0.99). The incident MUO was also higher for the highest compared to the lowest MQI quartile. In quartiles 2-4 of the HPPQI, incident MUO was lower with respective HRs (95 % CI) of 0.71 (0.54, 0.93), 0.60 (0.45, 0.80), and 0.66 (0.50, 0.86) in the fully-adjusted model.

CONCLUSIONS

A higher overall macronutrient quality was independently associated with a lower incident MUO. A higher dietary protein quality was related to a lower risk for MUNW and MUO.

Associations between Conventional and Emerging Indicators of Dietary Carbohydrate Quality and New-Onset Type 2 Diabetes Mellitus in Chinese Adults

Dietary glycemic index (GI), carbohydrate to fiber ratio (CF) and carbohydrate quality index (CQI) are conventional and emerging indicators for carbohydrate quality. We aimed to investigate the associations between these indicators and new-onset type 2 diabetes mellitus (T2DM) risk among Chinese adults. This prospective cohort study included 14,590 adults from the China Health and Nutrition Survey without cardiometabolic diseases at baseline. The associations between dietary GI, CF and CQI and T2DM risk were assessed using Cox proportional hazard regression analysis and dose-response relationships were explored using restricted cubic spline and threshold analysis. After a mean follow-up duration of 10 years, a total of 1053 new-onset T2DM cases occurred. There were U-shaped associations between dietary GI and CF and T2DM risk (both P-nonlinear < 0.0001), and T2DM risk was lowest when dietary GI was 72.85 (71.40, 74.05) and CF was 20.55 (17.92, 21.91), respectively (both P-log likelihood ratio < 0.0001). Inverse associations between CQI and T2DM risk specifically existed in participants < 60 y or attended middle school or above (both P-trend < 0.05). These findings indicated that moderate dietary GI and CF range and a higher dietary CQI score may be suggested for T2DM prevention in Chinese adults.

Dietary protein score and carbohydrate quality index with the risk of chronic kidney disease: Findings from a prospective cohort study

BACKGROUND/AIM

This study aimed to examine the associations between dietary protein score and carbohydrate quality index (CQI) and the risk of chronic kidney disease (CKD) in Iranian adults.

METHODS

This population-based cohort study was performed within the Tehran Lipid and Glucose Study framework on 6,044 subjects aged ≥18 years old, who were followed up for a mean of 7.7 years. Dietary protein score and CQI were determined using a food frequency questionnaire. CKD was defined as an estimated glomerular filtration rate <60 ml/min/1.73 m2. A multivariate Cox proportional hazard regression model was used to estimate the risk of CKD across tertiles of protein score and CQI.

RESULTS

The mean (standard deviation) of age and body mass index of participants were 37.9 (12.8) years and 26.8 (4.7) kg/m2, respectively. During the 7.7 ± 2.7 years of follow-up, 1,216 cases (20.1%) of CKD were ascertained. In the final adjusted model, individuals in the highest tertile of protein score had decreased risk of CKD (HR: 0.85, 95% CI: 0.74-0.98, P trend = 0.033). Also, there is a significant association between total carbohydrate score (HR: 0.85, 95% CI: 0.73-0.99, P trend = 0.016), the ratio of whole grain/total grains (HR: 0.81, 95% CI: 0.70-0.94, P trend = 0.004), and glycemic index (HR: 1.30, 95% CI: 1.12-1.51, P trend < 0.001) and risk of CKD. However, no significant association was found between total protein intakes, plant-to-animal ratio, and solid carbohydrate/total carbohydrate with the risk of CKD.

CONCLUSION

Our results revealed a diet with a high protein score and high quality of carbohydrates, characterized by higher intakes of plant proteins, low glycaemic index (GI) carbohydrates, whole grain, fibers, and lower intakes of animal proteins, can be related to reduced CKD risk.

Longitudinal association of dietary carbohydrate quality with visceral fat deposition and other adiposity indicators

BACKGROUND & AIMS

The quality of dietary carbohydrates rather than total carbohydrate intake may determine the accumulation of visceral fat; however, to date, few studies have examined the impact of diet on adiposity using specific imaging techniques. Thus, the aim of this prospective study was to investigate the association between concurrent changes in carbohydrate quality index (CQI) and objectively-quantified adiposity distribution over a year.

