A Web-Based Health Application to Translate Nutrition Therapy for Cardiovascular Risk Reduction in Primary Care (PortfolioDiet.app): Quality Improvement and Usability Testing Study.

BACKGROUND: The Portfolio Diet, or Dietary Portfolio, is a therapeutic dietary pattern that combines cholesterol-lowering foods to manage dyslipidemia for the prevention of cardiovascular disease. To translate the Portfolio Diet for primary care, we developed the PortfolioDiet.app as a patient and physician educational and engagement tool for PCs and smartphones. The PortfolioDiet.app is currently being used as an add-on therapy to the standard of care (usual care) for the prevention of cardiovascular disease in primary care. To enhance the adoption of this tool, it is important to ensure that the PortfolioDiet.app meets the needs of its target end users. OBJECTIVE: The main objective of this project is to undertake user testing to inform modifications to the PortfolioDiet.app as part of ongoing engagement in quality improvement (QI). METHODS: We undertook a 2-phase QI project from February 2021 to September 2021. We recruited users by convenience sampling. Users included patients, family physicians, and dietitians, as well as nutrition and medical students. For both phases, users were asked to use the PortfolioDiet.app daily for 7 days. In phase 1, a mixed-form questionnaire was administered to evaluate the users' perceived acceptability, knowledge acquisition, and engagement with the PortfolioDiet.app. The questionnaire collected both quantitative and qualitative data, including 2 open-ended questions. The responses were used to inform modifications to the PortfolioDiet.app. In phase 2, the System Usability Scale was used to assess the usability of the updated PortfolioDiet.app, with a score higher than 70 being considered acceptable. RESULTS: A total of 30 and 19 users were recruited for phase 1 and phase 2, respectively. In phase 1, the PortfolioDiet.app increased users' perceived knowledge of the Portfolio Diet and influenced their perceived food choices. Limitations identified by users included challenges navigating to resources and profile settings, limited information on plant sterols, inaccuracies in points, timed-logout frustration, request for step-by-step pop-up windows, and request for a mobile app version; when looking at positive feedback, the recipe section was the most commonly praised feature. Between the project phases, 6 modifications were made to the PortfolioDiet.app to incorporate and address user feedback. At phase 2, the average System Usability Scale score was 85.39 (SD 11.47), with 100 being the best possible. CONCLUSIONS: By undertaking user testing of the PortfolioDiet.app, its limitations and strengths were able to be identified, informing modifications to the application, which resulted in a clinical tool that better meets users' needs. The PortfolioDiet.app educates users on the Portfolio Diet and is considered acceptable by users. Although further refinements to the PortfolioDiet.app will continue to be made before its evaluation in a clinical trial, the result of this QI project is an improved clinical tool.

Almond Bioaccessibility in a Randomized Crossover Trial: Is a Calorie a Calorie?

OBJECTIVE: To investigate the energy and macronutrient bioaccessibility of almonds in individuals with hyperlipidemia. METHODS: In a previously reported randomized crossover trial, men and postmenopausal women with hyperlipidemia incorporated 3 isoenergetic supplements into a National Cholesterol Education Program Step 2 diet for 1 month each between September 20, 2000, and June 27, 2001. Supplements provided consisted of full-dose almonds (73±5 g/d), half-dose almonds (38±3 g/d) plus half-dose muffins, and full-dose muffins (control). Energy and macronutrients, including individual fatty acids, were measured in the dietary supplements and fecal samples using gas chromatography and Association of Official Analytical Chemists methods. Serum was measured for lipids and fatty acids. Bioaccessibility of energy and macronutrients from almond consumption was assessed from dietary intake (7-day food records) and fecal output. RESULTS: Almond-related energy bioaccessibility was 78.5%±3.1%, with an average energy loss of 21.2%±3.1% (40.6 kcal/d in the full-dose almond phase). Bioaccessibility of energy and fat from the diet as a whole was significantly less with almond consumption (in both half- and full-dose phases) compared with the control. Bioaccessibility of fat was significantly different between treatment phases (P<.001) and on average lower by 5.1% and 6.3% in the half- and full-dose almond phases, respectively, compared with the control phase. Energy bioaccessibility was significantly different between the treatment phases (P=.02), decreasing by approximately 2% with the inclusion of the full dose of almonds compared with the control. CONCLUSION: Energy content of almonds may not be as bioaccessible in individuals with hyperlipidemia as predicted by Atwater factors, as suggested by the increased fat excretion with almond intake compared with the control. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00507520.

