Blood Lipid Responses Research Articles

Exercise raises high-density lipoprotein cholesterol in men after consumption of ground beef with a high but not low monounsaturated fatty acid–saturated fatty acid ratio

Exercise and diets with higher monounsaturated fatty acid (MUFA):saturated fatty acid (SFA) ratios are independently linked to improved blood lipid profiles, yet interactive effects in men have not been studied. We hypothesized that dietary ground beef with a high MUFA:SFA ratio (HR = 1.1) would augment the beneficial changes in the lipid profile induced by exercise compared to dietary ground beef with a lower MUFA:SFA ratio (LR = 0.71). Untrained men (n = 13, age = 35 ± 12 y, weight = 91.4 ± 14.2 kg, body mass index = 27.8 ± 3.3kg/m2) consumed 5 HR or LR 114 g ground beef patties weekly for 5 weeks (random order) interspersed with a 4-week self-selected (SS) washout diet. One session of exercise (70% VO2max, 1675 kJ) was completed at the end of HR and LR diets, and again after a 5-week SS diet. Diets and physical activity were otherwise not controlled. Fasting blood samples for lipid and lipoprotein analyses were obtained 30 min before and 24 h after exercise. Subjects reported no other changes in diets or physical activity patterns, and body weight and body mass index did not change over the study duration. Diet (3) × Exercise Time (2) repeated measures analysis of variance (α = .05) and follow-up analyses revealed that blood concentrations (mmol/L ± SD) of total cholesterol (5.07 ± 1.16 to 5.73 ± 1.36), high-density lipoprotein cholesterol (HDL-C) (1.19 ± 0.20 to 1.36 ± 0.29), HDL2-C (0.24 ± 0.08 to 0.28 ± 0.11), HDL3-C (0.94 ± 0.14 to 1.08 ± 0.20), and non-HDL-C (3.88 ± 1.24 to 4.37 ± 1.38) were significantly elevated with exercise after the HR beef diet, but not after LR and SS diets. Thus, in healthy, untrained men the dietary beef MUFA:SFA ratio affects the blood lipid response to a single session of aerobic exercise.

A family-specific linkage analysis of blood lipid response to fenofibrate in the Genetics of Lipid Lowering Drug and Diet Network.

Cost-effective identification of novel pharmacogenetic variants remains a pressing need in the field. Using data from the Genetics of Lipid Lowering Drugs and Diet Network, we identified genomic regions of relevance to fenofibrate response in a sample of 173 families. Our approach included a multipoint linkage scan, followed by selection of the families showing evidence of linkage. We identified a strong signal for changes in LDL-cholesterol (LDL-C) on chromosome 7 (peak logarithm of odds score = 4.76) in the full sample (n = 821). The signal for LDL-C response remained even after adjusting for baseline LDL-C. Restricting analyses only to the families contributing to the linkage signal for LDL-C (N = 19), we observed a peak logarithm of odds score of 5.17 for chromosome 7. Two genes under this peak (ABCB4 and CD36) were of biological interest. These results suggest that linked family analyses might be a useful approach to gene discovery in the presence of a complex (e.g. multigenic) phenotype.

Changes in body composition and use of blood cholesterol lowering drugs predict changes in blood lipids during 12 weeks of resistance exercise training in old adults

Aging is associated with an impairment of blood lipids. The present study investigated the response of blood lipids to resistance exercise in old adults. The particular aim was to investigate whether the response of blood lipids is associated with changes in body composition of blood lipid medication. Subjects (N = 236, 73.7 ± 5.7 years, 58.2 % female) participated in a 12-week resistance exercise program (3 times/week; 3 sets, 6-8 repetitions at 75-80 % of the 1-repetition maximum), designed to increase strength and muscle mass of major muscle groups. Body composition, drug use, triglycerides (TG), total cholesterol (TC), low-density lipoprotein (LDL) and high-density lipoprotein (HDL) were assessed at baseline and endpoint. The concentrations of HDL (-6 mg/dl), LDL (-18 mg/dl), TC (-26 mg/dl) and TG (-12 mg/g) decreased significantly during the study period. A reduction in fat mass by 1 kg predicted a reduction in TG (5.0 mg/dl, P = 0.017) and a gain in lean body mass by 1 kg predicted also a reduction in TG (-4.5 mg/dl, P = 0.023). The use of blood cholesterol lowering drugs predicted greater reductions in TC (-16.9 mg/dl, P = 0.032) and LDL (-11.8 mg/dl, P = 0.038) during training. TG, TC, LDL and HDL decreased significantly after 12 weeks of progressive resistance exercise in old adults. Changes in body composition, i.e., reduction in fat mass and gain in lean body mass improved the blood lipid profile. Use of blood lipid lowering drugs was associated with greater reductions in TC and LDL after the training.

