Very low intakes of N-3 fatty acids incorporated into bovine milk reduce plasma triacylglycerol and increase HDL-cholesterol concentrations in healthy subjects

Omega 3 Fatty Acids and Health: The Little We Know after All These Years

Elagizi et al. [1] provide an update on the effects of long-chain omega 3 fatty acids on the cardiovascular system [...].

Effects of 12-Week Multivitamin and Omega-3 Supplementation on Micronutrient Levels and Red Blood Cell Fatty Acids in Pre-menopausal Women

The purpose of this study was to validate the efficacy of a customized vitamin-mineral supplement on blood biomarkers in pre-menopausal females. Women (21-40 years old) who were apparently healthy were recruited from the local community (ClinicalTrials.gov trial registration NCT03828097). Pretesting (PRE) occurred in the morning 5 ± 2 days following each participant's menses and involved a fasted blood draw, body mass assessment, and blood pressure assessment. Participants were then randomly assigned in a double-blinded fashion to either the multivitamins (MV) (n = 43) or placebo group (n = 51). Participants consumed two capsules per day with breakfast for 12 weeks. Following the trial, participants reported to the laboratory for POST assessments, which replicated PRE procedures. Red blood cell fatty acid and serum micronutrient analyses were performed in a blinded fashion at hematology laboratories. A group × time interaction was observed for serum vitamin D levels (p < 0.001). MV increased levels from PRE to POST (+43.7%, p < 0.001), whereas no change occurred in the placebo group. Additionally, 78% of MV participants at PRE exhibited inadequate vitamin D levels (<40 ng/dl), whereas only 30% exhibited levels below this threshold at POST. An interaction was also observed for serum folate levels (p < 0.001). MV increased serum folate from PRE to POST (p < 0.001), whereas no change occurred in the placebo group. Red blood cell omega-3 fatty acid content increased from PRE to POST in the MV group (p < 0.001) and placebo group (p < 0.05), although POST values were greater in the MV group (p < 0.001). An interaction was observed for serum HDL cholesterol levels (p = 0.047), and a non-significant increase in this variable from PRE to POST occurred in the MV group (p = 0.060). Four-day food recalls indicated MV increased intake of omega-3 fatty acids, vitamin D, folate, and other micronutrients. In summary, MV supplementation increased serum vitamin D, serum folate, and red blood cell omega-3 fatty acid levels. However, these data are limited to healthy females, and more research is needed to examine if MV can affect metabolic disturbances in individuals with micronutrient deficiencies.

Addition of Olive Leaf Extract to a Mixture of Algae and Extra Virgin Olive Oils Decreases Fatty Acid Oxidation and Synergically Attenuates Age-Induced Hypertension, Sarcopenia and Insulin Resistance in Rats

Olive-derived products, such as virgin olive oil (EVOO) and/or olive leaf extracts (OLE), exert anti-inflammatory, insulin-sensitizing and antihypertensive properties and may be useful for stabilizing omega 3 fatty acids (n-3 PUFA) due to their high content in antioxidant compounds. In this study, the addition of OLE 4:0.15 (w/w) to a mixture of algae oil (AO) rich in n-3 PUFA and EVOO (25:75, w/w) prevents peroxides formation after 12 months of storage at 30 °C. Furthermore, the treatment with the oil mixture (2.5 mL/Kg) and OLE (100 mg/Kg) to 24 month old Wistar rats for 21 days improved the lipid profile, increased the HOMA-IR and decreased the serum levels of miRNAs 21 and 146a. Treatment with this new nutraceutical also prevented age-induced insulin resistance in the liver, gastrocnemius and visceral adipose tissue by decreasing the mRNA levels of inflammatory and oxidative stress markers. Oil mixture + OLE also attenuated the age-induced alterations in vascular function and prevented muscle loss by decreasing the expression of sarcopenia-related markers. In conclusion, treatment with a new nutraceutical based on a mixture of EVOO, AO and OLE is a useful strategy for improving the stability of n-3 PUFA in the final product and to attenuate the cardiometabolic and muscular disorders associated with aging.

Functional and Oxidative Quality Characterization of Spray-Dried Omega-3-Enriched Milk Powder

In the present study, fish oil (FO) and wall material were supplemented to milk to produce spray-dried powder (SDP). Furthermore, the mandate of the study was to enlighten the effect of spray-drying (SD) operating conditions on functional and oxidative quality of produced SDP samples. Purposefully, the cow milk was supplemented with 3% FO as omega-enriched source of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) for development of milk and FO blends (MFOBs). The lecithin was used as an emulsifier and maltodextrin was supplemented as the wall material (WM) in the MFOBs. Initially, the FO, milk fat (MF), and MFOB samples were characterized for EPA, DHA, and peroxide value (PV) before the SD. The SD of MFOB samples was carried out to produce SDP samples by using a mini spray dryer. Central composite design (CCD) with face-centered rotation was used to optimize SD independent conditions such as inlet air temperature (IAT), pump speed (PS), maltodextrin percentage (MD), and needle speed (NS) in the ranges of 160–200°C, 3–9 mL/min, 10–30%, and 5–9 s, respectively. The encapsulation efficiency (EE) ranged between 89.30 and 81.57%. The EPA and DHA retentions were in the ranges of 2.19–1.87 g/100 g and 3.20–2.75 g/100 g, respectively. The highest results for responses were observed on the following conditions: IAT was 160°C, PS was 9 mL/min, MD was 30%, and NS was 9 s, respectively; the minimum values of response factors were obtained on the following conditions: IAT was 200°C, PS was 3 mL/min, MD was 10%, and NS was 5 s, respectively. The percent losses of EPA and DHA were noted in the range of 2–18%. The IAT was observed as main factor for FA reduction in SDP samples. The SDP samples were stable, and low rate of peroxide values was noted. Overall, spray drying can be potentially used to incorporate the essential fatty acids in milk to produce stable SDP for food applications.

