Dietary supplementation of obese children with 1000 mg alpha-linolenic acid per day: a placebo-controlled double blind study

INTRODUCTION: Enhanced dietary intake of omega-3 fatty acids may benefit persons with increased cardiovascular risk, among them obese subjects. Incorporation of omega-3 fatty acids into the plasma lipids is a prerequisite to achieve the favorable effects; however, only very few data are available on the dose of omega-3 fatty acid supplementation in children. The aim of our study was to examine the effects of the consumption of a diet supplemented with 1000 mg alpha-linolenic acid daily on plasma lipids in obese children. METHODS: In this two times six-week-long, placebo-controlled, crossover study, 9 obese children (age: 13.1 [2.5] years, body mass index: 31.2 [6.2] kg/m 2 ), median [IQR]) incorporated into their diet one egg and one meatball (50 g) per day from hens fed diets containing flaxseed oil, i.e. supplementary dietary intake of 1000 mg alpha-linolenic acid per day was provided. The fatty acid composition of plasma lipids was determined by high-resolution gas-liquid chromatography. RESULTS: Tendencies of increase were observed in the alpha-linolenic acid content of plasma lipids in the phospholipid, triacyl-glycerine and sterol-ester fractions after the supplementation with alpha-linolenic acid. In the non-esterified fatty acid fraction, the values of alpha-linolenic acid were significantly higher after the supplementation (0.11 [0.08] versus 0.14 [0.20], % weight/weight, p < 0.05), indicating the beginning of the accumulation of alpha-linolenic acid in plasma lipids. CONCLUSION: In obese children a six-week-long supplementation of the diet with 1000 mg alpha-linolenic acid per day increased significantly the contribution of omega-3 fatty acids only to the non-esterified fatty acids of plasma lipids, but had no significant effect on the esterified fractions. Increase of the dose of supplementation may be needed to influence omega-3 fatty acid status in obese children.     

Intervention with flaxseed and borage oil supplements modulates skin condition in women

Ingestion of selected nutrients modulates dermal properties. In the present study, two groups of women ingested flaxseed or borage oil for 12 weeks. The control group received a placebo containing medium-chain fatty acids. Dose was 2.2 g total fatty acids/d with alpha-linolenic acid and linoleic acid as major constituents in the flaxseed oil group; in the borage oil group linoleic and gamma-linolenic acid were predominant. In the flaxseed oil group, the contribution of alpha-linolenic acid to total fatty acids in plasma was significantly increased on weeks 6 and 12, whereas there was an increase in gamma-linolenic acid in the borage oil group (P < 0.05). Skin irritation was performed by nicotinate treatment, and changes in skin reddening and blood flow were monitored. Compared to week 0, skin reddening was diminished in both groups; blood flow was also lowered. Skin hydration was significantly increased after 12 weeks of treatment compared to week 0, with flaxseed or borage oil (P < 0.05). Transepidermal water loss was decreased in both oil groups by about 10 % after 6 weeks of supplementation. A further decrease was determined after 12 weeks in the flaxseed oil group. Surface evaluation of living skin revealed that roughness and scaling of the skin were significantly decreased with flaxseed and borage oil comparing week 0 and week 12 (P < 0.05). Except for hydration, none of the parameters was affected in the placebo group. The present data provide evidence that skin properties can be modulated by an intervention with dietary lipids.     

Effect of Flaxseed (Linum usitatissimum L.) Supplementation on Vascular Endothelial Cell Morphology and Function in Patients with Dyslipidaemia—A Preliminary Observation

