Oily Fish and Omega-3s Across the Life Stages: A Focus on Intakes and Future Directions

Essential Fatty Acids along the Women’s Life Cycle and Promotion of a Well-balanced Metabolism

Abstract:

Linoleic acid (ω-6 LA) and α-linolenic acid (ω-3 ALA) are essential fatty acids (EFA) for human beings. They must be consumed through diet and then extensively metabolized, a process that plays a fundamental role in health and eventually in disease prevention. Given the numerous changes depending on age and sex, EFA metabolic adaptations require further investigations along the women’s life cycle, from onset to decline of the reproductive age. Thus, this review explains women’s life cycle stages and their involvement in diet intake, digestion and absorption, the role of microbiota, metabolism, bioavailability, and EFA fate and major metabolites. This knowledge is crucial to promoting lipid homeostasis according to female physiology through well-directed health strategies. Concerning this, the promotion of breastfeeding, nutrition, and physical activity is cardinal to counteract ALA deficiency, LA/ALA imbalance, and the release of unhealthy derivatives. These perturbations arise after menopause that compromise both lipogenic and lipolytic pathways. The close interplay of diet, age, female organism, and microbiota also plays a central role in regulating lipid metabolism. Consequently, future studies are encouraged to propose efficient interventions for each stage of women's cycle. In this sense, plant-derived foods and products are promising to be included in women’s nutrition to improve EFA metabolism.

Improving Undernutrition with Microalgae

Undernutrition is an important global health problem, especially in children and older adults. Both reversal of maternal and child undernutrition and heathy ageing have become United Nations-supported global initiatives, leading to increased attention to nutritional interventions targeting undernutrition. One feasible option is microalgae, the precursor of all terrestrial plants. Most commercially farmed microalgae are photosynthetic single-celled organisms producing organic carbon compounds and oxygen. This review will discuss commercial opportunities to grow microalgae. Microalgae produce lipids (including omega-3 fatty acids), proteins, carbohydrates, pigments and micronutrients and so can provide a suitable and underutilised alternative for addressing undernutrition. The health benefits of nutrients derived from microalgae have been identified, and thus they are suitable candidates for addressing nutritional issues globally. This review will discuss the potential benefits of microalgae-derived nutrients and opportunities for microalgae to be converted into food products. The advantages of microalgae cultivation include that it does not need arable land or pesticides. Additionally, most species of microalgae are still unexplored, presenting options for further development. Further, the usefulness of microalgae for other purposes such as bioremediation and biofuels will increase the knowledge of these microorganisms, allowing the development of more efficient production of these microalgae as nutritional interventions.

Potential causal link between dietary intake and epilepsy: a bidirectional and multivariable Mendelian randomization study

Background

Epilepsy is a common neurological disease, and dietary intake has been suggested as a potential modifiable risk factor. However, the causality of associations between dietary intake and epilepsy remains uncertain. This study aimed to investigate the potential causal relationships between various dietary intakes and epilepsy using Mendelian randomization (MR) analysis.

Methods

A two-sample MR approach was employed, utilizing genetic variants associated with dietary factors as instrumental variables (IVs). Genome-Wide Association Study (GWAS) summary data on dietary intakes were obtained from the UK Biobank, while data on epilepsy were sourced from the European Bioinformatics Institute. The number of genetic variants used as IVs varied for each dietary factor. Inverse-variance weighted (IVW), weighted median, MR-Egger, and Bayesian weighted MR (BWMR) methods were used to assess causality. Multivariable MR (MVMR) was performed, adjusting for potential confounders. Sensitivity analyses were conducted to evaluate the robustness of the findings.

Results

The study identified a significant inverse association between non-oily fish intake and epilepsy risk (OR = 0.281, 95% CI: 0.099-0.801, p = 0.018) using the IVW method. This finding was corroborated by the BWMR analysis (OR = 0.277, 95% CI: 0.094-0.814, p = 0.020). The MVMR analysis further confirmed the protective effect of non-oily fish intake on epilepsy risk after adjusting for potential confounders. In the reverse MR analysis, epilepsy was associated with reduced water intake (OR = 0.989, 95% CI: 0.980-0.997, p = 0.011).