Supplemental Vitamins and Minerals for Cardiovascular Disease Prevention and Treatment: JACC Focus Seminar.

This is an update of the previous 2018 systematic review and meta-analysis of vitamin and mineral supplementation on cardiovascular disease outcomes and all-cause mortality. New randomized controlled trials and meta-analyses were identified by searching the Cochrane library, Medline, and Embase, and data were analyzed using random effects models and classified by the Grading of Recommendations Assessment Development and Evaluation approach. This updated review shows similar findings to the previous report for preventive benefits from both folic acid and B vitamins for stroke and has been graded with moderate quality. No effect was seen for the commonly used multivitamins, vitamin D, calcium, and vitamin C, and an increased risk was seen with niacin (with statin) for all-cause mortality. Conclusive evidence for the benefit of supplements across different dietary backgrounds, when the nutrient is sufficient, has not been demonstrated.

Selenium, antioxidants, cardiovascular disease, and all-cause mortality: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Antioxidants have been promoted for cardiovascular disease (CVD) risk reduction and for the prevention of cancer. Our preliminary analysis suggested that only when selenium was present were antioxidant mixtures associated with reduced all-cause mortality. OBJECTIVE: We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to determine the effect of selenium supplementation alone and of antioxidant mixtures with or without selenium on the risk of CVD, cancer, and mortality. METHODS: We identified studies using the Cochrane Library, Medline, and Embase for potential CVD outcomes, cancer, and all-cause mortality following selenium supplementation alone or after antioxidant supplement mixtures with and without selenium up to June 5, 2020. RCTs of ≥24 wk were included and data were analyzed using random-effects models and classified by the Grading of Recommendations, Assessment, Development, and Evaluation approach. RESULTS: The meta-analysis identified 9423 studies, of which 43 were used in the final analysis. Overall, no association of selenium alone or antioxidants was seen with CVD and all-cause mortality. However, a decreased risk with antioxidant mixtures was seen for CVD mortality when selenium was part of the mix (RR: 0.77; 95% CI: 0.62, 0.97; P = 0.02), with no association when selenium was absent. Similarly, when selenium was part of the antioxidant mixture, a decreased risk was seen for all-cause mortality (RR: 0.90; 95% CI: 0.82, 0.98; P = 0.02) as opposed to an increased risk when selenium was absent (RR: 1.09; 95% CI: 1.04, 1.13; P = 0.0002). CONCLUSION: The addition of selenium should be considered for supplements containing antioxidant mixtures if they are to be associated with CVD and all-cause mortality risk reduction. This trial was registered at https://www.crd.york.ac.uk/PROSPERO/ as CRD42019138268.

Dietary Fibre Consensus from the International Carbohydrate Quality Consortium (ICQC).

Dietary fibre is a generic term describing non-absorbed plant carbohydrates and small amounts of associated non-carbohydrate components. The main contributors of fibre to the diet are the cell walls of plant tissues, which are supramolecular polymer networks containing variable proportions of cellulose, hemicelluloses, pectic substances, and non-carbohydrate components, such as lignin. Other contributors of fibre are the intracellular storage oligosaccharides, such as fructans. A distinction needs to be made between intrinsic sources of dietary fibre and purified forms of fibre, given that the three-dimensional matrix of the plant cell wall confers benefits beyond fibre isolates. Movement through the digestive tract modifies the cell wall structure and may affect the interactions with the colonic microbes (e.g., small intestinally non-absorbed carbohydrates are broken down by bacteria to short-chain fatty acids, absorbed by colonocytes). These aspects, combined with the fibre associated components (e.g., micronutrients, polyphenols, phytosterols, and phytoestrogens), may contribute to the health outcomes seen with the consumption of dietary fibre. Therefore, where possible, processing should minimise the degradation of the plant cell wall structures to preserve some of its benefits. Food labelling should include dietary fibre values and distinguish between intrinsic and added fibre. Labelling may also help achieve the recommended intake of 14 g/1000 kcal/day.

Cumulative Meta-Analysis of the Soy Effect Over Time.

