Association of postoperative dietary macronutrient content and quality with total weight loss and fat-free mass loss at midterm after sleeve gastrectomy

OBJECTIVES

This study aimed to investigate the associations of macronutrient quantities and qualities with percentage total weight loss and percentage of fat-free mass loss relative to total weight loss in adults undergoing sleeve gastrectomy.

METHODS

This cross-sectional study included 146 patients on postoperative time since sleeve gastrectomy of 2 to 4 y. Diet was assessed using a food frequency questionnaire. Macronutrient quality index, carbohydrate quality index, fat quality index, and healthy plate protein quality index were calculated. The associations of dietary variables with percentage total weight loss and percentage of fat-free mass loss relative to total weight loss were determined using linear regression. Logistic regression was used to estimate the odds of non-response (percentage total weight loss < 25%) and excessive fat-free mass loss (percentage of fat-free mass loss relative to total weight loss > 28%) based on dietary intakes.

RESULTS

Forty-six (31.5%) were non-responders, and 49 (33.6%) experienced excessive fat-free mass loss. The fully adjusted model showed a 0.75 decrease in percentage total weight loss per 5% carbohydrate increase (95% CI, -1.45 to -0.05). The odds of non-response were 53% lower per 5% increase in protein (95% CI, 0.23-0.94). Each 5-g higher intake of fat was associated with 0.29 higher percentage of fat-free mass loss relative to total weight loss (95% CI, 0.03-0.55). The odds of excessive fat-free mass loss were reduced by 5% per gram of fiber intake (95% CI, 0.90-0.99). Each 5% increment in energy intake from protein that was isocalorically substituted for either carbohydrate or fat was associated with lower odds of nonresponse. Macronutrient quality indices had no significant associations.

CONCLUSIONS

Adherence to a high-protein, high-fiber diet after sleeve gastrectomy may enhance surgical success by improving total weight loss and preventing excessive fat-free mass loss.

Carbohydrate quality, not quantity, linked to reduced colorectal cancer incidence and mortality in US populations: evidence from a prospective study

BACKGROUND

Carbohydrates have been implicated in colorectal cancer (CRC) risk, but the specific impact of carbohydrate quality and quantity on CRC susceptibility in US populations remains unclear.

METHODS

We followed 101,694 participants from Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. The carbohydrate quality index (CQI) and low-carbohydrate diet score (LCDs) were used to evaluate the daily carbohydrate quality and quantity separately, where higher scores indicated greater adherence. Cox proportional hazards regression was used to compute HRs and 95% CIs for incident CRC and related death. Subgroup analyses were conducted to identify potential effect modifiers.

RESULTS

During follow-up, we documented 1085 incident cases of CRC, of whom 311 died from CRC. Individuals in the highest compared with the lowest quartiles of CQI had a lower CRC incidence (Q4 vs Q1: HR 0.80, 95% CI 0.67-0.96, Ptrend = 0.012) and mortality (Q4 vs Q1: HR 0.61, 95% CI 0.44-0.86, Ptrend = 0.004). The inverse association between CQI and CRC risk was observed for distal colon and rectum but not for proximal colon cancer. Regarding mortality, this association was only significant for rectum cancer. Subgroup analyses indicated this inverse association of CQI with CRC risk was only observed in participants with lower LCDs. No significant associations were found between LCDs and CRC incidence or mortality.

CONCLUSIONS

Our findings suggest focusing on higher quality, rather than restricting the quantity, of carbohydrate consumption may be an effective approach to reduce the risk of CRC in the US population, particularly for distal colon and rectal cancers.

Preoperative Carbohydrate Quality Index Is Related to Markers of Glucose Metabolism 12 Months After Roux-en-Y Gastric Bypass

OBJECTIVE

The role of carbohydrates in weight loss in patients undergoing bariatric surgery (BS) remains poorly understood. Therefore, this study aimed to verify the relationship of the carbohydrate quality index (CQI) with weight loss and cardiometabolic risk markers up to 1 year after BS.

MATERIAL AND METHODS

This study included 50 patients with obesity undergoing Roux-en-Y gastric bypass. Data collection was performed preoperatively and 3 and 12 months after surgery. The foods consumed were documented using a 24-h food recall in 3 days. The CQI was calculated considering the following parameters: dietary fiber intake, sugar level; whole grains: proportion of total grains; solid carbohydrate: total carbohydrate ratio.

RESULTS

From the total study sample, 58 participants were followed up for 3 months, and eight participants dropped out of the study. The remaining 50 patients were followed up for 12 months. Subjects were classified into tertiles according to the index score. A 1-unit increase in CQI was associated with a -1.02 decrease in insulin concentrations at 12 months and a -1.04 decrease in HOMA-IR. Concerning the total sample, the median of the CQI was 8 points and did not change at 3 and 12 months after surgery, but there was an improvement in some components of the index.

