Omega-3 polyunsaturated fatty acids in adolescents: knowledge and consumption

Familial risk for bipolar I disorder is associated with erythrocyte omega-3 polyunsaturated fatty acid deficits in youth with attention-deficit hyperactivity disorder

Although attention-deficit/hyperactivity disorder (ADHD) and a family history of bipolar I disorder (BD) increase the risk for developing BD, associated pathoetiological mechanisms remain poorly understood. One candidate risk factor is a neurodevelopmental deficiency in omega-3 polyunsaturated fatty acids, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). This study investigated erythrocyte EPA+DHA biostatus in psychostimulant-free ADHD youth with ('high-risk', HR) and without ('low-risk', LR) a first-degree relative with BD, and healthy controls (HC). Erythrocyte EPA+DHA composition was determined by gas chromatography, and symptom ratings were performed. A total of n = 123 (HR, n = 41; LR, n = 42; HC, n = 40) youth (mean age: 14.4 ± 2.5 years) were included in the analysis. Compared with HC, erythrocyte EPA+DHA composition was significantly lower in HR (-13%) but not LR (-3%), and there was a trend for HR to be lower than LR (-11%). Both HR and LR differed significantly from HC on all symptom ratings. HR had greater ADHD hyperactivity/impulsive symptom severity, manic symptom severity, and higher parent-reported ratings of internalization, externalization, and dysregulation, compared with LR. ADHD youth with a BD family history exhibit erythrocyte EPA+DHA deficits and a more severe clinical profile, including greater manic and dysregulation symptoms, compared with ADHD youth without a BD family history.

Awareness of Omega-3 Fatty Acids and Possible Health Effects among Young Adults

PURPOSE

To assess awareness of omega-3 fatty acids (FAs) and their possible health effects among young adults.

METHODS

An online survey was deployed to young adults. Questionnaire development involved identification of topic areas by content experts and adaptation of questions from previous consumer surveys. Focus groups and cognitive interviews ensured face validity, feasibility, and clarity of survey questions. Degrees of awareness and self-reported consumption were assessed by descriptive statistics and associations by Cochran's Q tests, Pearson's χ² tests, Z-tests, and logistic regression.

RESULTS

Of the 834 survey completers (aged 18-25 years), more respondents recognized the abbreviations EPA (∼51%) and DHA (∼66%) relative to ALA (∼40%; P ≤ 0.01). Most respondents (∼83%) recognized that EPA and DHA have been linked to heart and brain health. Respondents who used academic/reputable sources, healthcare professionals, and/or social media to obtain nutritional information were more likely to report awareness of these health effects (P ≤ 0.01). Finally, 48% of respondents reported purchasing or consuming omega-3 foods, while 21% reported taking omega-3 supplements.

CONCLUSIONS

This baseline survey suggests a high level of awareness of some aspects of omega-3 fats and health in a sample of young adults, and social media has become a prominent source of nutrition and health information.

Polyunsaturated fatty acids and recurrent mood disorders: Phenomenology, mechanisms, and clinical application

A body of evidence has implicated dietary deficiency in omega-3 polyunsaturated fatty acids (n-3 PUFA), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in the pathophysiology and etiology of recurrent mood disorders including major depressive disorder (MDD) and bipolar disorder. Cross-national and cross-sectional evidence suggests that greater habitual intake of n-3 PUFA is associated with reduced risk for developing mood symptoms. Meta-analyses provide strong evidence that patients with mood disorders exhibit low blood n-3 PUFA levels which are associated with increased risk for the initial development of mood symptoms in response to inflammation. While the etiology of this n-3 PUFA deficit may be multifactorial, n-3 PUFA supplementation is sufficient to correct this deficit and may also have antidepressant effects. Rodent studies suggest that n-3 PUFA deficiency during perinatal development can recapitulate key neuropathological, neurochemical, and behavioral features associated with mood disorders. Clinical neuroimaging studies suggest that low n-3 PUFA biostatus is associated with abnormalities in cortical structure and function also observed in mood disorders. Collectively, these findings implicate dietary n-3 PUFA insufficiency, particularly during development, in the pathophysiology of mood dysregulation, and support implementation of routine screening for and treatment of n-3 PUFA deficiency in patients with mood disorders.