Conclusion

The present MR study provides evidence of a causal, protective relationship between non-oily fish intake and reduced epilepsy risk. Additionally, the findings suggest that epilepsy may influence water intake patterns. These results contribute to our understanding of the role of dietary factors in epilepsy and may inform dietary recommendations for the management and prevention of this condition.

Evaluating the Stability and Digestibility of Long-Chain Omega-3 Algal Oil Nanoemulsions Prepared with Lecithin and Tween 40 Emulsifiers Using an In Vitro Digestion Model

The health benefits of long-chain omega-3 polyunsaturated fatty acid (LCn-3PUFA) intake have been well documented. However, currently, the consumption of oily fish (the richest dietary source of LCn-3PUFA) in the UK is far below the recommended level, and the low digestibility of LCn-3PUFA bulk oil-based supplements from triglyceride-based sources significantly impacts their bioavailability. LCn-3PUFA-rich microalgal oil offers a potential alternative for populations who do not consume oily fish, and nanoemulsions have the potential to increase LCn-3PUFA digestibility and bioavailability. The aims of this study were to produce stable algal oil-in-water nanoemulsions with ultrasonic technology to increase DHA digestibility, measured using an in vitro digestion model. A nanoemulsion of LCn-3PUFA algal oil was developed with 6% w/w emulsifiers: lecithin (LE) or an equal ratio of Tween 40 (3%) and lecithin (LTN) (3%), 50% w/w, algal oil and 44% w/w water using rotor-stator and ultrasound homogenization. The in vitro digestion experiments were conducted with a gastric and duodenal digestion model. The results showed the creation of nanoemulsions of LCn-3PUFA algal oils offers potentially significant increases in the bioavailability of DHA in the human body. The increase in digestibility can be attributed to the smaller particle size of the nanoemulsions, which allows for higher absorption in the digestive system. This showed that the creation of nanoemulsions of LCn-3PUFA algal oils offers a potentially significant increase in the bioavailability of DHA in the human body. The LE and LTN nanoemulsions had average droplet sizes of 0.340 ± 0.00 µm and 0.267 ± 0.00 µm, respectively, but the algal oil mix (sample created with same the components as the LTN nanoemulsion, hand mixed, not processed by rotor-stator and ultrasound homogenization) had an average droplet size of 73.6 ± 6.98 µm. The LTN algal oil nanoemulsion was stable in the gastric and duodenal phases without detectable destabilization; however, the LE nanoemulsion showed signs of oil phase separation in the gastric phase. Under the same conditions, the amount of DHA digested from the LTN nanoemulsion was 47.34 ± 3.14 mg/g, compared to 16.53 ± 0.45 mg/g from the algal oil mix, showing DHA digestibility from the LTN nanoemulsion was 2.86 times higher. The findings of this study contribute to the insight of in vitro DHA digestion under different conditions. The stability of the LTN nanoemulsion throughout digestion suggests it could be a promising delivery system for LCn-3PUFAs, such as DHA, in various food and pharmaceutical applications.

Optimal omegas - barriers and novel methods to narrow omega-3 gaps. A narrative review

Dietary intakes of omega-3 long chain polyunsaturated fatty acids (O3LC-PUFAs) such as eicosapentaenoic and docosahexaenoic acid are central to development and health across the life course. O3LC-PUFAs have been linked to neurological development, maternal and child health and the etiology of certain non-communicable diseases including age-related cognitive decline, cardiovascular disease, and diabetes. However, dietary inadequacies exist in the United Kingdom and on a wider global scale. One predominant dietary source of O3LC-PUFAs is fish and fish oils. However, growing concerns about overfishing, oceanic contaminants such as dioxins and microplastics and the trend towards plant-based diets appear to be acting as cumulative barriers to O3LC-PUFAs from these food sources. Microalgae are an alternative provider of O3LC-PUFA-rich oils. The delivery of these into food systems is gaining interest. The present narrative review aims to discuss the present barriers to obtaining suitable levels of O3LC-PUFAs for health and wellbeing. It then discusses potential ways forward focusing on innovative delivery methods to utilize O3LC-PUFA-rich oils including the use of fortification strategies, bioengineered plants, microencapsulation, and microalgae.