METHODS

We analyzed a cohort of 1476 participants aged 55-75 years with overweight/obesity and metabolic syndrome (MetS) from the PREDIMED-Plus randomized controlled trial. Dietary intake information was obtained at baseline, 6- and 12-months from a validated 143-item semi-quantitative food-frequency questionnaire, and CQI (range: 4 to 20) was calculated based on four dietary criteria: total dietary fibre, glycemic index, wholegrain/total grain carbohydrate ratio, and solid/total carbohydrate ratio. Overall and regional adiposity (total body fat, visceral fat and android-to-gynoid fat ratio) was quantified using dual-energy X-ray absorptiometry at all three time points. Multiple adjusted linear mixed-effects models were used to assess associations between concurrent changes in repeatedly measured CQI and adiposity over time.

RESULTS

After controlling for potential confounding factors, a 3-point increment in CQI over 12-month follow-up was associated with a decrease in visceral fat (β -0.067 z-score, 95% CI -0.088; -0.046, p < 0.001), android-to-gynoid fat ratio (-0.038, -0.059; -0.017, p < 0.001), and total fat (-0.064, -0.080; -0.047, p < 0.001). Fibre intake and the ratio of wholegrain/total grain showed the strongest inverse associations with all adiposity indicators.

CONCLUSIONS

In this prospective cohort of older adults with overweight/obesity and MetS, we found that improvements in dietary carbohydrate quality over a year were associated with concurrent favorable changes in visceral and overall fat deposition. These associations were mostly driven by dietary fibre and the wholegrain/total grain ratio.

TRIAL REGISTRATION

The trial was registered at the International Standard Randomized. CONTROLLED TRIAL: (ISRCTN: http://www.isrctn.com/ISRCTN89898870) with number 89898870 and registration date of 24 July 2014, retrospectively registered.

Habitual- and Meal-Specific Carbohydrate Quality Index and Their Relation to Metabolic Syndrome in a Sample of Iranian Adults

Aim

Most studies on diet quality have focused on the habitual and overall intake of foods without considering intakes at specific eating occasions. This study aimed to assess the association between habitual- and meal-specific carbohydrate quality index (CQI) and metabolic syndrome (MetS) in Iranian adults.

Methods

In this cross-sectional study, data from 850 participants were analyzed. Dietary information was obtained from a 3-day nonconsecutive 24 h recall. CQI was calculated from three criteria: dietary fiber, glycemic index, and solid carbohydrate/total carbohydrate ratio. The association between CQI and MetS was assessed by logistic regression.

Results

The prevalences of MetS in the lowest and highest tertile of CQI were 30.1 and 33.7, respectively (P = 0.6). In habitual diet and all the three meals, we failed to find any significant association between tertiles of CQI and MetS either before or after adjustment for covariates. However, in the habitual meals [odds ratio (OR): 0.69, 95% CI: 0.47–0.96] and lunch meals (OR: 0.66; 95% CI: 0.47–0.94), the highest CQI in comparison to the lowest one, significantly decreased the low high-density lipoprotein (HDL). In addition, the trend of low-HDL with CQI in habitual meal and lunch meal was statistically significant.

Conclusion

The results of this study showed that CQI was not associated with MetS and its components. Further investigations into the mechanisms underlying the role of carbohydrate quality in developing metabolic disorders are warranted.

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.

T. Clark C, Shab-Bidar S. Association between carbohydrate quality index and general and central obesity in adults: A population-based study in Iran

Introduction: To determine whether dietary carbohydrates quality index (CQI), glycemic index, and glycemic load is associated with general and abdominal obesity.

Methods: 850 participants, 20 to 59 years old, were enrolled in a cross-sectional study from five Tehran districts through health houses. The 168 items in the semi--quantitative food frequency questionnaire were used to assess dietary intake. The CQI was calculated by using the following four components: glycemic index, total fiber, solid carbohydrate to total carbohydrate ratio, and whole grains: total grains ratio.

Results: After adjusting for confounding factors, the chance of obesity in men (OR=0.38, 95% CI 0.15to 0.95; P =0.04) measured by waist circumference (WC) was significantly lower in the fourth quintile of CQI in comparison with the first quintile. In addition, OR for obesity in men (OR=2.53, 95% CI0.52 to 1.37; P =0.04) was significantly 2.5 times higher among those in the fourth quintile of glycemic index compared with those in the lowest quintile. There was no significant association between dietary carbohydrates with general obesity in men and women.

