Omega-3 Polyunsaturated Fatty Acid Supplementation for Reducing Muscle Soreness after Eccentric Exercise: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Purpose. This systematic review and meta-analysis was performed to determine the effectiveness of Omega-3 polyunsaturated fatty acid (n‐3 PUFA) supplement on muscle soreness after eccentric exercise. Methods. PubMed, EMBASE, CENTRAL, and ISI Web of Science were searched to identify randomized controlled trials (RCTs) that assessed the efficacy of n‐3 PUFA on muscle soreness after eccentric exercise. Mean difference (MD) and the associated 95% confidence interval (95% CI) were calculated by RevMan 5.3 to indicate delayed onset muscle soreness (DOMS) that measured two days after eccentric trainings. Subgroup analyses according to duration and daily dosage of n‐3 PUFA supplements before eccentric exercises were performed to determine whether these factors will influence the overall effect size. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach was used to evaluate the certainty of evidence. The protocol of this systematic review and meta-analysis was registered at PROSPERO (CRD42018085869). Results. 12 RCTs containing 145 subjects and 156 controls were included in this study. Meta-analysis revealed a significantly decreased DOMS (MD -0.93; 95% CI -1.44, -0.42; P=0.0004) in n‐3 PUFA supplement groups, while no significant differences in isometric muscle strength and range of motion (ROM) were detected. However, the pooled effect size for DOMS was lower than the minimal clinically important difference (MCID) of 1.4 on the 10-unit VAS, suggesting that the effect size of less muscle soreness with n‐3 PUFA supplements did not appear to be clinically relevant. Conclusion. There is low-quality evidence that n‐3 PUFA supplementation does not result in a clinically important reduction of muscle soreness after eccentric exercise. Isometric muscle soreness and range of motion were not improved by n‐3 PUFA supplementation either (low-quality evidence). To further elucidate the overall role of n‐3 PUFA on muscle damage in this area, large-scale RCTs are still needed.

PSI-18 Effects of supplementing polyunsaturated fatty acids during late gestation on performance of fall-calving cows

The objective was to determine the effects of supplementing calcium salts of PUFA or SFA + MUFA during late gestation on performance of fall-calving beef cows through calving. Mature, Simmental x Angus cows confirmed pregnant to a synchronized artificial insemination (AI) and fetal sexed were selected prior to the start of the experiment. At 200 d of gestation, cows (n = 96; BW = 603 ± 72 kg) were stratified by age, AI service sire, fetal sex and BW and allotted to 8 groups. Groups were randomly assigned to 1 of 2 treatments (4 groups per treatment): SFA + MUFA (0.155 kg of EnerGII per cow per day on a DM basis) and PUFA (0.08 kg of Strata and 0.08 kg of Prequel per cow per day on a DM basis). The SFA + MUFA supplement included palmitic and oleic acid. The PUFA supplement included eicosapentaenoic acid, docosahexaenoic acid, and linoleic acid. All cows grazed endophyte-infected tall fescue and were supplemented 2 kg DM per cow per d of soybean hulls for 78 d during late gestation in addition to their treatment supplement. Body condition score and BW were collected at trial initiation, during supplementation, before calving, and after calving. Pen was the experimental unit and BW, BCS, and calf BW were analyzed using the MIXED procedure of SAS. The BW and BCS at trial initiation, during supplementation, before calving, and after calving of the cows supplemented PUFA were not different (P ≥ 0.38) than the BW and BCS of cows supplemented SFA + MUFA. Calf birth BW from cows supplemented with PUFA were not different (P = 0.87) than calf birth BW from cows supplemented with SFA + MUFA. Supplementing cows PUFA during late gestation in fall-calving cows did not affect BW, BCS or calf birth BW.