Inter-relationships of obesity-related eating behavior with depression and anxiety among adults during the COVID-19 pandemic: A network analysis

The COVID-19 pandemic has significantly impacted individuals' mental health, resulting in a higher incidence of depression, anxiety, and changes in eating behaviors. The objective of this study is to examine the inter-relationships among obesity-related eating behavior, depression, and anxiety in adults during the COVID-19 pandemic, utilizing a network analysis method. We conducted a cross-sectional survey among a representative sample of 9091 adults between July 10 and September 15, 2021. Participants completed self-report measures to assess obesity-related eating behavior and symptoms of depression and anxiety. Network analysis was employed to investigate the inter-relationships among these variables. The network analysis revealed that item 2 (i.e., Do not feel satisfied unless I eat until full) exhibited the highest node strength within the network, followed by item 5 (i.e., Like oily foods). In addition, positive correlations were found between the severity of depression and anxiety and most of the obesity-related eating behavior items. These findings offer valuable insights into the interplay between obesity-related eating behavior, depression, and anxiety during the COVID-19 pandemic, underscoring the significance of considering these factors in comprehending and addressing mental health and well-being in adults. Further research is warranted to explore potential interventions and treatment approaches that specifically target the identified relationships.

Analysis of Fish-Consumption Benefits and Safety Knowledge in a Population-Based Sample of Polish Adolescents

Inadequate fish consumption is common and may result from multiple reasons, especially in adolescents who are a population at particular risk of the negative consequences of not consuming the recommended amounts of fish. The aim of the study was to analyze the knowledge about fish-consumption benefits and safety in a population-based sample of Polish adolescents. The stratified random sampling was conducted within two stages: sampling of counties from all voivodeships in Poland (being the basic administrative units of Poland) and inviting secondary schools from the drawn counties to obtain a sample representative of all regions of Poland. The Computer-Assisted Web Interview (CAWI) method was applied to gather the data within the study, and a questionnaire concerning knowledge about fish-consumption benefits and safety with 20 true-false statements was applied. Among 1289 participants, the statement with the highest share of correct answers concerned fish being a source of protein (78.9%) and fish-derived fats being health promoting (77.0%). The statement receiving the least correct answers concerned the type of fatty acids found in fish (7.6%) and the risk of polychlorinated biphenyls (PCBs) in fish (20.5%). Participants who were female, older than 18, underweight, living in an urban environment, from a region far away from the sea and from comprehensive schools provided a higher share of correct answers than other subgroups (p < 0.05). Knowledge concerning fish-consumption benefits and safety among Polish adolescents is in many cases inadequate; thus, nutritional education is needed, especially among younger adolescents, those attending vocational schools, males and those living in a rural environment.

Isocaloric Substitution of Plant-Based Protein for Animal-Based Protein and Cardiometabolic Risk Factors in a Multiethnic Asian Population

BACKGROUND

Evidence is accumulating that intake of animal-based and plant-based proteins has different effects on cardiometabolic health, but less is known about the health effect of isocaloric substitution of animal-based and plant-based proteins. Data from Asian populations are limited.

OBJECTIVES

This study aimed to evaluate the effects of isocaloric substitution of total plant-based proteins for total and various animal-based protein food groups and to evaluate the effects of substituting protein from legumes and pulses for various animal-based protein food groups on cardiovascular disease (CVD) risk factors and predicted 10-y CVD risk.

METHODS

We conducted a cross-sectional analysis using data collected from 9211 Singapore residents (aged 21-75 y) from the Singapore Multi-Ethnic Cohort. Data on sociodemographic and lifestyle factors were collected using questionnaires. Dietary intakes were assessed using a validated FFQ. BMI, waist circumference, and blood pressure were measured during a physical examination, and blood samples were collected to measure lipid profiles. Associations were assessed by substitution models using a multiple linear regression analysis.

