AHA scientific statement: summary of the Scientific Conference on Dietary Fatty Acids and Cardiovascular Health. Conference summary from the Nutrition Committee of the American Heart Association

Gravity-driven syneresis in model low-fat mayonnaise

Low-fat food products often contain natural, edible polymers to retain the desired mouth feel and elasticity of their full-fat counterparts. This type of product, however, can suffer from syneresis: densification due to the expulsion of fluid. Gaining insight into the physical principles governing syneresis in such soft hybrid dispersions remains a challenge from a theoretical perspective, as experimental data are needed to establish a basis. We record non-accelerated syneresis in a model system for low-fat mayonnaise: a colloid polymer mixture, consisting of oil in water emulsion with starch in the aqueous phase. We find the flow rate of expelled fluid to be proportional to the difference in hydrostatic pressure over the system. The osmotic pressure of the added starch, while being higher than the hydrostatic pressure, does not prevent syneresis because the soluble starch is lost to the expelled fluid. From these findings, we conclude that forced syneresis in these systems can be described as a gravity-driven porous flow through the densely packed emulsion, explainable with a model based on Darcy's law.

Projected Long-Chain n-3 Fatty Acid Intake Post-Replacement of Vegetables Oils with Stearidonic Acid-Modified Varieties: Results from a National Health and Nutrition Examination Survey 2003-2008 Analysis

Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) intake is well below the amount recommended by the 2015-2020 Dietary Guidelines for Americans (0.25 g/day), supporting the need for alternative dietary sources. Stearidonic acid (SDA)-enriched soybeans were bioengineered to endogenously synthesize SDA, which can be readily metabolized to EPA in humans; thus, incorporating the derived SDA-enriched soybean oil into the food supply is a potential strategy to increase EPA. We performed a dietary modeling exercise using National Health and Nutrition Examination Survey 2003-2008 repeat 24-h dietary recall data (n = 24,621) to estimate the potential contribution of SDA-enriched oils to total long-chain n-3 fatty acid intake (defined as EPA + DHA + EPA-equivalents) following two hypothetical scenarios: (1) replacement of regular soybean oil with SDA soybean oil and (2) replacement of four common vegetable oils (corn, canola, cottonseed, and soybean) with respective SDA-modified varieties. Estimated median daily intakes increased from 0.11 to 0.16 g/day post-replacement of regular soybean oil with SDA-modified soybean oil, and to 0.21 g/day post-replacement of four oils with SDA-modified oil; the corresponding mean intakes were 0.17, 0.27, and 0.44 g/day, respectively. The percent of the population who met the 0.25 g/day recommendation increased from at least 10% to at least 30% and 40% in scenarios 1 and 2, respectively. Additional strategies are needed to ensure the majority of the US population achieve EPA and DHA recommendations, and should be assessed using methods designed to estimate the distribution of usual intake of these episodically consumed nutrients.

Cardiac Hypertrophy and Brain Natriuretic Peptide Levels in an Ovariectomized Rat Model Fed a High-Fat Diet

BACKGROUND Heart failure in women increases around the time of menopause when high-fat diets may result in obesity. The heart produces brain natriuretic peptide (BNP), also known as B-type natriuretic peptide. This aims of this study were to assess cardiac hypertrophy and BNP levels in ovariectomized rats fed a high-fat diet. MATERIAL AND METHODS Forty-eight female Wistar rats were divided into four groups: sham-operated rats fed a control diet (SC) (n=12); ovariectomized rats fed a control diet (OC) (n=12); sham-operated rats fed a high-fat diet (SF) (n=12); and ovariectomized rats fed a high-fat diet (OF) (n=12). Body weight and blood pressure were measured weekly for 24 weeks. Rats were then euthanized, and plasma samples and heart tissue were studied for gene expression, hydroxyproline levels, and histological examination. RESULTS A high-fat diet and ovariectomy (group OF) increased the weight body and the systolic blood pressure after three months and five months, respectively. Cardiomyocyte hypertrophy was associated with increased expression of ventricular BNP, decreased natriuretic peptide receptor (NPR)-A and increased levels of hydroxyproline and transforming growth factor (TGF)-β. The plasma levels of BNP and estradiol were inversely correlated; expression of estrogen receptor (ER)β and ERα were reduced. CONCLUSIONS The findings of this study showed that, in the ovariectomized rats fed a high-fat diet, the BNP-NPR-A receptor complex was involved in cardiac remodeling. BNP may be a marker of cardiac hypertrophy in this animal model.

Nutrition education for cardiovascular disease prevention in individuals with spinal cord injuries: study protocol for a randomized controlled trial

Background

Individuals with chronic spinal cord injuries (SCIs) have an increased prevalence of cardiovascular disease (CVD) and associated risk factors compared with age-matched control subjects. Exercise has been shown to improve selected CVD risk factors in individuals with SCI, but using nutrition education as an intervention has not been evaluated in this population. This paper describes our research plan for evaluating the effect of nutrition education on individuals with SCI. In the present study, called Eat Smart, Live Better, we are using a randomized controlled design to test an intervention adapted from an existing evidence-based program that showed a positive effect on nutrition knowledge and behavior of older adults from the general population. There will be an inpatient group (n = 100) and a community group (n = 100). The aims of our study are to compare the intervention and control groups for (1) changes in nutritional behavior, nutritional knowledge, and dietary quality by participants in the program; (2) levels of adiposity and metabolic CVD risk factors at 12-month follow-up; and (3) differential effects among individuals with SCI in the acute rehabilitation setting and those living in the community.

