BACKGROUND: Escalating rates of childhood obesity are likely to have an impact on the prevalence of coronary heart disease and type-2 diabetes. We aimed to identify barriers to healthy lifestyles and evaluate the effectiveness of an action research approach to lifestyle modification in secondary schools.
METHODS: An action research partnership between schools and university researchers involved pupils aged 11-15 in five inner-city secondary schools serving a predominantly South Asian population in Leicester, UK. Data collection included baseline and follow-up diet and physical activity questionnaires. Focus groups and observational visits were used to identify barriers, assist with developing tailored interventions and review the impact of the study.
RESULTS: Working with secondary schools presented challenges but a useful partnership was sustained. Qualitative feedback suggested that this had raised awareness of healthy lifestyle issues in participating schools. Barriers in pupils included low prioritization of health when making lifestyle choices. Sub-optimal diet and activity habits were identified at baseline. Overall, these persisted at follow-up, although some limited positive changes were identified.
CONCLUSIONS: Using action research methods in this context is challenging but can facilitate useful data collection and may have a modest impact on lifestyle behaviours.
CONTEXT: Risk factors for type 2 diabetes mellitus (T2DM) include obesity, family history, dyslipidemia, a proinflammatory state, impaired insulin secretory capacity, and insulin resistance.
OBJECTIVE: The aim of this study was to examine the effects of a 3- to 4-month school-based intervention consisting of health, nutrition, and exercise classes plus an aerobic exercise program on diabetes risk.
DESIGN: This study was a randomized before/after controlled trial.
METHODS: Seventy-three eighth-grade students in a predominantly Hispanic New York City public school were divided into a control group (studied twice without receiving the intervention) and an experimental group (studied before and after the intervention).
OUTCOME MEASURES: We measured body fatness (bioelectrical impedance), insulin sensitivity, beta-cell function (insulin release in response to an iv glucose load corrected for insulin sensitivity), lipid profiles, and circulating concentrations of IL-6, C-reactive protein, adiponectin, and TNF-alpha.
RESULTS: Participation in the intervention was associated with significant reductions in body fatness, insulin resistance, and circulating concentrations of C-reactive protein and IL-6, irrespective of somatotype on enrollment.
CONCLUSION: Short-term school-based health, nutrition, and exercise intervention is beneficial to all students and affects multiple diabetes risk factors.
The aim of this study was to evaluate the economic performance of 10 nutrition interventions. The interventions included Mediterranean Diet, Intensive Lifestyle Change (nutrition and physical activity) to Prevent Diabetes, Reduced Fat Diet for persons with IGT, Nutritional Counselling in GP (GP, general practice/primary care), Nurse Counselling in GP, Oxcheck Nurse Health Checks in GP, Gutbusters Workplace (for men), Talking Computer, Multi Media 2 fruit 5 veg Campaign and the FFFF (Fighting Fit, Fighting Fat) Media Campaign. Markov models were constructed in order to estimate economic performance expressed as cost per QALY (quality adjusted life year) gained. Data from original clinical trial reports were used to populate the models, supplemented by the wider literature where required. Performance of the Mediterranean Diet and Intensive Lifestyle Change to Prevent Diabetes interventions could be estimated with most certainty and both were highly cost-effective interventions, at AU $1020 (US $760, 410 pounds) and AU $1880 (US $1410, 750 pounds) per QALY gained, respectively. The media campaign interventions appear highly cost-effective at AU $46 (US $34, 18 pounds) for '2 fruit 5 veg' and AU $5600 (US $4200, 2200 pounds) per QALY gained for FFFF, but are associated with considerable uncertainty, and may be dominated under certain assumptions. Several interventions were cost-saving under plausible sets of assumptions, whereas a small number were potentially dominated. All interventions subject to economic evaluation appeared cost-effective relative to societal norms. Nutrition interventions can constitute a highly efficient component of a strategy to reduce the growing disease burden linked to over/poor nutrition. There is an urgent need for high-quality trial data from which economic performance of nutrition interventions can be modelled.