Consumption of low-fat dairy foods for 6 months improves insulin resistance without adversely affecting lipids or bodyweight in healthy adults: a randomized free-living cross-over study

BackgroundGiven the highly debated role of dairy food consumption in modulating biomarkers of metabolic syndrome, this study was conducted to examine the influence of long-term (6 month) dairy consumption on metabolic parameters in healthy volunteers under free-living conditions without energy restriction.MethodsTwenty-three healthy subjects completed a randomized, crossover trial of 12 months. Participants consumed their habitual diets and were randomly assigned to one of two treatment groups: a high dairy supplemented group instructed to consume 4 servings of dairy per day (HD); or a low dairy supplemented group limited to no more than 2 servings of dairy per day (LD). Baseline, midpoint, and endpoint metabolic responses were examined.ResultsEndpoint measurements of body weight and composition, energy expenditure, blood pressure, blood glucose, and blood lipid and lipoprotein responses did not differ (p > 0.05) between the LD and HD groups. HD consumption improved (p < 0.05) plasma insulin (-9%) and insulin resistance (-11%, p = 0.03) as estimated by HOMA-IR compared with the LD group.ConclusionsStudy results suggest that high dairy consumption (4 servings/d) may improve insulin resistance without negatively impacting bodyweight or lipid status under free-living conditions.Trial registrationTrial registration: NCT01761955

Influence of SNPs in nutrient-sensitive candidate genes and gene–diet interactions on blood lipids: the DiOGenes study

Blood lipid response to a given dietary intervention could be determined by the effect of diet, gene variants or gene-diet interactions. The objective of the present study was to investigate whether variants in presumed nutrient-sensitive genes involved in lipid metabolism modified lipid profile after weight loss and in response to a given diet, among overweight European adults participating in the Diet Obesity and Genes study. By multiple linear regressions, 240 SNPs in twenty-four candidate genes were investigated for SNP main and SNP-diet interaction effects on total cholesterol, LDL-cholesterol, HDL-cholesterol and TAG after an 8-week low-energy diet (only main effect) ,and a 6-month ad libitum weight maintenance diet, with different contents of dietary protein or glycaemic index. After adjusting for multiple testing, a SNP-dietary protein interaction effect on TAG was identified for lipin 1 (LPIN1) rs4315495, with a decrease in TAG of 20.26 mmol/l per A-allele/protein unit (95% CI 20.38, 20.14, P=0.000043). In conclusion, we investigated SNP-diet interactions for blood lipid profiles for 240 SNPs in twenty-four candidate genes, selected for their involvement in lipid metabolism pathways, and identified one significant interaction between LPIN1 rs4315495 and dietary protein for TAG concentration.

Acute glycemic and blood lipid response to the ingestion of a candy bar–like protein supplement compared with its candy bar counterpart

