Nutrition Journal - Latest Articles

Low glycaemic index diets improve glucose tolerance and body weight in women with previous history of gestational diabetes: a six months randomized trial

Sangeetha Shyam — 2013-05-24T00:00:00Z

Background: Gestational Diabetes Mellitus (GDM) increases risks for type 2 diabetes and weight management is recommended to reduce the risk. Conventional dietary recommendations (energy-restricted, low fat) have limited success in women with previous GDM. The effect of lowering Glycaemic Index (GI) in managing glycaemic variables and body weight in women post-GDM is unknown.ObjectiveTo evaluate the effects of conventional dietary recommendations administered with and without additional low-GI education, in the management of glucose tolerance and body weight in Asian women with previous GDM.MethodSeventy seven Asian, non-diabetic women with previous GDM, between 20- 40y were randomised into Conventional healthy dietary recommendation (CHDR) and low GI (LGI) groups. CHDR received conventional dietary recommendations only (energy restricted, low in fat and refined sugars, high-fibre). LGI group received advice on lowering GI in addition. Fasting and 2-h post-load blood glucose after 75g oral glucose tolerance test (2HPP) were measured at baseline and 6 months after intervention. Anthropometry and dietary intake were assessed at baseline, three and six months after intervention. The study is registered at the Malaysian National Medical Research Register (NMRR) with Research ID: 5183 Results: After 6 months, significant reductions in body weight, BMI and waist-to-hip ratio were observed only in LGI group (P<0.05). Mean BMI changes were significantly different between groups (LGI vs. CHDR: -0.6 vs. 0kg/m2, P= 0.03). More subjects achieved weight loss >=5% in LGI compared to CHDR group (33% vs. 8%, P=0.01). Changes in 2HPP were significantly different between groups (LGI vs. CHDR: median (IQR): -0.2(2.8) vs. +0.8 (2.0) mmol/L, P=0.025). Subjects with baseline fasting insulin>=2muIU/ml had greater 2HPP reductions in LGI group compared to those in the CHDR group (-1.9+/-0.42 vs. +1.31+/-1.4 mmol/L, P<0.001). After 6 months, LGI group diets showed significantly lower GI (57+/-5 vs. 64+/-6, P<0.001), GL (122+/-33 vs. 142+/-35, P=0.04) and higher fibre content (17+/-4 vs.13+/-4g, P<0.001). Caloric intakes were comparable between groups. Conclusion: In women post-GDM, lowering GI of healthy diets resulted in significant improvements in glucose tolerance and body weight reduction as compared to conventional low-fat diets with similar energy prescription.

Areca nut chewing and metabolic syndrome: evidence of a harmful relationship

Kashif Shafique — 2013-05-20T00:00:00Z

Background: There is some evidence which suggests that areca nut chewing has a relationship with metabolic syndrome. Areca nut chewing is continue to increase and so is the metabolic syndrome which is a major cause of cardiovascular mortality in developing countries. The aim of this study was to determine the relationship of raw areca nut and areca nut chewing with tobacco additives and metabolic syndrome. Methods: This cross sectional study was conducted on population of Karachi, Pakistan. Simple random sampling was implied using the voter list as a sampling frame. A detailed questionnaire about the demographic details of all subjects was filled and an informed consent obtained for blood sampling. Logistic regression analyses were carried out to investigate the relationship between areca nut chewing and metabolic syndrome. Results: Of the 1070 individuals, 192(17.9%) had metabolic syndrome with significantly higher (p-value <0.001) prevalence among females (26.3%) compared with males (11.4%). Eight individuals (11.1%) among non users had metabolic syndrome while significantly higher (p-value <0.001) proportion of both, raw areca nut users (n = 67, 29%) and areca users with tobacco additives (n = 45, 38.5%) had metabolic syndrome.The crude odds ratio for central obesity among raw areca nut users was 1.46 (95% CI 1.07-1.98) and among areca nut users with tobacco additives was 2.02 (95% CI 1.36-3.00), hypertension among raw areca nut users group was 1.31(0.96-1.78) and among areca nut users with tobacco additives group was 2.05 (95% CI 1.38-3.04). A significant positive association of raw areca nut chewing and metabolic syndrome was found among males (crude OR 2.74, 95% CI 1.52-4.95) and females (crude OR 3.80, 95% CI 2.32-6.20). Similarly, a significant positive association was found with regard to raw areca nut with tobacco additives chewing among males (crude OR 5.46, 95% CI 2.73-10.91) and females (crude OR 4.32, 95% CI 2.41-7.72). These associations remained significant adjustment for age, social class. Conclusions: This study suggests a harmful relationship between areca nut chewing and metabolic syndrome. The deleterious effects were even stronger among areca nut chewer with tobacco additives. Further research with longitudinal data might help to understand the temporal relationship between areca nut chewing and metabolic syndrome.