Major dietary patterns in relation to age-related cataract

BACKGROUND AND AIMS

Dietary pattern (DP) may play an important role in the formation of Age-related cataract (ARC). The objective of the study was to investigate the association between DP and ARC.

METHODS

Participants (120 cases and 240 controls) aged 50-80 years were selected from the ophthalmology clinic of Urmia Imam Khomeini Educational Hospital in the Northwest of Iran by the simple random sampling method between 2017 and 2018. Participants in matched case-control study were free of diabetes, autoimmune diseases and cancer. Factor analysis method was used to identify the major DPs. The association between participants' DPs and ARC were evaluated using logistic regression analysis in SPSS20.

RESULTS

Four major DPs were found and nominated: "Unhealthy", "Healthy", "Salty foods" and "Mixed" patterns. In continues model the Unhealthy pattern was positively associated with the risk of ARC disease (odds ratio in adjusted model was 5.71; 95% CI: 3.68-8.87, P _trend< 0.001). The Healthy pattern was inversely associated with the ARC (odds ratio in adjusted model was 0.48; 95% CI: 0.34-0.67, P_trend = 0.02). The Salty foods pattern was associated with ARC (odds ratio in adjusted model was 1.45; 95% CI; 1.04-2.02, P_trend = 0.03). The association between ARC disease and Mixed patterns was not statistically significant.

CONCLUSION

The results indicate that Unhealthy and Salty foods patterns were associated with increased risk of ARC. Further prospective studies are needed to confirm such an association.

Fatty Acids and Cardiovascular Risk. Evidence, Lack of Evidence, and Diligence

One of the most controversial areas of nutrition research relates to fats, particularly essential fatty acids, in the context of cardiovascular disease risk. A critical feature of dietary fatty acids is that they incorporate into the plasma membrane, modifying fluidity and key physiological functions. Importantly, they can reshape the bioavailability of eicosanoids and other lipid mediators, which direct cellular responses to external stimuli, such as inflammation and chronic stress conditions. This paper provides an overview of the most recent evidence, as well as historical controversies, linking fat consumption with human health and disease. We underscore current pitfalls in the area of fatty acid research and critically frame fatty acid intake in the larger context of diet and behavior. We conclude that fundamental research on fatty acids and lipids is appropriate in certain areas, but the rigor and reproducibility are lacking in others. The pros and cons are highlighted throughout the review, seeking to guide future research on the important area of nutrition, fat intake, and cardiovascular disease risk.

Health Beneficial Food Emulsifier Produced from Fishery Byproducts

The bioavailability of DHA-bound phospholipids, especially the DHA-bound lysophospholipid (DHA-LPL) could be considered the most effective DHA chemical forms for DHA accretion in the brain. Such a DHA-LPL should also have very high emulsifying stability performance based on its analogy with conventional soy LPL. Therefore, in this study, we describe two fishery byproducts, rich in DHA-bound phospholipids, to derive DHA-LPL via sn-1 positional specific lipase partial hydrolysis of the phospholipids. Through this reaction, the DHA composition increased to 43.8 % from 29.1 % in the salmon head phospholipid-derived DHA-LPL, and to 84.0 % from 47.4 % in the squid meal phospholipid-derived DHA-LPL. In fact, these obtained DHA-LPLs exhibited far higher emulsifying stability than the conventional food emulsifiers in the market. For example, the prepared high-purity squid meal phospholipid-derived LPL sustained an emulsion form for a week even under 80°C. Thus, food emulsifiers produced from fishery byproducts are considered to exhibit very high values of both in a sense of outstandingly high health benefits and sustaining emulsions even under very high temperatures.

Polyphenol-based nutraceuticals for the prevention and treatment of cardiovascular disease: Review of human evidence

BACKGROUND

In addition to prescription drugs, nutraceuticals/functional foods/medical foods are being increasingly added as adjunct treatment of cardiovascular disease (CVD), even though most of them have been exclusively studied in vitro.

HYPOTHESIS/PURPOSE

We review the available evidence (focusing on when the amount of polyphenols' intake was measured) coming from randomized controlled trials (RCTs) of (poly)phenol-based supplements.

CONCLUSION

We conclude that (poly)phenol-based nutraceuticals and functional foods might be indeed used as adjunct therapy of CVD, but additional long-term RCTs with adequate numerosity and with clinically relevant end points are needed to provide unequivocal evidence of their clinical usefulness.

Dietary supplementation with omega-3 fatty acids and oleate enhances exercise training effects in patients with metabolic syndrome

OBJECTIVE

We studied the effects of exercise training alone or combined with dietary supplementation of omega-3 polyunsaturated fatty acids (Ω-3PUFA) and oleate on metabolic syndrome (MSyn) components and other markers of cardiometabolic health.

