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App-technology to improve lifestyle behaviors among working adults - the Health Integrator study, a randomized controlled trial.
Bonn, SE, Löf, M, Östenson, CG, Trolle Lagerros, Y
BMC public health. 2019;19(1):273
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Lifestyle is the single most important factor to improve health and decrease premature death. Digital solutions for implementing lifestyle change and tracking different types of health data are becoming popular preventative initiatives. The main aim of this study was to evaluate whether a digital platform (The Health Integrator) accessible via a smartphone-app offering lifestyle intervention, with and without additional health coach guidance, can be used to make lifestyle changes and improve health related quality of life in gainfully employed persons. The Health Integrator intervention study is a three-arm parallel randomized controlled trial. Participants were randomized to 1 of 3 groups: 1) intervention using Health Integrator and a monthly telephone session with the health coach during the 3 months of follow-up or 2) intervention using Health Integrator without extra health coach sessions or 3) control group which is not given any lifestyle advise during the intervention period. The study is still ongoing. However, mobile Health has been suggested as one way to take global action as it has the potential to make treatment and prevention widely accessible at a fraction of the current cost. In fact, Health Integrator was developed on the basis of previous research. Current literature shows that multi-component interventions including for example face-to-face counselling or provision of physical activity equipment in addition to an app, were more successful than a stand-alone app intervention.
Abstract
BACKGROUND Mobile health, mHealth is recognized as a strategy to improve lifestyle behaviors. Research targeting specific lifestyle behaviors has shown that interventions using smartphones can be effective. However, few studies have evaluated solutions with multicomponent interventions, tailoring the intervention to the specific needs of the participant using a combination of mHealth and conventional treatment. To accomplish this, we developed Health Integrator, an mHealth platform with services and offers in the areas of diet, physical activity, sleeping habits, stress, alcohol and tobacco use. In the system, the user selects an area of intervention together with a health coach and set weekly goals. This study protocol presents the design and methodology of the Health Integrator Study, a randomized controlled trial to promote improved lifestyle behaviors. METHODS A three-arm parallel randomized controlled trial (1:1:1) is conducted in the Stockholm County, Sweden. In total, 209 employees at a four different companies representing both white and blue collar workers, have been recruited. Participants are randomized to either a control group or to one of two intervention groups receiving a 3-month lifestyle behavior change program including either 1) use of Health Integrator and monthly health coaching sessions or 2) only Health Integrator. At baseline and follow-up after 3- and 6-months, all participants answer questionnaires assessing lifestyle behaviors and quality of life. At baseline and the 3-month follow-up (end of intervention period), weight, height, waist circumference and blood pressure are measured, and all participants wear an Actigraph accelerometer for 7 days to assess physical activity. Blood lipid profile and HbA1c are measured among all participants at baseline. If baseline measures fall outside the normal range, a second measurement is done after 3 months. DISCUSSION The Health Integrator Intervention Study will evaluate if a personalized intervention combining mHealth and conventional programs for lifestyle change, with or without additional health coach sessions, can improve lifestyle behaviors and quality of life. Based on the results from this trial, Health Integrator can easily be implemented within a broad public. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT03579342 . Retrospectively registered, first submitted May 8, 2018.
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Cashew apple juice supplementation enhances leukocyte count by reducing oxidative stress after high-intensity exercise in trained and untrained men.
Prasertsri, P, Roengrit, T, Kanpetta, Y, Tong-Un, T, Muchimapura, S, Wattanathorn, J, Leelayuwat, N
Journal of the International Society of Sports Nutrition. 2019;16(1):31
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High-intensity aerobic training has been shown to suppress leukocyte counts in moderately fit athletes. The aim of this study to explore possible advantageous effects of cashew apple juice (CAJ) supplementation, and, if present, to identify the possible mechanisms underlying those effects. The study is a double-blind randomised cross-over design with two treatment arms: CAJ supplementation and placebo. Ten moderately (endurance) trained and untrained men were randomized to one of the two groups for four weeks, with a four-week wash out period. Results showed that CAJ supplementation for four weeks increased leukocyte (a type of blood cell) counts, while simultaneously decreasing oxidative stress, following an acute bout of high-intensity exercise in trained men. Furthermore, the CAJ supplementation increased neutrophil (a type of white blood cell) counts while simultaneously reducing oxidative stress and stress hormone concentrations in untrained men. The antioxidant effects following exercise were observed in both endurance-trained and untrained men. Authors conclude that CAJ supplementation is beneficial to men, both in resting states and in response to an acute bout of high-intensity aerobic exercise.