AIM: To evaluate the effectiveness of lifestyle interventions in people with impaired glucose tolerance (IGT). METHODS: Participants with IGT (n=78), diagnosed on two consecutive oral glucose tolerance tests (OGTTs), were randomly assigned to a 2-year lifestyle intervention or to a control group. Main outcome measures were changes from baseline in: nutrient intake; physical activity; anthropometry, glucose tolerance and insulin sensitivity. Measurements were repeated at 6, 12 and 24 months follow-up. RESULTS: After 24 months follow-up, there was a significant fall in total fat consumption (difference in change between groups (Delta intervention-Delta control)=-17.9, 95% confidence interval (CI) -33.6 to -2.1g/day) as a result of the intervention. Body mass was significantly lower in the intervention group compared with controls after 6 months (-1.6, 95% CI -2.9 to -0.4kg) and 24 months (-3.3, 95% CI -5.7 to -0.89kg). Whole body insulin sensitivity, assessed by the short insulin tolerance test (ITT), improved after 12 months in the intervention group (0.52, 95% CI 0.15-0.89%/min). CONCLUSIONS: These findings complement the findings of the Finnish Diabetes Prevention Study and the American Diabetes Prevention Study, both of which tested intensive interventions, by showing that pragmatic lifestyle interventions result in improvements in obesity and whole body insulin sensitivity in individuals with IGT, without change in other cardiovascular risk factors.
OBJECTIVE: Diabetes Prevention Program (DPP) participants randomized to the intensive lifestyle intervention (ILS) had significantly reduced risk of diabetes compared with placebo participants. We explored the contribution of changes in weight, diet, and physical activity on the risk of developing diabetes among ILS participants.
RESEARCH DESIGN AND METHODS: For this study, we analyzed one arm of a randomized trial using Cox proportional hazards regression over 3.2 years of follow-up.
RESULTS: A total of 1,079 participants were aged 25-84 years (mean 50.6 years, BMI 33.9 kg/m(2)). Weight loss was the dominant predictor of reduced diabetes incidence (hazard ratio per 5-kg weight loss 0.42 [95% CI 0.35-0.51]; P < 0.0001). For every kilogram of weight loss, there was a 16% reduction in risk, adjusted for changes in diet and activity. Lower percent of calories from fat and increased physical activity predicted weight loss. Increased physical activity was important to help sustain weight loss. Among 495 participants not meeting the weight loss goal at year 1, those who achieved the physical activity goal had 44% lower diabetes incidence.
CONCLUSIONS: Interventions to reduce diabetes risk should primarily target weight reduction.
AIMS/HYPOTHESIS: The aim of this study was to investigate the association of dietary macronutrient composition and energy density with the change in body weight and waist circumference and diabetes incidence in the Finnish Diabetes Prevention Study.
SUBJECTS AND METHODS: Overweight, middle-aged men (n=172) and women (n=350) with impaired glucose tolerance were randomised to receive either 'standard care' (control) or intensive dietary and exercise counselling. Baseline and annual examinations included assessment of dietary intake with 3-day food records and diabetes status by repeated 75-g OGTTs. For these analyses the treatment groups were combined and only subjects with follow-up data (n=500) were included.
RESULTS: Individuals with low fat (<median) and high fibre (>median) intakes lost more weight compared with those consuming a high-fat (>median), low-fibre (<median) diet (3.1 vs 0.7 kg after 3 years). In separate models, hazard ratios for diabetes incidence during a mean follow-up of 4.1 years were (highest compared with lowest quartile) 0.38 (95% CI 0.19-0.77) for fibre intake, 2.14 (95% CI 1.16-3.92) for fat intake, and 1.73 (95% CI 0.89-3.38) for saturated-fat intake, after adjustment for sex, intervention assignment, weight and weight change, physical activity, baseline 2-h plasma glucose and intake of the nutrient being investigated. Compared with the low-fat/high-fibre category, hazard ratios were 1.98 (95% CI 0.98-4.02), 2.68 (95% CI 1.40-5.10), and 1.89 (95% CI 1.09-3.30) for low-fat/low-fibre, high-fat/high-fibre, and high-fat/low-fibre, respectively.