METHODS

Thirty-six patients with MSyn underwent 24 weeks of high-intensity interval training. In a double-blind randomized design, half of the group ingested 500 mL/day of semi-skim milk (8 g of fat; placebo milk) whereas the other half ingested 500 mL/day of skim milk enriched with 275 mg of Ω-3PUFA and 7.5 g of oleate (Ω-3 + OLE).

RESULTS

Ω-3 + OLE treatment elevated 30% plasma Ω-3PUFA but not significantly (P = 0.286). Improvements in VO2peak (12.8%), mean blood pressure (-7.1%), waist circumference (-1.8%), body fat mass (-2.9%), and trunk fat mass (-3.3%) were similar between groups. However, insulin sensitivity (measured by intravenous glucose tolerance test), serum concentration of C-reactive protein, and high-density lipoprotein improved only in the Ω-3 + OLE group by 31.5%, 32.1%, and 10.3%, respectively (all P < 0.05). Fasting serum triacylglycerol, glucose, and plasma fibrinogen concentrations did not improve in either group after 24 weeks of intervention.

CONCLUSIONS

Diet supplementation with Ω-3PUFA and oleate enhanced cardiometabolic benefits of intense aerobic exercise training in patients with MSyn.

Daily Intake of Milk Enriched with n-3 Fatty Acids, Oleic Acid, and Calcium Improves Metabolic and Bone Biomarkers in Postmenopausal Women

OBJECTIVE

Nutritional strategies can be effective for the prevention of menopause-related diseases, such as osteoporosis and cardiovascular disease. Our aim was to evaluate the effects of a dairy product enriched in polyunsaturated fatty acids, calcium, oleic acid, and vitamins on cardiovascular markers and bone metabolism in postmenopausal women with moderate cardiovascular risk.

METHODS

One hundred seventeen healthy postmenopausal women (aged 45 ± 7.7 years) were allocated to 2 groups: the intervention group (IG; n = 63), who consumed 0.5 L/day of a low-lactose skimmed milk enriched with 40 mg/100 mL of eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA), 0.54 g/100 mL oleic acid, and vitamins, and the control group (CG; n = 54), who consumed 0.5 L/day of semiskimmed milk 0.5 L/day enriched with vitamins A and D.

RESULTS

After 12 months, in the IG there was an improvement in lipid profile: a -5.78% decrease in total cholesterol (p = 0.010), -9.79% (p = 0.004) in low-density lipoprotein (LDL) cholesterol, -9.56% (p < 0.001) in total cholesterol (TC)/high-density lipoprotein (HDL) ratio, and -3.38% in LDL/HDL ratio (p < 0.001). No changes were observed in the CG. In the IG we observed a decrease of -28.20% in high-sensitivity C-reactive protein (hs-CRP; p = 0.012). There was no effect on bone turnover markers or serum osteoprotegerin (OPG) in either of the study groups. In the IG, receptor activator of nuclear factor κB ligand (RANKL) was reduced -17.64% (p = 0.003), with no effect in the CG.

CONCLUSION

In postmenopausal women with moderate cardiovascular risk, dietary supplementation with a dairy drink enriched with fatty acids (EPA+DHA), oleic acid, minerals, and vitamins induces a positive effect on cardiovascular risk and parameters of bone metabolism. Its regular consumption may be a useful nutritional support for postmenopausal women.

Local false discovery rate estimation using feature reliability in LC/MS metabolomics data

False discovery rate (FDR) control is an important tool of statistical inference in feature selection. In mass spectrometry-based metabolomics data, features can be measured at different levels of reliability and false features are often detected in untargeted metabolite profiling as chemical and/or bioinformatics noise. The traditional false discovery rate methods treat all features equally, which can cause substantial loss of statistical power to detect differentially expressed features. We propose a reliability index for mass spectrometry-based metabolomics data with repeated measurements, which is quantified using a composite measure. We then present a new method to estimate the local false discovery rate (lfdr) that incorporates feature reliability. In simulations, our proposed method achieved better balance between sensitivity and controlling false discovery, as compared to traditional lfdr estimation. We applied our method to a real metabolomics dataset and were able to detect more differentially expressed metabolites that were biologically meaningful.

Lipidomics to Assess Omega 3 Bioactivity

How can we resolve the conflict between the strong epidemiological evidence pointing to the usefulness of fish—and, thus, omega 3—consumption with the debacle of supplementation trials? One potential explanation is that the null results obtained thus far are the consequences of ill-contrived investigations that do not allow us to conclude on the effects (or lack thereof) of omega 3 fatty acid supplementation. One potential solution is through the use of lipidomics, which should prove very useful to screen suitable patients and to correlate plasma (or red blood cells, or whole blood, or phospholipid) fatty acid profile with outcomes. This has never been done in omega 3 trials. The wise use of lipidomics should be essential part of future omega 3 trials and would help in untangling this current riddle.

Milk, dairy products, and their functional effects in humans: a narrative review of recent evidence

Milk is a widely consumed beverage that is essential to the diet of several millions of people worldwide because it provides important macro- and micronutrients. Milk is recognized as being useful during childhood and adolescence because of its composition; however, its relatively high saturated fat proportion raises issues of potential detrimental effects, namely on the cardiovascular system. This review evaluates the most recent literature on dairy and human health, framed within epidemiologic, experimental, and biochemical evidence. As an example, the effects of milk (notably skimmed milk) on body weight appear to be well documented, and the conclusions of the vast majority of published studies indicate that dairy consumption does not increase cardiovascular risk or the incidence of some cancers. Even though the available evidence is not conclusive, some studies suggest that milk and its derivatives might actually be beneficial to some population segments. Although future studies will help elucidate the role of milk and dairy products in human health, their use within a balanced diet should be considered in the absence of clear contraindications.

