A pilot, randomized, placebo-controlled study of mindfulness meditation in treating insomnia in multiple sclerosis.

OBJECTIVE: Mindfulness is an established approach to reduce distress and stress reactivity by improving awareness and tolerability of thoughts and emotions. This study compares mindfulness training to sleep hygiene in persons with multiple sclerosis (PWMS) who report chronic insomnia, examining sleep efficiency (SE), self-reported sleep quality and quality of life. METHODS: Fifty-three PWMS were randomized (1:1) in a single-blinded, parallel group design to ten, two-hour weekly sessions of Mindfulness Based Stress Intervention for Insomnia (MBSI-I) over a span of ten weeks or a single, one hour sleep hygiene (SH) session over one day. The primary outcome measure was SE, measured by the Fitbit™ Charge 2 wrist device, at 10 and 16 weeks from the start of study interventions. Self-report outcomes included the Pittsburg Sleep Quality Rating Scale (PSQI), Insomnia Severity Index (ISI) and the Multiple Sclerosis Quality of Life Inventory (MSQLI). Nineteen participants in the MBSI-I group and 24 in the SH group completed the primary study. Subsequently, ten participants in the original SH group participated in the 10-week MSBI-I course and their data was added to the MBSI-I cohort (eMSBI-I). RESULTS: While neither SE nor the PSQI showed significant differences between MBSI-I, eMBSI-I and SH groups, ISI improved in both the MSBI-I and eMBSI-I vs SH at 10 weeks (p = 0.0014 and p = 0.0275) but not 16 weeks. However, pre and post assessments within the MBSI-I and eMBSI-I cohorts did show significant improvement in the PSQI and ISI at 10 and 16 weeks, while SH was significant in the ISI only at 16 weeks. Several quality of life measurements, including fatigue, mental health and cognitive function favored the mindfulness cohorts. CONCLUSION: This pilot study demonstrates beneficial effects of MBSR on insomnia, sleep quality and quality of life in PWMS. TRIAL REGISTRATION: NCT03949296. 14 May 2019.

Egg Consumption in the Context of Plant-Based Diets and Diet Quality in Adults at Risk for Type 2 Diabetes: A Randomized Single Blind Cross-over Controlled Trial.

Lifestyle changes that emphasis on plant-based diets (PBD) are typically recommended for those at risk for type 2 diabetes mellitus (T2DM) to mitigate their cardo-metabolic risk. We examined the impact of the inclusion of eggs compared with their exclusion from PBD on diet quality among adults at risk for T2DM.This was a randomized, controlled, single-blind, crossover trial of 35 adults (mean age 60.7 years; 25 women, 10 men; 34 Caucasians, 1 African-American) at risk for T2DM (i.e., pre- diabetes or metabolic syndrome) assigned to one of two possible sequence permutations of two treatments (PBD with eggs and exclusively PBD), with a 4-week washout period. Participants received dietary counseling from a dietitian to exclude or to include 2 eggs daily in the context of PBD for a 6-week period. Diet quality was assessed using the Healthy Eating Index 2015 (HEI-2015) at baseline and 6 weeks.Compared with the exclusion of eggs, the inclusion of eggs in the context of PBD improved the diet quality score for intake of total protein foods (1.0 ± 1.1 vs. -0.4 ± 1.0; p <.0001); seafood and plant proteins (0.2 ± 1.2 vs. -0.4 ± 1.1; p = 0.0338); and fatty acids (0.8 ± 2.5 vs. -0.7 ± 2.7; p = 0.0260). Overall diet quality score depreciated with the adoption of exclusively PBD without eggs (-3.1 ± 8.3; p = 0.0411), while it was unaffected with the adoption of a PBD with the inclusion of eggs (-0.6 ± 7.9; p = 0.6892).Eggs could be used as an adjuvant to enhance the diet quality among those at risk for T2DM who adopt plant-based dietary patterns.