CONCLUSIONS/INTERPRETATION: Dietary fat and fibre intake are significant predictors of sustained weight reduction and progression to type 2 diabetes in high-risk subjects, even after adjustment for other risk factors.
BACKGROUND: Lifestyle interventions can prevent the deterioration of impaired glucose tolerance to manifest type 2 diabetes, at least as long as the intervention continues. In the extended follow-up of the Finnish Diabetes Prevention Study, we assessed the extent to which the originally-achieved lifestyle changes and risk reduction remain after discontinuation of active counselling.
METHODS: Overweight, middle-aged men (n=172) and women (n=350) with impaired glucose tolerance were randomly assigned to intensive lifestyle intervention or control group. After a median of 4 years of active intervention period, participants who were still free of diabetes were further followed up for a median of 3 years, with median total follow-up of 7 years. Diabetes incidence, bodyweight, physical activity, and dietary intakes of fat, saturated fat, and fibre were measured.
FINDINGS: During the total follow-up, the incidence of type 2 diabetes was 4.3 and 7.4 per 100 person-years in the intervention and control group, respectively (log-rank test p=0.0001), indicating 43% reduction in relative risk. The risk reduction was related to the success in achieving the intervention goals of weight loss, reduced intake of total and saturated fat and increased intake of dietary fibre, and increased physical activity. Beneficial lifestyle changes achieved by participants in the intervention group were maintained after the discontinuation of the intervention, and the corresponding incidence rates during the post-intervention follow-up were 4.6 and 7.2 (p=0.0401), indicating 36% reduction in relative risk.
INTERPRETATION: Lifestyle intervention in people at high risk for type 2 diabetes resulted in sustained lifestyle changes and a reduction in diabetes incidence, which remained after the individual lifestyle counselling was stopped.
The Sandy Lake school-based diabetes prevention program is a culturally appropriate intervention for Ojibway-Cree students in the 3rd, 4th, and 5th grades. This paper reports the results of the program in changing dietary intake behaviors and related psychosocial factors. Physical activity results are not included. The study was a pretest/post-test, single-sample design conducted during the 1998-1999 school year. A total of 122 students completed all 4 measurements (anthropometry, 24-h dietary recall, and 2 questionnaires), at baseline and follow-up. There were significant increases (P < 0.0001) in dietary intention, dietary preference, knowledge, and dietary self-efficacy, and in the curriculum knowledge scale between baseline and follow-up. Intervention exposure was significantly associated with being in the highest category for knowledge about foods that were low in dietary fat [Medium Exposure odds ratio (OR): 3.4; P < 0.05; High Exposure OR: 6.4; P < 0.05], being in the highest category for dietary self-efficacy (Medium Exposure OR: 3.7; P < 0.05; High Exposure OR: 3.9; P < 0.1), being in the highest category for knowledge about curriculum concepts (Medium Exposure OR: 3.4; P < 0.05; High Exposure OR: 9.4: P < 0.01), and for having met the age + 5 g dietary fiber intake/d (Medium Exposure OR: 2.9; P < 0.1; High Exposure OR: 11.0; P < 0.01). Exposure to the intervention was not associated with dietary intent or the percentage of energy from dietary fat. This program was associated with improved knowledge and the psychosocial factors related to healthy eating and dietary fiber intake of students in a remote First Nations community.
PURPOSE: The purpose of this study was to evaluate a 12-week workplace e-mail intervention designed to promote physical activity and nutrition behavior.
DESIGN: A pre- and post-test design was conducted to compare the effects of e-mail messages between intervention and control groups.