Candy bar-like protein supplements are sometimes consumed for their sugar alcohol content, which lowers the glycemic response. The purpose of this study was to determine the acute glycemic and blood lipid response to the ingestion of a candy bar-like protein supplement compared with its candy bar counterpart. In a crossover design, 5 males and 5 females (N = 10; age, 24 ± 5.5 years; height, 174 ± 8.3 cm; weight, 80 ± 21.9 kg) consumed a candy bar (CBR) or a similar protein bar (PBR) after a 10-h fast. Blood draws occurred at baseline and at 15, 30, 45, and 60 min after consumption and were analyzed for blood glucose, insulin, and lipid profiles. A 2×5 ANOVA was used, with Student's t tests for significant interactions. A significant (p < 0.05) blood glucose time effect occurred in both groups, with a more profound glucose response from the CBR at 15 min (CBR: 6.2 ± 0.8 mmol·L(-1); PBR: 4.9 ± 0.5 mmol·L(-1)). Triglycerides increased significantly (p < 0.05), independent of group, peaking at 60 min (Δ CBR: 0.8 ± 0.3 mmol·L(-1); Δ PBR: 1.3 ± 0.3 mmol·L(-1)). Insulin increased significantly (p < 0.05), independent of group, peaking at 15 min (Δ CBR: 42 ± 27 μIU·mL(-1); Δ PBR: 25 ± 11 μIU·mL(-1)). No significant change (p > 0.05) was observed in total cholesterol. Blood glucose, triglycerides, and insulin all increased significantly in response to both CBR and PBR consumption. The CBR elicited a greater effect on blood glucose; however, the PBR had a strong impact on serum triglycerides and insulin.

Associations between Apolipoprotein E Genotype, Diet, Body Mass Index, and Serum Lipids in Lithuanian Adult Population

BackgroundApolipoprotein E (APOE) polymorphism is associated with lipid levels. Some studies have reported that blood lipid response to diet or obesity varies depending on APOE genotypes. The aim of this study was to assess the effect of APOE genotypes, the intake of saturated fatty acids (SFA), and obesity on serum lipid levels in Lithuanian adult population.Methodology/Principal FindingsA cross-sectional health survey was carried out in five municipalities of Lithuania. The random sample was obtained from lists of 25–64 year-old inhabitants registered at primary health care centres. The data from 996 subjects (416 men and 580 women) were analysed in this study. Two single-nucleotide polymorphisms (rs429358 and rs7412) were assessed using a real-time polymerase chain reaction. 24-hour recall and food frequency questionnaire were used for evaluation of dietary habits. Serum lipids were determined using enzymatic methods.Men and women with the APOE2 genotype had the lowest level of total cholesterol (TC) (p = 0.002 for men, and p = 0.02 for women) and low-density lipoprotein cholesterol (LDL-C) (p<0.001). Multivariate linear regression analysis showed that age, genotype APOE2, SFA intake, and body mass index (BMI) were significant determinants of TC and LDL-C level (with p values ranging from 0.043 to 0.001). Our data did not reveal any statistically significant interactions between APOE genotype and SFA intake or between APOE genotype and BMI regarding TC and LDL-C level (all p>0.05). However, the predictive power of the regression model for LDL-C improved when gene-BMI interaction and gene-BMI interaction plus gene-nutrient interaction were added (p = 0.04 and p = 0.032 for R2 change, respectively).Conclusions/Significance APOE genotypes, SFA intake, and obesity were found to be associated with blood lipid levels in Lithuanian adult population. Analysis of gene-diet and gene-obesity interactions did not confirm that the effects of diet and obesity on TC and LDL-C level significantly depended on APOE genotype.

Abstract P194: Gene-Environment Interactions and Blood Lipid levels: a Twin Study