Abstract
BACKGROUND Cashew apple juice (CAJ) was shown to improve immunological mechanisms by regulating a balance between reactive oxygen species and antioxidant concentrations. However, no study exploring the effects of the CAJ and training status on the immune system and oxidative stress induced by exercise. Therefore, we investigated the effects of CAJ supplementation primarily on leukocyte counts and secondary on oxidative stress and cortisol changes after high-intensity exercise in trained and untrained men. METHODS Ten moderately (endurance) trained (Age = 21.5 ± 0.97 yr., VO2max = 45.6 ± 4.12 mL/kgBM/min) and ten sedentary men (Age = 20.4 ± 2.72 yr., VO2peak = 32.2 ± 7.26 mL/kgBM/min) were randomized to ingest either daily CAJ or a placebo at 3.5 mL/kgBM/day for 4 weeks, with a four-week washout period. Before and after each period, they performed 20-min, high-intensity cycling (85% VO2max), with blood samples collected immediately preceding and the following exercise. Samples were analyzed to determine leukocyte counts, malondialdehyde, 8-isoprostane, and cortisol concentrations. A repeated measures analysis of variance was used to examine the effects of supplement and training status over time with an alpha level of 0.05. RESULTS There was no interaction between supplement and training status on those variables before and after exercise. However, CAJ raised resting neutrophil counts and exercise-induced leukocyte counts in the trained group (all p < 0.05). Besides, CAJ significantly reduced plasma malondialdehyde concentrations at rest and after exercise and reduced the post-exercise plasma 8-isoprostane concentration in both groups of subjects (p < 0.05). Moreover, CAJ reduced plasma cortisol after exercise in the untrained subjects. CONCLUSIONS We suggest that 4-week CAJ supplementation can enhance exercise-induced leukocyte and resting neutrophil counts in trained men. The possible mechanism is a reduction in oxidative stress. However, the supplementation did not change the immune responses of untrained men, but it did reduce stress hormone concentrations. TRIAL REGISTRATION NUMBER TCTR20181127002 Registered 26 November 2018 "retrospectively registered".
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The Obemat2.0 Study: A Clinical Trial of a Motivational Intervention for Childhood Obesity Treatment.
Luque, V, Feliu, A, Escribano, J, Ferré, N, Flores, G, Monné, R, Gutiérrez-Marín, D, Guillen, N, Muñoz-Hernando, J, Zaragoza-Jordana, M, et al
Nutrients. 2019;11(2)
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Multicomponent interventions consisting of dietary modification, physical activity, behavioural therapy, and education have shown to improve body mass index, blood pressure, and lipids profile. The Obemat2.0 trail was designed and conducted to implement and to test the efficacy of a structured multicomponent motivational therapy to treat childhood obesity. The study is a randomised clustered clinical trial with a treatment on children with obesity lasting 12 months. The study had two arms: a control group and an intervention group. The recruitment started in June 2016 and the fieldwork is expected to end in June 2019. The study results will show whether a multicomponent program, including a bundle of motivational strategies conducted in primary centres by therapists with 12h of specific training could be more effective than usual care. Authors expect this clinical trial to open a window of opportunity to support professionals at the primary care level to treat childhood obesity.
Abstract
The primary aim of the Obemat2.0 trial was to evaluate the efficacy of a multicomponent motivational program for the treatment of childhood obesity, coordinated between primary care and hospital specialized services, compared to the usual intervention performed in primary care. This was a cluster randomized clinical trial conducted in Spain, with two intervention arms: motivational intervention group vs. usual care group (as control), including 167 participants in each. The motivational intervention consisted of motivational interviewing, educational materials, use of an eHealth physical activity monitor and three group-based sessions. The primary outcome was body mass index (BMI) z score increments before and after the 12 (+3) months of intervention. Secondary outcomes (pre-post intervention) were: adherence to treatment, waist circumference (cm), fat mass index (z score), fat free mass index (z score), total body water (kg), bone mineral density (z score), blood lipids profile, glucose metabolism, and psychosocial problems. Other assessments (pre and post-intervention) were: sociodemographic information, physical activity, sedentary activity, neuropsychological testing, perception of body image, quality of the diet, food frequency consumption and foods available at home. The results of this clinical trial could open a window of opportunity to support professionals at the primary care to treat childhood obesity. The clinicaltrials.gov identifier was NCT02889406.