Conclusion: In summary, dietary CQI is significantly inversely related to central obesity in men,according to this study. Additionally, adherence to a diet with a higher glycemic index in men is positively associated with central obesity.

Lower Interstitial Glucose Concentrations but Higher Glucose Variability during Low-Energy Diet Compared to Regular Diet-An Observational Study in Females with Obesity

This is an observational study of interstitial glucose (IG) concentrations, IG variability and dietary intake under free-living conditions in 46 females with obesity but without diabetes. We used continuous glucose monitoring, open-ended food recording and step monitoring during regular dietary intake followed by a low-energy diet (LED). Thirty-nine participants completed both study periods. The mean BMI at baseline was 43.6 ± 6.2 kg/m2. Three weeks of LED resulted in a mean weight loss of 5.2% with a significant reduction in diurnal IG concentration but with greater glycemic variability observed during LED. The mean 24 h IG concentration decreased from 5.8 ± 0.5 mmol/L during the regular diet period to 5.4 ± 0.5 mmol/L (p < 0.001) during LED, while the mean amplitude of glycemic excursion increased from 1.5 ± 0.7 to 1.7 ± 0.7 mmol/L (p = 0.031). The positive incremental area under the curve at breakfast was significantly larger for LED compared to regular diet. The daily fiber intake and the glycemic index of breakfast meals were significantly associated with the glycemic variability during regular dietary intake. In conclusion, the 24 h mean IG concentration was lower but with more pronounced glycemic variability during LED compared to a regular diet.

Toward an Evidence-Based Definition and Classification of Carbohydrate Food Quality: An Expert Panel Report

Carbohydrate-containing crops provide the bulk of dietary energy worldwide. In addition to their various carbohydrate forms (sugars, starches, fibers) and ratios, these foods may also contain varying amounts and combinations of proteins, fats, vitamins, minerals, phytochemicals, prebiotics, and anti-nutritional factors that may impact diet quality and health. Currently, there is no standardized or unified way to assess the quality of carbohydrate foods for the overall purpose of improving diet quality and health outcomes, creating an urgent need for the development of metrics and tools to better define and classify high-quality carbohydrate foods. The present report is based on a series of expert panel meetings and a scoping review of the literature focused on carbohydrate quality indicators and metrics produced over the last 10 years. The report outlines various approaches to assessing food quality, and proposes next steps and principles for developing improved metrics for assessing carbohydrate food quality. The expert panel concluded that a composite metric based on nutrient profiling methods featuring inputs such as carbohydrate–fiber–sugar ratios, micronutrients, and/or food group classification could provide useful and informative measures for guiding researchers, policymakers, industry, and consumers towards a better understanding of carbohydrate food quality and overall healthier diets. The identification of higher quality carbohydrate foods could improve evidence-based public health policies and programming—such as the 2025–2030 Dietary Guidelines for Americans.

The relationship between dietary patterns and overweight and obesity among adult in Jiangsu Province of China: a structural equation model

Aims

This study aimed to analyze the relationship between diet and overweight and obesity in Jiangsu Province by using structural equation modeling (SEM), and to determine dietary differences between genders in the model.

Methods

Data from 1739 individuals (53.8% female, n = 935) were analyzed. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to classify dietary patterns. SEM and multivariate logistic regression were used to explore the relationship between dietary patterns and overweight and obesity.

Results

Overweight and obesity was found in 49.1%, and no difference was found in gender (51.2% of men and 47.2% of women, respectively; P = 0.090). Three dietary patterns: the traditional dietary pattern (i.e., poultry, light-colored vegetables, red meat and its products, cereals and tubers products, condiment, oils and dark-colored vegetables), the fruit-egg dietary pattern (i.e., fruit, whole grains, pickled vegetables and eggs and eggs products) and nut-wine dietary pattern (i.e., nut, wine and pastry snacks) were established by using EFA and CFA. It was found that the traditional dietary pattern for adult male was positively associated with the overweight and obesity in Jiangsu Province of China through multivariate logistic regression and SEM (OR = 1.954; 95%CI: 1.258 ~ 3.036; β =0.121, P < 0.05, respectively).

Conclusion

The traditional dietary pattern only have positive association with overweight and obesity in men in Jiangsu Province, China.