Genetic variation may affect blood lipid levels by directly determining levels (‘level genes’) and/or by influencing the response to environmental factors (‘variability genes’), i.e. gene-environment interaction. Previous dietary studies assessing variability gene effects have produced inconsistent results, perhaps due to a lack of statistical power, different dietary protocols, and/or differences in the age, sex, habitual diet, baseline lipid values and other genes of the participants. Monozygotic (MZ) twins can enhance our ability to identify variability genes because they are genetically identical and also share the same age, sex and aspects of their early environment. Therefore, all intrapair differences in blood lipid levels are due to environmental factors such as diet and lifestyle, and variation between genotypes in intrapair differences will indicate the existence of variability genes. We investigated the hypothesis that polymorphisms within the genes for apoB, apoE and lipoprotein lipase influence the blood lipid response to environmental factors. The subjects studied were 64 MZ male and female twin pairs aged 18-75 years who had been recruited for a study of coronary heart disease risk factors in twins. Blood samples already taken for analysis of fasting lipid levels were used for DNA extraction. Genotypes were determined for the polymorphisms apoB signal peptide insertion/deletion (I/D), apoB Xba I, apoE, and lipoprotein lipase Pvu II, Hind III and S447X. Mean intrapair differences in lipid levels adjusted for mean twin pair lipid level were calculated for each genotype group. In MZ twins, carriers of the apoB signal peptide D allele had smaller intrapair differences in total cholesterol (p=0.044) but larger intrapair differences in apoAI (p=0.035) than I/I twins, and apoE ε4 carriers had smaller intrapair differences in HDL-cholesterol than E3/3 and E3/2 twins (p=0.024). MZ twins with the Pvu II P-P- genotype had significantly greater intrapair differences in apoB than P-P+ or P+P+ twins. The Xba I, Hind III and S447X polymorphisms did not influence intrapair differences in lipid levels. In conclusion, the apoB signal peptide I/D, apoE and lipoprotein lipase Pvu II polymorphisms may act as variability genes and influence the susceptibility of blood lipid levels to dietary and pharmacological interventions for dyslipidaemia. The approach of using MZ twins to identify variability genes can be applied to other phenotypes, prior to determining the environmental factors that interact with the genes to influence the phenotype.

Effect of low-glycemic load diet on changes in cardiovascular risk factors in poorly controlled diabetic patients.

Background:One dietary strategy aimed at improving both diabetes control and control of cardiovascular risk factors is the use of low glycemic index diets. These diets have been reported to be beneficial in controlling diabetes, and also increase high density lipoprotein cholesterol (HDL-C), lower serum triglyceride, and reduce glycated protein.Aim:Therefore, we aimed to investigate the effect of a low glycemic index-low glycemic load (GL = 67–77) diet on lipids and blood glucose of poorly controlled diabetic patients.Materials and Methods:In an intervention study, 100 poorly controlled diabetic patients (age 52.8 ± 4.5 years) who were taking insulin or on oral medication underwent administration of low GL diet (GL = 67–77; energy = 1800–2200 kcal, total fat = 36%, fat derived from olive oil and nuts 15%, carbohydrate = 41%, protein = 22%) for 10 weeks. Patients were recommended to follow their regular lifestyle. Total cholesterol, low density lipoprotein (LDL), HDL, triglyceride, glycated hemoglobin (HbA1c), weight, and body mass index (BMI) were measured before and 10 weeks after the intervention.Results:Before intervention, initial blood cholesterol and triglyceride concentrations were 205.9 ± 21.6 and 181.5 ± 22.2, respectively, and were reduced to 182.6 ± 18.2 and 161.6 ± 16.7, respectively, after 10 weeks intervention (P < 0.001). LDL reduced and HDL increased significantly. The HbA1c percentage reduced by 12% (from 8.85 ± 0.22% to 7.81 ± 0.27%) (P < 0.001), and also their weight significantly reduced from 74.0 ± 5 kg to 70.7 ± 4.6 kg (P < 0.001).Conclusion:This study demonstrated that low GL diet having lower carbohydrate amount and higher fat content is an appropriate strategy in blood lipid and glucose response control of poorly controlled diabetic patients.

Getting personal: considering variable interindividual responsiveness to dietary lipid-lowering therapies

There is substantial interindividual variation in the response of blood lipids to dietary therapies. The purpose of this review is to highlight recent developments in identifying patient-specific factors that contribute to the significant heterogeneity of responsiveness in lipids to dietary changes and consumption of dietary bioactive compounds. Recent findings suggest that a variety of patient-specific physiological, pathological, environmental, and genetic factors influence the effectiveness of dietary lipid-lowering therapies. Although genetic markers of responsiveness will revolutionize future personalized nutrition therapies, current research priorities should emphasize the identification of readily accessible metabolic biomarkers of responsiveness in patient subgroups.