Nutritional properties of dietary omega-3-enriched phospholipids

Dietary fatty acids regulate several physiological functions. However, to exert their properties, they have to be present in the diet in an optimal balance. Particular attention has been focused on tissue highly polyunsaturated fatty acids (HPUFAs) n-6/n-3 ratio, influenced by the type and the esterified form of dietary fatty acids. Dietary EPA and DHA when esterified to phospholipids (PLs) are more efficiently incorporated into tissue PLs and seem to possess peculiar properties through specific mechanism(s) of action, such as the capacity to affect endocannabinoid biosynthesis at much lower doses than EPA and DHA in triglyceride form, probably because of the above mentioned higher incorporation into tissue PLs. Downregulation of the endocannabinoid system seems to mediate the positive effects exerted by omega-3-enriched PLs on several parameters of metabolic syndrome. PLs are one of the major dietary forms of EPA and DHA we are exposed to with the everyday diet; therefore, it is not surprising that it guarantees an effective EPA and DHA nutritional activity. Future studies should address whether EPA and DHA in PL form are also more effective than other formulations in ameliorating other pathological conditions where n-3 HPUFAs seem to exert beneficial activities such as cancer and psychiatric disorders.

Dietary sources of omega 3 fatty acids: public health risks and benefits

Omega 3 fatty acids can be obtained from several sources, and should be added to the daily diet to enjoy a good health and to prevent many diseases. Worldwide, general population use omega-3 fatty acid supplements and enriched foods to get and maintain adequate amounts of these fatty acids. The aim of this paper was to review main scientific evidence regarding the public health risks and benefits of the dietary sources of omega-3 fatty acids. A systematic literature search was performed, and one hundred and forty-five articles were included in the results for their methodological quality. The literature described benefits and risks of algal, fish oil, plant, enriched dairy products, animal-derived food, krill oil, and seal oil omega-3 fatty acids.

Associations of very high intakes of eicosapentaenoic and docosahexaenoic acids with biomarkers of chronic disease risk among Yup'ik Eskimos

BACKGROUND

Few studies have examined the associations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) with biomarkers of chronic disease risk in populations with high intakes.

OBJECTIVE

We examined the associations of red blood cell (RBC) EPA and DHA, as percentages of total fatty acids, with biomarkers of chronic disease risk across a wide range of EPA and DHA intakes.

DESIGN

In a cross-sectional study of 357 Yup'ik Eskimos, generalized additive models were used to plot covariate-adjusted associations of EPA and DHA with chronic disease biomarkers. Linear regression models were used to test for the statistical significance of these associations.

RESULTS

Means (5th-95th percentiles) for RBC EPA and DHA were 2.8% (0.5-5.9%) and 6.8% (3.3-9.0%), respectively. Associations of EPA and DHA were inverse and linear for triglycerides (beta +/- SE = -0.10 +/- 0.01 and -0.05 +/- 0.01, respectively) and positive and linear for HDL cholesterol (beta +/- SE = 2.0 +/- 0.5 and 0.9 +/- 0.6, respectively) and apolipoprotein A-I (beta +/- SE = 2.6 +/- 0.8 and 1.7 +/- 0.8, respectively). Positive linear associations of DHA with LDL and total cholesterol (beta +/- SE = 7.5 +/- 1.4 and 6.80 +/- 1.57, respectively) were observed; for EPA, these associations were nonlinear and restricted to concentrations approximately <5% of total fatty acids. Associations of EPA and DHA with C-reactive protein were inverse and nonlinear: for EPA, the association appeared stronger at concentrations approximately >3% of total fatty acids; for DHA, it was observed only at concentrations approximately >7% of total fatty acids.

CONCLUSION

Increasing EPA and DHA intakes to amounts well above those consumed by the general US population may have strong beneficial effects on chronic disease risk.

Functional foods for dyslipidaemia and cardiovascular risk prevention

A food can be regarded as ‘functional’ if it can demonstrate a beneficial efficacy on one or more target functions in the body in a convincing way. Beyond adequate nutritional qualities, functional foods should either improve the state of health and wellbeing and/or reduce the risk of disease. Functional foods that are marketed with claims of heart disease reduction focus primarily on the major risk factors, i.e. cholesterol, diabetes and hypertension. Some of the most innovative products are designed to be enriched with ‘protective’ ingredients, believed to reduce risk. They may contain, for example, soluble fibre (from oat and psyllium), useful both for lowering cholesterol and blood pressure, or fructans, effective in diabetes. Phytosterols and stanols lower LDL-cholesterol in a dose-dependent manner. Soya protein is more hypocholesterolaemic in subjects with very high initial cholesterol and recent data indicate also favourable activities in the metabolic syndrome.n-3 Fatty acids appear to exert significant hypotriacylglycerolaemic effects, possibly partly responsible for their preventive activity. Dark chocolate is gaining much attention for its multifunctional activities, useful both for the prevention of dyslipidaemia as well as hypertension. Finally, consensus opinions about tea and coffee have not emerged yet, and the benefits of vitamin E, garlic, fenugreek and policosanols in the management of dyslipidaemia and prevention of arterial disease are still controversial.