Association between Adherence to the Mediterranean Diet and Presence of Nonalcoholic Fatty Liver Disease in Children

OBJECTIVE

The study's objective was to analyze the association between the adherence to the Mediterranean diet (MD) and the presence of nonalcoholic fatty liver disease (NAFLD) in children.

METHODS

The study consisted of three groups of children. Group 1 included obese/overweight children with recent diagnosis of NAFLD (n = 106, 12.4 ± 2.6 years). Group 2 included obese children without NAFLD (n = 21, 11.3 ± 2.6 years). Group 3 included the healthy children (without known chronic disease) with normal BMI (n = 54, 11.8 ± 2.9 years). Compliance to the MD was assessed by the KIDMED index score.

RESULTS

KIDMED index score in obese children with NAFLD, without NAFLD, and healthy children were 2.6 ± 2.4, 4.6 ± 1.2, and 6.2 ± 1.9, respectively (p < 0.05 for group 1 versus 2, 1 versus 3, and 2 versus 3). Diet compliance was good in only 4.7% of the patients with NAFLD, whereas it was 31.5% in healthy children. KIDMED index score was negatively correlated with BMI (p < 0.05, r = -0.53), but no correlation was found with other parameters. The area under the receiver operation curve (AUROC) for predicting fatty liver disease in obese children (n = 127) with BMI and KIDMED index score was 0.78 (p < 0.05) and 0.24 (p < 0.05), respectively. BMI >26 has a sensitivity of 79.2% and specificity of 52.4%, and KIDMED index score ≤3 has a sensitivity of 66.9% and specificity of 76.1%.

CONCLUSIONS

MD is an inexpensive and nontoxic dietary regimen and may be used as a therapeutic option in obese children with NAFLD.

Adolescents with or at ultra-high risk for bipolar disorder exhibit erythrocyte docosahexaenoic acid and eicosapentaenoic acid deficits: a candidate prodromal risk biomarker

AIM

Mood disorders are associated with low levels of the long-chain omega-3 (LCn-3) fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). This study investigated LCn-3 fatty acid biostatus in youth with or at varying risk for developing mania to assess its utility as a prodromal risk biomarker.

METHOD

Erythrocyte fatty acid composition was determined in healthy adolescents (n = 28, HC), asymptomatic adolescents with a biological parent with bipolar I disorder (n = 30; 'high risk', HR), adolescents with a biological parent with bipolar I disorder and major depressive disorder, or depressive disorder not otherwise specified (n = 36; 'ultra-high risk', UHR), and first-episode adolescent bipolar manic patients (n = 35, BP).

RESULTS

Group differences were observed for DHA (P ≤ 0.0001) and EPA (P = 0.03). Compared with HC, erythrocyte EPA + DHA ('omega-3 index') was significantly lower in BP (-24%, P ≤ 0.0001) and UHR (-19%, P = 0.0006) groups, and there was a trend in the HR group (-11%, P = 0.06). Compared with HC (61%), a greater percentage of HR (77%, P = 0.02), UHR (80%, P = 0.005) and BP (97%, P = 0.001) subjects exhibited EPA + DHA levels of ≤4.0%. Among all subjects (n = 130), EPA + DHA was inversely correlated with manic (r = -0.29, P = 0.0008) and depressive (r = -0.28, P = 0.003) symptom severity. The AA/EPA + DHA ratio was significantly greater in BP (+22%, P = 0.0002) and UHR (+16%, P = 0.001) groups.