RESULTS

Isocaloric substitution of total plant-based proteins for total and all specific animal-based protein food groups were associated with lower BMI (β: -0.30; 95% CI: -0.38, -0.22), waist circumference (β: -0.85; 95% CI: -1.04, -0.66), and LDL cholesterol concentrations (β: -0.06; 95% CI: -0.08, -0.05) (P < 0.0056). Replacement of processed meat and processed seafood proteins with total plant-based proteins was associated with improvement in most CVD risk factors and predicted 10-y CVD risk. Replacement of oily fish with legume proteins was associated with lower HDL cholesterol and higher TG concentrations.

CONCLUSIONS

The substitution of plant-based proteins for animal-based proteins, especially from processed meat and processed seafood, was inversely associated with the established CVD risk factors such as BMI, waist circumference, and lipid concentrations and predicted 10-y CVD risk. These findings warrant further investigation in independent studies in other Asian populations.

The Influence of APOE Genotype, DHA, and Flavanol Intervention on Brain DHA and Lipidomics Profile in Aged Transgenic Mice

The apolipoprotein E4 (APOE4) genotype is predictive of Alzheimer's disease (AD). The brain is highly enriched with the omega-3 polyunsaturated fatty acid (n3-PUFA), docosahexaenoic acid (DHA). DHA's metabolism is defective in APOE4 carriers. Flavanol intake can play a role in modulating DHA levels. However, the impact of flavanol co-supplementation with fish oil on brain DHA uptake, status and partitioning, and according to APOE genotype is currently unknown. Here, using a humanised APOE3 and APOE4 targeted replacement transgenic mouse model, the interactive influence of cocoa flavanols (FLAV) and APOE genotype on the blood and subcortical brain PUFA status following the supplementation of a high fat (HF) enriched with DHA from fish oil (FO) was investigated. DHA levels increased in the blood (p < 0.001) and brain (p = 0.001) following supplementation. Compared to APOE3, a higher red blood cell (RBC) DHA (p < 0.001) was evident in APOE4 mice following FO and FLAV supplementation. Although FO did not increase the percentage of brain DHA in APOE4, a 17.1% (p < 0.05) and 20.0% (p < 0.001) higher DHA level in the phosphatidylcholine (PC) fraction in the HF FO and HF FO FLAV groups, and a 14.5% (p < 0.05) higher DHA level in the phosphatidylethanolamine (PE) fraction in the HF FO FLAV group was evident in these animals relative to the HF controls. The addition of FLAV (+/- FO) did not significantly increase the percentage of brain DHA in the group as a whole. However, a higher brain: RBC DHA ratio was evident in APOE3 only (p < 0.05) for HF FLAV versus HF. In conclusion, our data shows only modest effects of FLAV on the brain DHA status, which is limited to APOE3.

Destabilization of Aβ fibrils by omega-3 polyunsaturated fatty acids: a molecular dynamics study

The senile plaques of neurotoxic aggregates of Aβ protein, deposited extraneuronally, mark the pathological hallmark of Alzheimer's disease (AD). The natural compounds such as omega-3 (ω-3) polyunsaturated fatty acids (PUFAs), which can access blood-brain barrier, are believed to be potential disruptors of preformed Aβ fibrils to cure AD with unknown mechanism. Herein, we present the destabilization potential of three ω-3 PUFAs, viz. Eicosapentaenoic acid (EPA), Docosahexaenoic acid (HXA), and α-linolenic acid (LNL) by molecular dynamics simulation. After an initial testing of 300 ns, EPA and HXA have been considered further for extended production run time, 500 ns. The increased value of root mean square deviation (RMSD), radius of gyration, and solvent-accessible surface area (SASA), the reduced number of H-bonds and β-sheet content, and disruption of salt bridges and hydrophobic contacts establish the binding of these ligands to Aβ fibril leading to destabilization. The polar head was found to interact with positively charged lysine (K28) residue in the fibril. However, the hydrophobicity of the long aliphatic tail competes with the intrinsic hydrophobic interactions of Aβ fibril. This amphiphilic nature of EPA and HXA led to the breaking of inherent hydrophobic contacts and formation of new bonds between the tail of PUFA and hydrophobic residues of Aβ fibril, leading to the destabilization of fibril. The Molecular Mechanics Poisson-Boltzmann Surface Area (MM-PBSA) results explain the binding of EPA and HXA to Aβ fibril by interacting with different residues. The destabilization potential of EPA and HXA establishes them as promising drug leads to cure AD, and encourages prospecting of other fatty acids for therapeutic intervention in AD.Communicated by Ramaswamy H. Sarma.