High-quality intake of carbohydrates is associated with lower prevalence of subclinical atherosclerosis in femoral arteries: The AWHS study

BACKGROUND AND AIMS

High-quality of the carbohydrates consumed, apart from their total amount, appear to protect from cardiovascular disease (CVD). However, the relationship between the quality of carbohydrates and the early appearance of atherosclerosis has not yet been described. Our objective was to estimate the association between the quality of dietary carbohydrates and subclinical atherosclerosis in femoral and carotid arteries.

METHODS

Cross-sectional study of femoral and carotid atherosclerosis assessed using ultrasounds of 2074 middle-aged males, 50.9 (SD 3.9) years old, with no previous CVD, and pertaining to the Aragon Workers' Health Study (AWHS) cohort. Food frequency questionnaires were used to calculate a carbohydrate quality index (CQI) defined as: consumption of dietary fiber, a lower glycemic index, the ratio of whole grains/total grains, and the ratio of solid carbohydrates/total carbohydrates. The presence of plaques across four CQI intervals was studied using adjusted logistic regression models.

RESULTS

The CQI showed a direct inverse association with subclinical atherosclerosis in femoral territories. Participants with a higher consumption of high-quality carbohydrates (13-15 points) were less likely to have femoral plaques when compared with participants in the lowest index interval (4-6 points) (OR = 0.59; 95% CI = 0.39, 0.89; p = 0.005). No association was found between the CQI and the presence of subclinical atherosclerosis in carotid territories. A lower consumption of high-quality carbohydrates tended to be associated with a greater atherosclerosis extension, considered as the odds for having more affected territories (p = 0.011).

CONCLUSIONS

Among middle-aged males, a high-quality intake of carbohydrates is associated with a lower prevalence of femoral artery subclinical atherosclerosis when compared with a lower consumption. Thus, indicating an early relationship between the quality of carbohydrates and the development of CVD.

Caesarean delivery and early childhood caries: Estimation with marginal structural models in Brazilian pre-schoolers

OBJECTIVE

This study analysed the association between caesarean section and early childhood caries (ECC), estimating the effects using regression and causal inference models.

METHODS

This was a historical cohort study of 697 mother-child dyads, conducted in São Luís, Brazil. The caesarean section was the exposure, and the severity of ECC (dmft) was the outcome. Covariates household income, maternal schooling, maternal hypertension, maternal obesity and birth weight were adjusted for in the models. The effects were estimated by Poisson regression (Means Ratio-MR) and causal inference using a marginal structural model (MSM) (MR and Average Treatment Effect-ATE coefficients), weighted by the inverse probability (IPW) of exposure.

RESULTS

Caesarean section was protective against caries in the bivariate (MR 0.81; CI 0.70-0.94; P = 0.005) and multivariate (MR 0.78; CI 0.67-0.91; P = 0.002) models. In MSM analyses, the caesarean section had no effect on ECC (ATE = -0.35; P = 0.107), controlling for IPW of exposure.

CONCLUSION

The apparent association between caesarean section and ECC severity seems spurious, as it did not persist after employing a superior approach to estimating causality.

Comparison of Indices of Carbohydrate Quality and Food Sources of Dietary Fiber on Longitudinal Changes in Waist Circumference in the Framingham Offspring Cohort

The long-term impact of carbohydrate quality on abdominal weight gain is not fully understood. We aimed to examine the prospective relation of a carbohydrate quality index (CQI; defined by four criteria: dietary fiber, glycemic index, whole grain-to-total grain ratio, and solid-to-total carbohydrate ratio), total, cereal grain, vegetable, and fruit fiber, carbohydrate-to-total fiber ratio, and carbohydrate-to-cereal fiber ratio with changes in waist circumference (WC). Subjects were middle-aged to older, mostly white, participants in the Framingham Offspring cohort (n = 3101 subjects), with mean baseline age 54.9 ± 0.2 years (mean ± SE) and body mass index (BMI) 27.2 ± 0.1 kg/m². Food frequency questionnaire (FFQ), health, and lifestyle data were collected approximately every four years over a median total follow-up of 18 years. Repeated measure mixed models were used to estimate adjusted mean change in WC per four-year interval across quartiles of carbohydrate variables. In the most adjusted model, a higher CQI was marginally associated with a smaller increase in WC (2.0 ± 0.1 vs. 2.4 ± 0.1 cm in highest vs. lowest quartile, p-trend = 0.04). Higher ratios of carbohydrate-to-fiber and carbohydrate-to-cereal fiber were associated with greater increases in WC per four-year interval (2.6 ± 0.1 vs. 2.0 ± 0.1 cm, p-trend < 0.001, and 2.5 ± 0.1 vs. 2.1 ± 0.1 cm in highest versus lowest categories, p-trend = 0.007, respectively); whereas higher intake of total fiber (1.8 ± 0.1 vs. 2.7 ± 0.1 cm, p-trend < 0.001), cereal fiber (2.0 ± 0.1 vs. 2.5 ± 0.1 cm, p-trend = 0.001), and fruit fiber (2.0 ± 0.1 vs. 2.7 ± 0.1 cm, p-trend < 0.001) were associated with smaller increases in WC compared to lower intakes. There was a significant interaction between total fiber and total carbohydrate (as % of total energy intake). After stratification, the association between fiber intake and change in WC was not maintained in the context of a high carbohydrate diet. Better carbohydrate quality, primarily higher fiber intake and lower carbohydrate-to-fiber ratios, may help attenuate increases in abdominal adiposity over time.

