Long-chain Polyunsaturated Fatty Acid Ratio Research Articles

Effect of reducing the n−6:n−3 long-chain PUFA ratio during pregnancy and lactation on infant adipose tissue growth within the first year of life: an open-label randomized controlled trial

The composition of long-chain PUFAs (LCPUFAs) in the maternal diet may affect obesity risk in the mother's offspring. We hypothesized that a reduction in the n-6 (omega-6):n-3 (omega-3) LCPUFA ratio in the diet of pregnant women and breastfeeding mothers may prevent expansive adipose tissue growth in their infants during the first year of life. In a randomized controlled trial, 208 healthy pregnant women were randomly assigned to an intervention (1200 mg n-3 LCPUFAs as a supplement per day and a concomitant reduction in arachidonic acid intake) or a control diet from the 15th wk of pregnancy to 4 mo of lactation. The primary outcome was infant fat mass estimated by skinfold thickness (SFT) measurements at 4 body sites at 3-5 d, 6 wk, and 4 and 12 mo postpartum. Secondary endpoints included sonographic assessment of abdominal subcutaneous and preperitoneal fat, fat distribution, and child growth. Infants did not differ in the sum of their 4 SFTs at ≤1 y of life [intervention: 24.1 ± 4.4 mm (n = 85); control: 24.1 ± 4.1 mm (n = 80); mean difference: -0.0 mm (95% CI: -1.3, 1.3 mm)] or in growth. Likewise, longitudinal ultrasonography showed no significant differences in abdominal fat mass or fat distribution. We showed no evidence that supplementation with n-3 fatty acids and instructions to reduce arachidonic acid intake during pregnancy and lactation relevantly affects fat mass in offspring during the first year of life. Prospective long-term studies are needed to explore the efficacy of this dietary approach for primary prevention. This trial was registered at clinicaltrials.gov as NCT00362089.

Krill oil significantly decreases 2-arachidonoylglycerol plasma levels in obese subjects

We have previously shown that krill oil (KO), more efficiently than fish oil, was able to downregulate the endocannabinoid system in different tissues of obese zucker rats.We therefore aimed at investigating whether an intake of 2 g/d of either KO or menhaden oil (MO), which provides 309 mg/d of EPA/DHA 2:1 and 390 mg/d of EPA/DHA 1:1 respectively, or olive oil (OO) for four weeks, is able to modify plasma endocannabinoids in overweight and obese subjects.The results confirmed data in the literature describing increased levels of endocannabinoids in overweight and obese with respect to normo-weight subjects. KO, but not MO or OO, was able to significantly decrease 2-arachidonoylglycerol (2-AG), although only in obese subjects. In addition, the decrease of 2-AG was correlated to the plasma n-6/n-3 phospholipid long chain polyunsaturated fatty acid (LCPUFA) ratio. These data show for the first time in humans that relatively low doses of LCPUFA n-3 as KO can significantly decrease plasma 2-AG levels in obese subjects in relation to decrease of plasma phospholipid n-6/n-3 LCPUFA ratio. This effect is not linked to changes of metabolic syndrome parameters but is most likely due to a decrease of 2-AG biosynthesis caused by the replacement of 2-AG ultimate precursor, arachidonic acid, with n-3 PUFAs, as previously described in obese Zucker rats.

Effects of weight loss on liver and erythrocyte polyunsaturated fatty acid pattern and oxidative stress status in obese patients with non-alcoholic fatty liver disease.

Our aim was to study the influence of weight loss on the fatty acid (FA) composition of liver and erythrocyte phospholipids and oxidative stress status in obese, non-alcoholic, fatty liver disease (NAFLD) patients. Seven obese NAFLD patients who underwent subtotal gastrectomy with a gastro-jejunal anastomosis in roux and Y were studied immediately and 3 months after surgery. Seven non-obese patients who underwent anti-reflux surgery constituted the control group. Serum F2-isoprostane levels were measured by GS/NICI-MS/MS and FA composition was determined by GC. At the time of surgery, controls and obese patients exhibited a hepatic polyunsaturated fatty acid (PUFA) pattern that correlated with that of erythrocytes. Three months after surgery, NAFLD patients lost 21% of initial body weight; serum F2-isoprostane levels decreased by 76%; total PUFA, long-chain PUFA (LCPUFA), n-3 PUFA, and n-3 LCPUFA increased by 22, 29, 81, and 93%, respectively; n-6/n-3 LCPUFA ratio decreased by 51%; docosahexaenoic acid/docosapentaenoic acid ratio increased by 19-fold; and the n-3 product/precursor ratio (20: 5 + 22: 5 + 22: 6)/18: 3 increased by 164% (p<0.05). It is concluded that weight loss improves the n-3 LCPUFA status of obese patients in association with significant amelioration in the biomarkers of oxidative stress, membrane FA insaturation, and n-3 LCPUFA biosynthesis capacity, thus representing a central therapeutic issue in the improvement of obesity-related metabolic alterations involved in the mechanism of hepatic steatosis.