CONCLUSIONS

Low EPA + DHA levels coincide with the initial onset of mania, and increasing risk for developing bipolar disorder is associated with graded erythrocyte EPA + DHA deficits. Low erythrocyte EPA + DHA biostatus may represent a promising prodromal risk biomarker warranting additional evaluation in future prospective studies.

Detection and Treatment of Long-Chain Omega-3 Fatty Acid Deficiency in Adolescents with SSRI-Resistant Major Depressive Disorder

Residual depressive symptoms are commonly observed in adolescents with major depressive disorder (MDD) following treatment with selective serotonin reuptake inhibitors (SSRIs). This study combined a case-control analysis and an open-label fish oil (FO) trial to investigate the relationship between long-chain omega-3 (LCn-3) fatty acid status and residual depressive symptoms in SSRI-resistant adolescent MDD patients. Baseline erythrocyte docosahexaenoic acid (DHA)(-28%, p=0.0003), but not eicosapentaenoic acid (EPA)(-18%, p=0.2), was significantly lower in patients (n=20) compared with healthy controls (n=20). Patients receiving 10-week low-dose (2.4 g/d, n=7) and high-dose (16.2 g/d, n=7) FO exhibited significant increases in erythrocyte EPA and DHA composition. In the intent-to-treat sample, depressive symptoms decreased significantly in the high-dose group (n=7, -40%, p<0.0001), and there was a trend in the low-dose group (n=10, -20%, p=0.06). Symptom remission was observed in 40% of patients in the low-dose group and 100% of patients in the high-dose group. There were no significant changes in vital signs and adverse events were rated as mild or moderate in severity. These preliminary findings demonstrate that adolescents with SSRI-resistant depression exhibit robust DHA deficits, and suggest that adjunctive FO supplementation is well-tolerated and effective for increasing LCn-3 fatty acid status and augmenting SSRI antidepressant effects.

Estimation of fish and ω-3 fatty acid intake in pediatric nonalcoholic fatty liver disease

AIMS

Fish and ω-3 fatty acids are reported to be beneficial in pediatric nonalcoholic fatty liver disease (NAFLD), but no studies have assessed their relation to histological severity. The objectives of this study were to evaluate the dietary intake of fish and ω-3 fatty acids in children with biopsy-proven NAFLD, and examine their association with serological and histological indicators of disease.

METHODS

This was a cross-sectional analysis of 223 children (6-18 years) who participated in the Treatment of Nonalcoholic Fatty Liver Disease in Children trial or the NAFLD Database study conducted by the Nonalcoholic Steatohepatitis Clinical Research Network. The distribution of fish and ω-3 fatty acid intake was determined from responses to the Block Brief 2000 Food Frequency Questionnaire, and analyzed for associations with serum alanine aminotransferase, histological features of fatty liver disease, and diagnosis of steatohepatitis after adjusting for demographic, anthropometric, and dietary variables.

RESULTS

The minority of subjects consumed the recommended 8 ounces of fish per week (22/223 [10%]) and 200 mg of long-chain ω-3 fatty acids per day (12/223 [5%]). Lack of fish and long-chain ω-3 fatty acid intake was associated with greater portal (P = 0.03 and P = 0.10, respectively) and lobular inflammation (P = 0.09 and P = 0.004, respectively) after controlling for potential confounders.

CONCLUSIONS

Fish and ω-3 fatty acid intake was insufficient in children with NAFLD, which may increase susceptibility to hepatic inflammation. Patients with pediatric NAFLD should be encouraged to consume the recommended amount of fish per week.

A double-blind, placebo-controlled trial of ω-3 fatty acids in Tourette's disorder

OBJECTIVE

Clinical observations have suggested therapeutic effects for ω-3 fatty acids (O3FA) in Tourette's disorder (TD), but no randomized, controlled trials have been reported. In a placebo-controlled trial, we examined the efficacy of O3FA in children and adolescents with TD.