CONCLUSION

The data suggest that the quality of carbohydrates can interfere with markers of insulin resistance after BS and the quality of carbohydrates is a point to be guided in patients undergoing BS.

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.

Dietary carbohydrate quality index (CQI), cardio-metabolic risk factors and insulin resistance among adults with obesity

BACKGROUND

Metabolic syndrome (MetS), as a cluster of cardiometabolic risk factors, is a global public health concern due to its increasing prevalence. Considering the previous evidence of the association between carbohydrate quality and cardiometabolic risk factors, our study was aimed to evaluate any possible association between carbohydrate quality index (CQI) and cardiometabolic risk factors among obese adults.

METHODS

In this cross-sectional study, 336 apparently healthy individuals with obesity were participated. Dietary intake was assessed by a semi-quantitative Food Frequency Questionnaire (FFQ), including 168 food items validated for the Iranian population. CQI was calculated with three components of solid carbohydrates to total carbohydrates ratio, dietary fiber intake, and dietary glycemic index (GI). Body composition was determined by bioelectrical impedance analysis (BIA). Blood pressure was measured by sphygmomanometer and enzymatic methods were used to evaluate serum lipid, glucose, and insulin concentrations.

RESULTS

Subjects in the third quartile of CQI had significantly lower systolic blood pressure (SBP) (P = 0.03) and diastolic blood pressure (DBP) (P = 0.01). Participants in the higher quartiles of CQI had more intake of energy, carbohydrates, fat, saturated fatty acid (SFA), and mono-saturated fatty acid (MUFA) (P < 0.05). Moreover, the homeostasis model assessment of insulin resistance (HOMA-IR) was decreased in the second quartile of CQI [odds ratio (OR) = 0.146, P = 0.01) after adjustment for age, body mass index (BMI), sex, physical activity, socioeconomic status (SES) and energy intake.

CONCLUSION

According to our findings, a higher quality of dietary carbohydrates, determined by CQI, could be associated with a lower risk of hypertension.

Carbohydrate quality indices and colorectal cancer risk: a case-control study

BACKGROUND

Colorectal cancer (CRC) is the fourth and third most common cancer in Iran and the world, respectively. Carbohydrates can lead to the proliferation of cancer cells, including CRC. The current study aimed to investigate the association between glycemic load (GL), insulin load (IL), glycemic index (GI), insulin index (II), low-carbohydrate diet score (LCDS), and carbohydrate quality index (CQI) with CRC odds.

METHODS

The present case-control study was performed on 71 CRC cases and 142 controls in the Hospital Cancer Organization and three general hospitals in Tehran, Iran. We calculated the dietary GI, GL, IL, II, CQI, and LCDS by a validated food frequency questionnaire.

RESULTS

The results indicated that people who were in the highest tertile of the GI had higher odds of CRC compared to the lower tertile (in the adjusted model: odds ratio (OR) = 3.89; 95% confidence interval (CI): 1.71-8.84). On the contrary, people who were in the highest tertile of the CQI and LCDS had significantly lower odds of CRC compared to the lower tertile (in the adjusted model: tertile (T) ₂-OR = 0.24; 95% CI: 0.11-0.53 and T₃-OR = 0.15; 95% CI: 0.06-0.39 for CQI and T₂-OR = 0.33; 95% CI: 0.13-0.79 and T₃-OR = 0.28; 95% CI: 0.10-0.82 for LCDS). Also, IL was positively associated with the odds of CRC after adjusting for confounding factors (T₂-OR = 2.46; CI: 1.08-5.61 and T₃- OR = 2.80; 95% CI: 1.07-7.31). Regarding the GL, only individuals who were in the second tertile had significantly higher odds of CRC compared to the first tertile (OR = 2.42; CI: 1.07-5.47).

CONCLUSION

According to the findings, it is recommended to use a diet with high-quality carbohydrates and low GI and GL to minimize the odds of developing CRC. People should also be encouraged to have a balanced carbohydrate intake.

How do carbohydrate quality indices influence on bone mass density in postmenopausal women? A case-control study

BACKGROUND

Carbohydrates are the primary energy source in Asian countries, including Iran. An emerging method can be used to measure the quality of carbohydrates, including the carbohydrate quality index (CQI), which includes a variety of components. Low-carbohydrate diet score (LCDS) has been proposed as a new method of scoring micronutrient intake that could provide a reasonable explanation for the link between diet and the risk of chronic diseases.