SETTING: Five large workplaces in Alberta, Canada.
SUBJECTS: Employees with access to a personal e-mail address (N = 2121) were randomly assigned to an intervention (n = 1566) or a control group (n = 555).
INTERVENTION: Physical activity and nutrition messages were based on social-cognitive theories. The intervention group received one physical activity and one parallel nutrition message per week for 12 weeks. The control group received no weekly messages.
MEASURES: Each participant completed self-report measures of physical activity and nutrition related to knowledge, attitudes, and behaviors 1 week before (time 1) and 1 week after (time 2) the intervention.
RESULTS: The intervention group was more efficacious at time 2 on measures of self-efficacy, pros, cons, intentions, and behavior related to physical activity. This group also reported more favorable changes in practicing healthy eating, balancing food intake with activity level, cooking meals with techniques to reduce fat, and avoiding eating high-fat foods. Effect sizes for all significant differences were small.
CONCLUSION: E-mail is a promising mode of delivery for promoting physical activity and nutrition in the workplace. Further theoretically driven studies are needed.
AIMS: To study the long-term (1- and 2-year) effect of a lifestyle intervention on non-diabetic first-degree relatives of type 2 diabetic patients, i.e., the 1-year effect of diet versus diet and exercise in relation to a control group and the 2-year sustainability of these treatment effects. METHOD: Seventy-seven healthy first-degree relatives (men and women) between the ages of 25 and 55 were allocated to one of three groups: diet group (D), diet and exercise group (DE) and control group (C). For ethical reasons, after 1 year the control group began the intervention and were followed for another 2 years. Diet and physical activity counselling was based on current nutrition recommendations, including increased intake of fatty fish and low glycaemic index foods. The fatty acid composition of the erythrocyte membrane was studied as an objective measure of dietary change. Assessments included fasting insulin, 2-h insulin, oral glucose tolerance test (OGTT), anthropometry and blood lipid measurements. Groups D and DE received intensive follow-up through unannounced telephone interviews during the first 4 months. RESULTS: Dietary changes were significant at 1 year, and to a large degree sustained at 2 years. Adherence to advice regarding fat quality was confirmed through changes in the fatty acid composition of the erythrocyte membrane. The least active subjects in DE increased their physical activity (PA). At 1 year, group D showed a reduction in the ratio of LDL to HDL cholesterol (p=0.028) while group DE decreased their body weight by 2.7% (p<0.029) and increased HDL (p<0.037) versus controls. At 2 years, cholesterol levels (total, LDL and the ratio LDL/HDL) were reduced within group D and when compared to DE (p=0.022, 0.009, 0.035, respectively). Fasting insulin was reduced within group DE and when compared to group D (p=0.025). CONCLUSIONS: Positive changes in lifestyle, blood lipids and fasting insulin can be achieved and maintained in a non-diabetic population at risk of type 2 diabetes after 2 years.
Escalating rates of childhood obesity are likely to have an impact on the prevalence of coronary heart disease and type-2 diabetes. We aimed to identify barriers to healthy lifestyles and evaluate the effectiveness of an action research approach to lifestyle modification in secondary schools.
METHODS:
An action research partnership between schools and university researchers involved pupils aged 11-15 in five inner-city secondary schools serving a predominantly South Asian population in Leicester, UK. Data collection included baseline and follow-up diet and physical activity questionnaires. Focus groups and observational visits were used to identify barriers, assist with developing tailored interventions and review the impact of the study.
RESULTS:
Working with secondary schools presented challenges but a useful partnership was sustained. Qualitative feedback suggested that this had raised awareness of healthy lifestyle issues in participating schools. Barriers in pupils included low prioritization of health when making lifestyle choices. Sub-optimal diet and activity habits were identified at baseline. Overall, these persisted at follow-up, although some limited positive changes were identified.
CONCLUSIONS:
Using action research methods in this context is challenging but can facilitate useful data collection and may have a modest impact on lifestyle behaviours.