METHODS

Thirty-three children and adolescents (ages 6-18) with TD were randomly assigned, double-blind, to O3FA or placebo for 20 weeks. O3FA consisted of combined eicosapentaenoic acid and docosahexaenoic acid. Placebo was olive oil. Groups were compared by using (1) intent-to-treat design, with the last-observation-carried-forward controlling for baseline measures and attention-deficit/hyperactivity disorder via (a) logistic regression, comparing percentage of responders on the primary Yale Global Tic Severity Scale (YGTSS)-Tic and secondary (YGTSS-Global and YGTSS-Impairment) outcome measures and (b) analysis of covariance; and (2) longitudinal mixed-effects models.

RESULTS

At end point, subjects treated with O3FA did not have significantly higher response rates or lower mean scores on the YGTSS-Tic (53% vs 38%; 15.6 ± 1.6 vs 17.1 ± 1.6, P > .1). However, significantly more subjects on O3FA were considered responders on the YGTSS-Global measure (53% vs 31%, P = .05) and YGTSS-Impairment measure (59% vs 25%, P < .05), and mean YGTSS-Global scores were significantly lower in the O3FA-treated group than in the placebo group (31.7 ± 2.9 vs 40.9 ± 3.0, P = .04). Obsessive-compulsive, anxiety, and depressive symptoms were not significantly affected by O3FA. Longitudinal analysis did not yield group differences on any of the measures.

CONCLUSIONS

O3FA did not reduce tic scores, but it may be beneficial in reduction of tic-related impairment for some children and adolescents with TD. Limitations include the small sample and the possible therapeutic effects of olive oil.

Dietary fatty acid intake, its food sources and determinants in European adolescents: the HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence) Study

Dietary fatty acids (FA) play a role in several (patho)physiological processes at any age, and different FA have different effects on lipid status and health outcome. The present study aims to describe the FA intake and its main food sources in a population of healthy European adolescents and to assess the variation in intake as a function of non-dietary factors. FA intake was assessed with 24 h recall interviews in 1804 adolescents aged 12·5-17·5 years. Usual intakes were calculated using the multiple source method. Multilevel analyses, adjusting for study centre, were used to investigate the influence of non-dietary factors. The mean total fat intake was 33·3 (sd 1·2) % of total energy intake (%E). The mean SFA intake was 13·8 (sd 1·2) %E, with 99·8 % of the population exceeding the recommendations. SFA was mainly delivered by meat and cake, pies and biscuits. In most adolescents, the PUFA intake was too low, and 35·5 % of the population did not achieve the minimum recommended intake for α-linolenic acid (ALA). The main determinants of FA intake in the present study population were age and sex, as well as physical activity in the male subgroup. No contributions of body composition, socio-economic status or sexual maturation to the variance in FA intake were observed. In conclusion, the most important public health concerns regarding FA intake in this adolescent population were the low intake of ALA and the high intake of SFA, mainly seen in the younger-aged boys. In this group the major contributor to SFA was meat.

Fish oil and the management of hypertriglyceridemia

Hypertriglyceridemia, regarded as one of the independent clinical markers of metabolic syndrome, is a frequently observed disorder that has been shown to be common in the Arab region. Epidemiologic and clinical trials demonstrated that omega-3 fatty acids have the potential to reduce the incidence of cardiovascular disease (CVD); one of the mechanisms by which this effect is achieved is through reducing plasma triglyceride levels. There is strong scientific evidence from human trials that omega-3 fatty acids from either fish or fish oil supplements significantly reduce blood triglyceride levels and these benefits appear to be dose-dependent. The active ingredients of fish oils include the long chain fatty acids EPA and DHA. The ideal amount of omega-3 fatty acid that should be incorporated into the diet without provoking detrimental effects on other lipid components such as decreasing HDL-C and/or increasing LDL-C has not yet been elucidated. Presently, a prescription form of omega-3 fatty acid has been approved by the United States Food and Drug Administration (USFDA) as an adjunct to the diet for the treatment of very high triglyceride levels (> or = 500 mg/dl) in adults. Patients with hypertriglyceridemia have been shown to respond well to the use of omega-3 fatty acids even when used in conjunction with statins where greater improvements in the lipid profile were found as compared to treatment with statins alone. A determinant of the responsiveness to fish oil could be attributed to the ApoE genotype of individuals.