Context: Flaxseed has a characteristic fatty acids composition and unique phytonutrient profile that may have health-promoting properties. Objective: This study aimed to determine the effects of 10 weeks of supplementation with the flaxseed (28 g/day) on endothelial cells (EC) function, serum lipids and proinflammatory mediators in patients with mild and severe dyslipidaemia. Materials and methods: Eleven lean patients with severe dyslipidaemia treated with apheresis (group 1; 10 weeks treated in four phases: (i) ordinary diet, (ii) ordinary diet + flaxseed, (iii) ordinary diet (wash out), (iv) ordinary diet + placebo) and eleven obese patients with mild dyslipidaemia—not treated with apheresis (group 2; 10 weeks treated in two phases: (i) ordinary diet, (ii) low fat diet + flaxseed). Flaxseed was given blindly. Serum was collected at the end of each phase of the study. ECs were exposed in vitro to the medium supplemented with pooled serum taken from patients from both groups to detect their morphological changes using light and electron microscopy. ECs proliferation was also measured at the end of each study phase. Results: Serum vascular endothelial growth factor was decreased after flaxseed supplementation but only in group 1. ECs proliferation was increased after flaxseed supplementation only in obese patients. ECs exposed to medium supplemented with obese patients’ serum revealed the following cellular abnormalities: accumulation of lipid droplets, changes of rough endoplasmic reticulum and mitochondria, and flaxseed did not reverse observed changes. At the same time, flaxseed supplementation decreases total cholesterol in both tested groups, low-density lipoprotein cholesterol in group 1 and triglycerides in group 2. Conclusions: Our findings support the potential role of flaxseed in treating dyslipidaemia but indicate only a slight impact on endothelial cell function.     

The effect of dietary trans alpha-linolenic acid on plasma lipids and platelet fatty acid composition: the TransLinE study

OBJECTIVE: To collect (i) baseline data and (ii) execute a large multicentre study examining the effect of trans alpha-linolenic acid on its incorporation into plasma lipids and on risk factors for coronary heart disease. DESIGN: Male volunteers were recruited and the habitual diet assessed by a 4-d weighed record. Fatty acid composition of plasma and platelet lipids were determined by gas chromatography at baseline. After a 6 week run-in period on a trans 'free' diet, male volunteers were randomised to consume 0.6 % of energy trans alpha-linolenic acid or to continue with a diet 'low' in trans alpha-linolenic acid for 6 weeks. SETTING: Three European university research departments supported by the research and development departments of the food industry. Subjects: Male volunteers (88) recruited by local advertisement. METHODS: Replacement of 30 % of the fat of the habitual diet by margarine, oil and foods. Rapeseed oil was deodorised especially to produce the trans 'free' and 'high' trans foods for this study. The incorporation and conversion of trans alpha-linolenic acid into plasma lipids and platelets was assessed by gas chromatography and dietary compliance was verified by 4-d weighed record. Results: Less trans alpha-linolenic acid isomers are incorporated into human plasma lipids in French volunteers than in Dutch or Scottish volunteers consuming their habitual diets. Trans 'free' alpha-linolenic acid-rich oil can be produced by careful deodorization during refining. The 'high' trans diet provided 1410+/-42 mg/d trans isomers of alpha-linolenic acid, whilst the 'low' trans group consumed 60+/-75 mg/d. The change in plasma lipid and platelet fatty acid composition documented that trans linolenic isomers are incorporated and converted to a trans isomer of eicosapentaenoic acid. Only the 15-trans alpha-linolenic acid is incorporated into plasma cholesteryl esters. The group consuming low trans diet had a slightly higher intake of fat, especially saturated and monounsaturated fat. CONCLUSIONS: Trans 'free' rapeseed oil, rich in alpha-linolenic acid, can be produced by careful deodorization. Dietary records show good compliance. Dietary trans isomers of alpha-linolenic acid are incorporated in plasma lipids and converted to long-chain polyunsaturated fatty acids. Their effects on risk factors for coronary heart disease and their metabolism will be reported elsewhere. Sponsorship: European Commission (FAIR 95-0594 grant). European Journal of Clinical Nutrition (2000) 54, 104-113     