PGC-1α activity and mitochondrial dysfunction in preterm infants

Extremely low gestational age neonates (ELGANs) are born in a relatively hyperoxic environment with weak antioxidant defenses, placing them at high risk for mitochondrial dysfunction affecting multiple organ systems including the nervous, respiratory, ocular, and gastrointestinal systems. The brain and lungs are highly affected by mitochondrial dysfunction and dysregulation in the neonate, causing white matter injury (WMI) and bronchopulmonary dysplasia (BPD), respectively. Adequate mitochondrial function is important in providing sufficient energy for organ development as it relates to alveolarization and axonal myelination and decreasing oxidative stress via reactive oxygen species (ROS) and reactive nitrogen species (RNS) detoxification. Peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) is a master regulator of mitochondrial biogenesis and function. Since mitochondrial dysfunction is at the root of WMI and BPD pathobiology, exploring therapies that can regulate PGC-1α activity may be beneficial. This review article describes several promising therapeutic agents that can mitigate mitochondrial dysfunction through direct and indirect activation and upregulation of the PGC-1α pathway. Metformin, resveratrol, omega 3 fatty acids, montelukast, L-citrulline, and adiponectin are promising candidates that require further pre-clinical and clinical studies to understand their efficacy in decreasing the burden of disease from WMI and BPD in preterm infants.

Relevance of ω-6 GLA Added to ω-3 PUFAs Supplements for ADHD: A Narrative Review

The use of polyunsaturated fatty acids in Attention-Deficit/Hyperactivity Disorder (ADHD) and developmental disorders has been gaining interest with preparations containing different dosages and combinations. Gamma-linolenic acid (GLA) is an ω-6 fatty acid of emerging interest with potential roles as an adjuvant anti-inflammatory agent that could be used with ω-3 PUFAs in the treatment of ADHD and associated symptoms. A narrative review was undertaken to examine the potential role(s) of the ω-6 fatty acid GLA. PubMed, Google Scholar, and Scopus were searched to examine the potential role(s) of the ω-6 fatty acid GLA as (1) an antioxidant and anti-inflammatory agent, (2) a synergistic nutrient when combined with ω-3 PUFAs, and (3) a potential etiological factor in ADHD and its treatment. The results show that GLA exerts anti-inflammatory effects by increasing dihomo-gamma-linolenic acid in immune cells. ω-3 PUFAs, such as EPA and DHA, are often co-administered with GLA because these ω-3 PUFAs may prevent the accumulation of serum arachidonic acid in response to GLA administration without limiting the storage of DGLA in immune cells. The administration of ω-3 PUFAs alone might not be sufficient to effectively treat patients with ADHD and developmental disorders. Overall studies point towards a combination of EPA and DHA with GLA in a 9:3:1 ratio appearing to be associated with ADHD symptom improvement. A combination of PUFAs may lead to better outcomes.

Genetically Predicted Circulating Omega-3 Fatty Acids Levels Are Causally Associated With Increased Risk for Systemic Lupus Erythematosus

Background

Accumulating evidence has demonstrated the associations of omega-3 or omega-6 polyunsaturated fatty acids (PUFAs) with the disease activity and inflammatory mediators of systemic lupus erythematosus (SLE), but the evidence of causal links of omega-3 or omega-6 PUFAs on the risk for SLE remains inconclusive.

Objectives

This study was conducted to evaluate the causal relationships between omega-3/omega-6 PUFAs and SLE by performing the Mendelian randomization (MR) analysis.