Acute glycemic and blood lipid response to the ingestion of a candy bar-like protein supplement compared to its candy bar counterpart

Background To meet the growing demand and market for protein supplements, sports nutrition companies and manufacturers have developed protein supplements in several forms, such as RTDs, bars, and powders. Recently, candy bar-like protein supplements have been developed using sugar alcohols instead of sugar to lessen the glycemic response. However, these candy bar-like substitutes usually have a high concentration of total fat, saturated fat, and cholesterol. It is the purpose of this study therefore to determine the acute glycemic and blood lipid response to ingesting a candy bar-like protein supplement compared to its candy bar counterpart.

Advances in Exercise, Fitness, and Performance Genomics

An annual review publication of the most significant articles in exercise, fitness, and performance genomics begins with this article, which covers 2 yr, 2008 and 2009. The review emphasizes the strongest articles as defined by sample size, quality of phenotype measurements, quality of the exercise program or physical activity exposure, study design, adjustment for multiple testing, quality of genotyping, and other related study characteristics. With this avowed focus on the highest quality articles, only a small number of published articles are reviewed. Among the most significant findings reported here are a brief overview of the first genome-wide association study of the genetic differences between exercisers and nonexercisers. In addition, the latest results on the actinin alpha 3 (ACTN3) R577X nonsense polymorphism are reviewed, emphasizing that no definitive conclusion can be reached at this time. Recent studies that have dealt with mitochondrial DNA haplogroups and endurance performance are described. Published reports indicating that physical activity may attenuate the effect of the fat mass and obesity associated (FTO) gene risk allele on body mass index are reviewed. Articles that have tested the contributions of specific genes to the response of glucose and insulin metabolism traits to regular exercise or physical activity level are considered and found to be generally inconclusive at this stage. Studies examining ethnic differences in the response of blood lipids and lipoproteins to exercise training cannot unequivocally relate these to apolipoprotein E (APOE) genotypes. Hemodynamic changes with exercise training were reported to be associated to sequence variation in kinesin heavy chain (KIF5B), but no replication study is available as of yet. We conclude from this first installment that exercise scientists need to prioritize high-quality research designs and that replication studies with large sample sizes are urgently needed.

The usefulness of a Mediterranean-based diet in individuals with type 2 diabetes

This article reviews current data available on the Mediterranean diet related to its use in a diabetic population. Based on many published reports, it is apparent that the Mediterranean diet may be used in dietary interventions for the treatment of overweight and obesity, conditions associated with the development of type 2 diabetes. In addition, obesity in type 2 diabetic persons is associated with other cardiovascular disease risk factors. The Mediterranean diet has been found to be inversely related to the metabolic syndrome, often a feature of diabetic individuals. Perhaps the most critical information placing the Mediterranean diet in a favorable position is the positive response of insulin, blood glucose, blood lipids, and other metabolic factors predicting cardiovascular disease risk and outcomes. This diet is a viable treatment option; advisors should stress not only adherence to a fairly traditional Mediterranean eating plan but also a lifestyle that includes sufficient physical activity.

Longitudinal impact of physical activity on lipid profiles in middle-aged adults: the Atherosclerosis Risk in Communities Study

Evidence exists that increased levels of physical activity decrease the population burden of cardiovascular disease (CVD). Although risk factors for CVD, including plasma lipids and lipoproteins, have been associated with physical activity, studies including a sizeable number of minority participants are lacking. Our purpose was to interrogate the longitudinal effect of physical activity on plasma lipids and lipoproteins in the African American and white participants of the Atherosclerosis Risk in Communities (ARIC) Study. Nine years of follow-up data on 8,764 individuals aged 45-64 years at baseline were used in linear mixed-effects models to estimate the association between increases in baseline physical activity on mean change in HDL, LDL, total cholesterol, and triglyceride levels. Increases in the level of activity were associated with increases in HDL in all strata and decreases in triglycerides among white participants. Physical activity was associated with LDL in all women, while the association with total cholesterol was limited to African American women. This study is one of the few to investigate the effect of physical activity on lipids and lipoproteins in a race- and sex-specific manner. Overall our results highlight the importance of physical activity on plasma lipid profiles and provide evidence for novel differential associations.