Polyunsaturated fatty acids and cardiovascular disease

Replacing saturated with polyunsaturated (PUFAs) rather than monounsaturated fatty acids or carbohydrates results in cardiovascular prevention over a wide range of intakes. The mechanisms by which PUFAs reduce cardiovascular risk are manifold, and the extent and precise nature of their activities is the subject of several investigations, spanning from in vitro mechanistic studies to human intervention trials. This article reviews the most up-to-date evidence of the association between PUFA consumption and reduced cardiovascular mortality.

Milk enriched with "healthy fatty acids" improves cardiovascular risk markers and nutritional status in human volunteers

OBJECTIVE

The main goal of the present study was to evaluate the effect of a commercially available milk containing small amounts of eicosapentaenoic acid and docosahexaenoic acid, oleic acid, and vitamins A, B6, D, E, and folic acid compared with semi-skimmed and skimmed milk in volunteers with moderate cardiovascular risk.

METHODS

Two hundred ninety-seven subjects 25 to 65 y of age with moderate cardiovascular risk were randomly allocated into three groups. In addition to their diets, one group consumed 500 mL/d of the enriched milk, another group consumed 500 mL/d of skimmed milk, and a control group consumed 500 mL/d of semi-skimmed milk. All groups consumed the dairy drinks for 1 y and blood samples were taken at 0 and 12 mo.

RESULTS

Consumption of enriched milk for 1 y produced significant (P < 0.05) increases in serum folate (58%) and high-density lipoprotein cholesterol (4%). Plasma triacylglycerols (10%), total cholesterol (4%), and low-density lipoprotein cholesterol (6%) were reduced significantly only in the supplemented group. Serum glucose, homocysteine, and C-reactive protein remained unchanged. In the skimmed milk and semi-skimmed milk groups, the only significant decreases were in serum folate (17% and 11%, respectively).

CONCLUSION

Daily intake of a milk enriched with fish oil, oleic acid, and vitamins improved the nutritional status and cardiovascular risk markers of volunteers, whereas skimmed milk and semi-skimmed milk did not.

Regular consumption ofn-3 fatty acid-enriched pork modifies cardiovascular risk factors

The long-chain (LC)n-3 PUFA content of pork, particularly DHA, can be increased by including 15 % PorcOmega®(a fortified tuna fishmeal product) in pig finisher diets. The aim of the present study was to see whether this enriched pork could deliver cardiovascular health benefits to consumers. In a double-blind intervention trial, thirty-three healthy adult volunteers (sixteen female and seventeen male) were randomised to consume eithern-3-enriched or regular (control) pork (a selection of five fresh cuts totalling 1000 g/week) for 12 weeks. Fasting blood samples were collected every 4 weeks and analysed for serum lipids, maximally stimulated thromboxane production and erythrocyte fatty acid composition. Then-3-enriched pork provided subjects with 1·3 g LCn-3 PUFA per week. Erythrocyte DHA levels rose 15 % in then-3 group and fell 5 % in the control group over 12 weeks (P = 0·001). Compared with the control group, serum TAG decreased to a greater extent in then-3 group (P = 0·02) and serum thromboxane production increased to a lesser extent (P = 0·004). Changes in the latter were inversely associated with changes in incorporation of DHA into erythrocytes (r − 0·54;P < 0·05). Thus the modest increases in LCn-3 PUFA intake resulting from regular consumption of enriched pork can improve cardiovascular risk factors.

Dietary macronutrient intake and five-year incident cataract: the blue mountains eye study

PURPOSE

To investigate the relationships between dietary macronutrient intake at baseline and the five-year incidence of the three main types of cataract in older people.

DESIGN

Population-based cohort study.

METHODS

SETTINGS

An urban community near Sydney, Australia.

STUDY POPULATION

The Blue Mountains Eye Study (BMES) examined 3,654 predominantly Caucasian participants aged 49+ years during 1992 to 1994, and then 2,335 survivors (71.5%) after five years. Of these 2,335 subjects, 1988 (85%) completed a Willett-derived food frequency questionnaire (FFQ) at baseline.

OBSERVATION PROCEDURES

A 145-item FFQ was used to assess nutrient intakes and lens photography was used to assess the presence of cataract at both time points.

MAIN OUTCOME MEASURES

Incidence of cortical, nuclear, and posterior subcapsular (PSC) cataract was assessed via lens photographic grading following the Wisconsin cataract grading method.

RESULTS

After adjusting for multiple known cataract risk factors, higher dietary intakes of omega-3 polyunsaturated fatty acids (n-3 PUFA) were associated with a reduced incidence of nuclear cataract. The odds ratio (OR) for subjects in the highest quintile of intake compared to those in the lowest quintile was 0.58 (95% confidence interval [CI] 0.35 to 0.97), P(trend) = .027. Similarly, for PSC cataract, higher dietary intakes of protein were protective (OR 0.28; 95% CI 0.10 to 0.76), P(trend) = .015. Dietary macronutrient intake was not associated with incident cortical cataract.

CONCLUSIONS

Higher dietary intakes of n-3 PUFA may decrease the five-year risk of nuclear cataract, whereas higher dietary intakes of protein may decrease risk for PSC cataract.