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Lifestyle and vascular risk effects on MRI-based biomarkers of Alzheimer's disease: a cross-sectional study of middle-aged adults from the broader New York City area.
Mosconi, L, Walters, M, Sterling, J, Quinn, C, McHugh, P, Andrews, RE, Matthews, DC, Ganzer, C, Osorio, RS, Isaacson, RS, et al
BMJ open. 2018;8(3):e019362
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Alzheimer’s disease (AD) is the most common form of dementia, affecting nearly 34 million people worldwide. It has been estimated that one in every three cases of AD may be attributable to diet and lifestyle factors. The aim of this study was to investigate the effects of lifestyle and vascular-related risk factors for AD. Researchers studied the brain scans of 116 healthy adults aged 30-60 years. They collected information on factors related to lifestyle, such as diet, physical activity and intellectual enrichment. They also looked at markers for vascular risk such as body mass index (BMI), cholesterol and homocysteine, as well as cognitive function. The researchers found that a Mediterranean-style diet and good insulin sensitivity were both associated with a healthier brain structure. A better score for intellectual enrichment and lower BMI were both associated with better cognition. They concluded that adopting a Mediterranean-style diet and maintaining a healthy weight might reduce the risk of developing AD.
Abstract
OBJECTIVE To investigate the effects of lifestyle and vascular-related risk factors for Alzheimer's disease (AD) on in vivo MRI-based brain atrophy in asymptomatic young to middle-aged adults. DESIGN Cross-sectional, observational. SETTING Broader New York City area. Two research centres affiliated with the Alzheimer's disease Core Center at New York University School of Medicine. PARTICIPANTS We studied 116 cognitively normal healthy research participants aged 30-60 years, who completed a three-dimensional T1-weighted volumetric MRI and had lifestyle (diet, physical activity and intellectual enrichment), vascular risk (overweight, hypertension, insulin resistance, elevated cholesterol and homocysteine) and cognition (memory, executive function, language) data. Estimates of cortical thickness for entorhinal (EC), posterior cingulate, orbitofrontal, inferior and middle temporal cortex were obtained by use of automated segmentation tools. We applied confirmatory factor analysis and structural equation modelling to evaluate the associations between lifestyle, vascular risk, brain and cognition. RESULTS Adherence to a Mediterranean-style diet (MeDi) and insulin sensitivity were both positively associated with MRI-based cortical thickness (diet: βs≥0.26, insulin sensitivity βs≥0.58, P≤0.008). After accounting for vascular risk, EC in turn explained variance in memory (P≤0.001). None of the other lifestyle and vascular risk variables were associated with brain thickness. In addition, the path associations between intellectual enrichment and better cognition were significant (βs≥0.25 P≤0.001), as were those between overweight and lower cognition (βs≥-0.22, P≤0.01). CONCLUSIONS In cognitively normal middle-aged adults, MeDi and insulin sensitivity explained cortical thickness in key brain regions for AD, and EC thickness predicted memory performance in turn. Intellectual activity and overweight were associated with cognitive performance through different pathways. Our findings support further investigation of lifestyle and vascular risk factor modification against brain ageing and AD. More studies with larger samples are needed to replicate these research findings in more diverse, community-based settings.
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Vitamin D nutritional status and its relationship with metabolic changes in adolescents and adults with severe obesity.
Teixeira, JS, Bull Ferreira Campos, A, Cordeiro, A, Pereira, SE, Saboya, CJ, Ramalho, A
Nutricion hospitalaria. 2018;35(4):847-853
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In adolescents, severe obesity may lead to a high risk of premature mortality and morbidity in adult life. Increased vitamin D deficiency (VDD) occurs together with obesity. The main aim of this study was to assess the nutritional status of vitamin D and metabolic profile in adolescents and adults with obesity. The study is a comparative observational study which included 128 individuals. A total of 60 participants comprised the adolescent group (G1), (63.3% female) whereas 68 participants comprised the adult group (G2), (75% female). Results indicate: - a high prevalence of inadequacy of Vitamin D in both groups. - a trend of association of elevated blood glucose with the inadequacy of Vitamin D in the adolescent group. - a high prevalence of VDD and non-alcoholic fatty liver disease in both groups. - no relationship between Vitamin D and high blood pressure or metabolic syndrome in any of the groups evaluated. Authors conclude that strategies for the prevention and control of obesity and for the fight against the inadequacy of the nutritional status of vitamin D should be developed.