Nutrient gene interactions in lipid metabolism

To summarize recent findings relating to the impact of dietary fat composition on whole body lipid metabolism, and common gene variants on the blood lipid response to dietary fat change. In recent years a more comprehensive understanding of the impact of polyunsaturated fat (PUFA) intake on the regulation of transcription factors involved in lipogenesis and fatty acid and lipoprotein metabolism has emerged. The evidence is suggestive of a greater potency of the long chain n-3 PUFA, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and in particular their oxidative products, relative to n-6 PUFA. In the area of nutrigenetics a number of common gene variants have been identified which may be important determinants of the blood lipid response to altered dietary fat composition. However, confirmation of associations in independent cohorts, and an understanding of the size effect of individual or combinations of genotypes, is often lacking. Although in the future, genotyping holds the potential as a public health tool to target and personalize dietary advice, nutrigenetics is a relatively new science, and further research is needed to address the existing inconsistencies and knowledge gaps.

Acute metabolic responses to butter, margarine, and a monoglyceride gel-structured spread

Cardiovascular and metabolic health concerns have led to interest in development of saturated- and trans fat-free margarines, spreads, and other foods. We have recently characterized a novel monoglyceride gel (MAG GEL) that can structure liquid oil into a semi-plastic solid consistency in the absence of saturated and trans fats. Consumption of this MAG GEL resulted in tempered postprandial metabolic responses compared to those resulting from consumption of a compositionally equivalent but unstructured oil suspension, suggesting a structure-dependent metabolic response. The current study was designed to test the hypothesis that postprandial blood lipid and metabolite responses to MAG GEL would be tempered compared to the responses after ingestion of butter and tub-margarine of equal total fat content. Indeed, blood triglyceride response was tempered in MAG GEL compared to butter, margarine, and unstructured oil trials, all of which produced similar triglyceride responses. The blood free fatty acid, glucose, and insulin responses were not different in MAG GEL compared to butter or margarine trials; and interestingly, there were no differences between butter and margarine trials for any of the metabolic response variables. The MAG GEL is a useful structure for many applications, and produces salubrious postprandial metabolic effects compared to other spreadable fats.

The influence of cinnamon supplementation on blood glucose and lipid responses in rats

Studies have shown that cinnamon supplementation improves fasting blood glucose levels and lipid profiles in individuals with type 2 diabetes. However, these findings have not been universally reported and limited data are available on the effects of cinnamon on non‐diabetics. The aim of this study was to determine the influence of cinnamon on plasma glucose, cholesterol and triglycerides. Sixteen male weanling Sprague‐Dawley rats were equally divided into two groups and fed either a high‐fat (21g/100g) control diet or a high‐fat diet supplemented with commercial cinnamon (1g/100g) for 30 days. Food intake (420.2 ± 36.0 vs. 457.0 ± 45.1 g), weight gain (189.2 ± 20.9 vs. 189.0 ± 15.1 g), fat pad weights (2.938 ± 0.646 vs. 2.811 ± 0.488 g) and glucose levels (163.0 ± 30.7 vs. 169.8 ± 41.7 mg/dl) were similar (p&gt;0.05) between rats fed cinnamon and the control diet, respectively. Total cholesterol tended to be higher (p=.054) for rats fed cinnamon (93.0 ± 11.6 mg/dl) versus the control diet (80.7 ± 18.8 mg/dl). No differences (p&gt;0.05) in triglyceride (52.8 ± 29.7 vs. 51.3 ± 10.3 mg/dl), HDL‐cholesterol (59.3 ± 8.3 vs. 56.5 ± 5.8 mg/dl) or non‐HDL‐cholesterol (33.8 ± 4.7 vs. 30.13 ± 11.8 mg/dl) levels were detected between the cinnamon‐fed versus control‐fed rats. Cinnamon failed to reduce glucose levels or improve lipids. More research on the proposed health benefits of cinnamon is warranted before generalized claims should be made.