Dietary fat modulates serum paraoxonase 1 activity in rats

We examined the effects of dietary fats with specific fatty acid compositions, on serum paraoxonase (PON1) activity in rats. Male adult Sprague-Dawley rats were divided randomly into four dietary groups. One group received the control diet [AIN 93M with soybean oil (5 g/100 g diet)], whereas the remaining three groups received the modified control diet supplemented with (15 g/100 g diet) triolein, tripalmitin or fish oil, respectively. After 20 d, blood was obtained after overnight food deprivation and PON1 activity was determined. Serum lipids and lipid components of lipoproteins were also determined. Serum PON1 activity [micromol/(L.min)] was significantly (P: < 0.05) higher in triolein (98 +/- 6) and lower in fish oil (41 +/- 4), compared with tripalmitin-fed rats (63 +/- 11). Serum PON1 activity in tripalmitin-fed rats was comparable to that of controls (67 +/- 9). Serum PON1 activity correlated significantly with serum lecithin:cholesterol acyltransferase (LCAT) activity (r = 0.77, P: < 0.001) and was transported in blood principally in association with the denser subfraction of HDL, very high density lipoprotein (VHDL; d > 1.15 kg/L). Serum PON1 activity correlated strongly with serum lipids as well as lipids of VLDL, HDL and its subfractions. Multiple linear regression analysis, however, showed a significant relationship of serum PON1 activity, principally with the phospholipids of VHDL (r = 0.47, P: < 0.002). These data suggest that the modulation of serum PON1 activity by dietary fat may be mediated via the effect of the specific fatty acids on the synthesis and secretion of VHDL, the subfraction of HDL that transports the majority of PON1 in the blood.     

Biochemical effects of a diet containing foods enriched with n-3 fatty acids

BACKGROUND: Results of many studies indicate that consumption of n-3 fatty acids can benefit persons with cardiovascular disease and rheumatoid arthritis. However, encapsulated fish oil is unlikely to be suited to lifetime daily use and recommendations to increase fish intake have not been effective. OBJECTIVE: The objective was to examine the effectiveness of a diet that incorporates foods rich in n-3 fatty acids in elevating tissue concentrations of eicosapentaenoic acid and in suppressing the production of inflammatory mediators. DESIGN: Healthy male volunteers were provided with foods that were enriched in alpha-linolenic acid (cooking oil, margarine, salad dressing, and mayonnaise) and eicosapentaenoic and docosahexaenoic acids (sausages and savory dip) and with foods naturally rich in n-3 fatty acids, such as flaxseed meal and fish. Subjects incorporated these products into their food at home for 4 wk. Fatty acid intakes, cellular and plasma fatty acid concentrations, and monocyte-derived eicosanoid and cytokine production were measured. RESULTS: Analyses of dietary records indicated that intake of eicosapentaenoic acid plus docosahexaenoic acid averaged 1.8 g/d and intake of alpha-linolenic acid averaged 9. 0 g/d. These intakes led to an average 3-fold increase in eicosapentaenoic acid in plasma, platelet, and mononuclear cell phospholipids. Thromboxane B(2), prostaglandin E(2), and interleukin 1beta synthesis decreased by 36%, 26%, and 20% (P < 0.05), respectively. CONCLUSIONS: Foods that are strategically or naturally enriched in n-3 fatty acids can be used to achieve desired biochemical effects without the ingestion of supplements or a change in dietary habits. A wide range of n-3-enriched foods could be developed to support large-scale programs on the basis of the therapeutic and disease-preventive effects of n-3 fatty acids.     

Supplementing lactating women with flaxseed oil does not increase docosahexaenoic acid in their milk