Methods/design

This is a randomized controlled trial of nutrition education. The treatment groups receive six nutrition education sessions. The control groups receive the one “standard of care” nutrition lecture that is required by the Commission on Accreditation of Rehabilitation Facilities. Treatment groups include both an inpatient group, comprising patients who have been admitted to an acute rehabilitation facility because of their recent SCI, and an outpatient group, consisting of community-dwelling adults who are at least 1 year after their SCI. A total of 200 participants will be randomized 1:1 to the intervention or control group, stratified by location (acute rehabilitation facility or community dwelling).

Discussion

To our knowledge, this will be the first reported study of nutrition education in individuals with SCI. The low cost and feasibility of the intervention, if shown to improve nutritional behavior, suggests that it could be implemented in rehabilitation facilities across the country. This has the potential of lowering the burden of CVD and CVD risk factors in this high-risk population.

Trial registration

ClinicalTrials.gov, NCT02368405. Registered on February 10, 2015.

Tackling issues in the path toward clinical translation in brain conditioning: Potential offered by nutraceuticals

Brief periods of ischemia have been shown in many experimental setups to provide tolerance against ischemia in multiple organs including the brain, when administered before (preconditioning) or even after (postconditioning) the normally lethal ischemia. In addition to these so-called ischemic conditionings, many pharmacological and natural agents (e.g., chemicals and nutraceuticals) can also act as potent pre- and post-conditioners. Deriving from the original concept of ischemic preconditioning, these various conditioning paradigms may be promising as clinical-stage therapies for prevention of ischemic-related injury, especially stroke. As no proven experimentally identified strategy has translated into clinical success, the experimental induction of neuroprotection using these various conditioning paradigms has raised several questions, even before considering translation to clinical studies in humans. The first aim of the review is to consider key questions on preclinical studies of pre- or post-conditioning modalities including those induced by chemical or nutraceuticals. Second, we make the argument that several key issues can be addressed by a novel concept, nutraceutical preconditioning. Specifically, α-linolenic acid (alpha-linolenic acid [ALA] an omega-3 polyunsaturated fatty acid), contained in plant-derived edible products, is essential in the daily diet, and a body of work has identified ALA as a pre- and post-conditioner of the brain. Nutritional intervention and functional food development are an emerging direction for preventing stroke damage, offering the potential to improving clinical outcomes through activation of the endogenous protective mechanisms known collectively as conditioning.

Nutritional and sensory evaluation of a complementary food formulated from rice, faba beans, sweet potato flour, and peanut oil

BACKGROUND

Childhood malnutrition is a common disorder in developing countries.

OBJECTIVE

To formulate a complementary food from rice, germinated-decoated faba bean, orange-fleshed sweet potato flour, and peanut oil (RFPP formula) for infants aged 6 to 24 months.

METHODS

The nutritional and sensory characteristics of the RFPP complementary food in comparison with those of a commercial complementary food were determined using standard official procedures.

RESULTS

The levels of protein (17.89 g/100 g), fat (10.35 g/100 g), carbohydrate (67.82 g/100 g), and energy (435.99 kcal/100 g) of the RFPP complementary food met the specifications of the Codex standard (1991) and the Egyptian Standard No. 3284 (2005). The essential amino acid contents of the RFPP complementary food were higher than the amino acid profile of the Food and Agriculture Organization/World Health Organization/United Nations University (2002) reference protein for children 0.5 to 1 and 1 to 2 years of age. The RFPP complementary food had high levels (54.00%) of monounsaturated fatty acids. However, the highest level of saturated fatty acids (51.10%) was recorded for the commercial complementary food. The sensory evaluation results, using a nine-point hedonic scale ranging from 1 (dislike extremely) to 9 (like extremely), show that the RFPP complementary food was acceptable in appearance (7.20), color (6.35), aroma (6.75), taste (7.25), and mouthfeel (7.10) and had an overall acceptability of 6.40.

CONCLUSIONS

The RFPP formulated complementary food was acceptable and adequate in nutrients for weaning purposes.

Consumo de carnes por adolescentes do Sul do Brasil

OBJETIVO: Descrever a frequência de consumo de diferentes tipos de carnes conforme variáveis sociodemográficas e nutricionais, e analisar o consumo, em adolescentes do Sul do Brasil, de dieta rica em gordura conforme os tipos de carne consumidos. MÉTODOS: Estudo transversal realizado com adolescentes pertencentes à coorte de nascimentos de 1993, em Pelotas (RS). A frequência de consumo de carnes vermelhas, brancas, vísceras e embutidos foi avaliada por um Questionário de Frequência de Consumo Alimentar, adaptado para este estudo. A ingestão de dieta rica em gordura foi avaliada a partir do instrumento proposto por Block. As variáveis independentes foram sexo, cor da pele, nível socioeconômico, escolaridade materna e estado nutricional. Nas análises estatísticas, foram utilizados testes Qui-quadrado de heterogeneidade e de tendência linear. RESULTADOS: Foram avaliados 4.325 adolescentes com idade média de 14,7, DP=0,3 anos, dos quais 51,2% eram do sexo feminino. A frequência de consumo diário de carnes vermelhas foi maior do que a de carnes brancas (43,0% e 9,7%, respectivamente). O consumo de embutidos por mais do que quatro vezes por semana foi referido por 48,5% dos indivíduos, e 81,4% relataram consumir vísceras raramente ou nunca. Adolescentes de maior nível socioeconômico e filhos de mães com maior escolaridade apresentaram maior consumo de carnes vermelhas e embutidos, enquanto aqueles em situação oposta apresentaram maior consumo de carnes brancas. Adolescentes que consomem carnes com maior frequência também consomem dieta rica em gordura. CONCLUSÃO: As carnes consumidas com maior frequência pelos adolescentes foram as vermelhas e os embutidos. No entanto, adolescentes de maior nível socioeconômico consomem carnes vermelhas com maior frequência, enquanto adolescentes menos favorecidos economicamente consomem mais carnes brancas.