Egg Consumption in the Context of Plant-Based Diets and Cardiometabolic Risk Factors in Adults at Risk of Type 2 Diabetes.

BACKGROUND: Plant-based diets (PBDs) are typically recommended to those at risk of type 2 diabetes mellitus (T2DM). OBJECTIVES: We examined how including eggs, compared with excluding them from PBDs, affected cardiometabolic risk factors in adults at risk of T2DM. METHODS: This was a randomized, controlled, single-blind, crossover trial of 35 adults (mean age: 60.7 y; 25 women, 10 men) at risk of T2DM assigned to 1 of 2 sequence permutations of 2 dietary treatments (plant-based plus eggs, and exclusively plant-based), with a 4-wk washout period. A dietitian counseled participants to exclude or include 2 eggs daily in the context of PBDs for a 6-wk interval. Our primary outcome measure was endothelial function (EF) measured as flow-mediated dilatation. Secondary outcome measures included lipid profile, blood pressure, insulin sensitivity, anthropometry, and dietary intake. Data were analyzed using generalized linear models. RESULTS: Compared with egg exclusion, egg inclusion in the context of PBDs did not adversely affect EF (-1.7% ± 6.5% compared with -1.8% ± 7.5%; P = 0.9805). Likewise, egg inclusion, compared with egg exclusion, did not adversely affect (P = 0.1096-0.9781) lipid profile, blood pressure, insulin sensitivity, or anthropometry. Egg inclusion, compared with egg exclusion, improved reported intakes of selenium (23.1 ± 30.3 µg/d compared with 2.3 ± 34.9 µg/d; P = 0.0124) and choline (172.0 ± 96.0 mg/d compared with -3.4 ± 68.1 mg/d; P < 0.0001). CONCLUSIONS: Consuming 2 eggs daily in the context of PBDs does not adversely affect cardiometabolic risk factors among adults at risk of T2DM. Eggs could be used as an adjuvant to enhance PBDs that are typically recommended for those at risk of T2DM.This trial was registered at clinicaltrials.gov as NCT04316429.

Post-prandial effects of high-polyphenolic extra virgin olive oil on endothelial function in adults at risk for type 2 diabetes: A randomized controlled crossover trial.

BACKGROUND: Effects of olive oil on cardiovascular risk have been controversial. We compared the effects of high-polyphenolic extra virgin olive oil (EVOO) and refined olive oil without polyphenols on endothelial function (EF) in adults at risk for Type 2 diabetes mellitus (T2DM). METHODS: Randomized, controlled, double-blind, crossover trial of 20 adults (mean age 56.1 years; 10 women, 10 men) at risk for T2DM (i.e., as defined by either prediabetes or metabolic syndrome) assigned to one of two possible sequence permutations of two different single dose treatments (50 mL of high-polyphenolic EVOO or 50 mL of refined olive oil without polyphenols), with 1-week washout. Participants received their olive oils in a smoothie consisting of ½ cup frozen blueberries and 1 cup (8 oz) low-fat vanilla yogurt blended together. Primary outcome measure was EF measured as flow-mediated dilatation. Participants were evaluated before and 2 h after ingestion of their assigned olive oil treatment. RESULTS: EVOO acutely improved EF as compared to refined olive oil (1.2 ± 6.5% versus -3.6 ± 3.8%; p = 0.0086). No significant effects on systolic or diastolic blood pressure were observed. CONCLUSIONS: High-polyphenolic EVOO acutely enhanced EF in the study cohort, whereas refined olive oil did not. Blood pressure effects were not observed. Reports on the vascular effects of olive oil ingestion should specify the characteristics of the oil. CLINICAL TRIAL REGISTRATION NUMBER: NCT04025281.

Snacking, Satiety, and Weight: A Randomized, Controlled Trial.