Background Soy protein foods have attracted attention as useful plant protein foods with mild cholesterol-lowering effects that are suitable for inclusion in therapeutic diets. But on the basis of the lack of consistency in significant cholesterol reduction by soy in 46 randomized controlled trials, the US Food and Drug Administration (FDA) is reassessing whether the 1999 heart health claim for soy protein should be revoked. Methods and Results We have, therefore, performed a cumulative meta-analysis on the 46 soy trials identified by the FDA to determine if at any time, since the 1999 FDA final rule that established the soy heart health claim, the soy effect on serum cholesterol lost significance. The cumulative meta-analysis for both total cholesterol and low-density lipoprotein cholesterol demonstrated preservation of the small, but significant, reductions seen both before and during the subsequent 14 years since the health claim was originally approved. For low-density lipoprotein cholesterol, the mean reduction in 1999 was -6.3 mg/dL (95% CI, -8.7 to -3.9 mg/dL; P=0.00001) and remained in the range of -4.2 to -6.7 mg/dL ( P=0.0006 to P=0.0002, respectively) in the years after 1999. At no time point did the total cholesterol or low-density lipoprotein cholesterol reductions lose significance or were the differences at individual time points in the cumulative meta-analysis significantly different from those seen in 1999 when the health claim was approved. Conclusions A cumulative meta-analysis of the data selected by the FDA indicates continued significance of total cholesterol and low-density lipoprotein cholesterol reduction after soy consumption and supports the rationale behind the original soy FDA heart health claim.

Supplemental Vitamins and Minerals for CVD Prevention and Treatment.

The authors identified individual randomized controlled trials from previous meta-analyses and additional searches, and then performed meta-analyses on cardiovascular disease outcomes and all-cause mortality. The authors assessed publications from 2012, both before and including the U.S. Preventive Service Task Force review. Their systematic reviews and meta-analyses showed generally moderate- or low-quality evidence for preventive benefits (folic acid for total cardiovascular disease, folic acid and B-vitamins for stroke), no effect (multivitamins, vitamins C, D, ß-carotene, calcium, and selenium), or increased risk (antioxidant mixtures and niacin [with a statin] for all-cause mortality). Conclusive evidence for the benefit of any supplement across all dietary backgrounds (including deficiency and sufficiency) was not demonstrated; therefore, any benefits seen must be balanced against possible risks.

Low glycemic index diet, exercise and vitamin D to reduce breast cancer recurrence (DEDiCa): design of a clinical trial.

BACKGROUND: Mechanisms influencing breast cancer (BC) development and recurrence include hyperglycemia, hyperinsulinemia, high insulin-like growth factor-1, high circulating estrogen, inflammation and impaired cellular differentiation/apoptosis. A lifestyle program that targets all the above mechanisms may be warranted. Low glycemic index (GI) foods produce lower post-prandial glucose and insulin responses and have been associated with lower BC risk. Moderate physical activity post-diagnosis reduces BC recurrence and mortality, partly explained by reduced insulin and estrogen levels. Vitamin D increases cell differentiation/apoptosis and high serum vitamin D levels improve BC survival. Yet no trial has evaluated the combined effect of a low GI diet, moderate physical activity and vitamin D supplementation on BC recurrence in the context of a Mediterranean lifestyle setting. METHODS: Women (30-74 yr) who had undergone surgery for primary histologically confirmed BC (stages I-III) within the previous 12 months, in cancer centres in Italy, will be randomized to follow, for a maximum of 33 months, either a high intensity treatment (HIT) composed of low GI diet + exercise + vitamin D (60 ng/mL serum concentration) or a lower intensity treatment (LITE) with general advice to follow a healthy diet and exercise pattern + vitamin D to avoid insufficiency. Both interventions are on a background of a Mediterranean diet. Considering a 20% recurrence rate within 3 years for BC cases and a predicted rate of 10% in the HIT group, with power of 80% and two-sided alpha of 0.05, the subject number required will be 506 (n = 253 in each arm). Clinic visits will be scheduled every 3 months. Dietary and exercise counselling and vitamin D supplements will be given at each clinic visit when blood samples, anthropometric measures and 7-day food records will be collected. DISCUSSION: DEDiCa study aims to reduce BC recurrence in women with BC using a lifestyle approach with additional vitamin D and to investigate possible cardio-metabolic benefits as well as epigenetic modifications according to lifestyle changes. Given the supporting evidence and safety of the components of our intervention we believe it is feasible and urgent to test it in cancer patients. TRIAL REGISTRATION: May 11, 2016; NCT02786875 . EUDRACT NUMBER: 2015-005147-14.