Fish consumption and its motives in households with versus without self-reported medical history of CVD: a consumer survey from five European countries

Background

The purpose of this study was to explore the cross-cultural differences in the frequency of fish intake and in motivations for fish consumption between people from households with (CVD+) or without (CVD-) medical history of cardiovascular disease, using data obtained in five European countries.

Methods

A cross-sectional consumer survey was carried out in November-December 2004 with representative household samples from Belgium, the Netherlands, Denmark, Poland and Spain. The sample consisted of 4,786 respondents, aged 18–84 and who were responsible for food purchasing and cooking in the household.

Results

Individuals from households in the CVD+ group consumed fish more frequently in Belgium and in Denmark as compared to those in the CVD- group. The consumption of fatty fish, which is the main sources of omega-3 PUFA associated with prevention of cardiovascular diseases, was on the same level for the two CVD groups in the majority of the countries, except in Belgium where CVD+ subjects reported to eat fatty fish significantly more frequently than CVD- subjects. All respondents perceived fish as a very healthy and nutritious food product. Only Danish consumers reported a higher subjective and objective knowledge related to nutrition issues about fish. In the other countries, objective knowledge about fish was on a low level, similar for CVD+ as for CVD- subjects, despite a higher claimed use of medical information sources about fish among CVD+ subjects.

Conclusion

Although a number of differences between CVD- and CVD+ subjects with respect to their frequency of fish intake are uncovered, the findings suggest that fish consumption traditions and habits – rather than a medical history of CVD – account for large differences between the countries, particularly in fatty fish consumption. This study exemplifies the need for nutrition education and more effective communication about fish, not only to the people facing chronic diseases, but also to the broader public. European consumers are convinced that eating fish is healthy, but particular emphasis should be made on communicating benefits especially from fatty fish consumption.

One generation of n-3 polyunsaturated fatty acid deprivation increases depression and aggression test scores in rats

Male rat pups at weaning (21 days of age) were subjected to a diet deficient or adequate in n-3 polyunsaturated fatty acids (n-3 PUFAs) for 15 weeks. Performance on tests of locomotor activity, depression, and aggression was measured in that order during the ensuing 3 weeks, after which brain lipid composition was determined. In the n-3 PUFA-deprived rats, compared with n-3 PUFA-adequate rats, docosahexaenoic acid (22:6n-3) in brain phospholipid was reduced by 36% and docosapentaenoic acid (22:5n-6) was elevated by 90%, whereas brain phospholipid concentrations were unchanged. N-3 PUFA-deprived rats had a significantly increased (P = 0.03) score on the Porsolt forced-swim test for depression, and increased blocking time (P = 0.03) and blocking number (P = 0.04) scores (uncorrected for multiple comparisons) on the isolation-induced resident-intruder test for aggression. Large effect sizes (d > 0.8) were found on the depression score and on the blocking time score of the aggression test. Scores on the open-field test for locomotor activity did not differ significantly between groups, and had only small to medium effect sizes. This single-generational n-3 PUFA-deprived rat model, which demonstrated significant changes in brain lipid composition and in test scores for depression and aggression, may be useful for elucidating the contribution of disturbed brain PUFA metabolism to human depression, aggression, and bipolar disorder.