Fatores de risco comportamentais acumulados para doenças cardiovasculares no sul do Brasil

OBJETIVO: Estimar a prevalência e identificar fatores associados ao acúmulo de comportamentos de risco para doenças cardiovasculares entre adultos. MÉTODOS: Estudo transversal de base populacional com amostra representativa de 2.732 adultos de ambos os sexos de Pelotas, RS, em 2010. Os fatores de risco comportamentais investigados foram: tabagismo; inatividade física no lazer; consumo habitual de gordura aparente da carne; e consumo diário de embutidos, carne vermelha e leite integral. O desfecho do estudo foi o escore de aglomeração de fatores de risco comportamentais, variando de zero a três: nenhum fator de risco comportamental para doenças cardiovasculares ou exposição a 1, 2 ou > 3 fatores de risco comportamentais. Realizou-se regressão logística multinomial para avaliar o efeito ajustado das características individuais sobre o acúmulo de fatores de risco comportamentais, tendo como categoria de referência indivíduos sem qualquer dos fatores. RESULTADOS: A inatividade física foi o fator de risco mais prevalente (75,6%), seguido do consumo habitual de gordura aparente da carne (52,3%). Dois terços da população apresentaram dois ou mais fatores de risco comportamentais. A combinação de inatividade física e consumo habitual de gordura aparente da carne ocorreu em 17,5% da amostra; e inatividade física, consumo habitual de gordura aparente da carne e tabagismo, em 6,7%. Os odds ratios de acúmulo de dois ou mais fatores foram maiores entre homens e associaram-se inversamente com o indicador econômico nacional. CONCLUSÕES: O acúmulo de fatores de risco comportamentais para doenças cardiovasculares é elevado na população estudada. São necessárias intervenções públicas capazes de prevenir a ocorrência simultânea desses fatores.

Recommended dietary reference intakes, nutritional goals and dietary guidelines for fat and fatty acids: a systematic review

Dietary fat and its effects on health and disease has attracted interest for research and Public Health. Since the 1980s many bodies and organizations have published recommendations regarding fat intake. In this paper different sets of recommendations are analyzed following a systematic review process to examine dietary reference intakes, nutritional goals and dietary guidelines for fat and fatty acids. A literature search was conducted in relevant literature databases along a search for suitable grey literature reports. Documents were included if they reported information on either recommended intake levels or dietary reference values or nutritional objectives or dietary guidelines regarding fat and/or fatty acids and/or cholesterol intake or if reported background information on the process followed to produce the recommendations. There is no standard approach for deriving nutrient recommendations. Recommendations vary between countries regarding the levels of intake advised, the process followed to set the recommendations. Recommendations on fat intake share similar figures regarding total fat intake, saturated fats andtransfats. Many sets do not include a recommendation about cholesterol intake. Most recent documents provide advice regarding specificn-3 fatty acids. Despite efforts to develop evidence based nutrient recommendations and dietary guidelines that may contribute to enhance health, there are still many gaps in research. It would be desirable that all bodies concerned remain transparent about the development of dietary recommendations. In order to achieve this, the type of evidence selected to base the recommendations should be specified and ranked. Regular updates of such recommendations should be planned.

A review of the evidence for the effects of total dietary fat, saturated, monounsaturated and n-6 polyunsaturated fatty acids on vascular function, endothelial progenitor cells and microparticles

Vascular dysfunction is recognised as an integrative marker of CVD. While dietary strategies aimed at reducing CVD risk include reductions in the intake of SFA, there are currently no clear guidelines on what should replace SFA. The purpose of this review was to assess the evidence for the effects of total dietary fat and individual fatty acids (SFA, MUFA and n-6 PUFA) on vascular function, cellular microparticles and endothelial progenitor cells. Medline was systematically searched from 1966 until November 2010. A total of fifty-nine peer-reviewed publications (covering fifty-six studies), which included five epidemiological, eighteen dietary intervention and thirty-three test meal studies, were identified. The findings from the epidemiological studies were inconclusive. The limited data available from dietary intervention studies suggested a beneficial effect of low-fat diets on vascular reactivity, which was strongest when the comparator diet was high in SFA, with a modest improvement in measures of vascular reactivity when high-fat, MUFA-rich diets were compared with SFA-rich diets. There was consistent evidence from the test meal studies that high-fat meals have a detrimental effect on postprandial vascular function. However, the evidence for the comparative effects of test meals rich in MUFA or n-6 PUFA with SFA on postprandial vascular function was limited and inconclusive. The lack of studies with comparable within-study dietary fatty acid targets, a variety of different study designs and different methods for determining vascular function all confound any clear conclusions on the impact of dietary fat and individual fatty acids on vascular function.