OBJECTIVE

This study aimed to investigate the relationship between CQI, LCDS, glycemic index (GI), glycemic load (GL), insulin load (IL), and insulin index (II) with bone mass density (BMD) in postmenopausal women.

METHOD

In this case-control study, 131 postmenopausal women with osteoporosis/osteopenia and 131 healthy postmenopausal women aged 45-65 participated. The dual-energy X-ray absorptiometry (DEXA) method measured the BMD of the lumbar vertebrae and femoral neck. A validated semi-quantitative food frequency questionnaire was used to assess dietary intake. Logistic regression were used to evaluate the relation between GI, GL, II, IL, CQI, and LCDS with BMD.

RESULTS

Diets with higher GI increased the risk of osteopenia and osteoporosis, but LCDS and CQI decreased the risk of osteopenia and osteoporosis.

CONCLUSION

These findings suggest that a higher intake of fruits and vegetables and receiving various dietary vitamins, minerals, and antioxidant compounds may be a useful way to prevent osteopenia in Iranian women.

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.

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.

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.

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.

Association of carbohydrate quality and all-cause mortality in the SUN Project: A prospective cohort study

BACKGROUND & AIMS

Emerging evidence supports shifting the focus from carbohydrate quantity to carbohydrate quality to obtain greater health benefits. We investigated the association of carbohydrate quality with all-cause mortality using a single, multidimensional carbohydrate quality index (CQI) designed to account for multiple characteristics of carbohydrate quality.

METHODS

A prospective study was conducted among 19,083 participants in the Seguimiento Universidad de Navarra (SUN) Project, a Mediterranean cohort of middle-aged university graduates. The CQI was based on four dimensions: high total dietary fiber intake, low glycemic index, high whole-grain carbohydrate: total grain carbohydrate ratio, and high solid carbohydrate: total carbohydrate ratio.

RESULTS

During 12.2 years of median follow-up, 440 deaths were identified. We found an inverse association between the CQI and all-cause mortality. The multivariable-adjusted hazard ratio (HR) for the highest vs. the lowest tertile of the CQI was 0.70 (95% CI, 0.53-0.93; P_trend = 0.018). However, each individual dimension of the CQI was not independently associated with lower mortality risk, with HR (95% CI) between extreme tertiles as follows: 0.77 (0.52-1.14; P_trend = 0.192) for high fiber intake; 0.81 (0.59-1.12; P_trend = 0.211) for low glycemic index; 0.87 (0.69-1.11; P_trend = 0.272) for high whole-grain carbohydrate: total-grain carbohydrate ratio; and 0.81 (0.61-1.07; P_trend = 0.139) for high solid carbohydrate: total carbohydrate ratio. Our analyses remained similar after using repeated measurements of diet with updated nutritional exposures after a ten-year follow-up.

CONCLUSIONS

The CQI as a whole, but none of its individual dimensions, was associated with lower mortality. The CQI seems to comprehensively capture the combined effects of quality domains.

Association between a dietary carbohydrate index and cardiovascular disease in the SUN (Seguimiento Universidad de Navarra) Project

BACKGROUND AND AIMS

Beyond the quantity of carbohydrate intake, further research is needed to know the relevance of carbohydrate quality following operational indices. No previous longitudinal study has assessed the association between an index for quality of dietary carbohydrate intake and the risk of cardiovascular disease (CVD). Here, we examined the association between a carbohydrate quality index (CQI) and the risk of CVD.

METHODS AND RESULTS

We used a validated semi-quantitative 136-item food-frequency questionnaire (FFQ) in a prospective follow-up study of 17,424 middle-aged adults from Spain. The CQI was defined by four criteria: dietary fiber intake, glycemic index, whole-grain/total-grain carbohydrate ratio, and solid/total carbohydrate ratio. We observed 129 incident cases of CVD during 10.1 y of median follow-up. An inverse association for CQI was found (hazard ratio = 0.44, 95% confidence interval (CI): 0.25-0.78 for the highest versus the lowest tertile, p for trend = 0.008). Participants in the highest tertile of the whole-grain/total-grain carbohydrate ratio had 47% lower risk of CVD (95% CI: 0.33-0.85, p for trend = 0.008). Participants with higher baseline CQI and higher baseline energy from carbohydrates had the lowest risk of CVD.

CONCLUSION

In this Mediterranean cohort, a better quality of dietary carbohydrates measured by the CQI, showed a significant inverse association with the incidence of CVD. Specially, a higher proportion of carbohydrates from whole grains was strongly inversely associated with CVD. "Heart-healthy" diets should be focused not only on carbohydrate quantity but also on a multidimensional assessment of the type and quality of carbohydrates.