Effectiveness of nutrition training of health workers toward improving caregivers' feeding practices for children aged six months to two years: a systematic review

Bruno Sunguya — 2013-05-20T00:00:00Z

Background: Nutrition training of health workers can help to reduce child undernutrition. Specifically, trained health workers might contribute to this end through frequent nutrition counseling of caregivers. This may improve child-feeding practices and thus reduce the risk of undernutrition among children of counseled caregivers. Although studies have shown varied impacts of health workers' nutrition training on child feeding practices, no systematic review of the effectiveness of such intervention has yet been reported. Therefore, we conducted this study to examine the effectiveness of nutrition training for health workers on child feeding practices including feeding frequency, energy intake, and dietary diversity among children aged six months to two years. Methods: We searched the literature for published randomized controlled trials (RCTs) and cluster RCTs using medical databases including PubMed/MEDLINE, CINAHL, EMBASE, and ISI Web of Knowledge, and through WHO regional databases. Our intervention of interest was nutrition training of health workers. We pooled the results of the selected trials, evaluated them using the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) criteria, and calculated the overall effect size of the intervention in meta-analyses. Results: Ten RCTs and cluster RCTs out of 4757 retrieved articles were eligible for final analyses. Overall, health workers' nutrition training improved daily energy intake of children between six months and two years of age. The pooled evidence from the three studies reporting mean energy intake per day revealed a standardized mean difference (SMD) of 0.76, 95% CI (0.63-0.88). For the two studies with median energy intake SMD was 1.06 (95% CI 0.87-1.24). Health workers' nutrition training also improved feeding frequency among children aged six months to two years. The pooled evidence from the three studies reporting mean feeding frequency showed an SMD of 0.48 (95% CI 0.38-0.58). Regarding dietary diversity, children in intervention groups were more likely to consume more diverse diets compared to their counterparts.Conclusion and recommendations: Nutrition training for health workers can improve feeding frequency, energy intake, and dietary diversity of children aged six months to two years. Scaling up of nutrition training for health workers presents a potential entry point to improve nutrition status among children.

Ethnic differences in grains consumption and their contribution to intake of B-vitamins: Results of the Multiethnic Cohort Study

Sangita Sharma — 2013-05-20T00:00:00Z

Background: Research indicates that a diet rich in whole grains may reduce the risk of prevalent chronic diseases, including cardiovascular disease, diabetes, and some cancers, and that risk for these diseases varies by ethnicity. The objective of the current study was to identify major dietary sources of grains and describe their contribution to B vitamins in five ethnic groups. Methods: A cross-sectional mail survey was used to collect data from participants in the Multiethnic Cohort Study in Hawaii and Los Angeles County, United States, from 1993 to 1996. Dietary intake data collected using a quantitative food frequency questionnaire was available for 186,916 participants representing five ethnic groups (African American, Latino, Japanese American, Native Hawaiian and Caucasian) aged 45--75 years. The top sources of grain foods were determined, and their contribution to thiamin, riboflavin, niacin, vitamin B6, and folic acid intakes were analyzed. Results: The top source of whole grains was whole wheat/rye bread for all ethnic-sex groups, followed by popcorn and cooked cereals, except for Native Hawaiian men and Japanese Americans, for whom brown/wild rice was the second top source; major contributors of refined grains were white rice and white bread, except for Latinos. Refined grain foods contributed more to grain consumption (27.1-55.6%) than whole grain foods (7.4-30.8%) among all ethnic-sex groups, except African American women. Grain foods made an important contribution to the intakes of thiamin (30.2-45.9%), riboflavin (23.1-29.2%), niacin (27.1-35.8%), vitamin B6 (22.9-27.5%), and folic acid (23.3-27.7%). Conclusions: This is the first study to document consumption of different grain sources and their contribution to B vitamins in five ethnic groups in the U.S. Findings can be used to assess unhealthful food choices, to guide dietary recommendations, and to help reduce risk of chronic diseases in these populations.