PURPOSE: To compare the effects of nut-based snack bars (NBSB) vs. prepackaged 200-kcal portions of typical conventional snack foods, when consumed over a 12-week period by a group of overweight adults. DESIGN: Randomized, single-blind parallel design with two treatment groups. SUBJECTS: Thirty-four overweight participants were enrolled. INTERVENTION: Commercially available NBSB or conventional snack foods as part of an ad libitum diet for 12 weeks. PRIMARY OUTCOME MEASURES: body mass index, body weight, body composition, waist circumference. SECONDARY OUTCOME MEASURES: blood pressure, lipid profile, nutrients intake, hunger/satiety, quality of life. ANALYSIS: Generalized linear models with time as repeated measure were used to analyze these data. RESULTS: Daily consumption of NBSB for 12 weeks, as compared to daily consumption of conventional snacks, significantly reduced percentage body fat (-1.7% ± 10.8% vs. 6.2% ± 9.3%; p = .04) and visceral fat (-1.3 ± 5.9 vs. 2.7 ± 4.0; p = .03). There were no between-group differences (p > .05) for blood pressure, lipid panel, satiety, or quality of life measures. CONCLUSION: Our data suggest that daily consumption of NBSB for 12 weeks reduced body fat and had no adverse effects on weight, blood pressure, lipid profile, satiety, or quality of life in this small sample of overweight adults.

Advancing School and Community Engagement Now for Disease Prevention (ASCEND).

PURPOSE: To compare two intensity levels (standard vs. enhanced) of a nutrition and physical activity intervention vs. a control (usual programs) on nutrition knowledge, body mass index, fitness, academic performance, behavior, and medication use among elementary school students. DESIGN: Quasi-experimental with three arms. SETTING: Elementary schools, students' homes, and a supermarket. SUBJECTS: A total of 1487 third-grade students. INTERVENTION: The standard intervention (SI) provided daily physical activity in classrooms and a program on making healthful foods, using food labels. The enhanced intervention (EI) provided these plus additional components for students and their families. MEASURES: Body mass index (zBMI), food label literacy, physical fitness, academic performance, behavior, and medication use for asthma or attention-deficit hyperactivity disorder (ADHD). ANALYSIS: Multivariable generalized linear model and logistic regression to assess change in outcome measures. RESULTS: Both the SI and EI groups gained less weight than the control (p < .001), but zBMI did not differ between groups (p = 1.00). There were no apparent effects on physical fitness or academic performance. Both intervention groups improved significantly but similarly in food label literacy (p = .36). Asthma medication use was reduced significantly in the SI group, and nonsignificantly (p = .10) in the EI group. Use of ADHD medication remained unchanged (p = .34). CONCLUSION: The standard intervention may improve food label literacy and reduce asthma medication use in elementary school children, but an enhanced version provides no further benefit.

Inclusion of walnut in the diets of adults at risk for type 2 diabetes and their dietary pattern changes: a randomized, controlled, cross-over trial.

BACKGROUND: In our recently published study, including walnuts in the diets of adults with prediabetes led to overall improvement in diet quality. This report adds to those study findings by examining the food groups displaced during walnut inclusion in the diets of those adults with prediabetes. METHODS: Randomized, controlled, modified Latin square parallel design with 2 treatment arms. The 112 participants (31 men, 81 women) were randomly assigned to a diet with or without dietary counseling to regulate calorie intake in a 1:1 ratio. Within each treatment arm, participants were further randomized to 1 of 2 sequence permutations to receive a walnut-included diet with 56 g (366 kcal) of walnuts per day and a walnut-excluded diet. Participants in the calorie-regulated arm received advice from a dietitian to preserve an isocaloric condition while including walnuts. We analyzed the 12 components of the 2010 Healthy Eating Index to examine dietary pattern changes of study participants. RESULTS: Seafood and plant protein foods intake significantly increased with walnut inclusion, compared with their exclusion (2.14±2.06 vs -0.49±2.33; p=0.003). The ingestion of healthful fatty acids also significantly increased with walnut inclusion, compared with their exclusion (1.43±4.53 vs -1.76±4.80; p=0.02). Dairy ingestion increased with walnut inclusion in the calorie-regulated phase, compared with walnut inclusion without calorie regulation (1.06±4.42 vs -2.15±3.64; p=0.02). CONCLUSIONS: Our data suggest that walnut inclusion in the diets of adults at risk for diabetes led to an increase in intake of other healthful foods. TRIAL REGISTRATION NUMBER: NCT02330848.