Abstract
INTRODUCTION increased vitamin D deficiency occurs together with obesity and the association between these conditions has been observed. OBJECTIVE to assess the nutritional status of vitamin D and metabolic profile in adolescents and adults with obesity, and the relationship between complications arising from severe class of obesity with vitamin D nutritional status, and to compare the differences between these groups. METHODS observational comparative study. Population comprises adolescents and adults with severe obesity. Waist circumference (WC) and body mass index (BMI) were measured. Analysis of vitamin D (25(OH)D), lipid profile, C-reactive protein (CRP), blood glucose, fasting insulinemia, insulin sensitivity, blood pressure and diagnoses of nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome (MS) were performed. RESULTS a total of 60 adolescents (G1) and 68 adults (G2) were evaluated. The percentage of vitamin D inadequacy was observed in 90% in G1 and 79.4% in G2. There was a negative and significant correlation of BMI with the values of 25(OH)D in the group of adults (r = -0.244; p = 0.045). Individuals with inadequacy of vitamin D showed higher values of CRP in both groups (p = 0.000). HOMA-IR showed a negative correlation with 25(OH)D in G1 (r = -0.832; p = 0.000) and G2 (r = -0.589; p = 0.000). The inadequacy of this vitamin showed association with high total cholesterol in G1 (p = 0.029) and higher values of LDL-c in G2 (p = 0.003). CONCLUSION high prevalence of deficiency and insufficiency of vitamin D were observed, associated with metabolic changes both in obese adults and adolescents. It is necessary to develop strategies for the prevention and control of obesity and vitamin D deficiency.
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Acute Endothelial Benefits of Fat Restriction over Carbohydrate Restriction in Type 2 Diabetes Mellitus: Beyond Carbs and Fats.
Barbosa-Yañez, RL, Dambeck, U, Li, L, Machann, J, Kabisch, S, Pfeiffer, AFH
Nutrients. 2018;10(12)
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The control of type 2 diabetes mellitus has become a global challenge. Cardiovascular disease is a major cause of mortality in type 2 diabetes. The aim of the study is to examine and compare the effect of a hypocaloric very low carbohydrate diet versus hypocaloric low-fat diet on vascular function and visceral adipose tissue in type 2 diabetic patients. The study is a randomised parallel group intervention study with adult type 2 diabetes patients with an age range between 42 and 76 years. Results show that both dietary strategies effectively reduced body weight, total adipose tissue, visceral adipose tissue and lipid accumulation in the liver. However, participants following the low-fat diet experienced greater vascular function enhancements. Authors conclude that low-fat diet elicited advantageous effects on vascular function in patients with type 2 diabetes.
Abstract
BACKGROUND Cardiovascular diseases (CVD) are the major cause of mortality in type 2 diabetes patients (T2DM). The causes are embedded in a complex interplay between excess body fat, insulin resistance and serum lipid anomalies. Endothelial homeostasis is strongly affected by this pathogenic network. Even though metabolic changes and weight loss improve vascular endothelial function, the effect of different dietary approaches is still uncertain for type 2 diabetes patients. OBJECTIVE We aimed to compare the acute effects of a hypocaloric very low carbohydrate (VLC) diet versus a hypocaloric low fat (LF) diet on flow mediated dilation (FMD), intrahepatic lipid (IHL) accumulation and visceral adipose tissue as independent risk factors of CVD in T2DM patients. DESIGN 36 T2DM patients (age 63 ± 8 years, 60% females) were randomly assigned to the VLC diet (4⁻10% of total energy intake (E)) or to the LF diet (<30% E) for 3 weeks. Endothelial function was assessed by the flow mediated dilation (FMD) method. Adipose tissue depots and IHL were determined by magnetic resonance. RESULTS Both dietary strategies reduced body weight, body fat content and IHL. Unexpectedly, the LF group experienced significantly greater enhancement of FMD, compared to the VLC group. The FMD showed a positive correlation with protein intake and fat intake in the LF group, while it revealed a negative correlation with protein intake in the VLC diet group. CONCLUSIONS Reduction of total and hepatic adiposity was shown to be successful using either the VLC or LF hypocaloric diets, however, improvements in FMD may be related to the interplay of fat and protein intake.