Effects of weight loss on liver and erythrocyte polyunsaturated fatty acid pattern and oxidative stress status in obese patients with non-alcoholic fatty liver disease

Our aim was to study the influence of weight loss on the fatty acid (FA) composition of liver and erythrocyte phospholipids and oxidative stress status in obese, non-alcoholic, fatty liver disease (NAFLD) patients. Seven obese NAFLD patients who underwent subtotal gastrectomy with a gastro-jejunal anastomosis in roux and Y were studied immediately and 3 months after surgery. Seven non-obese patients who underwent anti-reflux surgery constituted the control group. Serum F2-isoprostane levels were measured by GS/NICI-MS/MS and FA composition was determined by GC. At the time of surgery, controls and obese patients exhibited a hepatic polyunsaturated fatty acid (PUFA) pattern that correlated with that of erythrocytes. Three months after surgery, NAFLD patients lost 21% of initial body weight; serum F2-isoprostane levels decreased by 76%; total PUFA, long-chain PUFA (LCPUFA), n-3 PUFA, and n-3 LCPUFA increased by 22, 29, 81, and 93%, respectively; n-6/n-3 LCPUFA ratio decreased by 51%; docosahexaenoic acid/docosapentaenoic acid ratio increased by 19-fold; and the n-3 product/precursor ratio (20: 5 + 22: 5 + 22: 6)/18: 3 increased by 164% (p<0.05). It is concluded that weight loss improves the n-3 LCPUFA status of obese patients in association with significant amelioration in the biomarkers of oxidative stress, membrane FA insaturation, and n-3 LCPUFA biosynthesis capacity, thus representing a central therapeutic issue in the improvement of obesity-related metabolic alterations involved in the mechanism of hepatic steatosis.

Three-Year Tracking of Fatty Acid Composition of Plasma Phospholipids in Healthy Children

Objectives: The fatty acid composition of plasma phospholipids reflects the dietary fatty acid intake as well as endogenous turnover. We aimed at investigating the potential tracking of plasma phospholipid fatty acid composition in children that participated in a prospective cohort study. Methods: 26 healthy children participated in a longitudinal study on health risks and had been enrolled after birth. All children were born at term with birth weights appropriate for gestational age. Follow-up took place at ages 24, 36 and 60 months. At each time point a 24-hour dietary recall was obtained, anthropometric parameters were measured and a blood sample for phospholipid fatty acid analysis was taken. Results: Dietary intake of saturated (SFA), monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids at the three time points were not correlated. We found lower values for plasma MUFA and the MUFA/SFA ratio at 60 months compared to 24 months. In contrast, total PUFA, total n–6 and n–6 long-chain polyunsaturated fatty acids (LC-PUFA) were higher at 60 months. Significant averaged correlation coefficients (average of Pearson’s R for 24 versus 36 months and 36 versus 60 months) were found for n–6 LC-PUFA (r = 0.67), n–6/n–3 LC-PUFA ratio (r = 0.59) and arachidonic acid/linoleic acid ratio (r = 0.64). Partial tracking was found for the docosahexaenoic acid/α-linolenic acid ratio (r = 0.33). Body mass index and sum of skinfolds Z-scores were similar in the three evaluations. Conclusions: A significant tracking of n–6 LC-PUFA, n–6 LC-PUFA/n–3 LC-PUFA ratio, arachidonic acid/linoleic acid ratio and docosahexaenoic acid/α-linolenic acid ratio may reflect an influence of individual endogenous fatty acid metabolism on plasma concentrations of some, but not all, fatty acids.

Fish oil and mental health: the role of n-3 long-chain polyunsaturated fatty acids in cognitive development and neurological disorders

Epidemiological and experimental studies have indicated that consumption of more n-3 long-chain polyunsaturated fatty acids may reduce the risk for a variety of diseases, including cardiovascular, neurological and immunological disorders, diabetes and cancer. This article focuses on the role of marine n-3 long-chain polyunsaturated fatty acids in brain functions, including the development of the central nervous system and neurological disorders. An overview of the major animal studies and clinical trials is provided here, focusing on fatty acid supplementation during pregnancy and infancy, and prevention and management of Alzheimer's disease, schizophrenia, depression and attention deficit hyperactive disorder. Although an optimal balance in n-3/n-6 long-chain polyunsaturated fatty acid ratio is important for proper neurodevelopment and cognitive functions, results from randomized controlled trials are controversial and do not confirm any useful effect of supplementation on development of preterm and term infants. The relationship between fatty acid status and mental disorders is confirmed by reduced levels of n-3 long-chain polyunsaturated fatty acids in erythrocyte membranes of patients with central nervous system disorders. Nevertheless, there are very little data supporting the use of fish oil in those patients. The only way to verify whether n-3 long-chain polyunsaturated fatty acids are a potential therapeutic option in the management and prevention of mental disorders is to conduct a large definitive randomized controlled trials similar to those required for the licensing of any new pharmacological treatment.