Longitudinal associations between marine omega-3 supplement users and coronary heart disease in a UK population-based cohort

ObjectivesAssess the association between marine omega-3 polyunsaturated fatty acid (n-3 PUFA) intake from supplements, mainly cod liver oil, and coronary heart disease (CHD) mortality.DesignProspective cohort study, with three exposure measurements over 22 years.SettingNorfolk-based European Prospective Investigation into Cancer (EPIC-Norfolk, UK).Participants22 035 men and women from the general population, 39–79 years at recruitment.ExposureSupplement use was assessed in three questionnaires (1993–1998; 2002–2004; 2004–2011). Participants were grouped into non-supplement users (NSU), n-3 PUFA supplement users (SU+n3) and non–n-3 PUFA supplement users (SU-n3). Cox regression adjusted for time-point specific variables: age, smoking, prevalent illnesses, body mass index, alcohol consumption, physical activity and season and baseline assessments of sex, social class, education and dietary intake (7-day diet diary).Primary and secondary outcome measuresDuring a median of 19-year follow-up, 1562 CHD deaths were registered for 22 035 included participants.ResultsBaseline supplement use was not associated with CHD mortality, but baseline food and supplement intake of n-3 PUFA was inversely associated with CHD mortality after adjustment for fish consumption. Using time-varying covariate analysis, significant associations were observed for SU+n3 (HR: 0.74, 95% CI 0.66 to 0.84), but not for SU-n3 versus NSU. In further analyses, the association for SU+n3 persisted in those who did not take other supplements (HR: 0.83, 95% CI 0.71 to 0.97). Those who became SU+n3 over time or were consistent SU+n3 versus consistent NSU had a lower hazard of CHD mortality; no association with CHD was observed in those who stopped using n-3 PUFA-containing supplements.ConclusionsRecent use of n-3 PUFA supplements was associated with a lower hazard of CHD mortality in this general population with low fish consumption. Residual confounding cannot be excluded, but the findings observed may be explained by postulated biological mechanisms and the results were specific to SU+n3.

Oxidation levels of North American over-the-countern-3 (omega-3) supplements and the influence of supplement formulation and delivery form on evaluating oxidative safety

The aim of the present study was to evaluate the oxidation status of North Americann-3 (omega-3) PUFA nutritional supplements commercially available in Canada and evaluate the influence of product formulation and delivery form on oxidative safety. A total of 171 North American over-the-countern-3 PUFA nutritional supplements were analysed for oxidation safety. Primary and secondary oxidation and total oxidation (TOTOX) were determined using the American Oil Chemists’ Society (AOCS) procedures. Comparisons between supplements’ final forms, oil source andn-3 PUFA concentration quartiles, as measures of product formulations and delivery forms, were compared using ANOVA. Of the products successfully tested, 50 % exceeded the voluntary recommended levels for markers of oxidation. Another 18 % of products were approaching the limits with 1–3 years before expiration. Encapsulated products without flavour additives had significantly lower secondary and TOTOX levels than bulk oils and flavoured products (P < 0·05). Children's products had significantly higher primary, secondary and TOTOX levels compared with all other products (P < 0·05). Markers of oxidation did not differ between oil sources (P > 0·05), with the exception of krill oil products having higher secondary oxidation levels than plant-based products (P > 0·05). Markers of oxidation did not differ betweenn-3 PUFA supplement concentration quartiles. Consumers may be at risk of exposure to higher levels of oxidative products. New regulatory mandates need to be introduced to ensure that alln-3 PUFA products, used as nutritional supplements, regardless of their formulation or delivery form, can be tested for oxidative safety and compliance.