BACKGROUND: Flaxseed oil is a rich source of 18:3n-3 (alpha-linolenic acid, or ALA), which is ultimately converted to 22:6n-3 (docosahexaenoic acid, or DHA), a fatty acid important for the development of the infant brain and retina. OBJECTIVE: The objective of this study was to determine the effect of flaxseed oil supplementation on the breast-milk, plasma, and erythrocyte contents of DHA and other n-3 fatty acids in lactating women. DESIGN: Seven women took 20 g flaxseed oil (10.7 g ALA) daily for 4 wk. Breast-milk and blood samples were collected weekly before, during, and after supplementation and were analyzed for fatty acid composition. RESULTS: Breast milk, plasma, and erythrocyte ALA increased significantly over time (P < 0.001) and after 2 and 4 wk of supplementation (P < 0.05). Over time, 20:5n-3 (eicosapentaenoic acid, or EPA) increased significantly in breast milk (P = 0.004) and in plasma (P < 0.001). In addition, plasma EPA increased significantly (P < 0.05) after 2 and 4 wk of supplementation. There were significant increases over time in breast-milk 22:5n-3 (docosapentaenoic acid, or DPA) (P < 0.02), plasma DPA (P < 0.001), and erythrocyte DPA (P < 0.01). No significant changes were observed in breast-milk, plasma, or erythrocyte DHA contents after flaxseed oil supplementation. CONCLUSIONS: Dietary flaxseed oil increased the breast-milk, plasma, and erythrocyte contents of the n-3 fatty acids ALA, EPA, and DPA but had no effect on breast-milk, plasma, or erythrocyte DHA contents.     

Effects of fatty and lean fish intake on blood pressure in subjects with coronary heart disease using multiple medications

BACKGROUND: Intake of fish and long-chain n-3 fatty acids has been of wide interest due to their beneficial effects on cardiovascular risk factors and lower coronary heart disease (CHD) risk. AIM OF THE STUDY: The aim of this pilot study was to examine the effects of fatty fish and lean (white) fish on fatty acid composition of serum lipids and cardiovascular risk factors in subjects with CHD using multiple drugs for this condition. METHODS: The study was an 8-week controlled, parallel intervention. Inclusion criteria were myocardial infarction or unstable ischemic attack, age under 70 years, use of betablockers and presence of sinus rhythm. The subjects were randomized to one of the following groups: 4 meals/week fatty fish (n = 11), 4 meals/week lean fish (n = 12) and control diet including lean meat (n = 10). RESULTS: The mean (+/-SD) of reported fish meals per week was 4.3 +/- 0.4, 4.7 +/- 1.1 and 0.6 +/- 0.4 in the groups, respectively. The proportions of eicosapentaenoic and docosahexaenoic acids in serum lipids increased in the fatty fish group only (P < 0.05). Systolic and diastolic blood pressure levels decreased in the lean fish group (0 vs. 8 week: 3.5 +/- 3.2 and 4.6 +/- 3.6%, respectively, P < 0.05). Serum total triglyceride concentration did not significantly change. HDL cholesterol concentration change differed among groups but without significant post hoc differences. Apolipoprotein A-1 concentration decreased in the control group (0 vs. 8 week, P < 0.05). Coagulation factors, 25-hydroxy vitamin D, and heart rate variability (24 h Holter) did not change among the groups. CONCLUSIONS: Our results suggest that intake of lean fish at least four times per week could reduce blood pressure levels in CHD patients.     

Evaluation of a food frequency questionnaire with weighed records, fatty acids, and alpha-tocopherol in adipose tissue and serum.

The authors examined the validity of a self-administered 180-item food frequency questionnaire in 125 Norwegian men aged 20-55 years who filled in the questionnaire and completed 14-day weighed records in fall 1995 to winter 1995/6. Spearman correlation coefficients between the two measurements ranged from 0.42 for percent of energy from fat to 0.66 for sugar intake (median r = 0.51). On average, 39% of the men were classified in the same quartile with the two methods, and 3% in the opposite quartile. Correlation coefficients between intake of fatty acids estimated from the questionnaire and the relative amounts of fatty acids in adipose tissue were: linoleic acid (18:2, n-6), r = 0.38; alpha-linolenic acid (18:3, n-3), r = 0.42; eicosapentaenoic acid (20:5, n-3), r = 0.52; and docosahexaenoic acid (22:6, n-3), r = 0.49. The correlations for these fatty acids between the total serum lipids and the diet were 0.16, 0.28, 0.51 and 0.52, respectively. The data suggest that very-long-chain n-3 fatty acids in adipose tissue and total serum lipids reflect the dietary intake of very-long-chain n-3 fatty acids to the same degree. No associations were observed between intake of alpha-tocopherol and concentration in adipose tissue and serum.     