Effects of acute ingestion of different fats on oxidative stress and inflammation in overweight and obese adults

Background

Studies show that obese individuals have prolonged elevations in postprandial lipemia and an exacerbated inflammatory response to high fat meals, which can increase risk for cardiovascular diseases. As epidemiological studies indicate an association between type of fat and circulating inflammatory markers, the purpose of this study was to investigate the acute effect of different fat sources on inflammation and oxidative stress in overweight and obese individuals.

Methods

Eleven overweight and obese subjects consumed three high fat milkshakes rich in monounsaturated fat (MFA), saturated fat (SFA), or long-chain omega 3 polyunsaturated fat (O3FA) in random order. Blood samples collected at baseline, 1, 2, 4, and 6 hours postprandial were analyzed for markers of inflammation (soluble intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), tumor necrosis factor- α (TNF-α), and C-reactive protein (CRP)), oxidative stress (8-epi-prostaglandin-F2α (8-epi) and nuclear factor-κB (NF-κB)), and metabolic factors (glucose, insulin, non-esterified free fatty acids, and triglycerides (TG)).

Results

O3FA enhanced NF-kB activation compared to SFA, but did not increase any inflammatory factors measured. Conversely, SFA led to higher ICAM-1 levels than MFA (p = 0.051), while MFA increased TG more than SFA (p < 0.05). CRP increased while TNF-α and 8-epi decreased with no difference between treatments.

Conclusions

While most of the inflammatory factors measured had modest or no change following the meal, ICAM-1 and NF-κB responded differently by meal type. These results are provocative and suggest that type of fat in meals may differentially influence postprandial inflammation and endothelial activation.

Dietary macronutrient intake and lower urinary tract symptoms in women

PURPOSE

To examine associations between macronutrient and total energy intakes with lower urinary tract symptoms (LUTS) in women.

METHODS

Cross-sectional analysis of 2060 women aged 30-79 years in the population-based Boston Area Community Health Survey (2002-2005). Data were collected by validated food frequency questionnaire and in-person interviews. Outcomes for multivariate logistic regression were moderate-to-severe total LUTS, storage, voiding, and postmicturition symptoms.

RESULTS

Greater total energy intake was positively associated with LUTS, specifically among women with lower waist circumferences (<76 cm, p = .005, p(interaction) = .01). Increased saturated fat intake was associated with postmicturition symptoms (Quintile 5 vs. 1, odds ratio 3.94, 95% confidence interval 1.57-9.89, p(trend) = .04). High protein intake was positively associated with storage symptoms (p(trend) = .03), particularly nocturia. No consistent associations were observed for carbohydrate, monounsaturated, or polyunsaturated fat intakes.

CONCLUSIONS

Among women with low waist circumferences, high total daily calorie intake was associated with moderate-to-severe LUTS. Although greater saturated fat intake was linked to postmicturition symptoms, the possibility that postmicturition symptoms in women represent more extensive or severe conditions should be explored in future research. These novel results indicate that dietary contributors to LUTS in women are distinct from those in men and may depend on symptom subtype and body size.

Dietary strategies to improve nutritional value, oxidative stability, and sensory properties of poultry products

Consumers demand both safer and more nutritious food products exempt of non-natural origin preservatives or other food additives. In this frame, products with lower fat content and/or a higher ratio in unsaturated fatty acids, especially n-3 fatty acids, are desired because these lipids can help prevent the development of cardiovascular and inflammatory pathologies. The intake of meat products is of interest because they are an excellent source of vitamins and minerals. In addition, the shelf-life of meat products can be extended by the presence of natural antioxidants coming from different sources such as plant extracts. Therefore, different strategies have been studied to improve the nutritional value, oxidative stability, and sensory characteristics of meat products and eggs through different mineral and natural dietary supplements. In comparison to other strategies, dietary supplements present the advantage that first the living animals may efficiently distribute the compounds throughout the tissues and second, the dietary supplementation is safer because the resulting enriched meat products and eggs ensure tolerable amounts in humans. Poultry meats and eggs are widely consumed and their fatty acid profile and tocopherol content can be easily modified through different dietary strategies thus being excellent models to improve their nutritional value and oxidative stability.

Dietary macronutrient and energy intake and urinary incontinence in women

Weight loss involving diet modification improves urinary incontinence (UI) in women, but little is known about dietary correlates of UI. The authors examined intakes of total energy, carbohydrate, protein, and fats in relation to UI in a cross-sectional sample of 2,060 women in the population-based Boston Area Community Health Survey (2002-2005). Data were collected from in-person home interviews and food frequency questionnaires. Logistic regression was used to calculate odds ratios and 95% confidence intervals for the presence of moderate-to-severe UI; a severity index was analyzed in secondary analysis of 597 women with urine leakage. Greater total energy intake was associated with UI (P(trend) = 0.0001; highest quintile vs. lowest: adjusted odds ratio = 2.86, 95% confidence interval: 1.56, 5.23) and increased severity. No associations were observed with intake of carbohydrates, protein, or total fat. However, the ratio of saturated fat intake to polyunsaturated fat intake was positively associated with UI (highest quintile vs. lowest: adjusted odds ratio = 2.48, 95% confidence interval: 1.22, 5.06) and was strongly associated with severity (P(trend) < 0.0001). Results suggest that dietary changes, particularly decreasing saturated fat relative to polyunsaturated fat and decreasing total calories, could independently account for some of the benefits of weight loss in women with UI.