Impact of foods enriched withn-3 long-chain polyunsaturated fatty acids on erythrocyten-3 levels and cardiovascular risk factors

Consumption of fish or fish oils rich in then-3 long chain PUFA EPA and DHA may improve multiple risk factors for CVD. The objective of this study was to determine whether regular consumption of foods enriched withn-3 long-chain PUFA can improven-3 long-chain PUFA status (erythrocytes) and cardiovascular health. Overweight volunteers with high levels of triacylglycerols (TG; >1·6 mmol/l) were enrolled in a 6-month dietary intervention trial conducted in Adelaide (n47) and Perth (n39), and randomised to consume control foods orn-3-enriched foods to achieve an EPA + DHA intake of 1 g/d. Test foods were substituted for equivalent foods in their regular diet. Erythrocyte fatty acids, plasma TG and other CVD risk factors were monitored at 0, 3 and 6 months. There were no significant differences between groups for blood pressure, arterial compliance, glucose, insulin, lipids, C-reactive protein (CRP) or urinary 11-dehydro-thromboxane B2(TXB2) over 6 months, even though regular consumption ofn-3-enriched foods increased EPA + DHA intake from 0·2 to 1·0 g/d. However, then-3 long-chain PUFA content of erythrocytes increased by 35 and 53 % at 3 and 6 months, respectively, in subjects consuming then-3-enriched foods. These increases were positively associated with measures of arterial compliance and negatively associated with serum CRP and urinary 11-dehydro-TXB2excretion. Sustainable increases in dietary intakes and erythrocyte levels ofn-3 long-chain PUFA can be achieved through regular consumption of suitably enriched processed foods. Such increases may be associated with reduced CV risk.

Milk and the metabolic syndrome

The metabolic syndrome is a cluster of metabolic disorders, namely dyslipidaemia, hypertension, obesity and glucose intolerance. Insulin resistance is the core phenomenon. Co-occurrence is associated with increased cardiovascular disease (CVD) risk. Observational studies found no increased CVD risk with increasing consumption of milk and other dairy products. In several studies dairy consumption was inversely associated with the occurrence of one or several facets of the metabolic syndrome. Many dairy components may contribute to the beneficial effects. Milk and particularly whey appeared insulinotropic when given in a single meal, but not in longer-term intervention. Medium chain fatty acids improve insulin sensitivity. Whey proteins, amino acids, medium chain fatty acids and in particular calcium and other minerals may contribute to the beneficial effect of dairy products on body weight and body fat. Peptides, calcium and other minerals reduce blood pressure. Fermented products and probiotic bacteria decrease absorption of cholesterol, sphingomyelin of cholesterol and fat, calcium of cholesterol, bile acids and fat. Proteins, peptides and bacteria may also reduce plasma cholesterol. Lactose, citrate, proteins and peptides improve weight control, blood pressure and plasma lipids indirectly, by improving calcium bioavailability. Furthermore, dairy consumption improves the bioavailability of folate and other secondary plant components.

Intake of fish oil, oleic acid, folic acid, and vitamins B-6 and E for 1 year decreases plasma C-reactive protein and reduces coronary heart disease risk factors in male patients in a cardiac rehabilitation program

Certain nutrients have been shown to be effective in preventing coronary heart disease. We hypothesized that a daily intake of low amounts of a number of these nutrients would exert beneficial effects on risk factors and clinical variables in patients that suffered from myocardial infarction (MI) and were following a cardiac rehabilitation program. Forty male MI patients were randomly allocated into 2 groups. The supplemented group consumed 500 mL/d of a fortified dairy product containing eicosapentaenoic acid, docosahexaenoic acid, oleic acid, folic acid, and vitamins A, B-6, D, and E. The control group consumed 500 mL/d of semi-skimmed milk with added vitamins A and D. The patients received supervised exercise training, lifestyle and dietary recommendations, and they were instructed to consume the products in addition to their regular diet. Blood extractions and clinical examinations were performed after 0, 3, 6, 9, and 12 mo. Plasma concentrations of eicosapentaenoic acid, docosahexaenoic acid, oleic acid, folic acid, vitamin B-6, and vitamin E increased after supplementation (P<0.05). Plasma total and LDL-cholesterol, apolipoprotein B, and high-sensitivity C-reactive protein concentrations decreased in the supplemented group (P<0.05), and plasma total homocysteine decreased in both groups. There were no changes in heart rate, blood pressure, or cardiac electrocardiographic parameters in either group. Therapeutic lifestyle changes, effected through a CR program comprising regular exercise and the intake of a combination of dietary nutrients, reduced a variety of risk factors in MI patients, which supports the rationale for nutritional programs in the secondary prevention of coronary heart disease.

Endogenous production and elevated levels of long-chain n-3 fatty acids in the milk of transgenic mice

N-3 Polyunsaturated fatty acids (n-3 PUFA) are important for the normal development and functioning of all organisms. Mammals lack the n-3 fatty acid desaturase required for the synthesis of alpha-linolenic acid (18:3n-3), and are therefore dependent on dietary sources to obtain this essential fatty acid. Currently, the richest source of dietary long-chain n-3 PUFA, eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3), are triacylglycerides extracted from rapidly declining marine resources. The nematode Caenorhabditis elegans synthesizes a wide range of PUFA and possesses the only known example of an n-3 fatty acid desaturase enzyme in the animal kingdom. Transgenic mice expressing the C. elegans n-3 desaturase under the control of the lactation-induced goat beta-casein mammary gland promoter were generated via pronuclear microinjection. Significant increases in n-3 PUFA, decreases in n-6 PUFA, and an overall decrease in the n-6:n-3 PUFA ratio were observed in the milk produced by transgenic mice. Neonate mice consuming milk from transgenic females accumulated increased levels of docosahexaenoic acid in their brains. This transgenic model may provide useful information to address some basic questions of neonatal nutrition, and demonstrates one of the steps that would be required to increase the n-3 PUFA content of milk and dairy products endogenously. Increasing the proportion of n-3 PUFA in milk fat would help to improve the nutritional composition of an important component of the North American diet.