Chemopreventive effects of dietary flaxseed oil on colon tumor development

Fatty acid composition of dietary fat, primarily the levels of omega-3 and omega-6 polyunsaturated fatty acids, has shown profound effect on colon tumor development in animal studies. Fats containing omega-6 fatty acids (for example, corn oil) enhanced and omega-3 fatty acids (for example, fish oil and mustard oil) reduced chemically induced colon tumors in rats. The purpose of this study was to investigate the effects of dietary flaxseed oil (containing alpha-linolenic acid, an omega-3 polyunsaturated fatty acid) on azoxymethane-induced colon tumor in rats and how it compared with the dietary corn oil-treated group. Male Fischer rats, separated into 2 groups of 30, were assigned to the AIN-93M diet, which was supplemented with either 15% corn oil or 15% flaxseed oil. Carcinogenesis was initiated with subcutaneous injections of azoxymethane (15 mg/kg) once a week for three consecutive weeks. Thirty-five weeks after initiation, the rats were sacrificed under ether anesthesia. Blood was collected by cardiac puncture. The gastrointestinal tract was isolated and flushed with ice-cold normal saline. The site, size, and number of tumors were recorded. The incidence and multiplicity of the tumors in the colon were determined. The fatty acid composition in the serum, colon, and tumors was estimated by using gas chromatography-flame ionization detection. Colon tumor incidence was found to be 100% and 54%, whereas multiplicity was found to be 3.1 and 0.7 tumors per rat in corn oil- and flaxseed oil-treated groups, respectively. Tumor size was significantly larger in the corn oil-treated group than in the flaxseed oil group. Colon and serum samples of the corn oil group showed an increase in the omega-6 fatty acid levels, whereas the flaxseed oil group exhibited an increase in the omega-3 fatty acid levels. The results indicate that dietary flaxseed oil, containing high levels of omega-3 fatty acids, is effective in preventing colon tumor development when compared with dietary corn oil containing omega-6 fatty acids in rats.     

Flaxseed and cardiovascular risk

Flaxseed has recently gained attention in the area of cardiovascular disease primarily because it is the richest known source of both alpha-linolenic acid (ALA) and the phytoestrogen, lignans, as well as being a good source of soluble fiber. Human studies have shown that flaxseed can modestly reduce serum total and low-density lipoprotein cholesterol concentrations, reduce postprandial glucose absorption, decrease some markers of inflammation, and raise serum levels of the omega-3 fatty acids, ALA and eicosapentaenoic acid. Data on the antiplatelet, antioxidant, and hypotensive effects of flaxseed, however, are inconclusive. More research is needed to define the role of this functional food in reducing cardiovascular risk.     

Time-course effects of protein malnutrition on hepatic fatty acids delta 6 and delta 5 desaturation in the growing rat

1. In growing rats, the time-course effects of giving a normal-protein diet (200 g casein/kg; NP) for 52 d, a low-protein diet (20 g casein/kg; LP) for 52 d and a LP diet for 26 d followed by balanced refeeding (200 g casein/kg; BR) for 26 d, on the fatty acid composition of liver total lipids and microsomal phospholipids were investigated together with delta 6- and delta 5-microsomal desaturase activities. 2. The oleic acid content (mg/g tissue) of liver total lipids increased progressively with the LP diet, while linoleic acid was increased only at days 7 and 52. 20:3 omega 6, 20:4 omega 6, 22:5 omega 6 and 22:6 omega 3 fatty acids decreased during the period on the LP diet. BR for 7 d was sufficient to restore the fatty acid composition of total lipids to control values. Changes in the fatty acid composition of liver microsomal L-alpha-phosphatidylcholines were observed only after 52 d on the LP diet; the proportions (% w/w total fatty acids) of 18:0, 20:3 omega 6 and 20:4 omega 6 fatty acids decreased while oleic acid increased. The fatty acid composition of L-alpha-phosphatidylethanolamines was less affected. 3. delta 6- and delta 5-desaturase activities decreased to 20-30% of their original values after 2 d on the LP diet; a smaller deficit prevailed after 14 d but disappeared after 25 d, to appear again after 52 d. As early as day 2 of BR, desaturase activities were greatly recovered and returned to control values at day 13. 4. The present work shows that modifications in microsomal delta 6- and delta 5-desaturase activities are not strictly paralleled by the changes in the composition of fatty acids of liver total lipids and microsomal phospholipids.     