Omega-3 Fatty Acids and Depression: Scientific Evidence and Biological Mechanisms

The changing of omega-6/omega-3 polyunsaturated fatty acids (PUFA) in the food supply of Western societies occurred over the last 150 years is thought to promote the pathogenesis of many inflammatory-related diseases, including depressive disorders. Several epidemiological studies reported a significant inverse correlation between intake of oily fish and depression or bipolar disorders. Studies conducted specifically on the association between omega-3 intake and depression reported contrasting results, suggesting that the preventive role of omega-3 PUFA may depend also on other factors, such as overall diet quality and the social environment. Accordingly, tertiary prevention with omega-3 PUFA supplement in depressed patients has reached greater effectiveness during the last recent years, although definitive statements on their use in depression therapy cannot be yet freely asserted. Among the biological properties of omega-3 PUFA, their anti-inflammatory effects and their important role on the structural changing of the brain should be taken into account to better understand the possible pathway through which they can be effective both in preventing or treating depression. However, the problem of how to correct the inadequate supply of omega-3 PUFA in the Westernized countries’ diet is a priority in order to set food and health policies and also dietary recommendations for individuals and population groups.

Dietary supplementation with fish gelatine modifies nutrient intake and leads to sex-dependent responses in TAG and C-reactive protein levels of insulin-resistant subjects

Previous studies have shown that fish protein, as well as marine n-3 PUFA, may have beneficial effects on cardiovascular risk profile. The objectives of this study were to investigate the combined effects of fish gelatine (FG) and n-3 PUFA supplementation on (1) energy intake and body weight, (2) lipid profile and (3) inflammatory and CVD markers in free-living insulin-resistant males and females. Subjects were asked to consume, in a crossover study design with two experimental periods of 8 weeks each, an n-3 PUFA supplement and n-3 PUFA supplement plus FG (n-3 PUFA + FG). n-3 PUFA + FG led to an increase in protein intake and a decrease in carbohydrate intake compared with n-3 PUFA (P < 0·02) in males and females. Sex–treatment interactions were observed for TAG (P = 0·03) and highly sensitive C-reactive protein (hsCRP) (P = 0·001) levels. In females, n-3 PUFA reduced plasma TAG by 8 % and n-3 PUFA + FG by 23 %, whereas in males, n-3 PUFA reduced plasma TAG by 25 % and n-3 PUFA + FG by 11 %. n-3 PUFA increased serum hsCRP by 13 % and n-3 PUFA + FG strongly reduced hsCRP by 40 % in males, whereas in females, n-3 PUFA reduced serum hsCRP by 6 % and n-3 PUFA + FG increased hsCRP by 20 %. In conclusion, supplementation with FG may enhance the lipid-lowering effect of marine n-3 PUFA in females and beneficially counteract the effect of n-3 PUFA on serum hsCRP in males. Further studies are needed to identify the sex-dependent mechanisms responsible for the divergent effects of FG on TAG and hsCRP levels in females and males, respectively.

Food Products as Vehicles For n-3 Fatty Acid Supplementation

Purpose: An n-3 polyunsaturated fatty acid (PUFA) supplement was incorporated into three food products previously determined to be preferred by cancer patients, and overall acceptability of these foods was evaluated. Methods: Preliminary testing was performed; an internal panel determined initial acceptability of foods with the supplement added. Taste panel evaluations were held at the Cross Cancer Institute in Edmonton, Alberta. Each participant completed a questionnaire rating aroma, flavour, and overall acceptance on a seven-point hedonic scale (1 = dislike extremely, 7 = like extremely), as well as ability to consume each food daily. Results: Foods were well-liked by patients and non-patients. Mean ± standard deviation acceptance scores for the three foods were pasta sauce 5.9 ± 0.94 (n = 90), oatmeal 6.1 ± 0.88 (n = 79), and smoothie 5.9 ± 1.12 (n = 126). Overall, 94% of patients and non-patients gave tomato pasta sauce, oatmeal, and the smoothie an acceptance score of at least 5. Conclusions: The supplement was incorporated successfully into three foods, which were highly accepted by patients with cancer. Further research should focus on incorporating the supplement into flavoured or sweet foods, as these appear most effective. Microencapsulated fish oil in food products may be used as an alternative to fish oil capsules for delivering n-3 PUFA in clinical trials.