Physical Activity and Fitness in African Americans: Implications for Cardiovascular Health

The prevalence of cardiovascular disease (CVD), obesity, diabetes mellitus, hypertension, and physical inactivity is significantly higher in African Americans. The higher prevalence of these important risk factors is thought to be largely responsible for the higher CVD mortality rate in blacks. Limited evidence suggests that the aerobic power of African Americans may be inherently lower than that of whites. This apparent deficiency may be explained, in part, by differences in muscle oxidative capacity but is poorly understood. Studies have shown a lower prevalence of overweight/obesity, the metabolic syndrome, and insulin resistance with higher levels of physical activity/fitness. Training studies have shown that increasing physical activity and/or fitness positively affects metabolic risk factors, body composition, and insulin sensitivity. The few studies of African Americans suggest that they respond to exercise training in a manner similar to whites. Controlling blood pressure of hypertensive blacks at levels comparable with that of whites could result in more than 7000 fewer deaths from CVD. Physical fitness has been shown to be negatively associated with blood pressure in African Americans, but results from interventional studies have been equivocal. Some evidence suggests that increased physical activity and/or fitness may reduce the blood pressure response to submaximal exercise and other stressors in African Americans. Blacks have higher levels of high-density lipoprotein cholesterol (HDL-C) and lower levels of total cholesterol, triglycerides, and small dense low-density lipoprotein particles. Studies suggest that the blood lipid response to exercise training is similar between African Americans and whites. There may be an intensity threshold of 75% of age-predicted maximal heart rate to elicit significant changes in HDL-C. More research is needed to explore the association between physical activity/fitness and CVD risk factors in this population.

Effect of food preparation on the structure and metabolic responses to a monostearin–oil–water gel-based spread

Abstract Widespread recognition of the negative health effects of trans and saturated fats has prompted research to develop alternative structures that can structure liquid oils into semi-solid plastic pastes for food applications. We have recently developed and described the physical chemical properties of a unique a monostearin–oil–water gel (MAG) that achieves this goal. Furthermore, ingestion of this MAG in the form of a margarine-like spread resulted in beneficial suppression of blood lipid and insulin responses in humans compared to compositionally-equivalent controls lacking the MAG structure. However, the integrity of this novel structure and its salubrious metabolic effects have not been previously evaluated under food processing conditions. The purpose of the current study was to evaluate the integrity of the MAG when applied to toasted bread and when mixed with a warm pasta meal, and to evaluate the metabolic effects over 6 h following ingestion of both types of meals with MAG compared to compositionally-equivalent unstructured oil preparations. MAG structure was maintained in the toast study, but the pasta meal destroyed the MAG structure. Triglyceride, free fatty acid, and insulin responses were suppressed in the MAG trial compared to the unstructured oil trial of the toast study, whereas there was no difference in the responses of these variables between the two trials in the pasta study. The results demonstrate for the first time that the metabolic effects of MAG depend on maintenance of the MAG structural integrity throughout the food processing procedures leading up to ingestion. Thus, this study demonstrates the utility of MAG as a trans- and saturated fat-free vehicle to structure and deliver liquid oil as a semi-solid plastic paste, and establishes processing limits to the integrity of the additional beneficial metabolic effects of this novel structure.

Controlled Release of Food Lipids Using Monoglyceride Gel Phases Regulates Lipid and Insulin Metabolism in Humans

We describe a solid vegetable oil–water gel structure which is stabilized through the use of low concentrations of monoglycerides, containing no added trans fats or saturated fats. The resulting structure consists of oil droplets encapsulated in self-assembled crystalline monoglyceride multilayers, surrounded by a continuous water phase. Acute ingestion human feeding trials indicated that the serum triglyceride loading was significantly lower after ingestion of the structured gel rather than a simple oil–water mixture, resulting in an attenuated increase in serum insulin. This indicates the effectiveness of encapsulation in modulating blood lipid and insulin response in humans, and suggests a strategy that can be employed for the controlled release of food macronutrients.