Effect of almond consumption on the serum fatty acid profile: a dose-response study.

Consumption of almonds has been shown to be associated with a decreased risk of CHD, which may be related to their fatty acid (FA) composition. However, the effect of almond consumption on the serum FA composition is not known. Therefore, in the present study, we investigated whether almond consumption would alter the serum FA profile and risk of CHD, as calculated using Framingham's 10-year risk score, in a dose-dependent manner in hyperlipidaemic individuals when compared with a higher-carbohydrate control group using dietary interventions incorporating almonds. A total of twenty-seven hyperlipidaemic individuals consumed three isoenergetic (mean 1770 kJ/d) supplements during three 1-month dietary phases: (1) full-dose almonds (50-100 g/d); (2) half-dose almonds with half-dose muffins; (3) full-dose muffins. Fasting blood samples were obtained at weeks 0 and 4 for the determination of FA concentrations. Almond intake (g/d) was found to be inversely associated with the estimated Framingham 10-year CHD risk score (P= 0·026). In both the half-dose and full-dose almond groups, the proportions of oleic acid (OA) and MUFA in the TAG fraction (half-almond: OA P= 0·003; MUFA P= 0·004; full-almond: OA P< 0·001; MUFA P< 0·001) and in the NEFA fraction (half-almond: OA P= 0·01; MUFA P= 0·04; full-almond: OA P= 0·12; MUFA P= 0·06) increased. The estimated Framingham 10-year CHD risk score was inversely associated with the percentage change of OA (P= 0·011) and MUFA (P= 0·016) content in the TAG fraction. The proportions of MUFA in the TAG and NEFA fractions were positively associated with changes in HDL-cholesterol concentrations. Similarly, the estimated Framingham 10-year CHD risk score was inversely associated with the percentage change of OA (P= 0·069) and MUFA content in the NEFA fraction (P= 0·009). In conclusion, the results of the present study indicate that almond consumption increases OA and MUFA content in serum TAG and NEFA fractions, which are inversely associated with CHD lipid risk factors and overall estimated 10-year CHD risk.

Effect of tree nuts on glycemic control in diabetes: a systematic review and meta-analysis of randomized controlled dietary trials.

BACKGROUND: Tree nut consumption has been associated with reduced diabetes risk, however, results from randomized trials on glycemic control have been inconsistent. OBJECTIVE: To provide better evidence for diabetes guidelines development, we conducted a systematic review and meta-analysis of randomized controlled trials to assess the effects of tree nuts on markers of glycemic control in individuals with diabetes. DATA SOURCES: MEDLINE, EMBASE, CINAHL, and Cochrane databases through 6 April 2014. STUDY SELECTION: Randomized controlled trials ≥3 weeks conducted in individuals with diabetes that compare the effect of diets emphasizing tree nuts to isocaloric diets without tree nuts on HbA1c, fasting glucose, fasting insulin, and HOMA-IR. DATA EXTRACTION AND SYNTHESIS: Two independent reviewer's extracted relevant data and assessed study quality and risk of bias. Data were pooled by the generic inverse variance method and expressed as mean differences (MD) with 95% CI's. Heterogeneity was assessed (Cochran Q-statistic) and quantified (I2). RESULTS: Twelve trials (n = 450) were included. Diets emphasizing tree nuts at a median dose of 56 g/d significantly lowered HbA1c (MD = -0.07% [95% CI:-0.10, -0.03%]; P = 0.0003) and fasting glucose (MD = -0.15 mmol/L [95% CI: -0.27, -0.02 mmol/L]; P = 0.03) compared with control diets. No significant treatment effects were observed for fasting insulin and HOMA-IR, however the direction of effect favoured tree nuts. LIMITATIONS: Majority of trials were of short duration and poor quality. CONCLUSIONS: Pooled analyses show that tree nuts improve glycemic control in individuals with type 2 diabetes, supporting their inclusion in a healthy diet. Owing to the uncertainties in our analyses there is a need for longer, higher quality trials with a focus on using nuts to displace high-glycemic index carbohydrates. TRIAL REGISTRATION: ClinicalTrials.gov NCT01630980.