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A whole-grain diet reduces peripheral insulin resistance and improves glucose kinetics in obese adults: A randomized-controlled trial.
Malin, SK, Kullman, EL, Scelsi, AR, Haus, JM, Filion, J, Pagadala, MR, Godin, JP, Kochhar, S, Ross, AB, Kirwan, JP
Metabolism: clinical and experimental. 2018;82:111-117
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Literature shows that dietary whole-grain intake is associated with a lower incidence of type 2 diabetes. The aim of the study was to investigate the association between a whole-grain diet and insulin resistance and glucose use in individuals at risk for type 2 diabetes. The study was a randomized, double-blind, controlled crossover trial involving fourteen middle-aged, obese adults at risk for diabetes. Randomisation was carried out prior to metabolic testing. Results indicate that whole-grain intake as part of a mixed-meal diet significantly improved post-prandial (after a meal) glucose metabolism in middle-aged obese adults. Furthermore, both whole-grain and refined-grain interventions induced about 3–6% weight and fat loss. Authors conclude that whole-grain intake effectively promotes glycaemic control by improving insulin action.
Abstract
BACKGROUND Whole-grain intake is associated with lower risk of type 2 diabetes but the mechanisms are unclear. PURPOSE We tested the hypothesis that a WG diet reduces insulin resistance and improves glucose use in individuals at risk for type 2 diabetes compared with an isocaloric-matched refined-grain diet. METHODS A double-blind, randomized, controlled, crossover trial of 14 moderately obese adults (Age, 38 ± 2 y; BMI, 34.0 ± 1.1 kg/m2). Insulin resistance and glucose metabolism was assessed using an oral glucose tolerance test combined with isotopic tracers of [6,6-2H2]-glucose and [U-13C]-glucose, and indirect calorimetry. Peripheral and hepatic insulin resistance was assessed as 1/(rate of disposal/insulin), and endogenous glucose rates of appearance (Ra) iAUC60-240 × insulin iAUC60-240, respectively. Both diets met ADA nutritional guidelines and contained either whole-grain (50 g per 1000 kcal) or equivalent refined-grain. All food was provided for 8 wk. with an 8-10 wk. washout period between diets. RESULTS Post-prandial glucose tolerance, peripheral insulin sensitivity, and metabolic flexibility (insulin-stimulated - fasting carbohydrate oxidation) improvements were greater after whole-grain compared to the refined-grain diet (P < 0.05). Compared to baseline, body fat (~2 kg) and hepatic Ra insulin resistance was reduced by both diets, while fasting glucose and exogenous glucose-meal were unchanged after both interventions. Changes in peripheral insulin resistance and metabolic flexibility correlated with improved glucose tolerance (P < 0.05). CONCLUSION Whole-grains reduced diabetes risk and the mechanisms appear to work through reduced post-prandial blood glucose and peripheral insulin resistance that were statistically linked to enhanced metabolic flexibility.
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Sleep restriction increases the neuronal response to unhealthy food in normal-weight individuals.
St-Onge, MP, Wolfe, S, Sy, M, Shechter, A, Hirsch, J
International journal of obesity (2005). 2014;38(3):411-6
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Sleep patterns influence eating behaviour and the body’s response to food. Previous studies suggest that short sleep duration leads to increased caloric intake and a desire for high-fat foods, however the specific neural mechanisms explaining how sleep restriction modulates this response is unknown. The aim of this study was to determine whether a specific area of the brain is activated in response to unhealthy compared with healthy foods. 25 participants were included, all of which were normal weight and had normal sleeping patterns. Each participant was tested after five nights of either 4 or 9 hours in bed by functional magnetic resonance imaging (fMRI). The test was performed while the participant was shown healthy and unhealthy food photos in the fasted state. This study found that after a period of restricted sleep compared with habitual sleep, unhealthy foods led to greater activation in brain regions associated with reward compared with healthy foods. This finding provides a model of neuronal mechanisms relating short sleep duration to obesity and cardio-metabolic risk factors and warrants further investigation.