Plasma free fatty acid patterns and their relationship with CVD risk in a male middle-aged population

BACKGROUND/OBJECTIVES

The role of individual fatty acids in the development of cardiovascular disease (CVD) is well established, but the effects of an overall pattern of fatty acids in CVD risk has yet to be elucidated. Circulating fatty acid levels are related to metabolic disturbances associated with the metabolic syndrome and CVD, due to disturbances in the activity of enzymes that catalyse fatty acid desaturation (Delta-desaturases). Therefore, we determined patterns of fatty acids and estimated desaturase activity in plasma and analysed how these patterns were related to a 10-year CVD risk estimates in a middle-aged male population in Northern Ireland.

SUBJECTS/METHODS

Principal components analysis (PCA) was performed for defining fatty acid patterns in 379 men aged 30-49 years. Logistic regression analyses were then carried out for analysing the relationship between these fatty acid patterns and the 10-year CVD risk estimates.

RESULTS

The PCA generated three high fatty acid patterns: high saturated fatty acid (SFA), high omega 3 fatty acid (omega 3) and high monosaturated fatty acid (MNFA). Results from logistic regression analyses show that a 1 s.d. increase in the SFA pattern score was significantly and positively associated with an increase in the 10-year CVD risk category (odds ratio 1.71, 95% confidence interval 1.33-2.21, P<0.0001) even after adjustment for lifestyle factors. There were no significant relationships between the other two pattern scores and the 10-year CVD risk.

CONCLUSIONS

An unhealthy fatty acid pattern representing both dietary intake and in vivo fatty acid metabolism is related to the 10-year CVD risk estimates and provide evidence that, as with dietary patterns, the synergistic effect of multiple fatty acids may be more important in relation to the development of CVD risk.

n-3 PUFA fortification of high n-6 PUFA farmed tilapia with linseed could significantly increase dietary contribution and support nutritional expectations of fish

Farmed fish high in n-6 PUFA may undermine fish nutritional expectations and intake recommendations for n-3 PUFA requirements and exacerbate rather than improve already high n-6/n-3 PUFA diets. Dietary contribution of fish fortification by linseed-based n-3 PUFA was evaluated. Mango tilapia (12 months old) with high n-6 PUFA (21.8 FA%, n-6/n-3 ratio 4.6:1) were fed standard/control (T(C)) or linseed-supplemented (5%, T(5%); 7%, T(7%)) feed for 61 days regular-growth and 120 days stock-growth (to 650 g). Compared to T(C), n-3 PUFA increased in T(5%) 46% and T(7%) 58%; ALA in T(5%) increased 100% and T(7%) 167%; EPA+DHA in T(5%) increased 14% and T(7%) 23% (p < 0.05); n-6 PUFA/LCPUFA were unchanged. T(7%) EPA+DHA 168 mg/100 g of raw fillet is comparable to current American intake and Dietary Reference Intakes; controlled cooking preserved approximately 90% EPA+DHA. n-6/n-3 ratios decreased 16-38% in total PUFA to 2.3:1 and in LCPUFA to 0.61:1. Linseed supplementation could improve tilapia n-3 PUFA/LCPUFA, ameliorating n-3 PUFA scarcity and unexpectedly high fish n-6 PUFA content, potentially making a significant nutritional contribution.

Are soy foods protective against ischemic stroke?

Ischemic stroke is one of the leading causes of mortality and morbidity in the world. A large number of studies have observed the beneficial effects of soy protein and soy polyunsaturated fat in lowering blood cholesterol, reducing blood pressure and improving cardiovascular health. This study aims to investigate the potential of a soy food diet in the prevention of ischemic stroke through evaluation of evidence from clinical trials, meta-analyses, experimental and epidemiological studies.

Diet, serum homocysteine levels and ischaemic heart disease in a Mediterranean population

Homocysteine (Hcy) is recognised as a risk factor for IHD. Serum Hcy is negatively correlated with serum folate levels, the main sources of which are fruits, vegetables and legumes. The present case–control study was designed to examine the relationship between serum Hcy levels and IHD and to assess the role of dietary factors in the southern Mediterranean population of Crete, Greece. Serum Hcy, folate, vitamin B12, creatinine and glucose levels and a full lipid profile were measured in 152 patients with established IHD, median age 64 (range 33–77) years, and 152 healthy control subjects, age- and sex-matched. Dietary data were assessed using a 3 d food intake record. Compared with controls, patients with IHD had significantly higher daily intakes of vitamin B12and MUFA and significantly lower intakes of carbohydrate, fibre, folate, cholesterol,n-3 fatty acids and totaltransunsaturated fatty acids. Moreover, patients had significantly higher serum Hcy, vitamin B12and creatinine levels, but significantly lower folate. Serum folate concentrations in both groups had a significant positive correlation with dietary fibre consumption and a significant inverse correlation with vitamin B12intake. IHD patients should be encouraged to increase their daily dietary intake of fibre, folate andn-3 fatty acids, which are significant components of the traditional Cretan Mediterranean diet. Where dietary folate intake is inadequate, folate supplements are recommended to reduce elevated Hcy levels.

Obesity in HIV-infection: dietary correlates

OBJECTIVE

To describe the prevalence of obesity among a cohort of individuals living with HIV infection, and to determine differences in dietary intake among those subjects who are normal weight, overweight, and obese.

DESIGN

A cross-sectional study among participants enrolled in the Nutrition for Healthy Living (NFHL) study.