Effect of consumption of micronutrient enriched wheat steamed bread on postprandial plasma glucose in healthy and type 2 diabetic subjects

Su-Que Lan — 2013-05-17T00:00:00Z

Background: Steamed wheat bread have previously been shown to induce comparatively high postprandial plasma glucose responses, on the contrary, buckwheat products induced lower postprandial plasma glucose. The present study was to assess the effects of micronutrient enriched bread wheat variety Jizi439 and buckwheat on postprandial plasma glucose in healthy and diabetic subjects comparing with buckwheat and other bread wheat varieties. Methods: Two experiments were conducted to study the effects of bread wheat variety Jizi439 on the postprandial plasma glucose levels of the randomly selected subjects. The first experiment involved three types of steamed bread with equivalent of 50g available carbohydrate fed to 10 normal weight young healthy subjects. Two types of steamed bread were made from two purple-grain bread wheat varieties, Jizi439 and Chu20, respectively, and the third type was made from the mixture of different white grain wheat varieties. Plasma glucose levels of each subject were measured at 15, 30, 45, 60, 120 min after eating. Glucose was used as a reference, the total area under curve (AUC) and glycemic index (GI) was calculated for test meal. The second experiment was performed among ten type 2 diabetics who were served equivalent of 50g available carbohydrate of steamed bread made from Jizi 439, the mixture of white grain bread wheat and buckwheat, respectively. The plasma glucose increment was determined two hours thereafter. Results: In the first experiment, consumption of the steamed bread made from Jizi439 resulted in the least increase in plasma glucose and the GI was significantly lower than that of Chu20 and the mixture. In the second experiment, the average of postprandial 2h plasma glucose increment of Jizi439 was 2.46mmol/L which was significantly lower than that of the mixture of white wheat but was not significantly different from buckwheat. Conclusions: The results indicated that consumption of Jizi439 steamed bread resulted in significantly lower plasma glucose in both healthy and diabetic subjects, compared with other types of test foods, except buckwheat bread. The steam bread made from Jizi439 would be an ideal food for preventing and treatment of diabetes.

Factors relating to eating style, social desirability, body image and eating meals at home increase the precision of calibration equations correcting self-report measures of diet using recovery biomarkers: findings from the Women¿s Health Initiative

Yasmin Mossavar-Rahmani — 2013-05-16T00:00:00Z

Background: The extent to which psychosocial and diet behavior factors affect dietary self-report remains unclear. We examine the contribution of these factors to measurement error of self-report. Methods: In 450 postmenopausal women in the Women’s Health Initiative Observational Study doubly labeled water and urinary nitrogen were used as biomarkers of objective measures of total energy expenditure and protein. Self-report was captured from food frequency questionnaire (FFQ), four day food record (4DFR) and 24 hr. dietary recall (24HR). Using regression calibration we estimated bias of self-reported dietary instruments including psychosocial factors from the Stunkard-Sorenson Body Silhouettes for body image perception, the Crowne-Marlowe Social Desirability Scale, and the Three Factor Eating Questionnaire (R-18) for cognitive restraint for eating, uncontrolled eating, and emotional eating. We included a diet behavior factor on number of meals eaten at home using the 4DFR. Results: Three categories were defined for each of the six psychosocial and diet behavior variables (low, medium, high). Participants with high social desirability scores were more likely to under-report on the FFQ for energy (β = -0.174, SE = 0.054, p < 0.05) and protein intake (β = -0.142, SE = 0.062, p < 0.05) compared to participants with low social desirability scores. Participants consuming a high percentage of meals at home were less likely to under-report on the FFQ for energy (β = 0.181, SE = 0.053, p < 0.05) and protein (β = 0.127, SE = 0.06, p < 0.05) compared to participants consuming a low percentage of meals at home. In the calibration equations combining FFQ, 4DFR, 24HR with age, body mass index, race, and the psychosocial and diet behavior variables, the six psychosocial and diet variables explained 1.98%, 2.24%, and 2.15% of biomarker variation for energy, protein, and protein density respectively. The variations explained are significantly different between the calibration equations with or without the six psychosocial and diet variables for protein density (p = 0.02), but not for energy (p = 0.119) or protein intake (p = 0.077). Conclusions: The addition of psychosocial and diet behavior factors to calibration equations significantly increases the amount of total variance explained for protein density and their inclusion would be expected to strengthen the precision of calibration equations correcting self-report for measurement error.Trial registrationClinicalTrials.gov identifier: NCT00000611