Relationship between dietary carbohydrate quality index and metabolic syndrome among type 2 diabetes mellitus subjects: a case-control study from Ghana

BACKGROUND

Dietary carbohydrate quality may play an important role in disease development. We evaluated the association between carbohydrate quality index (CQI) and the odds of metabolic syndrome (MetS) in type 2 diabetes mellitus (T2DM) subjects in Ghana.

METHODS

In this case-control study, we analyzed data using 124 T2DM subjects. We obtained dietary information using 2-day 24-h dietary recalls. We calculated CQI from dietary fiber, glycemic index, whole grains/total grains ratio, and solid carbohydrates/total carbohydrates ratio. Serum lipid profiles were measured after an overnight fast of 8-12 h.

RESULTS

Upon adjustments for the effects of covariates, the CQI showed a positive association with high-density lipoprotein cholesterol concentration (beta coefficient (β) = 0.24; standard error (SE) = 0.20; P for trend = 0.01), and an inverse relationship with waist circumference (β = - 17.29; SE = 4.00; P for trend < 0.001), systolic blood pressure (β = - 15.74; SE = 4.69; P for trend < 0.001), diastolic blood pressure (β = - 7.23; SE = 2.97; P for trend = 0.02), and triglyceride concentrations (β = - 0.43; SE = 0.11; P for trend < 0.001). Overall, the CQI had an inverse relationship with the odds of MetS (Odds ratio _{tertile 3 vs.1} 0.05; 95% Confidence interval: 0.01-0.23; p-trend < 0.001). Also, a positive correlation was found between the CQI and fiber, but the CQI showed a negative relationship with dietary glycemic index.

CONCLUSIONS

The present results suggest an inverse association between the CQI of a diet and the odds of MetS. The CQI approach of dietary recommendation may be a useful strategy for dietary carbohydrate selection for the prevention of MetS.

Health benefits of whole grain: effects on dietary carbohydrate quality, the gut microbiome, and consequences of processing

Grains are important sources of carbohydrates in global dietary patterns. The majority of these carbohydrates, especially in refined-grain products, are digestible. Most carbohydrate digestion takes place in the small intestine where monosaccharides (predominantly glucose) are absorbed, delivering energy to the body. However, a considerable part of the carbohydrates, especially in whole grains, is indigestible dietary fibers. These impact gut motility and transit and are useful substrates for the gut microbiota affecting its composition and quality. For the most part, the profile of digestible and indigestible carbohydrates and their complexity determine the nutritional quality of carbohydrates. Whole grains are more complex than refined grains and are promoted as part of a healthy and sustainable diet mainly because the contribution of indigestible carbohydrates, and their co-passenger nutrients, is significantly higher. Higher consumption of whole grain is recommended because it is associated with lower incidence of, and mortality from, CVD, type 2 diabetes, and some cancers. This may be due in part to effects on the gut microbiota. Although processing of cereals during milling and food manufacturing is necessary to make them edible, it also offers the opportunity to still further improve the nutritional quality of whole-grain flours and foods made from them. Changing the composition and availability of grain carbohydrates and phytochemicals during processing may positively affect the gut microbiota and improve health.

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.