Magnesium and lipids in cardiovascular disease.

Carbohydrate intolerance is positively correlated with animal fat consumption and is more common in beef eating populations. In contrast, individuals consuming diets comprised of polyunsaturated fats have a lower incidence of diabetes mellitus. To test the hypothesis that dietary fats may influence carbohydrate metabolism, serum glucose, insulin, and gastric inhibitory polypeptide (GIP) responses to three mixed test meals of varying fatty acid composition were assessed in 12 normal subjects. Fatty acids in the meals were either saturated fats or polyunsaturated fats derived from vegetables or fish. Each test meal provided 40% of a subject's calculated daily caloric requirement and contained approximately 45% carbohydrate, 40% fat, and 15% protein. Serum insulin responses were 62% higher (p less than 0.01) after the fish and 39% higher (p less than 0.01) after the vegetable meals compared to the saturated fat meal. No significant differences in insulin responses were observed between the vegetable and fish meals. Serum glucose concentration was slightly higher (p less than 0.02) during the fish meal than with the vegetable or saturated fat meals. The GIP levels were comparable following the fish and vegetable meals and were 25% lower than those observed with the saturated fat meal. These findings suggest that diets enriched with polyunsaturated fatty acids augment insulin secretion significantly more than a diet comprised primarily of saturated fatty acids. The mechanism for this increased insulin secretion is unknown but did not appear to be mediated through differences in serum glucose values or through the insulin-otrophic effects of GIP.(ABSTRACT TRUNCATED AT 250 WORDS)     

n-3 Fatty acids and 5-y risks of death and cardiovascular disease events in patients with coronary artery disease

BACKGROUND: Data on the association of n-3 fatty acid content in serum lipids with mortality in patients with coronary artery disease (CAD) are limited. OBJECTIVE: We hypothesized that a high proportion of n-3 fatty acids in serum lipids would be associated with reduced risks of death and coronary events in patients with established CAD. DESIGN: We measured dietary intakes via food records and the fatty acid composition of serum cholesteryl esters (CEs) in 285 men and 130 women with CAD (x age: 61 y; range: 33-74 y). The patients participating in the EUROASPIRE (European Action on Secondary Prevention through Intervention to Reduce Events) study were followed up for 5 y. RESULTS: During the follow-up, 36 patients died, 21 had myocardial infarctions, and 12 had strokes. The relative risks (RRs) of death adjusted for cardiovascular disease risk factors for subjects in the highest tertile of fatty acids in CEs compared with those in the lowest tertile were 0.33 (95% CI: 0.11, 0.96) for alpha-linolenic acid, 0.33 (0.12, 0.93) for eicosapentaenoic acid, and 0.31 (0.11, 0.87) for docosahexaenoic acid (P for trend = 0.063, 0.056, and 0.026, respectively). A high proportion of eicosapentaenoic acid in CEs was associated with a low risk of CAD death. Compared with no consumption, consumption of fish tended to be associated with a lower risk of death [1-57 g/d, RR = 0.50 (0.20, 1.28); > 57 g/d, RR = 0.37 (0.14, 1.00); P for trend = 0.059]. CONCLUSION: High proportions of n-3 fatty acids in serum lipids are associated with a substantially reduced risk of death.     