The potential role of phytochemicals in wholegrain cereals for the prevention of type-2 diabetes

Damien Belobrajdic — 2013-05-16T00:00:00Z

Diets high in wholegrains are associated with a 20-30% reduction in risk of developing type-2 diabetes (T2D), which is attributed to a variety of wholegrain components, notably dietary fibre, vitamins, minerals and phytochemicals. Most phytochemicals function as antioxidants in vitro and have the potential to mitigate oxidative stress and inflammation which are implicated in the pathogenesis of T2D. In this review we compare the content and bioavailability of phytochemicals in wheat, barley, rice, rye and oat varieties and critically evaluate the evidence for wholegrain cereals and cereal fractions increasing plasma phytochemical concentrations and reducing oxidative stress and inflammation in humans. Phytochemical content varies considerably within and among the major cereal varieties. Differences in genetics and agro-climatic conditions explain much of the variation. For a number of the major phytochemicals, such as phenolics and flavanoids, their content in grains may be high but because these compounds are tightly bound to the cell wall matrix, their bioavailability is often limited. Clinical trials show that postprandial plasma phenolic concentrations are increased after consumption of wholegrain wheat or wheat bran however the magnitude of the response is usually modest and transient. Whether this is sufficient to bolster antioxidant defences and translates into improved health outcomes is still uncertain. Increased phytochemical bioavailability may be achieved through bio-processing of grains but the improvements so far are small and have not yet led to changes in clinical or physiological markers associated with reduced risk of T2D. Furthermore, the effect of wholegrain cereals and cereal fractions on biomarkers of oxidative stress or strengthening antioxidant defence in healthy individuals is generally small or nonexistent, whereas biomarkers of systemic inflammation tend to be reduced in people consuming high intakes of wholegrains. Future dietary intervention studies seeking to establish a direct role of phytochemicals in mediating the metabolic health benefits of wholegrains, and their potential for mitigating disease progression, should consider using varieties that deliver the highest possible levels of bioavailable phytochemicals in the context of whole foods and diets. Both postprandial and prolonged responses in systemic phytochemical concentrations and markers of inflammation and oxidative stress should be assessed along with changes related to health outcomes in healthy individuals as well as those with metabolic disease.

Intakes of calcium, vitamin D, and dairy servings and dental plaque in older Danish adults

Amanda Adegboye — 2013-05-16T00:00:00Z

Background: To investigate whether intakes of calcium and dairy-servings within-recommendations were associated with plaque score when allowing for vitamin D intakes. Methods: In this cross-sectional study, including 606 older Danish adults, total dietary calcium intake (mg/day) was classified as below vs. within-recommendations and dairy intake as <3 vs. >=3 servings/ d. Dental plaque, defined as the percentage of tooth surfaces exhibiting plaque, was classified as < median vs. >=median value (9.5%). Analyses were stratified by lower and higher (>=6.8 mug/d) vitamin D intake.FindingsIntakes of calcium (OR = 0.53; 95%CI = 0.31--0.92) and dairy servings (OR = 0.54; 95%CI = 0.33--0.89) within-recommendations were significantly associated with lower plaque score after adjustments for age, gender, education, intakes of alcohol, sucrose and mineral supplements, smoking, diseases, number of teeth, visits to the dentist, use of dental floss/tooth pick and salivary flow, among those with higher, but not lower, vitamin D intake. Conclusion: Intakes of calcium dairy-servings within-recommendations were inversely associated with plaque, among those with higher, but not lower, vitamin D intakes. Due to the cross-sectional nature of the study, it is not possible to infer that this association is causal.