SETTING

Eligible participants included HIV-positive adults living in the greater Boston, MA and Providence, RI, areas. Subjects and Measures of Outcome: In total, 321 (265 males, 56 females) subjects were studied. Body composition measurements, demographic and health data, and fasting blood samples were analyzed. Dietary intake was assessed by three-day food records. Statistical analyses were performed using Statistical Package for Social Science (SPSS).

RESULTS

13% of males and 29% females were found to be obese. Energy intake per kilogram decreased by body mass index (BMI) category for both men and women (p <0.05). Although not different between groups, mean total fat and saturated fat intakes were above recommendations for both men and women in all BMI categories, while total grams dietary fiber decreased as BMI increased. Individuals in all BMI groups had micronutrient intakes below the Dietary Reference Intakes. Serum markers of insulin resistance were significantly different by BMI category among men and women, as well as triglycerides and total cholesterol for the males.

CONCLUSIONS

Obesity and diet in individuals living with HIV-infection needs to be addressed, as quality of dietary intake may have future implications regarding cardiovascular disease, metabolic syndrome, and other health risks associated with overweight and obesity.

Features of the metabolic syndrome are modulated by an interaction between the peroxisome proliferator-activated receptor-delta −87T>C polymorphism and dietary fat in French-Canadians

OBJECTIVE

We verified whether genetic variants in this gene are associated with the MS and whether dietary fatty acids interact with the -87T>C polymorphism.

METHODS

By direct sequencing, we identified 15 variants in the PPAR-delta gene and analyses were pursued with the -87T>C polymorphism for 340 subjects.

RESULTS

Metabolic variables were comparable among each genotype group. The -87T>C polymorphism, fat intake and the interaction accounted, respectively for 2.2, 1.9 and 1.5% of the variance in high-density lipoprotein cholesterol (HDL-C) levels (P<0.05) (age, sex and energy intake were included into the model). The total cholesterol/HDL-C ratio was also modulated by a gene-diet interaction and by the -87T>C polymorphism (P<0.05). No gene-diet interaction effects were observed for other features of the MS. The age- and sex-adjusted odds ratio (OR) of exhibiting three or more features of the MS when carrying the -87C allele was 0.62 (P=0.04) compared to -87T/T. However, in subjects consuming less than 34.4% of energy from fat (median of fat consumption), the OR in carriers of the -87C allele was of 0.42 (P=0.008).

CONCLUSION

These data suggest that the PPAR-delta -87T>C polymorphism may be associated with a lower risk to exhibit the MS and this association is influenced by dietary fat intake. The metabolic syndrome (MS) is influenced by genetic and environmental factors. Peroxisome proliferator-activated receptor delta (PPAR-delta), a transcription factor involved in lipid metabolism, is a candidate gene for the MS.

n-3 Fatty acids from fish or fish-oil supplements, but not alpha-linolenic acid, benefit cardiovascular disease outcomes in primary- and secondary-prevention studies: a systematic review

Studies on the relation between dietary n-3 fatty acids (FAs) and cardiovascular disease vary in quality, and the results are inconsistent. A systematic review of the literature on the effects of n-3 FAs (consumed as fish or fish oils rich in eicosapentaenoic acid and docosahexaenoic acid or as alpha-linolenic acid) on cardiovascular disease outcomes and adverse events was conducted. Studies from MEDLINE and other sources that were of > or =1 y in duration and that reported estimates of fish or n-3 FA intakes and cardiovascular disease outcomes were included. Secondary prevention was addressed in 14 randomized controlled trials (RCTs) of fish-oil supplements or of diets high in n-3 FAs and in 1 prospective cohort study. Most trials reported that fish oil significantly reduced all-cause mortality, myocardial infarction, cardiac and sudden death, or stroke. Primary prevention of cardiovascular disease was reported in 1 RCT, in 25 prospective cohort studies, and in 7 case-control studies. No significant effect on overall deaths was reported in 3 RCTs that evaluated the effects of fish oil in patients with implantable cardioverter defibrillators. Most cohort studies reported that fish consumption was associated with lower rates of all-cause mortality and adverse cardiac outcomes. The effects on stroke were inconsistent. Evidence suggests that increased consumption of n-3 FAs from fish or fish-oil supplements, but not of alpha-linolenic acid, reduces the rates of all-cause mortality, cardiac and sudden death, and possibly stroke. The evidence for the benefits of fish oil is stronger in secondary- than in primary-prevention settings. Adverse effects appear to be minor.

Composition, structure and absorption of milk lipids: a source of energy, fat-soluble nutrients and bioactive molecules

Milkfat is a remarkable source of energy, fat-soluble nutrients and bioactive lipids for mammals. The composition and content of lipids in milkfat vary widely among mammalian species. Milkfat is not only a source of bioactive lipid components, it also serves as an important delivery medium for nutrients, including the fat-soluble vitamins. Bioactive lipids in milk include triacylglycerides, diacylglycerides, saturated and polyunsaturated fatty acids, and phospholipids. Beneficial activities of milk lipids include anticancer, antimicrobial, anti-inflammatory, and immunosuppression properties. The major mammalian milk that is consumed by humans as a food commodity is that from bovine whose milkfat composition is distinct due to their diet and the presence of a rumen. As a result of these factors bovine milkfat is lower in polyunsaturated fatty acids and higher in saturated fatty acids than human milk, and the consequences of these differences are still being researched. The physical properties of bovine milkfat that result from its composition including its plasticity, make it a highly desirable commodity (butter) and food ingredient. Among the 12 major milk fatty acids, only three (lauric, myristic, and palmitic) have been associated with raising total cholesterol levels in plasma, but their individual effects are variable-both towards raising low-density lipoproteins and raising the level of beneficial high-density lipoproteins. The cholesterol-modifying response of individuals to consuming saturated fats is also variable, and therefore the composition, functions and biological properties of milkfat will need to be re-evaluated as the food marketplace moves increasingly towards more personalized diets.