Effect of lowering the glycemic load with canola oil on glycemic control and cardiovascular risk factors: a randomized controlled trial.

OBJECTIVE: Despite their independent cardiovascular disease (CVD) advantages, effects of α-linolenic acid (ALA), monounsaturated fatty acid (MUFA), and low-glycemic-load (GL) diets have not been assessed in combination. We therefore determined the combined effect of ALA, MUFA, and low GL on glycemic control and CVD risk factors in type 2 diabetes. RESEARCH DESIGN AND METHODS: The study was a parallel design, randomized trial wherein each 3-month treatment was conducted in a Canadian academic center between March 2011 and September 2012 and involved 141 participants with type 2 diabetes (HbA1c 6.5%-8.5% [48-69 mmol/mol]) treated with oral antihyperglycemic agents. Participants were provided with dietary advice on either a low-GL diet with ALA and MUFA given as a canola oil-enriched bread supplement (31 g canola oil per 2,000 kcal) (test) or a whole-grain diet with a whole-wheat bread supplement (control). The primary outcome was HbA1c change. Secondary outcomes included calculated Framingham CVD risk score and reactive hyperemia index (RHI) ratio. RESULTS: Seventy-nine percent of the test group and 90% of the control group completed the trial. The test diet reduction in HbA1c units of -0.47% (-5.15 mmol/mol) (95% CI -0.54% to -0.40% [-5.92 to -4.38 mmol/mol]) was greater than that for the control diet (-0.31% [-3.44 mmol/mol] [95% CI -0.38% to -0.25% (-4.17 to -2.71 mmol/mol)], P = 0.002), with the greatest benefit observed in those with higher systolic blood pressure (SBP). Greater reductions were seen in CVD risk score for the test diet, whereas the RHI ratio increased for the control diet. CONCLUSIONS: A canola oil-enriched low-GL diet improved glycemic control in type 2 diabetes, particularly in participants with raised SBP, whereas whole grains improved vascular reactivity.

Digestive and physiologic effects of a wheat bran extract, arabino-xylan-oligosaccharide, in breakfast cereal.

OBJECTIVE: We assessed whether a wheat bran extract containing arabino-xylan-oligosaccharide (AXOS) elicited a prebiotic effect and influenced other physiologic parameters when consumed in ready-to-eat cereal at two dose levels. METHODS: This double-blind, randomized, controlled, crossover trial evaluated the effects of consuming AXOS at 0 (control), 2.2, or 4.8 g/d as part of ready-to-eat cereal for 3 wk in 55 healthy men and women. Fecal microbial levels, postprandial serum ferulic acid concentrations, and other physiologic parameters were assessed at the beginning and end of each condition. RESULTS: The median bifidobacteria content of stool samples (log10/grams of dry weight [DW]) was found to be higher in the subjects consuming the 4.8-g/d dose (10.03) than in those consuming 2.2 g/d (9.93) and control (9.84, P < 0.001). No significant changes in the populations of other fecal microbes were observed, indicating a selective increase in fecal bifidobacteria. Postprandial ferulic acid was measured at 120 min at the start and end of each 3-wk treatment period in subjects at least 50 y old (n = 37) and increased in a dose-dependent manner (end-of-treatment values 0.007, 0.050, and 0.069 µg/mL for the control, AXOS 2.2 g/d, and AXOS 4.8 g/d conditions, respectively, P for trend < 0.001). CONCLUSION: These results indicate that AXOS has prebiotic properties, selectively increasing fecal bifidobacteria, and increases postprandial ferulic acid concentrations in a dose-dependent manner in healthy men and women.

The effects of fructose intake on serum uric acid vary among controlled dietary trials.