Diurnal variation of phenylalanine and tyrosine concentrations in adult patients with phenylketonuria: subcutaneous microdialysis is no adequate tool for the determination of amino acid concentrations

Sarah Grünert — 2013-05-14T00:00:00Z

Background: Metabolic control and dietary management of patients with phenylketonuria (PKU) are based on single blood samples obtained at variable intervals. Sampling conditions are often not well-specified and intermittent variation of phenylalanine concentrations between two measurements remains unknown. We determined phenylalanine and tyrosine concentrations in blood over 24 hours. Additionally, the impact of food intake and physical exercise on phenylalanine and tyrosine concentrations was examined. Subcutaneous microdialysis was evaluated as a tool for monitoring phenylalanine and tyrosine concentrations in PKU patients. Methods: Phenylalanine and tyrosine concentrations of eight adult patients with PKU were determined at 60 minute intervals in serum, dried blood and subcutaneous microdialysate and additionally every 30 minutes postprandially in subcutaneous microdialysate. During the study period of 24 hours individually tailored meals with defined phenylalanine and tyrosine contents were served at fixed times and 20 min bicycle-ergometry was performed. Results: Serum phenylalanine concentrations showed only minor variations while tyrosine concentrations varied significantly more over the 24-hour period. Food intake within the patients’ individual diet had no consistent effect on the mean phenylalanine concentration but the tyrosine concentration increased up to 300% individually. Mean phenylalanine concentration remained stable after short-term bicycle-exercise whereas mean tyrosine concentration declined significantly. Phenylalanine and tyrosine concentrations in dried blood were significantly lower than serum concentrations. No close correlation has been found between serum and microdialysis fluid for phenylalanine and tyrosine concentrations. Conclusions: Slight diurnal variation of phenylalanine concentrations in serum implicates that a single blood sample does reliably reflect the metabolic control in this group of adult patients. Phenylalanine concentrations determined by subcutaneous microdialysis do not correlate with the patients’ phenylalanine concentrations in serum/blood.

Energy intakes of US children and adults by food purchase location and by specific food source

Adam Drewnowski — 2013-05-08T00:00:00Z

Background: To our knowledge, no studies have examined energy intakes by food purchase location and food source using a representative sample of US children, adolescents and adults. Evaluations of purchase location and food sources of energy may inform public health policy. Methods: Analyses were based on the first day of 24-hour recall for 22,852 persons in the 2003-4, 2005-6, and 2007-8 National Health and Nutrition Examination Surveys (NHANES). The most common food purchase locations were stores (grocery store, supermarket, convenience store, or specialty store), quick-service restaurants/pizza (QSR), full-service restaurants (FSR), school cafeterias, or food from someone else/gifts. Specific food sources of energy were identified using the National Cancer Institute aggregation scheme. Separate analyses were conducted for children ages 6-11y, adolescents ages 12-19y, and adults aged 20-50y and ≥51y. Results: Stores (grocery, convenience, and specialty) were the food purchase locations for between 63.3% and 70.3% of dietary energy in the US diet. Restaurants provided between 16.9% and 26.3% of total energy. Depending on the respondents’ age, QSR provided between 12.5% and 17.5% of energy, whereas FSR provided between 4.7% and 10.4% of energy. School meals provided 9.8% of energy for children and 5.5% for adolescents. Vending machines provided <1% of energy. Pizza from QSR, the top food away from home (FAFH) item, provided 2.2% of energy in the diets of children and 3.4% in the diets of adolescents. Soda, energy, and sports drinks from QSR provided approximately 1.2% of dietary energy. Conclusions: Refining dietary surveillance approaches by incorporating food purchase location may help inform public health policy. Characterizing the important sources of energy, in terms of both purchase location and source may be useful in anticipating the population-level impacts of proposed policy or educational interventions. These data show that stores provide a majority of energy for the population, followed by quick-service and full-service restaurants. All food purchase locations, including stores, restaurants and schools play an important role in stemming the obesity epidemic.