Physiological studies of eicosapentaenoic acid production in the marine microalga Glossomastix chrysoplasta

We describe the characterization of the microalga Glossomastix chrysoplasta, an eicosapentaenoic acid (EPA) producer in the Pinguiophyceae class, Chromophyte division. Growth conditions were selected to optimize algal growth and EPA production. EPA represented up to 30% of the fatty acid content of Glossomastix chrysoplasta, at levels of 22 mg EPA per gram dry weight. Up to 72% of the EPA was produced as glycolipids, components of structural lipids. The optimal growth conditions in continuous culture were found to be greater than 500 micromol photons/m(2) . s light intensity, 0.33/day dilution rate, pH 7.20-7.45, and a temperature of 18-20 degrees C. Macronutrient studies indicated the limiting nutrient to be bicarbonate or dissolved carbon dioxide, and consequently decreasing pH increased EPA production.

Carbohydrate intake is correlated with biomarkers for coronary heart disease in a population of overweight premenopausal women

The associations between macronutrient intake and plasma parameters associated with increased risk for coronary heart disease (CHD) were evaluated in 80 overweight premenopausal women. We hypothesized that higher carbohydrate intake would be associated with a more detrimental plasma lipid profile. Dietary data were collected using a validated food frequency questionnaire (FFQ). Plasma total cholesterol (TC), triglycerides (TGs), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were determined from two fasting blood samples. In addition, selected apolipoproteins (apo) and LDL peak size were measured. Values for TC, TG and HDL were not in the range of risk classification; however, the mean values of LDL-C, 2.7 +/- 0.7 mmol/L, were higher than the current recommendations. Carbohydrate intake was positively associated with TG and apo C-III (P < .01) concentrations, and negatively associated with LDL diameter (P < .01). Participants were divided into low (<53% of energy) or high (> or = 53% energy) carbohydrate intake groups. Individuals in the <53% carbohydrate group consumed more cholesterol and total fat, but also had higher intake of polyunsaturated and monounsaturated fatty acids (SFAs). In contrast, subjects in the > or =53% group consumed higher concentrations of glucose and fructose than those in the low-carbohydrate (LC) group. In addition, subjects consuming <53% carbohydrate had lower concentrations of LDL-C and apo B (P < .01) and a larger LDL diameter (P < .05) than the > or =53% group. These results suggest that the lower LDL-C in the LC group may be related to both the amount of carbohydrate and the type of fatty acids consumed by these subjects.

Association between the PPARalpha-L162V polymorphism and components of the metabolic syndrome

Genetic factors, alone or in interaction with components of the diet, are thought to be involved in the development of the metabolic syndrome. The objective of our study was first to compare the frequency of the peroxisome proliferator-activated receptor (PPAR)alpha-L162V polymorphism in a sample of men with and without the metabolic syndrome as defined by the National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATPIII) guidelines, and secondly, to evaluate gene-diet interaction effects on features of the metabolic syndrome. The PPARalpha-L162V genotype was determined in a sample of 632 men by a polymerase chain reaction-restriction length polymorphism (PCR-RFLP)-based method; fat as well as saturated fat intakes were evaluated by a dietitian-administered food frequency questionnaire. The frequency of the V162 allele was similar in men with ( n=281) and without ( n=351) the metabolic syndrome ( chi(2)=0.03, p=0.84) but was higher in subjects having simultaneously abdominal obesity, hypertriglyceridemia, and low high-density lipoprotein cholesterol (HDL-C) levels ( chi(2)=3.73, p=0.05). Carriers of the V162 were characterized by higher plasma apolipoprotein B and triglyceride (TG) levels ( p=0.10, p=0.004). In a model including the PPARalpha-L162V polymorphism, fat or saturated fat, its interaction, and covariates (smoking habits, and energy and alcohol intake), the interaction explained a significant percentage of the variance observed in waist circumference ( p<0.05). In conclusion, the PPARalpha-L162V polymorphism alone or in interaction with dietary fat intake is associated with components of the metabolic syndrome.

Monounsaturated fatty acid intake by children and adults: temporal trends and demographic differences

Epidemiologic evidence suggests that dietary monounsaturated fatty acids (MUFA) may have a beneficial health effect. Twenty-four-hour dietary intake data collected on 10-year-olds from 1978 to 1994 and on children and adults (ages 0-30 years) were examined for time, age, gender, ethnic, and geographic location differences in MUFA intake. Children's percent energy from MUFA decreased significantly from 1978 (14.1%) to 1994 (11.9%) with intake of oleic acid decreasing from 33.9 g/day (1973) to 25.7 g/day (1994). In 1994-96, percent energy from MUFA was 13% for children and adults aged 12 to 30 years, with 5% from palmitoleic acid and 93% from oleic acid. Males and blacks had significantly higher MUFA intake across all age groups than females and whites. Intakes of MUFA increased from 0 to 11 years of age to young adulthood (12-19 years), with no further increase at 20 to 30 years of age. Intakes of MUFA were lowest in the Northeast and highest in the Midwest. There were differences in food sources of MUFA by age group. For children 0 to 5 years of age, major sources were whole milk, peanut butter, 2% milk, and French fries; for children 6 to 11 years of age, major sources were whole milk, peanut butter, French fries, and 2% milk; for children 12 to 19 years of age, French fries, salt snacks, whole milk, and meat pizza were the major sources; for adults, French fries, whole milk, potato chips, and ground beef were the most common sources of MUFA. U.S. children and adults displayed temporal trends and demographic differences in intakes and food sources of MUFA. The implications of these changes and differences on biologic risk factors for specific chronic diseases warrant further investigation.