Association of the fatty acid profile of serum lipids with glucose and insulin metabolism during 2 fat-modified diets in subjects with impaired glucose tolerance

BACKGROUND: Both the amount and quality of dietary fat can modify glucose and insulin metabolism. OBJECTIVE: The objective was to examine the relation between serum lipid fatty acids and glucose metabolism before and after the consumption of a diet enriched in either monounsaturated (Mono diet) or polyunsaturated (Poly diet) fatty acids. DESIGN: After consuming a high-saturated-fat run-in diet for 3 wk, 31 subjects with impaired glucose tolerance were randomly counseled to consume the Mono [40% fat; 11%, 19%, and 8% of energy as saturated, monounsaturated, and polyunsaturated fatty acids (S:M:P), respectively] or the Poly (34% fat; S:M:P of 11%:10%:10%) diet for 8 wk. Serum lipid fatty acids were measured, and an intravenous-glucose-tolerance test was performed at baseline and at 8 wk. RESULTS: At baseline, a higher glucose effectiveness (S(G)) was associated with higher proportions of oleic (r = 0.57, P = 0.04) and alpha-linolenic (r = 0.64, P = 0.01) acids in phospholipids. An increase in the proportions of oleic and alpha-linolenic acids in phospholipids was associated with a decrease in fasting plasma glucose [r = -0.53 (P = 0.002) and r = -0.47 (P = 0.009), respectively]. An increase in the S(G) was associated with an increase in the proportion of oleic acid (r = 0.55, P = 0.004) and with a decrease in that of arachidonic acid (r = -0.40, P = 0.04) in phospholipids. CONCLUSIONS: The beneficial changes in fasting plasma glucose and in the S(G) during the Mono diet were associated with alterations in the proportions of oleic, alpha-linolenic, and arachidonic acids in phospholipids.     

Flaxseed on cardiovascular disease markers in healthy menopausal women: a randomized, double-blind, placebo-controlled trial

OBJECTIVE: Due to its high content of lignans, alpha-linolenic acid and fiber, flaxseed may reduce cardiovascular disease risk in humans. The present study evaluated the effect of flaxseed on markers of cardiovascular disease risk in healthy menopausal women. METHODS: One hundred ninety-nine women were randomly assigned to consume 40 g daily of flaxseed or wheat germ placebo for 12 mo. Fatty acids, apolipoproteins A-1 and B, lipoprotein(a), low-density lipoprotein particle size, fibrinogen, C-reactive protein, insulin, and glucose were measured at baseline and at 12 mo. RESULTS: In total 179 women were available for the intention-to-treat analysis. Flaxseed increased plasma alpha-linolenic (P < 0.0001), docosapentaenoic (P = 0.001), and total omega-3 fatty (P = 0.0004) acids. Differences between flaxseed and wheat germ were observed for apolipoprotein A-1 (-0.10 +/- 0.26 g/L, P = 0.011) and apolipoprotein B (-0.05 +/- 0.16 g/L, P = 0.047). From baseline, flaxseed raised apolipoproteins A-1 and B by 4.4% (P = 0.006) and 3% (P = 0.054), whereas wheat germ increased these apolipoproteins by 11.6% (P < 0.0001) and 7% (P = 0.0001), respectively. Both treatments increased lipoprotein(a) (P < 0.0001) and decreased low-density lipoprotein peak particle size (P < 0.0001). CONCLUSION: In this large, long-term, placebo-controlled trial in healthy menopausal women, flaxseed increased some omega-3 fatty acids in plasma and had a limited effect on apolipoprotein metabolism.     

Modification of plasma and hepatic lipids of guinea pigs by feeding high oleic acid pork compared with regular pork.