Dose effect of alpha-linolenic acid on lipid metabolism in the hamster

In order to meet dietary requirements, the consumption of alpha-linolenic acid (ALA, 18:3 n-3) must be promoted. However, its effects on triglyceride (TG) and cholesterol metabolism are still controversial, and may be dose-dependent. The effects of increasing dietary ALA intakes (1%, 10%, 20% and 40% of total FA) were investigated in male hamsters. ALA replaced oleic acid while linoleic and saturated FA were kept constant. Triglyceridemia decreased by 45% in response to 10% dietary ALA and was not affected by higher intakes. It was associated with lower hepatic total activities of acetyl-CoA-carboxylase (up to -29%) and malic enzyme (up to -42%), which were negatively correlated to ALA intake (r(2) = 0.33 and r(2) = 0.38, respectively). Adipose tissue lipogenesis was 2-6 fold lower than in the liver and was not affected by dietary treatment. Substitution of 10% ALA for oleic acid increased cholesterolemia by 15% but, as in TG, higher ALA intakes did not amplify the response. The highest ALA intake (40%) dramatically modified the hepatobiliary metabolism of sterols: cholesterol content fell by 45% in the liver and increased by 28% in the faeces. Besides, faecal bile acids decreased by 61%, and contained more hydrophobic and less secondary bile acids. Thus, replacing 10% oleic acid by ALA is sufficient to exert a beneficial hypotriglyceridemic effect, which may be counteracted by the slight increase in cholesterolemia. Higher intakes did not modify these parameters, but a very high dose resulted in adverse effects on sterol metabolism.

Dietary intake of differently fed salmon; the influence on markers of human atherosclerosis

BACKGROUND

Cardioprotective effects of omega-3 polyunsaturated fatty acids (n-3 PUFAs) of marine origin are well recognized. Because of the shortness of marine resources vegetable oils are increasingly used in fish farming. The effects on human health of fish fed on vegetable oils are largely unknown.

METHODS

In a double-blinded intervention study, 60 patients with coronary heart disease (CHD) were randomly allocated to three groups consuming approximately 700 g per week for 6 weeks of differently fed Atlantic salmon: 100% fish oil (FO), 100% rapeseed oil (RO) or 50% of each (FO/RO), resulting in fillets with high, intermediate and low levels of marine n-3 PUFAs. Patient analyses before and after the intervention period included serum fatty acid profile, serum lipoproteins, and markers of vascular inflammation.

RESULTS

The serum fatty acid profiles of the patients after the intervention mirrored those of the corresponding salmon fillets and the respective salmon feeds. Significant differences between the groups were obtained, especially for the levels of total n-3 PUFAs and the n-3/n-6 FA ratio, which were markedly increased in the FO group in contrast to the two other groups (P < 0.02 for all). Additionally, significant reductions of serum triglycerides and of vascular cell adhesion molecule-1 and interleukin-6 were obtained in patients receiving the FO diet when compared with the two other groups (P < 0.05 for all).

CONCLUSIONS

Tailor-made Atlantic salmon fillets very high in n-3 PUFAs of marine origin seem to impose favourable biochemical changes in patients with CHD when compared with ingestion of fillets with intermediate and low levels of marine n-3 PUFAs, when replaced by rapeseed oil.

Half-lives of docosahexaenoic acid in rat brain phospholipids are prolonged by 15 weeks of nutritional deprivation of n-3 polyunsaturated fatty acids

Male rat pups (21 days old) were placed on a diet deficient in n-3 polyunsaturated fatty acids (PUFAs) or on an n-3 PUFA adequate diet containing alpha-linolenic acid (alpha-LNA; 18 : 3n-3). After 15 weeks on a diet, [4,5-3H]docosahexaenoic acid (DHA; 22 : 6n-3) was injected into the right lateral cerebral ventricle, and the rats were killed at fixed times over a period of 60 days. Compared with the adequate diet, 15 weeks of n-3 PUFA deprivation reduced plasma DHA by 89% and brain DHA by 37%; these DHA concentrations did not change thereafter. In the n-3 PUFA adequate rats, DHA loss half-lives, calculated by plotting log10 (DHA radioactivity) against time after tracer injection, equaled 33 days in total brain phospholipid, 23 days in phosphatidylcholine, 32 days in phosphatidylethanolamine, 24 days in phosphatidylinositol and 58 days in phosphatidylserine; all had a decay slope significantly greater than 0 (p < 0.05). In the n-3 PUFA deprived rats, these half-lives were prolonged twofold or greater, and calculated rates of DHA loss from brain, Jout, were reduced. Mechanisms must exist in the adult rat brain to minimize DHA metabolic loss, and to do so even more effectively in the face of reduced n-3 PUFA availability for only 15 weeks.