Egg ingestion in adults with type 2 diabetes: effects on glycemic control, anthropometry, and diet quality-a randomized, controlled, crossover trial.

BACKGROUND: The inclusion of eggs as part of a healthful diet for adults with diabetes is controversial. We examined the effects of including eggs in the diet of adults with type 2 diabetes on cardiometabolic risk factors. METHODS: Randomized, controlled, single-blind, crossover trial of 34 adults (mean age 64.5 years; 14 postmenopausal women, 20 men) with type 2 diabetes assigned to one of two possible sequence permutations of two different 12-week treatments (two eggs/day inclusion or egg exclusion), with 6-week washout periods. For the egg inclusion phase, participants received advice from a dietitian on how to preserve an isocaloric condition relative to the egg exclusion phase. The primary outcome was glycemic control as measured by glycated hemoglobin. Secondary measures included anthropometry, blood pressure, and diet quality. RESULTS: Compared with the exclusion of eggs in the habitual diet, the inclusion of eggs did not measurably affect glycated hemoglobin (0.01±0.5% vs -0.24±0.7%; p=0.115) and systolic blood pressure (-0.8±13.0 vs -3.0±10.0 mm Hg; p=0.438); and significantly reduced body mass index (0.06±0.8 vs -0.4±0.8 kg/m²; p=0.013) and visceral fat rating (0.2±1.1 vs -0.4±1.0; p=0.016). The inclusion of eggs in the habitual diet of diabetics significantly reduced waist circumference (-0.4±1.2 cm; p=0.004) and percent body fat (-0.7±1.8; p=0.033) from baseline. CONCLUSIONS: Short-term daily inclusion of eggs in the habitual diet of adults with type 2 diabetes does not improve glycemic control but can improve anthropometric measures. TRIAL REGISTRATION NUMBER: NCT02052037; results.

Walnut ingestion in adults at risk for diabetes: effects on body composition, diet quality, and cardiac risk measures.

BACKGROUND: Despite their energy density, walnuts can be included in the diet without adverse effects on weight or body composition. The effect of habitual walnut intake on total calorie intake is not well studied. Effects on overall diet quality have not been reported. METHODS: Randomized, controlled, modified Latin square parallel design study with 2 treatment arms. The 112 participants were randomly assigned to a diet with or without dietary counseling to adjust calorie intake. Within each treatment arm, participants were further randomized to 1 of the 2 possible sequence permutations to receive a walnut-included diet with 56 g (providing 366 kcal) of walnuts per day and a walnut-excluded diet. Participants were assessed for diet quality, body composition, and cardiac risk measures. RESULTS: When compared with a walnut-excluded diet, a walnut-included diet for 6 months, with or without dietary counseling to adjust caloric intake, significantly improved diet quality as measured by the Healthy Eating Index 2010 (9.14±17.71 vs 0.40±15.13; p=0.02 and 7.02±15.89 vs -5.92±21.84; p=0.001, respectively). Endothelial function, total and low-density lipoprotein (LDL) cholesterol improved significantly from baseline in the walnut-included diet. Body mass index, percent body fat, visceral fat, fasting glucose, glycated hemoglobin, and blood pressure did not change significantly. CONCLUSIONS: The inclusion of walnuts in an ad libitum diet for 6 months, with or without dietary counseling to adjust calorie intake, significantly improved diet quality, endothelial function, total and LDL cholesterol, but had no effects on anthropometric measures, blood glucose level, and blood pressure. TRIAL REGISTRATION NUMBER: NCT02330848.