Daily supplementation with (n-3) PUFAs, oleic acid, folic acid, and vitamins B-6 and E increases pain-free walking distance and improves risk factors in men with peripheral vascular disease

A number of nutrients are known to be effective in preventing cardiovascular disease (CVD). We investigated the possible effects of a daily intake of low amounts of these nutrients on risk factors and clinical parameters in patients with peripheral vascular disease and intermittent claudication (PVD-IC). Male PVD-IC patients (n = 60) were randomly allocated into 2 groups. The supplement (S) group consumed 500 mL/d of a fortified dairy product containing eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), oleic acid, folic acid, and vitamins A, B-6, D, and E. The control (C) group consumed 500 mL/d of semiskimmed milk with added vitamins A and D. The patients received lifestyle and dietary recommendations, and they were instructed to consume the products in addition to their regular diet. Blood extractions and clinical explorations were performed after 0, 3, 6, 9, and 12 mo. Plasma concentrations of EPA, DHA, oleic acid, folic acid, and vitamins B-6 and E increased after treatment with supplements (P < 0.05). Plasma total cholesterol and ApoB concentrations decreased in the S group, and total homocysteine decreased in those patients with high initial concentrations. Walking distance before the onset of claudication increased in the S group (P < 0.001), and ankle-brachial pressure index values increased (P < 0.05). The inclusion in the everyday diet of certain nutrients known to promote cardiovascular health improved clinical outcomes while reducing a variety of risk factors in men with PVD-IC, providing new evidence of the potential role of nutrition in the reduction of PVD-IC symptoms.

Hot Topic: Endogenous Production of n-3 and n-6 Fatty Acids in Mammalian Cells

Polyunsaturated fatty acids (PUFA) are important components of mammalian diets, and the beneficial effects of n-3 PUFA on human development and cardiovascular health have been well documented. Caenorhabditis elegans is one of the few animals known to be able to produce linoleic (LA, 18:2n-6) and alpha-linolenic (ALA, 18:3n-3) essential fatty acids. These essential PUFA are generated by the action of desaturases that successively direct the conversion of monounsaturated fatty acids (MUFA) to PUFA. The cDNA coding sequences of the C. elegans Delta(12) and n-3 fatty acid desaturases were each placed under the control of separate constitutive eukaryotic promoters and simultaneously introduced into HC11 mouse mammary epithelial cells by adenoviral transduction. Phospholipids from transduced cells showed a significant decrease in the ratios of both MUFA:PUFA and n-6:n-3 fatty acids relative to control cultures. The fatty acid profile of transduced cellular phospholipids revealed significant decreases in MUFA and arachidonic acid (20:4n-6), and increases in LA, ALA, and eicosapentaenoic acid (20:5n-3). The fatty acid composition of triacylglycerols derived from transduced cells was similarly, but less dramatically, affected. These results demonstrate the functionality of C. elegans fatty acid desaturase enzymes in mammalian cells. Expression of these desaturases in livestock might act to counterbalance the saturating effect that rumen microbial biohydrogenation has on the fatty acid profile of ruminant products, and allow for the development of novel, land-based dietary sources of n-3 PUFA.

Cardiovascular effects of milk enriched with ω-3 polyunsaturated fatty acids, oleic acid, folic acid, and vitamins E and B6 in volunteers with mild hyperlipidemia

OBJECTIVE

Results from epidemiologic studies and clinical trials have indicated that consumption of omega-3 fatty acids, oleic acid, and folic acid have beneficial effects on health, including decreased risk of cardiovascular disease. We evaluated the combined effects of these nutrients through the consumption of milk enriched with omega-3 polyunsaturated fatty acids, oleic acid, vitamins E and B6, and folic acid on risk factors for cardiovascular disease in volunteers with mild hyperlipidemia.

METHODS

Thirty subjects ages 45 to 65 y (51.3 +/- 5.3 y) were given 500 mL/d of semi-skimmed milk for 4 wk and then 500 mL/d of the enriched milk for 8 wk. Plasma and low-density lipoproteins were obtained at the beginning of the study and at 4, 8, and 12 wk.

RESULTS

Consumption of enriched milk for 8 wk increased plasma concentrations of docosahexaenoic acid and eicosapentaenoic acid and significantly (P < 0.05) decreased plasma concentrations of triacylglycerol (24%), total cholesterol (9%), and low-density lipoprotein cholesterol (13%). Plasma and low-density lipoprotein oxidation and vitamin E concentration remained unchanged throughout the study. Significant decreases in plasma concentrations of vascular cell adhesion molecule-1 (9%) and homocysteine (17%) were found, accompanied by a 98% increase in plasma concentration of folic acid.

CONCLUSIONS

Dairy supplementation strategies with omega-3 polyunsaturated fatty acids, oleic acid, and vitamins may be useful for decreasing risk factors for cardiovascular disease.

A practical approach to increasing intakes of n-3 polyunsaturated fatty acids: use of novel foods enriched with n-3 fats

OBJECTIVES

To assess the effects of providing a wide range of foodstuffs containing n-3 polyunsaturated fatty acids (PUFA), occurring naturally or from fortification, on intake and blood and tissue proportions of n-3 PUFA.

