Studies reporting blood levels of the omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), were systematically identified in order to create a global map identifying countries and regions with different blood levels. Included studies were those of healthy adults, published in 1980 or later. A total of 298 studies met all inclusion criteria. Studies reported fatty acids in various blood fractions including plasma total lipids (33%), plasma phospholipid (32%), erythrocytes (32%) and whole blood (3.0%). Fatty acid data from each blood fraction were converted to relative weight percentages (wt.%) and then assigned to one of four discrete ranges (high, moderate, low, very low) corresponding to wt.% EPA+DHA in erythrocyte equivalents. Regions with high EPA+DHA blood levels (>8%) included the Sea of Japan, Scandinavia, and areas with indigenous populations or populations not fully adapted to Westernized food habits. Very low blood levels (≤4%) were observed in North America, Central and South America, Europe, the Middle East, Southeast Asia, and Africa. The present review reveals considerable variability in blood levels of EPA+DHA and the very low to low range of blood EPA+DHA for most of the world may increase global risk for chronic disease.

Reduced intake of n−3 long-chain polyunsaturated fatty acids (LCPUFAs) may be a contributing factor to the increasing prevalence of wheezing disorders. We assessed the effect of supplementation with n−3 LCPUFAs in pregnant women on the risk of persistent wheeze and asthma in their offspring.

Conventional sample preparation for fatty acid analysis is a complicated, multiple-step process, and gas chromatography (GC) analysis alone can require >1 h per sample to resolve fatty acid methyl esters (FAMEs). Fast GC analysis was adapted to human plasma FAME analysis using a modified polyethylene glycol column with smaller internal diameters, thinner stationary phase films, increased carrier gas linear velocity, and faster temperature ramping. Our results indicated that fast GC analyses were comparable to conventional GC in peak resolution. A conventional transesterification method based on Lepage and Roy was simplified to a one-step method with the elimination of the neutralization and centrifugation steps. A robotics-amenable method was also developed, with lower methylation temperatures and in an open-tube format using multiple reagent additions. The simplified methods produced results that were quantitatively similar and with similar coefficients of variation as compared with the original Lepage and Roy method.

The regional Mediterranean Diet has been associated with lower risk of disease. We tested the health effects of the New Nordic Diet (NND), which is a gastronomically driven regional, organic, and environmentally friendly diet, in a carefully controlled but free-living setting. A total of 181 centrally obese men and women, with a mean (range) age of 42 y (20-66 y), body mass index (in kg/m(2)) of 30.2 (22.6-47.3), and waist circumference of 100 cm (80-138 cm) were randomly assigned to receive either the NND (high in fruit, vegetables, whole grains, and fish) or an average Danish diet (ADD) for 26 wk. Participants received cookbooks and all foods ad libitum and free of charge by using a shop model. The primary endpoint was the weight change analyzed by both completer and intention-to-treat analyses. A total of 147 subjects [81% (NND 81%; ADD 82%)] completed the intervention. A high dietary compliance was achieved, with significant differences in dietary intakes between groups. The mean (±SEM) weight change was -4.7 ± 0.5 kg for the NND compared with -1.5 ± 0.5 kg for the ADD (adjusted difference: -3.2 kg; 95% CI: -4.6, -1.8 kg; P < 0.001) for the completer analysis, and the difference was -3.0 kg (95% CI: -4.0, -2.1 kg) for the intention-to-treat analysis. The NND produced greater reductions in systolic blood pressure (adjusted difference: -5.1 mm Hg; 95% CI: -8.2, -2.1 mm Hg) and diastolic blood pressure (adjusted difference: -3.2 mm Hg; 95% CI: -5.7, -0.8 mm Hg) than did the ADD. An ad libitum NND produces weight loss and blood pressure reduction in centrally obese individuals. This trial was registered at www.clinicaltrials.gov as NCT01195610.

Background: Dietary docosahexaenoic acid (DHA) has triacylglycerol-lowering potential and undergoes in vivo retroconversion to eicosapentaenoic acid (EPA) in humans. Hormone replacement therapy (HRT) influences circulating lipid concentrations and fatty acid metabolism. DHA supplementation has not been studied in postmenopausal women. Objective: We studied the effects of supplementation with DHA (free of EPA) on the resulting elevation in EPA and on selected cardiovascular disease risk factors in postmenopausal women. Design: Women receiving (n = 18) and not receiving (n = 14) HRT completed a randomized, double-blind, placebo-controlled crossover trial with a DHA supplement (2.8 g DHA/d). A washout period of ≥ 6 wk divided the two 28-d intervention periods. Fasting blood samples were collected for analysis. Results: In all women, DHA supplementation was associated with significant changes (P < 0.05), including 20% lower serum triacylglycerol concentrations, 8% higher HDL-cholesterol concentrations, a 28% lower overall ratio of serum triacylglycerol to HDL cholesterol, and a 7% decrease in resting heart rate. DHA supplementation resulted in a 45% lower net increase (P = 0.02) in EPA and a 42% lower (P = 0.0028) estimated percentage retroconversion of DHA to EPA [ΔEPA/(ΔEPA + ΔDHA) × 100] in women receiving than in those not receiving HRT. Conclusion: With DHA supplementation, the accumulation of EPA in serum phospholipids is significantly attenuated in postmenopausal women receiving HRT compared with that in women not receiving HRT. DHA supplementation can also favorably influence selected cardiovascular disease risk factors in postmenopausal women.

During pregnancy, (n-3) PUFA are incorporated into fetal brain and retinal lipids. Docosahexaenoic acid [DHA, 22:6(n-3)], in particular, is required physiologically for optimal development and function of the central nervous system. Maternal intake of (n-3) PUFA must be sufficient to maintain maternal tissues stores and meet fetal accruement. Recommendations for pregnant women include an Acceptable Macronutrient Distribution Range (AMDR) of 0.6–1.2% of energy for (n-3) PUFA intake in the current Dietary Reference Intakes, and ≥300 mg/d of DHA suggested by the International Society for the Study of Fatty Acids and Lipids working group. The present study directly quantitated the (n-3) PUFA intake, including DHA, of pregnant, Canadian women (n = 20) in their 2nd and 3rd trimester. Fatty acid intakes were quantitated in triplicate by lipid extraction and GLC of 3-d duplicate food collections calibrated with an internal standard before homogenization. Total fat intakes were also estimated using dietary analysis software from simultaneous 3-d food records to corroborate biochemical analyses. The mean (n-3) PUFA intake was 0.57 ± 0.06% of energy, with 65% of the women below the AMDR. The mean DHA intake was 82 ± 33 mg/d, with 90% of the women consuming <300 mg/d. Nutritional education of pregnant women to ensure adequate intakes of (n-3) PUFA for optimal health of mother and child and the inclusion of DHA in prenatal vitamins may be pertinent.