Promoting Healthy Lifestyles to Children at School: Using a Multidisciplinary Train-the-Trainer Approach.

OBJECTIVE: The purpose of the study was to examine the efficacy of a multidisciplinary train-the-trainer model for improving fitness and food label literacy in third-grade students. DESIGN: University student trainers taught ABC for Fitness and Nutrition Detectives, established programs to promote physical activity and nutrition knowledge, to 239 third-grade students in 2 communities over a 6-month period. A total of 110 children were in the intervention group and 129 children in the control group (2 schools each). Outcomes included the Food Label Literacy and Nutrition Knowledge test and the fitness measures of curl-ups, push-ups, 0.5-mile run, and sit and reach. Focus groups were conducted as process feedback. SETTING: Four public schools in 2 different communities. PARTICIPANTS: A total of 200 third-grade students. INTERVENTION: ABC for Fitness and Nutrition Detectives. MAIN OUTCOME MEASURES: Food Label Literacy and Nutrition Knowledge test and the fitness measures of curl-ups, push-ups, 0.5-mile run, and sit and reach. RESULTS: Nutrition knowledge increased in the intervention group by 25.2% (P < .01). Fitness measures in the intervention schools showed greater improvement than those in the controls for curl-ups (P < .01), push-ups (P < .01), sit and reach left (P = .07), and 0.5-mile run (P = .06). Process feedback from 3 teachers and 60 students indicated satisfaction with the program. CONCLUSION: Adaptation of the train-the-trainer approach for Nutrition Detectives and ABC for Fitness was effective for delivering these health-related programs.

Effects of egg ingestion on endothelial function in adults with coronary artery disease: a randomized, controlled, crossover trial.

BACKGROUND: Prevailing recommendations call for restricting intake of dietary cholesterol and eggs for those at risk of heart disease, despite accumulating evidence challenging this association. Our prior studies showed no short-term adverse effects of daily egg intake on cardiac risk factors in at-risk adults. OBJECTIVE: We conducted this study to determine effects of daily egg consumption in adults with established coronary artery disease (CAD). METHODS: Randomized, controlled, single-blind, crossover trial of 32 adults (mean age, 67 years; 6 women, 26 men) with CAD assigned to 1 of 6 possible sequence permutations of 3 different treatments (breakfast with 2 eggs, breakfast with ½ cup Egg Beaters, ConAgra Foods, St. Louis, MO, or a high-carbohydrate breakfast part of an ad libitum diet) for 6 weeks, with 4-week washout periods. The primary outcome measure was endothelial function measured as flow-mediated dilatation. RESULTS: Compared with the control breakfast (ie, high-carbohydrate breakfast), daily consumption of eggs showed no adverse effects on flow-mediated dilatation (7.2% ± 2.9% vs 7.5% ± 2.9%, P = .33), lipids (total cholesterol: 158.3 ± 28.6 mg/dL vs 156.2 ± 27.4 mg/dL, P = .49), blood pressure (systolic blood pressure: 132.8 ± 14.1 mm Hg or vs 135.5 ± 14.9 mm Hg, P = .52; diastolic blood pressure: 77.2 ± 6.1 mm Hg vs 76.7 ± 6.9 mm Hg, P = .86), or body weight (90.8 ± 17.5 kg vs 91.8 ± 17.1 kg, P = .92). No outcomes differed (P > .05) between eggs and Egg Beaters. CONCLUSIONS: We found no evidence of adverse effects of daily egg ingestion on any cardiac risk factors in adults with CAD over a span of 6 weeks.

Testing the effectiveness of an abbreviated version of the Nutrition Detectives program.