Hyperuricemia is linked to gout and features of metabolic syndrome. There is concern that dietary fructose may increase uric acid concentrations. To assess the effects of fructose on serum uric acid concentrations in people with and without diabetes, we conducted a systematic review and meta-analysis of controlled feeding trials. We searched MEDLINE, EMBASE, and the Cochrane Library for relevant trials (through August 19, 2011). Analyses included all controlled feeding trials ≥ 7 d investigating the effect of fructose feeding on uric acid under isocaloric conditions, where fructose was isocalorically exchanged with other carbohydrate, or hypercaloric conditions, and where a control diet was supplemented with excess energy from fructose. Data were aggregated by the generic inverse variance method using random effects models and expressed as mean difference (MD) with 95% CI. Heterogeneity was assessed by the Q statistic and quantified by I(2). A total of 21 trials in 425 participants met the eligibility criteria. Isocaloric exchange of fructose for other carbohydrate did not affect serum uric acid in diabetic and nondiabetic participants [MD = 0.56 µmol/L (95% CI: -6.62, 7.74)], with no evidence of inter-study heterogeneity. Hypercaloric supplementation of control diets with fructose (+35% excess energy) at extreme doses (213-219 g/d) significantly increased serum uric acid compared with the control diets alone in nondiabetic participants [MD = 31.0 mmol/L (95% CI: 15.4, 46.5)] with no evidence of heterogeneity. Confounding from excess energy cannot be ruled out in the hypercaloric trials. These analyses do not support a uric acid-increasing effect of isocaloric fructose intake in nondiabetic and diabetic participants. Hypercaloric fructose intake may, however, increase uric acid concentrations. The effect of the interaction of energy and fructose remains unclear. Larger, well-designed trials of fructose feeding at "real world" doses are needed.

Health effects of mixed fruit and vegetable concentrates: a systematic review of the clinical interventions.

Diets rich in fruits and vegetables (FV) have been associated with a reduced risk of chronic disease, including cardiovascular disease. Unfortunately, public health campaigns to increase FV intake have had limited success. A number of mixed concentrated FV products have been studied, which may help certain individuals improve nutrient status. However, the possible health benefits of FV supplements have not been systematically reviewed. We, therefore, undertook a systematic search of MEDLINE and EMBASE to identify clinical interventions that examined the effect of commercially available concentrated mixed FV supplements on cardiovascular disease risk factors. Twenty-two reports, which used commercially available products, were identified. None of the studies reported any serious adverse effects. Overall, daily consumption of FV supplements significantly increased serum concentrations of the major antioxidant provitamins and vitamins found in plant foods (ß-carotene, vitamins C and E) and folate. Functional changes, such as reduced serum homocysteine and markers of protein, lipid, and DNA oxidation, were also reported; in addition, the health advantages on markers of inflammation, immunity, and endothelial function are promising. Limitations of the available studies were related to the diversity of studies conducted with respect to design and study population and the variability in the measured outcomes and assays utilized. While mixed FV supplements may serve as an efficacious complement for individuals who have difficulty achieving their daily FV intake requirement, further research on additional retail preparations is warranted. Key teaching points: Mixed fruit and vegetable supplements produced from plant foods may serve as an efficacious complement to the habitual diet in individuals who have suboptimal intake or variety of nutrient-dense fruits and vegetables. Current research indicates that fruit and vegetable concentrates significantly increase serum levels of antioxidant provitamins and vitamins (ß-carotene, vitamins C and E) and folate and reduce homocysteine and markers of oxidative stress. Mechanistic studies and larger, randomized, placebo-controlled double-blind trials in both healthy and high-risk populations are necessary to better understand the health effects of these supplements.

The effect of physiological concentrations of sex hormones, insulin, and glucagon on growth of breast and prostate cells supplemented with unmodified human serum.

The majority of cell culture studies have assessed the effect of hormones on cancer cell growth using media supplemented with charcoal-treated fetal bovine serum (CTS). We aimed to determine whether using a system more reflective of the human condition by changing the charcoal-treated serum to an untreated pooled human serum (PHS) resulted in the same hormone responses in breast and prostate cell lines. MCF-7 breast cancer, MCF-10A non-transformed breast, and LNCaP prostate cancer cell lines supplemented with PHS were treated with high and low physiological concentrations of six hormones (17ß-estradiol, dehydroepiandosterone (DHEA), dihydrotestosterone (DHT), testosterone, insulin, and glucagon). Cell growth was measured after 72 h of incubation. All hormones stimulated growth of MCF-7 cells (p < 0.05). MCF-10A cell growth was inhibited by DHEA, DHT, and testosterone (p < 0.05), unaffected by 17ß-estradiol and glucagon, and stimulated by insulin (p < 0.05). LNCaP cell growth was stimulated by the highest concentration of DHEA and DHT (p < 0.05) and inhibited by the highest concentration of 17ß-estradiol (p < 0.05), while insulin and testosterone, had no effect. Overall, PHS lowered the magnitude of the effect of hormones on cell growth in comparison to CTS. Due to the presence of all serum constituents, our model represents a more appropriate physiological environment for determining the effect of hormones on cancer cell growth. Further studies are required to determine the mechanisms by which added hormones interact with the constituents of untreated human serum.

