LIPGENE food-exchange model for alteration of dietary fat quantity and quality in free-living participants from eight European countries

Abstract

Controlled human intervention trials are required to confirm the hypothesis that dietary fat quality may influence insulin action. The aim was to develop a food-exchange model, suitable for use in free-living volunteers, to investigate the effects of four experimental diets distinct in fat quantity and quality: high SFA (HSFA); high MUFA (HMUFA) and two low-fat (LF) diets, one supplemented with 1·24 g EPA and DHA/d (LFn-3). A theoretical food-exchange model was developed. The average quantity of exchangeable fat was calculated as the sum of fat provided by added fats (spreads and oils), milk, cheese, biscuits, cakes, buns and pastries using data from the National Diet and Nutrition Survey of UK adults. Most of the exchangeable fat was replaced by specifically designed study foods. Also critical to the model was the use of carbohydrate exchanges to ensure the diets were isoenergetic. Volunteers from eight centres across Europe completed the dietary intervention. Results indicated that compositional targets were largely achieved with significant differences in fat quantity between the high-fat diets (39·9 (SEM 0·6) and 38·9 (SEM 0·51) percentage energy (%E) from fat for the HSFA and HMUFA diets respectively) and the low-fat diets (29·6 (SEM 0·6) and 29·1 (SEM 0·5) %E from fat for the LF and LFn-3 diets respectively) and fat quality (17·5 (SEM 0·3) and 10·4 (SEM 0·2) %E from SFA and 12·7 (SEM 0·3) and 18·7 (SEM 0·4) %E MUFA for the HSFA and HMUFA diets respectively). In conclusion, a robust, flexible food-exchange model was developed and implemented successfully in the LIPGENE dietary intervention trial.

Dietary fat modifies lipid metabolism in the adipose tissue of metabolic syndrome patients

“…Metabolic syndrome (MetS) patients, according to published criteria (Grundy et al 2004), were randomly stratified to 1 of 4 dietary interventions (isoenergetic diets) for 12 week, which conformed to the LIPGENE inclusion and exclusion criteria (Shaw et al 2009). Post-intervention, a fat challenge (test meal) was administered providing the same amount of fat (0.7 g/kg body weight), wherein the fatty acid composition reflected that consumed within the intervention period.…”

“…Post-intervention, a fat challenge (test meal) was administered providing the same amount of fat (0.7 g/kg body weight), wherein the fatty acid composition reflected that consumed within the intervention period. The intervention study design and intervention protocol, which also provides information about food consumption and dietary compliance have been described in detail by Shaw et al (2009). Briefly, dietary intake and compliance were assessed by a 3-day (2 weekdays and 1 weekend day) weighed food intake assessments at baseline, week 6, and week 12.…”

“…Randomization and intervention have been previously described in detail (Meneses et al 2011;Shaw et al 2009). Briefly, randomization was completed according to age, gender, and fasting plasma glucose concentration.…”

SATgenɛ dietary model to implement diets of differing fat composition in prospectively genotyped groups (apoE) using commercially available foods

“…Food exchange model to achieve dietary targets A food exchange model based on the National Diet and Nutrition Survey of UK adults aged 19 -64 years (10) was developed from a method used in previously published strategies from our group (7,8) . This served to establish that the composition of the three different diets was achievable within a freeliving UK population using commercially available products ( Table 1).…”

“…This facilitated the implementation of specific fat manipulation without confounding effects of other dietary changes. Dietary strategies developed within our group have been published previously using specially formulated products to achieve specific dietary fatty acid compositions (7,8) . These strategies have been adapted for the SATgen1 study in which only commercially available products were used as intervention foods.…”