INTRODUCTION: Obese or overweight children have an increased risk for chronic diseases. Targeting diet and exercise in schools could help prevent childhood obesity. We have previously shown the effectiveness of a 90-minute nutrition program in improving elementary school students' food-label literacy. The objective of this study was to investigate the effectiveness of a 45-minute version of the program. METHODS: We conducted a pre-post study in a public school district, with no control group. We provided teacher training and program materials. Participants were 5th-grade students in 5 schools who had parental consent and were willing to take part. We condensed the program to a 45-minute lesson with a presentation and hands-on activity. The lesson showed students why and how to make healthful food choices based on Nutrition Facts panels and ingredient lists. The district's physical education teachers taught the lesson. The primary outcome measure was food-label literacy (ie, the ability to distinguish between more and less healthful foods using a validated test instrument with Nutrition Facts panels and ingredient lists). RESULTS: A total of 212 students completed pre-post measures. Following program delivery, we observed a significant gain of 16.2 percentage points in scores overall, ranging from 4.3 percentage points to 23.6 percentage points among schools. Results were similar to those achieved with the 90-minute program. DISCUSSION: The condensed nutrition program improved students' food-label literacy while requiring a minimal allocation of time. Further studies in other school districts would be useful.

The validation of a food label literacy questionnaire for elementary school children.

OBJECTIVE: To determine the reliability and validity of a 10-item questionnaire, the Food Label Literacy for Applied Nutrition Knowledge questionnaire. METHODS: Participants were elementary school children exposed to a 90-minute school-based nutrition program. Reliability was assessed via Cronbach α and intraclass correlation coefficient (ICC). Validity was assessed comparing the questionnaire's food choices using an objective metric of nutrition quality, the Overall Nutritional Quality Index (ONQI), via t test. Statistical significance was set at .05. RESULTS: Four hundred ninety-nine children participated, 51% were female, and the average age was 8.6 (± 0.9) years. Cronbach α = .77 and ICC = 0.68 (between administrations) were observed. ONQI scores of correct responses were significantly higher when compared to the ONQI scores of incorrect responses (27.4 ± 9.4 vs 16.2 ± 9.4; P = .01). CONCLUSIONS AND IMPLICATIONS: The Food Label Literacy for Applied Nutrition Knowledge questionnaire was found to be both reliable and a valid measure of food label literacy in children taught the Nutrition Detectives program.

A cost comparison of more and less nutritious food choices in US supermarkets.

OBJECTIVE: The present study directly compared prices of more and less nutritious foods within given categories in US supermarkets. DESIGN: Foods selected from six supermarkets in Jackson County were categorized using the five criteria of the Nutrition Detectives™ (ND) programme and an item-to-item cost comparison was made using posted prices. The nutritional quality of foods was distinguished using the clues of the ND nutrition education programme for elementary-school children and validated using the Overall Nutritional Quality Index. SETTING: Supermarkets in Jackson County, MO, USA. SUBJECTS: Not applicable. RESULTS: The average price of the item for more nutritious foods did not differ significantly from that of less nutritious foods overall ($US 2·89 (sd $US 0·74) v. $US 2·85 (sd $0·68), P = 0·76). More nutritious breads cost more than less nutritious breads ($US 3·36 (sd $ US 0·28) v. $US 2·56 (sd $US 0·80, P = 0·03), whereas more nutritious cereals ($US 2·46 (sd $US 0·69) v. $US 3·50 (sd $US 0·30), P < 0·01) and cookies ($US 2·76 (sd $US 0·50) v. $US 3·40 (sd $US0·28), P < 0·01) cost less. CONCLUSIONS: Our findings indicate that it is possible to choose more nutritious foods within many common categories without spending more money and suggest that making small improvements in dietary choices does not invariably cost more.

Teaching healthful food choices to elementary school students and their parents: the Nutrition Detectives™ program.