Methods

Genome-wide significant single-nucleotide polymorphisms (SNPs) were obtained from genome-wide association studies (GWASs) of circulating omega-3/omega-6 levels (n = up to 13,544) and GWAS meta-analyses of SLE (n = 14,267), respectively. The bidirectional two-sample MR (TSMR) analysis was conducted to infer the causality.

Results

The inverse-variance weighted (IVW) method revealed that genetically determined per SD increase in omega-3 levels were causally associated with an increased risk for SLE (odds ratios [ORs] = 1.49, 95% CI: 1.07, 2.08, p = 0.021), but no causal effect of omega-6 on the risk SLE was observed (IVW OR = 1.06, 95% CI: 0.72, 1.57, p = 0.759). In addition, there were no significantly causal associations in genetic predisposition to SLE with the changes of omega-3 and omega-6 levels, respectively (IVW beta for omega-3: 0.007, 95% CI: −0.006, 0.022, p = 0.299; IVW beta for omega-6: −0.008, 95% CI: −0.023, 0.006, p = 0.255).

Conclusion

The present study revealed the possible causal role of omega-3 on increasing the risk for SLE, it could be the potential implications for dietary recommendations.

Opportunities for Qualitative Analysis of Social Media Platforms in Dietetic Research and Practice

To date, most qualitative knowledge about individual eating patterns and the food environment has been derived from traditional data collection methods, such as interviews, focus groups, and observations. However, there currently exists a large source of nutrition-related data in social media discussions that have the potential to provide opportunities to improve dietetic research and practice. Qualitative social media discussion analysis offers a new tool for dietetic researchers and practitioners to gather insights into how the public discusses various nutrition-related topics. We first consider how social media discussion data come with significant advantages including low-cost access to timely ways to gather insights from the public, while also cautioning that social media data have limitations (e.g., difficulty verifying demographic information). We then outline 3 types of social media discussion platforms in particular: (i) online news article comment sections, (ii) food and nutrition blogs, and (iii) discussion forums. We discuss how each different type of social media offers unique insights and provide a specific example from our own research using each platform. We contend that social media discussions can contribute positively to dietetic research and practice.

Changes in plasma fatty acids and related biomarkers during transition to an exclusively plant- and fish-based diet in healthy adults

OBJECTIVE

The aim of this study was to examine the time scale of plasma fatty acid changes during transition to an exclusively plant- and fish-based diet in healthy individuals and determine whether there are associated alterations in arachidonic acid (ARA)-derived inflammatory mediators, estimated stearoyl coenzyme A desaturase (SCD) activity, and blood pressure.

METHODS

In pursuit of a religious fast, 36 adults abstained  from eating poultry, meat, dairy products, and eggs, while increasing fish intake for 6 wk. Participants were assessed 1 wk before (W0) and 1 (W1) and 6 (W6) weeks after the diet change.

RESULTS

By W6, fasting plasma long-chain ω-3 polyunsaturated fatty acids (ω-3 LC-PUFAs); docosahexaenoic (DHA) and eicosapentaenoic (EPA) had increased (+67% and +73%, respectively; P ≤ 0.001), with early rise of DHA (+22%), but not EPA at W1.The ω-3 index (sum of DHA and EPA as a percent of total fatty acids) increased from 2.1% to 3.4%. ARA decreased progressively (W1, -9%; W6, -16%; P < 0.001). ARA precursors γ-linolenic and dihomo-γ-linolenic acids also decreased, without changes in the ARA-derived mediators prostaglandin-E2 and leukotriene-B4. Myristic acid decreased at W1 (-37%) and W6 (-40%). There was no consistent change in SCD indices. At W6, systolic and diastolic blood pressure had declined by 8 and 5 mm Hg, respectively (P ≤ 0.013).

CONCLUSIONS

Shifting to a plant- and fish-based diet produces rapid and sustained increases in ω-3 LC-PUFAs and decreases the ω-6 PUFA ARA and its precursors, consistent with a cardio-protective profile. The rapid response suggests that these biomarkers may be useful for assessment of diet interventions.