High proportions of n‐6 polyunsaturated fatty acids in mature milk of mothers in Ouagadougou, Burkina Faso

Milk from 101 mothers living in Ouagadougou (Burkina Faso) showed a mean lipid content of 33.42 g/l and a fatty acid composition strongly related to the mothers' dietary habits: high proportions of linoleic acid (19.80%), n-6 long-chain polyunsaturated fatty acids (1.90%), and 8:0-14:0 saturated fatty acids (26.94%). The proportions of alpha-linolenic acid (0.45%) and n-3 long-chain polyunsaturated fatty acids (0.44%) were low. The 18:2/18:3 and n-6/n-3 long-chain polyunsaturated fatty acids ratios (53:1 and 5:1, respectively) were well above recommendations.

High proportions of n-6 polyunsaturated fatty acids in mature milk of mothers in Ouagadougou, Burkina Faso

Milk from 101 mothers living in Ouagadougou (Burkina Faso) showed a mean lipid content of 33.42 g/l and a fatty acid composition strongly related to the mothers' dietary habits: high proportions of linoleic acid (19.80%), n-6 long-chain polyunsaturated fatty acids (1.90%), and 8:0– 14:0 saturated fatty acids (26.94%). Conclusion: The proportions of α-linolenic acid (0.45%) and n-3 long-chain polyunsaturated fatty acids (0.44%) were low. The 18:2 /18:3 and n-6/n-3 long-chain polyunsaturated fatty acids ratios (53:1 and 5:1, respectively) were well above recommendations.

The fatty acid composition of human colostrum.

We reviewed 15 studies reporting on the fatty acid composition of colostrum lipids from 16 geographic regions: 11 European studies and one study each from Central America, the Caribbean, Australia and Asia. The contents of essential fatty acids, saturates and polyunsaturates were similar in the southern European countries Spain, Slovenia and France. Colostrum of St. Lucian women was high in saturates and low in oleic acid, reflecting a high-carbohydrate, low-fat diet. Abundant fish intake was reflected in high contents of docosahexaenoic acid and total n-3 long-chain polyunsaturated fatty acids in St. Lucia. Two French studies published with an interval of two years showed a very similar colostrum fatty acid composition, whereas two German studies obtained with an interval of 14 years showed higher docosahexaenoic acid and arachidonic acid contents in the later study, with an unchanged n-6/n-3 long-chain polyunsaturated fatty acid ratio. Studies from Spain reported a decline of alpha-linolenic acid in colostrum over a time period of 13 years. Colostrum of Australian women contained the lowest polyunsaturated/saturated and n-6/n-3 long-chain polyunsaturated fatty acids ratios (0.28 and 1.58) and the lowest contents of linoleic and alpha-linolenic acids (7.8 and 0.4 wt.%). In contrast, the contents of docosahexaenoic acid, eicosapentaenoic acid and total n-3 long-chain polyunsaturated fatty acids (0.6, 0.4 and 1.4 wt.%) were higher in Australian than in European samples. Fatty acid composition of human colostrum appears to be markedly influenced by geographic differences in maternal dietary composition.

69 RELATIONSHIPS BETWEEN ARACHIDONIC ACID AND DOCOSAHEXAENOIC ACID IN HUMAN MILK OVER 6 MONTHS OF LACTATION.

Aims. To investigate the relationships of the major n-6 long-chain polyunsaturated fatty acid (LC-PUFA), arachidonic acid (AA, 20:4n-6), to the major n-3 LC-PUFA, eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3), during prolonged lactation. Methods. Recruitment of mothers after delivery of full-term infants (37-42 weeks gestational age). Collection of pooled breast milk (hindmilk) from all the feedings over 24 hours at the following points: first day (colostrum), 25±5 days, 3 months, 6 months of lactation. Extraction of lipids from aliquots of each day collection with chloroform-methanol and analysis of FA methyl esters by capillary gas-chromatography. Statistical analysis by linear regression. Results. Ninety-five mothers living in the Milan area were recruited. Significant preliminary observations are reported in the table. Conclusions. While no relationship is present between the major n-6 and n-3 LC-PUFA in colostrum, in late lactation the relationships become more relevant. Since the major LC-PUFA concentrations of breast milk show reductions with time (Am J Clin Nutr 1995; 61:1231), we speculate that a coordinated process for both n-6 and n-3 LC-PUFA synthesis and/or secretion in milk operates in the late phases of lactation to provide the infant with a relatively constant n-6/n-3 LC-PUFA ratio.