BACKGROUND: The purpose of this study was to evaluate the effects of a nutrition education program designed to teach elementary school students and their parents, and to distinguish between more healthful and less healthful choices in diverse food categories. METHODS: Three schools were assigned to receive the Nutrition Detectives™ program and 2 comparable schools served as controls. A total of 1180 second, third, and fourth grade elementary school students were included, with 628 students in the intervention and 552 in the control group. The program, delivered by physical education instructors over several sessions totaling less than 2 hours, taught the children how to read food labels and detect marketing deceptions, while learning to identify and choose healthful foods. Parents were introduced to the program through written materials sent home and at school functions. Assessments included a food label quiz, dietary pattern, and body mass index (BMI). RESULTS: Students in intervention schools showed a significant increase in nutrition label literacy (p < .01). Third grade students showed the most improvement, 23% (p < .01). The parents of intervention group students also showed a significant increase in nutrition label literacy by 8% (p < .01). Total caloric, sodium, and total sugar intake decreased nonsignificantly among students in the intervention group (p > .05). BMI did not change over the short duration of the study. CONCLUSIONS: Nutrition Detectives effectively enhances the ability of students and their parents to identify more nutritious food choices. Further evaluation of the program and its potential to influence dietary pattern, BMI, and health outcomes in students and their families is warranted.

Putting physical activity where it fits in the school day: preliminary results of the ABC (Activity Bursts in the Classroom) for fitness program.

INTRODUCTION: Despite well-documented evidence that physical activity is beneficial to children, average fitness levels of US children have declined. Lack of physical activity has been associated with childhood obesity. We evaluated the effects of a physical activity program in the elementary school classroom on health outcomes. METHODS: Three schools in the Independence School District in Independence, Missouri, were assigned to receive the ABC (Activity Bursts in the Classroom) for Fitness program, and 2 comparable schools served as controls. The program, led by classroom teachers, provides multiple, brief, structured physical activity breaks throughout the day. Baseline data for the study were collected in September 2007, and follow-up data were collected in April 2008. RESULTS: Physical fitness measures of upper-body strength, abdominal strength, and trunk extensor improved (P <.001). Medication use for asthma (P = .03), attention-deficit hyperactivity disorder (P = .07), or either medication combined (P = .005) decreased. CONCLUSION: The effects of the program on daily physical activity, fitness, and measures of health are beneficial.

Effects of walnut consumption on endothelial function in type 2 diabetic subjects: a randomized controlled crossover trial.

OBJECTIVE: To determine the effects of daily walnut consumption on endothelial function, cardiovascular biomarkers, and anthropometric measures in type 2 diabetic individuals. RESEARCH DESIGN AND METHODS: This study was a randomized, controlled, single-blind, crossover trial. Twenty-four participants with type 2 diabetes (mean age 58 years; 14 women and 10 men) were randomly assigned to one of the two possible sequence permutations to receive an ad libitum diet enriched with 56 g (366 kcal) walnuts/day and an ad libitum diet without walnuts for 8 weeks. Subjects underwent endothelial function testing (measured as flow-mediated dilatation [FMD]) and assessment of cardiovascular biomarkers before and after each 8-week treatment phase. The primary outcome measure was the change in FMD after 8 weeks. Secondary outcome measures included changes in plasma lipids, A1C, fasting glucose, insulin sensitivity, and anthropometric measures. RESULTS: Endothelial function significantly improved after consumption of a walnut-enriched ad libitum diet compared with that after consumption of an ad libitum diet without walnuts (2.2 +/- 1.7 vs. 1.2 +/- 1.6%; P = 0.04). The walnut-enriched diet increased fasting serum glucose and lowered serum total cholesterol and LDL cholesterol from baseline (10.0 +/- 20.5 mg/dl, P = 0.04; -9.7 +/- 14.5 mg/dl, P < 0.01; and -7.7 +/- 10 mg/dl, P < 0.01, respectively), although these changes were not significant compared with those for an ad libitum diet without walnuts. There were no significant changes in anthropometric measures, plasma A1C, and insulin sensitivity. CONCLUSIONS: A walnut-enriched ad libitum diet improves endothelium-dependent vasodilatation in type 2 diabetic individuals, suggesting a potential reduction in overall cardiac risk.