Changing Income-Related Inequality in Daily Nutrients Intake: A Longitudinal Analysis from China

Because of economic reform, dietary pattern in China changed rapidly during the past two decades. Meanwhile, the changes of income and nutrients intake had the same trend. This study aims to measure the income-related inequality in daily nutrients intake and its health-related income mobility over time. Data was sourced from four waves of China Health and Nutrition Survey. Concentration indexes and health-related income mobility indexes were employed to measure the income-related inequality of nutrients intake and its change over time. This study found that the daily protein intake, daily fat intake, daily energy intake, and proportion of energy from fat over 30% were more concentrated on the rich, whereas daily carbohydrates intake among the poor. The income-related inequalities were more severe than the cross-sectional perspective in the long run. The dynamic change of urbanisation indexes has resulted that over 30% of energy from fat was more concentrated among the rich and carbohydrates intake among the poor. The nutrition transition may bring about more severe disease economic burden to the poor in the future. This study recommends an approach to minimize gaps between rural and city areas by promoting rural revitalization to reduce the income-related inequality in daily nutrient intake.

Sugar-sweetened beverages consumption in relation to hypertension among Iranian university students: the MEPHASOUS study

PURPOSE

This study aimed to assess the link between sugar-sweetened beverages (SSBs) consumption and hypertension among a large population in the Middle East.

METHODS

In this cross-sectional study (a part of Mental and Physical Health Assessment of University Student: MEPHASOUS study), 66,634 university students from all provinces of Iran, aged ≥ 18 years, were included. A self-administered dietary habits questionnaire was used to assess SSBs consumption as well as other dietary intakes. Participants were categorized based on three levels of SSB consumption: < 1 time/wk, 1-3 times/wk, and ≤ 3 times/wk. Hypertension was defined as systolic blood pressure (SBP) of ≥ 140 and diastolic blood pressure of ≥ 90.

RESULTS

Compared with those in the bottom category, students in the top category of SSBs consumption were more likely to have hypertension (OR 1.71, 95% CI 1.54-1.90). This association remained significant even after adjusting for confounding variables; such that participants in the highest category of SSBs consumption had 2.17 times greater odds of hypertension compared with those in the lowest category (OR 2.17, 95% CI 1.91-2.47). Stratified analysis based on gender and BMI status revealed such significant association in men (OR 2.12, 95% CI 1.79-2.50) and women (OR 2.03, 95% CI 1.67-2.48), and in all categories of BMI including students with underweight (OR 2.53, 95% CI 1.81-3.52), normal-weight (OR 2.13, 95% CI 1.81-2.51), overweight (OR 2.14, 95% CI 1.58-2.89) and obesity (OR 1.59, 95% CI 1.00-2.53).

CONCLUSION

Our results support previous findings indicating a significant positive association between SSBs consumption and hypertension.

LEVEL OF EVIDENCE

Level III, cross-sectional analytic studies.

Secular trends in hypertension and elevated blood pressure among Korean children and adolescents in the Korea National Health and Nutrition Examination Survey 2007-2015

The prevalence of elevated blood pressure (BP) among US children and adolescents has reportedly declined over the past decade. As no Korean data have been analyzed, we aimed to determine recent trends in BP levels among Korean children and adolescents. This study examines data from the Korea National Health and Nutrition Examination Survey segregated into 3 time periods (2007-2009, 2010-2012, and 2013-2015). A total of 7804 Korean children and adolescents aged 10-18 years were included in the analysis. Hypertension (≥95th percentile) and elevated BP (>90th percentile) were defined using the sex-, age-, and height-specific BP standards from 2017 American Academy of Pediatrics guidelines. Mean systolic BP from 2007-2009 to 2013-2015 increased by 3.9 mm Hg, and there was no significant change in diastolic BP. Body mass index (BMI) z-scores significantly increased in the total population from 2007-2009 to 2013-2015. In 2013-2015, the prevalence rates of elevated BP and hypertension were 8.8% and 9.0%, respectively. The prevalence of hypertension in 2013-2015 increased in the total population compared with those in 2007-2009, especially in the obese subgroup, in which the hypertension prevalence was 27.7% in 2013-2015. The prevalence of elevated BP increased during these time period. Associated factors were sex, age, BMI z-score, and survey period for elevated BP; and sex, age, and BMI z-score for hypertension. During our study, mean systolic BP increased, and the prevalence of hypertension in 2013-2015 increased in the pediatric population. A possible influencing factor is obesity, and further long-term data are necessary.