DESIGN

Before/after dietary intervention study.

SETTING

Adelaide, Australia.

SUBJECTS

16 healthy males recruited from the community.

INTERVENTIONS

Subjects were provided with a range of foodstuffs naturally containing n-3 PUFA (fresh fish, canned fish, flaxseed meal, canola oil) and items fortified with fish oil (margarine spread, milk, sausages, luncheon meat, french onion dip). Food choices were left to the discretion of each subject. Intake was estimated by diet diary. Blood was collected at-2, 0, 2, and 4 weeks for fatty acid analysis.

MAIN OUTCOME MEASURES

Dietary intakes; plasma, platelet, and mononuclear cell phospholipid fatty acids.

RESULTS

Consumption of n-3 PUFA increased significantly: alpha-linolenic acid (ALA) from 1.4 to 4.1 g/day (P<0.001), eicosapentaenoic acid (EPA) from 0.03 to 0.51 g/day (P<0.001), and docosahexaenoic acid (DHA) from 0.09 to 1.01 g/day (P<0.001). Linoleic acid (LA) intake decreased from 13.1 to 9.2 g/day (P<0.001). The proportions of EPA and DHA increased significantly in all phospholipid pools examined; plasma EPA from 1.13% of total fatty acids to 3.38% (P<0.001) and DHA from 3.76 to 7.23% (P<0.001); mononuclear cell EPA from 0.40 to 1.25% (P<0.001) and DHA from 2.33 to 4.08% (P<0.001); platelet EPA from 0.41 to 1.2% (P<0.001) and DHA from 1.64 to 3.07% (P<0.001).

CONCLUSION

Incorporating fish oil into a range of novel commercial foods provides the opportunity for wider public consumption of n-3 PUFA with their associated health benefits.

SPONSORSHIP

Dawes Scholarship, Royal Adelaide Hospital.

Hydroxytyrosol excretion differs between rats and humans and depends on the vehicle of administration

Interest in the in vivo biological activities of olive oil phenolics is rapidly growing, and different models and vehicles of administration are used worldwide. Matters of practicality determine the use of rats rather than humans as the model of choice. Also, growing interest in nutraceuticals is leading to the formulation of compounds containing olive oil phenols. In this study, we compared metabolism and urinary excretion of hydroxytyrosol [(HT), the most representative phenol of olive oil] between rats and humans by evaluating excretion of HT and its major metabolite, homovanillyl alcohol. Also, we compared human excretion of HT when consumed as a natural component of extra virgin olive oil, when added to refined olive oil, or when added to yogurt (as an approximation of functional food). Urinary excretion of HT was greater in humans than in rats, a species with a high basal excretion of HT and its metabolites. The high (234% of HT administered) excretion of free HT suggests that hydrolysis of oleuropein administered in humans (still an unresolved issue) occurs in vivo. Moreover, human HT excretion was much higher after its administration as a natural component of olive oil (44.2% of HT administered) than after its addition to refined olive oil (23% of HT administered) or yogurt (5.8% of dose or approximately 13% of that recorded after virgin olive oil intake). These data suggest that the rat is not the appropriate model for the study of HT metabolism and that HT-containing functional foods should be carefully formulated.

Bread enriched with microencapsulated tuna oil increases plasma docosahexaenoic acid and total omega-3 fatty acids in humans

The aim of this study was to determine the acute and chronic effects of low doses of long chain (LC) n-3 polyunsaturated fatty acids (PUFA) (<100 mg per day) on plasma LC n-3 PUFA levels using a novel delivery form; bread containing microencapsulated tuna oil (MTO). Six omnivores (three men and three women) participated in the acute study, which involved ingesting a prototype MTO bread containing approximately 80 mg of LC n-3 PUFA/four slices. Plasma triacylglycerol fatty acid compositions were measured after an overnight fast and postprandially at 2 and 4 h. In the chronic study, 10 vegetarian subjects (nine men and one woman) consumed MTO bread at six to eight slices/day (comprising 60 mg of LC n-3 PUFA) as the only dietary source of these PUFA for three weeks. Fasting plasma total and phospholipid fatty acid compositions were measured at baseline and endpoint. In the acute study, the proportions of 22:6 n-3 and total n-3 PUFA in plasma triacylglycerol were significantly increased (P < 0.05). In the chronic study, the proportions of 20:5 n-3, 22:5 n-3, 22:6 n-3, total n-3 PUFA in plasma, and 22:6 n-3 and total n-3 PUFA in plasma phospholipid fractions were significantly increased (P < 0.05) at the endpoint compared with the baseline. This study showed that a low dose of LC n-3 PUFA, consumed as MTO-enriched bread, was bioavailable, as measured by an increase in LC n-3 PUFA levels in the plasma of human subjects.

The composition of bovine milk lipids: January 1995 to December 2000

Data from recent publications on bovine milk lipids are presented and discussed. This includes extraction of lipids, triacylglycerols, phospholipids, other complex lipids, sterols, isoflavones, and fatty acids. Improved gas-liquid and high performance liquid chromatography were used. Data on the trans and cis isomers of fatty acid and of conjugated linoleic acids are given, and the analyses are described. Papers about the lipids in milks and dairy products from the United States are few; where with the exception of trans-fatty acid isomers and conjugated linoleic acids, almost no research has been reported.