Sugars and starch in the nutritional management of diabetes mellitus

Nutritional recommendations, long recognized as an important aspect of diabetes mellitus treatment, have also been an area of persistent controversy, particularly regarding the proportions and types of carbohydrate and fat. This review addresses the role of sugars within medical nutrition therapy for diabetes mellitus. Nutritional recommendations for diabetes mellitus treatment were revised recently. The new guidelines do not specifically restrict intake of sugars, although general recommendations are made for including fiber, whole grains, vegetables, and fruits within dietary selections containing starches. For carbohydrates, the principle focus is on overall caloric amounts. In type 1 diabetes the most effective approach to the control of postprandial hyperglycemia continues to be adjustment of premeal doses of insulin on the basis of carbohydrate counting. In type 2 diabetes, in addition to a focus on caloric content of carbohydrate, consideration continues to be given to the role of the glycemic index as a determinant of postprandial hyperglycemia and overall metabolic control. Nevertheless, consensus recommendations do not support widespread use of the glycemic index. An area of some change is a more clear endorsement of including monounsaturated fatty acids. Current recommendations are that monounsaturated fatty acids and carbohydrates combined should provide 60-70% of daily energy intake, with individual flexibility in the respective proportions, whereas intake of saturated fats is limited to < 10% of energy intake. This new emphasis reflects greater awareness of the importance of responding to individual and cultural dietary preferences and the need to address treatment of both hyperglycemia and dyslipidemia in diabetes mellitus.

Fatty acid composition of skeletal muscle reflects dietary fat composition in humans

BACKGROUND

It is still unknown whether the fatty acid composition of human skeletal muscle lipids is directly influenced by the fat composition of the diet.

OBJECTIVE

We investigated whether the fatty acid composition of the diet is reflected in the fatty acid profile of skeletal muscle phospholipids and triacylglycerols.

DESIGN

Thirty-two healthy adults (25 men and 7 women) included in a larger controlled, multicenter dietary study were randomly assigned to diets containing a high proportion of either saturated fatty acids (SFAs) [total fat, 36% of energy; SFAs, 18% of energy; monounsaturated fatty acids (MUFAs), 10% of energy] or MUFAs (total fat, 35% of energy; SFAs, 9% of energy; MUFAs, 19% of energy) for 3 mo. Within each diet group, there was a second random assignment to supplementation with fish oil capsules [containing 3.6 g n-3 fatty acids/d; 2.4 g eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3)] or placebo. A muscle biopsy sample was taken from the vastus lateralis muscle after the diet period. Parallel analyses of diet and supplementation effects were performed.

RESULTS

The proportions of myristic (14:0), pentadecanoic (15:0), heptadecanoic (17:0), and palmitoleic (16:1n-7) acids in the skeletal muscle phospholipids were higher and the proportion of oleic acid (18:1n-9) was lower in the SFA group than in the MUFA group. The proportion of total n-3 fatty acids in the muscle phospholipids was approximately 2.5 times higher, with a 5 times higher proportion of eicosapentaenoic acid (20:5n-3), in subjects supplemented with n-3 fatty acids than in those given placebo. Similar differences were observed in the skeletal muscle triacylglycerols.

CONCLUSION

The fatty acid composition of skeletal muscle lipids reflects the fatty acid composition of the diet in healthy men and women.

Childhood obesity: public-health crisis, common sense cure

During the past two decades, the prevalence of obesity in children has risen greatly worldwide. Obesity in childhood causes a wide range of serious complications, and increases the risk of premature illness and death later in life, raising public-health concerns. Results of research have provided new insights into the physiological basis of bodyweight regulation. However, treatment for childhood obesity remains largely ineffective. In view of its rapid development in genetically stable populations, the childhood obesity epidemic can be primarily attributed to adverse environmental factors for which straightforward, if politically difficult, solutions exist.

Dietary fats and diabetes mellitus: is there a good fat?

As knowledge of the fatty acid functions has increased, so has the complexity of making dietary fat recommendations to people with type 2 diabetes. Oleic acid seems to offer a slight advantage over linoleic acid in reducing plasma glucose, insulin levels, total cholesterol, low-density lipoproteins (LDLs), and triglycerides, but may also have atherogenic properties through another mechanism. A diet containing a higher proportion of polyunsaturated fatty acids (PUFAs) may require a concomitant increase in antioxidant intake because PUFAs oxidize easily and are then converted to oxidized LDL, which is more atherogenic. In addition to raising total and LDL cholesterol, long chain saturated free fatty acids may interact with plasma glucose to increase insulin secretion. Omega-3 fatty acids decrease triglycerides and reduce the risk of fatal cardiac arrhythmias. Glycemic control does not appear to be adversely affected by omega-3 fatty acids at amounts of up to 3 g/d.