Carbohydrate quality changes and concurrent changes in cardiovascular risk factors: a longitudinal analysis in the PREDIMED-Plus randomized trial

BACKGROUND

Overall quality of dietary carbohydrate intake rather than total carbohydrate intake may determine the risk of cardiovascular disease (CVD).

OBJECTIVE

We examined 6- and 12-mo changes in carbohydrate quality index (CQI) and concurrent changes in several CVD risk factors in a multicenter, randomized, primary-prevention trial (PREDIMED-Plus) based on an intensive weight-loss lifestyle intervention program.

METHODS

Prospective analysis of 5373 overweight/obese Spanish adults (aged 55-75 y) with metabolic syndrome (MetS). Dietary intake information obtained from a validated 143-item semiquantitative food-frequency questionnaire was used to calculate 6- and 12-mo changes in CQI (categorized in quintiles), based on 4 criteria (total dietary fiber intake, glycemic index, whole grain/total grain ratio, and solid carbohydrate/total carbohydrate ratio). The outcomes were changes in intermediate markers of CVD.

RESULTS

During the 12-mo follow-up, the majority of participants improved their CQI by increasing their consumption of fruits, vegetables, legumes, fish, and nuts and decreasing their consumption of refined cereals, added sugars, and sugar-sweetened beverages. After 6 mo, body weight, waist circumference (WC), systolic and diastolic blood pressure (BP), fasting blood glucose, glycated hemoglobin (HbA1c), triglyceride levels, triglycerides and glucose (TyG) index, and TyG-WC decreased across successive quintiles of improvement in the CQI. After 12 mo, improvements were additionally observed for HDL cholesterol and for the ratio of total to HDL cholesterol. Favorable improvements (expressed in common units of SD and 95% CI) for quintile 5 compared with quintile 1 of CQI change were observed for most risk factors, including TyG-WC (SD -0.20; 95% CI -0.26, -0.15), HbA1c (SD -0.16; 95% CI -0.23, -0.10), weight (SD -0.12; 95% CI -0.14, -0.09), systolic BP (SD -0.11; 95% CI -0.19, -0.02) and diastolic BP (SD -0.11; 95% CI -0.19, -0.04).

CONCLUSIONS

Improvements in CQI were strongly associated with concurrent favorable CVD risk factor changes maintained over time in overweight/obese adults with MetS. This trial was registered as ISRCTN 89898870.

Perspective: The Application of A Priori Diet Quality Scores to Cardiovascular Disease Risk-A Critical Evaluation of Current Scoring Systems

Healthy dietary habits are the cornerstone of cardiovascular disease (CVD) prevention. Numerous researchers have developed diet quality indices to help evaluate and compare diet quality across and within various populations. The availability of these new indices raises questions regarding the best selection relevant to a given population. In this perspective, we critically evaluate a priori-defined dietary indices commonly applied in epidemiological studies of CVD risk and mortality. A systematic literature search identified 59 observational studies that applied a priori-defined diet quality indices to CVD risk factors and/or CVD incidence and/or CVD mortality. Among 31 different indices, these scores were categorized as follows: 1) those based on country-specific dietary patterns, 2) those adapted from distinct dietary guidelines, and 3) novel scores specific to key diet-related factors associated with CVD risk. The strengths and limitations of these indices are described according to index components, calculation methods, and the application of these indices to different population groups. Also, the importance of identifying methodological challenges faced by researchers when applying an index are considered, such as selection and weighting of food groups within a score, since food groups are not necessarily equivalent in their associations with CVD. The lack of absolute cutoff values, emphasis on increasing healthy food without limiting unhealthy food intake, and absence of validation of scores with biomarkers or other objective diet assessment methods further complicate decisions regarding the best indices to use. Future research should address these limitations, consider cross-cultural and other differences between population groups, and identify translational challenges inherent in attempting to apply a relevant diet quality index for use in CVD prevention at a population level.

Association between Carbohydrate Quality Index and general and abdominal obesity in women: a cross-sectional study from Ghana

OBJECTIVES

The relationships between carbohydrate intake and risk of obesity have been widely investigated. However, there are limited data on the associations between their relative proportions and quality contained in the same diet on risk of obesity, especially in low-income and middle-income countries. The aim of this study was to assess the relationship between an overall Carbohydrate Quality Index (CQI) and general and abdominal obesity in women.