Abstract
CONTEXT Sleep restriction alters responses to food. However, the underlying neural mechanisms for this effect are not well understood. OBJECTIVE The purpose of this study was to determine whether there is a neural system that is preferentially activated in response to unhealthy compared with healthy foods. PARTICIPANTS Twenty-five normal-weight individuals, who normally slept 7-9 h per night, completed both phases of this randomized controlled study. INTERVENTION Each participant was tested after a period of five nights of either 4 or 9 h in bed. Functional magnetic resonance imaging (fMRI) was performed in the fasted state, presenting healthy and unhealthy food stimuli and objects in a block design. Neuronal responses to unhealthy, relative to healthy food stimuli after each sleep period were assessed and compared. RESULTS After a period of restricted sleep, viewing unhealthy foods led to greater activation in the superior and middle temporal gyri, middle and superior frontal gyri, left inferior parietal lobule, orbitofrontal cortex, and right insula compared with healthy foods. These same stimuli presented after a period of habitual sleep did not produce marked activity patterns specific to unhealthy foods. Further, food intake during restricted sleep increased in association with a relative decrease in brain oxygenation level-dependent (BOLD) activity observed in the right insula. CONCLUSION This inverse relationship between insula activity and food intake and enhanced activation in brain reward and food-sensitive centers in response to unhealthy foods provides a model of neuronal mechanisms relating short sleep duration to obesity.
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Glycemic load effect on fasting and post-prandial serum glucose, insulin, IGF-1 and IGFBP-3 in a randomized, controlled feeding study.
Runchey, SS, Pollak, MN, Valsta, LM, Coronado, GD, Schwarz, Y, Breymeyer, KL, Wang, C, Wang, CY, Lampe, JW, Neuhouser, ML
European journal of clinical nutrition. 2012;66(10):1146-52
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Dietary intervention studies have shown detrimental metabolic effects of high-glycaemic load diets. The glycaemic index (GI) is the numerical classification of a particular food’s blood glucose-raising effect. The aim of this study was to evaluate the effect of a high-glycaemic load diet on circulating levels of insulin-like growth factor-1 (IGF-1) [hormone] and insulin-like growth factor-binding protein 3 (IGFBP-3) [protein] compared to a low-glycaemic load diet. The study is a randomised controlled crossover study which enrolled 84 normal weight and overweight-obese healthy individuals. The study included two 28-day weight-maintaining high- and low-glycaemic load diets. Results indicate that consumption of a low-glycaemic load diet resulted in lower post-prandial [after a meal] insulin and glucose responses and modestly lower fasting IGF-1 and IGF-1/IGFBP-3 concentrations. However, there were no observable effects of glycaemic load on insulin resistance or glucose-adjusted post-prandial insulin responses in these healthy participants. Authors conclude that further intervention studies are required in order to weigh the impact of dietary glycaemic load on risk for chronic disease.
Abstract
BACKGROUND/OBJECTIVES The effect of a low glycemic load (GL) diet on insulin-like growth factor-1 (IGF-1) concentration is still unknown but may contribute to lower chronic disease risk. We aimed to assess the impact of GL on concentrations of IGF-1 and IGF-binding protein-3 (IGFBP-3). SUBJECTS/METHODS We conducted a randomized, controlled crossover feeding trial in 84 overweight obese and normal weight healthy individuals using two 28-day weight-maintaining high- and low-GL diets. Measures were fasting and post-prandial concentrations of insulin, glucose, IGF-1 and IGFBP-3. In all 80 participants completed the study and 20 participants completed post-prandial testing by consuming a test breakfast at the end of each feeding period. We used paired t-tests for diet component and linear mixed models for biomarker analyses. RESULTS The 28-day low-GL diet led to 4% lower fasting concentrations of IGF-1 (10.6 ng/ml, P=0.04) and a 4% lower ratio of IGF-1/IGFBP-3 (0.24, P=0.01) compared with the high-GL diet. The low-GL test breakfast led to 43% and 27% lower mean post-prandial glucose and insulin responses, respectively; mean incremental areas under the curve for glucose and insulin, respectively, were 64.3±21.8 (mmol/l/240 min; P<0.01) and 2253±539 (μU/ml/240 min; P<0.01) lower following the low- compared with the high-GL test meal. There was no effect of GL on mean homeostasis model assessment for insulin resistance or on mean integrated post-prandial concentrations of glucose-adjusted insulin, IGF-1 or IGFBP-3. We did not observe modification of the dietary effect by adiposity. CONCLUSIONS Low-GL diets resulted in 43% and 27% lower post-prandial responses of glucose and insulin, respectively, and modestly lower fasting IGF-1 concentrations. Further intervention studies are needed to weigh the impact of dietary GL on risk for chronic disease.