Dose effect of α-linolenic acid on PUFA conversion, bioavailability, and storage in the hamster

If an increased consumption of alpha-linolenic acid (ALA) is to be promoted in parallel with that of n-3 long-chain-rich food, it is necessary to consider to what extent dietary ALA can be absorbed, transported, stored, and converted into long-chain derivatives. We investigated these processes in male hamsters, over a broad range of supply as linseed oil (0.37, 3.5, 6.9, and 14.6% energy). Linoleic acid (LA) was kept constant (8.5% energy), and the LA/ALA ratio was varied from 22.5 to 0.6. The apparent absorption of individual FA was very high (>96%), and that of ALA remained almost maximum even at the largest supply (99.5%). The capacity for ALA transport and storage had no limitation over the chosen range of dietary intake. Indeed, ALA intake was significantly correlated with ALA level not only in cholesteryl esters (from 0.3 to 9.7% of total FA) but also in plasma phospholipids and red blood cells (RBC), which makes blood components extremely reliable as biomarkers of ALA consumption. Similarly, ALA storage in adipose tissue increased from 0.85 to 14% of total FA and was highly correlated with ALA intake. As for bioconversion, dietary ALA failed to increase 22:6n-3, decreased 20:4n-6, and efficiently increased 20:5n-3 (EPA) in RBC and cardiomyocytes. EPA accumulation did not tend to plateau, in accordance with identical activities of delta5- and delta6-desaturases in all groups. Dietary supply of ALA was therefore a very efficient means of improving the 20:4n-6 to 20:5n-3 balance.

Dietary intakes and food sources of omega-6 and omega-3 polyunsaturated fatty acids

Both n-6 and n-3 polyunsaturated fatty acids (PUFA) are recognized as essential nutrients in the human diet, yet reliable data on population intakes are limited. The aim of the present study was to ascertain the dietary intakes and food sources of individual n-6 and n-3 PUFA in the Australian population. An existing database with fatty acid composition data on 1690 foods was updated with newly validated data on 150 foods to estimate the fatty acid content of foods recorded as eaten by 10,851 adults in the 1995 Australian National Nutrition Survey. Average daily intakes of linoleic (LA), arachidonic (AA), alpha-linolenic (LNA), eicosapentaenoic (EPA), docosapentaenoic (DPA), and docosahexaenoic (DHA) acids were 10.8, 0.052, 1.17, 0.056, 0.026, and 0.106 g, respectively, with long-chain (LC) n-3 PUFA (addition of EPA, DPA, and DHA) totaling 0.189 g; median intakes were considerably lower (9.0 g LA, 0.024 g AA, 0.95 g LNA, 0.008 g EPA, 0.006 g DPA, 0.015 g DHA, and 0.029 g LC n-3 PUFA). Fats and oils, meat and poultry, cereal-based products and cereals, vegetables, and nuts and seeds were important sources of n-6 PUFA, while cereal-based products, fats and oils, meat and poultry, cereals, milk products, and vegetable products were sources of LNA. As expected, seafood was the main source of LC n-3 PUFA, contributing 71%, while meat and eggs contributed 20 and 6%, respectively. The results indicate that the majority of Australians are failing to meet intake recommendations for LC n-3 PUFA (> 0.2 g per day) and emphasize the need for strategies to increase the availability and consumption of n-3-containing foods.