SETTING AND PARTICIPANTS

In this cross-sectional study, data from 277 women in Ghana were analysed. Dietary information was obtained from 2-day 24 hours dietary recalls. CQI was calculated from the four indices dietary fibre, Glycaemic Index, whole grains/total grains ratio and solid carbohydrates/total carbohydrates ratio.

OUTCOME MEASURES

Body mass index, waist circumference (WC), waist-to-height ratio (WHtR) and Conicity Index were measured.

RESULTS

After adjusting for covariates, the chance for general obesity (OR 0.25, 95% CI 0.10 to 0.65) and abdominal obesity measured by WC (OR 0.22, 95% CI 0.08 to 0.58) were significantly lower in the topmost quintile of CQI in comparison with the lowest quintile. In addition, the OR for higher WHtR (OR 0.27, 95% CI 0.11 to 0.69) was significantly lower among participants in the fifth quintile of CQI compared with those in the first quintile.

CONCLUSIONS

The present study demonstrates that there is an inverse association between dietary CQI and both general and abdominal obesity. These findings suggest that CQI may be used for the improvement of dietary intake to prevent obesity.

The association between glycemic index, glycemic load, and metabolic syndrome: a systematic review and dose-response meta-analysis of observational studies

PURPOSE

The association of glycemic index (GI) and glycemic load (GL) with metabolic syndrome (MetS) is controversial. Therefore, we conducted this first systematic review and dose-response meta-analysis of observational studies to quantify these associations.

METHODS

We searched PubMed, EMBASE, Web of Science, and the Cochrane Library for relevant studies up to 1 April 2019. Summary odds ratios (OR) and 95% confidence intervals (CI) were calculated by a random-effects model. This study was registered with PROSPERO (CRD42019131788).

RESULTS

We included eight high-quality (n = 5) or medium-quality (n = 3) cross-sectional studies in the final meta-analysis, comprising 6058 MetS events and 28,998 participants. The summary ORs of MetS for the highest versus lowest categories were 1.23 (95% CI 1.10-1.38, I² = 0, tau² = 0, n = 5) for dietary GI, 1.06 (95% CI 0.89-1.25, I² = 36.2%, tau² = 0.0151, n = 6) for dietary GL. The summary OR was 1.12 (95% CI 1.00-1.26, I² = 0, tau² = 0, n = 3) per 5 GI units, 0.96 (95% CI 0.83-1.10, I² = 33.4%, tau² = 0.0059, n = 2) per 20 GL units.

CONCLUSIONS

Dietary GI was positively associated with the prevalence of MetS. However, no significant association was found between dietary GL and the prevalence of MetS. Further studies with prospective design are needed to establish potential causal relationship between dietary GI and the MetS.

Association between quality and quantity of dietary carbohydrate and pregnancy-induced hypertension: A case-control study

BACKGROUND & AIMS

Pregnancy-induced hypertension (PIH) is a pregnancy-specific disorder that increases maternal and infant mortality and morbidity. The quantity and quality of consumed carbohydrates are probably the main dietary factors affecting blood pressure. The present study aimed to evaluate the association of carbohydrate quality and quantity with PIH.

METHODS

This case-control study was performed on 202 pregnant women with or without PIH. The dietary data were collected using 168-item semi-quantitative food frequency questionnaires. Daily glycemic index (GI) and glycemic load (GL), ratio of whole grains to total grains, ratio of solid carbohydrates to total carbohydrates, dietary fiber and carbohydrate intake, and carbohydrate quality index (CQI) were calculated and their associations with PIH were evaluated using logistic regression. We eliminated collinearity within independent variables using factor analysis and then with evaluating the relationship between extracted factors and PIH.

RESULTS

In pregnant women in whom the daily carbohydrate intake and GL were higher than median increased frequency of PIH compared to whom had lower than median ones (OR = 3.23, 95% CI 1.46-7.17, and P = 0.004; OR = 2.60, 95% CI 1.21-5.56; and P = 0.035, respectively). Furthermore, we showed a significant inverse association between extracted factor that was mostly related to total fiber intake frequency of PIH (OR = 0.45; 95% CI 0.20-0.97, and P = 0.049 when higher than median values compared to lower than ones). The GI, ratio of whole grains to total grains, ratio of solid carbohydrates to total carbohydrates, and CQI did not associate with PIH.

CONCLUSIONS

These findings suggest that carbohydrate intake and GL are related to higher and daily fiber intake to lower frequency of PIH.