Supplemental barley protein and casein similarly affect serum lipids in hypercholesterolemic women and men.

High-protein diets have been advocated for weight loss and the treatment of diabetes. Yet animal protein sources are often high in saturated fat and cholesterol. Vegetable protein sources, by contrast, are low in saturated fat and without associated cholesterol. We have therefore assessed the effect on serum lipids of raising the protein intake by 5% using a cereal protein, barley protein, as part of a standard therapeutic diet. Twenty-three hypercholesterolemic men and postmenopausal women completed a randomized crossover study comparing a bread enriched with either barley protein or calcium caseinate [30 g protein, 8374 kJ (2000 kcal)] taken separately as two 1-mo treatment phases with a minimum 2-wk washout. Body weight and diet history were collected weekly during each treatment. Fasting blood samples were obtained at wk 0, 2, and 4. Palatability, satiety, and compliance were similar for both the barley protein- and casein-enriched breads, with no differences between the treatments in effects on serum LDL cholesterol or C-reactive protein, measures of oxidative stress, or blood pressure. Nevertheless, because no adverse effects were observed on cardiovascular risk factors, barley protein remains an additional option for raising the protein content of the diet.

Session 4: CVD, diabetes and cancer: A dietary portfolio for management and prevention of heart disease.

CHD is the leading cause of worldwide mortality. The prevalence of heart disease has been linked to the adoption of a sedentary lifestyle and the increased dietary dependence on saturated fats from animal sources and the intake of refined foods. Elevated blood cholesterol level is one of the major risk factors for CHD. While cholesterol-lowering drug therapy (statins) has been effective in reducing the risk of heart disease, there are those individuals who are unwilling or because of muscle pains or raised levels of liver or muscle enzymes are unable to take cholesterol-lowering medication. Fortunately, there is evidence linking a number of dietary components to CHD risk reduction. The strength of this evidence has prompted various regulatory bodies to advocate diet as the first line of defence for primary prevention of heart disease. It was therefore decided to combine four dietary components that have been shown to lower blood cholesterol concentrations (nuts, plant sterols, viscous fibre and vegetable protein) in a dietary portfolio in order to determine whether the combined effect is additive. In a metabolically-controlled setting this dietary portfolio has proved to be as effective as a starting dose of a first-generation statin cholesterol-lowering medication in reducing the risk of CHD. The dietary portfolio has also been shown to be effective in sustaining a clinically-significant effect in the long term under a 'real-world' scenario. However, success of the diet depends on compliance and despite the accessibility of the foods adherence has been found to vary greatly. Overall, the evidence supports the beneficial role of the dietary portfolio in reducing blood cholesterol levels and CHD risk.

The effect of strawberries in a cholesterol-lowering dietary portfolio.

Effective diets reduce blood lipids and oxidative damage, both of which have been linked to the complications of diabetes and coronary heart disease. Our objective was to assess the effect of adding strawberries, as a source of antioxidants, to improve the antioxidant effect of a cholesterol-lowering diet (dietary portfolio). To this end, 28 hyperlipidemic subjects who had followed the dietary portfolio consisting of soy, viscous fiber, plant sterol, and nuts for a mean of 2.5 years were randomized to receive supplements of strawberries (454 g/d, 112 kcal) or additional oat bran bread (65 g/d, 112 kcal, approximately 2 g beta-glucan) (control) in a randomized 1-month crossover study with a 2-week washout. Strawberry supplementation resulted in a greater reduction in oxidative damage to low-density lipoprotein (LDL) measured as thiobarbituric acid-reactive substances in the LDL fraction (P = .014). At the end of the strawberry period, reductions in LDL cholesterol and in the ratio of total to high-density lipoprotein cholesterol were maintained close to 1-year values at -13.4% +/- 2.1% and -15.2% +/- 1.7%, respectively (P < .001), and were similar to the post-oat bran bread values. Strawberries also improved the palatability of the diet. We conclude that strawberry supplementation reduced oxidative damage to LDL while maintaining reductions in blood lipids and enhancing diet palatability. Added fruit may improve the overall utility of diets designed to lower coronary heart disease risk.