Meat from such monogastric animals as swine can be modified to substitute monounsaturated fatty acids for saturated fatty acids. Because monounsaturated fatty acids have a beneficial effect on serum lipids as compared with saturated fatty acids, the objective of this study was to assess the effect of modified pork as compared with regular pork on serum and hepatic lipids. Guinea pigs were fed diets containing pork from control diet-fed hogs or from hogs fed a diet containing high oleic acid sunflower oil. The pork provided almost all of the fat in the diets at the level of 4 and 15 g/100 g diet, 10 or 34% energy. The high oleic pork muscle and fat contained 26 and 46% less palmitic and stearic acids (the primary saturated fatty acids), respectively, and 31 and 29% more oleic acid (the primary monounsaturated fatty acid) than the regular pork muscle and fat, respectively. Cholesterol concentration of diets ranged from 0.06 to 0.08% of the diet. Although total serum cholesterol, HDL cholesterol and triglyceride concentrations did not differ due to type of pork, results indicated that serum LDL cholesterol was lower (15%) and hepatic cholesterol was greater (15%) in the high oleic pork, 15% fat group as compared with the control pork 15% fat group. Also, serum LDL cholesterol concentration was higher in the groups fed 15% fat compared with those fed 4% fat. In this study pork modified to have more oleic acid and less saturated fatty acids had a positive effect on tissue lipids when fed to animals.     

Plasma and red blood cell fatty acid composition in small for gestational age term infants fed human milk or formula

The purpose of the present study was to evaluate the effects of feeding human milk or milk formula on the fatty acid composition of plasma and red blood cell (RBC) lipids in at term small for gestational age infants (SGA) for the first 3 months of life. One group of infants received a formula with a linoleic:alpha-linolenic acid ratio of 10:1 (MF group). Another group served as control and received their own mother's milk (HM group). Blood samples were taken at birth and at 1 week, 4 weeks, and 3 months of life. Plasma and RBC fatty acid composition were analyzed by gas liquid chromatography and results of total plasma lipids were expressed as concentrations by adding an internal standard. Concentrations of saturated and monounsaturated fatty acids increased in total plasma lipids with age in all infants. In contrast, those fatty acids decreased when results were expressed as percentages of total fatty acids. Long-chain polyunsaturated fatty acids (LCP) decreased regardless of how results were expressed, but the absolute concentrations of these fatty acids in plasma available for tissue accretion were greater than suggested by the percentage results. Plasma and RBC docosahexaenoic acid (22:6n-3) decreased in the MF group in comparison to the HM group. Arachidonic acid (20:4n-6) was lower in plasma of MF-fed infant but not in RBC phospholipids. We conclude that term SGA infants fed an adapted milk formula with a linoleic:alpha-linolenic acid ratio of 10:1 but devoid of LCP may lead to a low n-3 LCP status.     

Food intake, serum lipids and amino acids of school children in agricultural communities in Japan

OBJECTIVE: To investigate the correlation among serum lipids, amino acids and diet of children in Japan where the mortality of ischemic heart disease is still very low. DESIGN: Cross-sectional study. SETTING: Two towns in Shimane prefecture, typical mountainous agricultural communities in the western part of the mainland of Japan. SUBJECTS: 514 children (10-15 y) in the communities were recruited. RESULTS: The mean cholesterol levels ranged from 3.9 to 4.4 mmol/l for boys and from 4.3 to 4.5 mmol/l for girls, and serum cholesterol level fell with age in boys. Serum cholesterol level of girls rose once between 11 and 13 y and fell gradually. Fish intake was positively correlated with serum omega-3 series fatty acids. Milk intake was negatively and soybean intake was positively correlated with omega-3/omega-6 series fatty acids ratio. Serum branched-chain amino acids were correlated negatively with serum polyunsaturated/saturated fatty acids ratio. CONCLUSIONS: Serum cholesterol level of children in agricultural communities in Japan has risen, and is probably affected by the change of food intake. Promoting the intake of soybean and fish, which are traditional Japanese foods, will be important in preventing atherosclerosis and ischemic heart disease. Attention should be paid to the relationship between branched-chain amino acids level in blood and fatty acids metabolism to verify the mechanism of the progress of atherosclerosis.