The effect of oral omega-3 polyunsaturated fatty acid supplementation on muscle maintenance and quality of life in patients with cancer: A systematic review and meta-analysis

The efficacy of omega-3 fatty acids (O3FAs) as a complementary in colorectal cancer patients: A systematic review and meta-analysis

BACKGROUND & AIMS

Colorectal cancer (CRC) is the third most common malignancy in developed countries. Therefore, omega-3 fatty acids (O3FAs) have been suggested as a beneficial complementary treatment due to their ability to regulate inflammatory responses and improve nutrition levels.This study aimed to evaluate the effects of O3FAs as a complementary treatment for inflammation, nutrition levels, post-operative infectious complications, and enhancement of recovery in CRC patients.

METHODS

The literature search was carried out through three databases. The outcomes of interest were assessed by measuring pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) and CRP levels, serum albumin levels for nutrition assessment, post-operative infectious complications, and length of stay for recovery evaluation. Quality appraisal and meta-analysis were performed using RoB 2.0 and RevMan 5.4, respectively.

RESULTS

The result showed that O3FAs significantly reduced IL-6, CRP, and TNF-α, but did not affect IL-1β. Furthermore, the variable slightly increased serum albumin levels and the supplementation led to a decrease in post-operative infectious complications and shortened hospital stays.

CONCLUSION

O3FAs as a complementary treatment provided advantages for CRC patients, Further clinical trials and experiments should also be made emphasizing the impact and clinical implementation of O3FA in the nutritional status of CRC patients.

Expert consensus report on lipid mediators: Role in resolution of inflammation and muscle preservation

This meeting report presents a consensus on the biological aspects of lipid emulsions in parenteral nutrition, emphasizing the unanimous support for the integration of lipid emulsions, particularly those containing fish oil, owing to their many potential benefits beyond caloric provision. Lipid emulsions have evolved from simple energy sources to complex formulations designed to improve safety profiles and offer therapeutic benefits. The consensus highlights the critical role of omega-3 polyunsaturated fatty acids (PUFAs), notably eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), found in fish oil and other marine oils, for their anti-inflammatory properties, muscle mass preservation, and as precursors to the specialized pro-resolving mediators (SPMs). SPMs play a significant role in immune modulation, tissue repair, and the active resolution of inflammation without impairing host defense mechanisms. The panel's agreement underscores the importance of incorporating fish oil within clinical practices to facilitate recovery in conditions like surgery, critical illness, or immobility, while cautioning against therapies that might disrupt natural inflammation resolution processes. This consensus not only reaffirms the role of specific lipid components in enhancing patient outcomes, but also suggests a shift towards nutrition-based therapeutic strategies in clinical settings, advocating for the proactive evidence-based use of lipid emulsions enriched with omega-3 PUFAs. Furthermore, we should seek to apply our knowledge concerning DHA, EPA, and their SPM derivatives, to produce more informative randomized controlled trial protocols, thus allowing more authoritative clinical recommendations.

Advances in sarcopenia: mechanisms, therapeutic targets, and intervention strategies

Sarcopenia is a multifactorial condition characterized by loss of muscle mass. It poses significant health risks in older adults worldwide. Both pharmacological and non-pharmacological approaches are reported to address this disease. Certain dietary patterns, such as adequate energy intake and essential amino acids, have shown positive outcomes in preserving muscle function. Various medications, including myostatin inhibitors, growth hormones, and activin type II receptor inhibitors, have been evaluated for their effectiveness in managing sarcopenia. However, it is important to consider the variable efficacy and potential side effects associated with these treatments. There are currently no drugs approved by the Food and Drug Administration for sarcopenia. The ongoing research aims to develop more effective strategies in the future. Our review of research on disease mechanisms and drug development will be a valuable contribution to future research endeavors.

Long-chain n -3 polyunsaturated fatty acids for the management of age- and disease-related declines in skeletal muscle mass, strength and physical function

PURPOSE OF REVIEW

This review uses the hierarchy of evidence as a framework to critically evaluate the effect of long chain n -3 polyunsaturated fatty acid (LC n -3 PUFA) ingestion alone, or as an adjunctive intervention to resistance training, on muscle health-related outcomes in healthy and clinical older adult populations.

RECENT FINDINGS

Systematic reviews and meta-analyses of randomized controlled trials consistently report small, but clinically-relevant, effects of LC n -3 PUFA ingestion on strength outcomes, whereas mixed findings have been reported regarding changes in muscle mass and physical function. Cohort studies indicate an association between higher dietary LC n -3 PUFA intake and reduced likelihood of a sarcopenia diagnosis. Acute metabolic studies provide limited evidence for an effect of LC n -3 PUFA ingestion alone, or in combination with resistance training, on free-living integrated rates of MPS, static markers of muscle protein breakdown, or satellite cell activation in healthy older adults.

SUMMARY

Recent data supports the efficacy of LCn-3 PUFA ingestion to facilitate small, but clinically relevant, improvements in muscle strength in healthy and clinical older adult populations. The mechanism(s) that underpin the action of LC n -3 PUFA in promoting strength outcomes remain unknown, but likely relate to neuromuscular function.

Association between dietary antioxidant and fatty acids and low muscle mass in obese and non-obese community-dwelling older adults: An NHANES analysis

Sarcopenia increases disability, hospital stays, readmissions, and mortality in older adults. Antioxidative nutrients and fatty acids consumption may help maintain muscle mass by reducing oxidative stress. This study aims to assess the association between antioxidant and fatty acid intake and low muscle mass in community-dwelling older people. This retrospective analysis used data from the National Health and Nutrition Examination Survey from 1999 to 2004. Participants ≥ 60 years with information on muscle mass measured by Dual energy X-ray absorptiometry (DXA) were included. Appendicular skeletal muscle mass was assessed. Associations between antioxidants and fatty acids intake, and low muscle mass were evaluated using logistic regressions. 3648 (1748 men and 1900 women) were included. The prevalence of low muscle mass was 41% and 26% among men and women ≥ 75 years, and 45.2% and 28.4% among obese men and women. In obese males, a natural-log-unit increase of vitamin A (aOR = 0.806, 95% CI: 0.652-0.996), vitamin C (aOR = 0.878, 95% CI: 0.779-0.990), selenium intake (aOR = 0.716, 95% CI: 0.517-0.993), and higher saturated fatty acids (aOR = 0.956, 95% CI: 0.915-0.998) and monounsaturated fatty acids (aOR = 0.959, 95% CI: 0.925-0.994) intake were associated with decreased odds for low muscle mass. Among obese females, a natural-log-unit increase of vitamin E (P = .036), vitamin B12 (P = .014), total folate (P = .015), zinc (P = .005), and selenium intake (P = .018) were associated with increased odds of low muscle mass, whereas higher saturated fatty acids (P < .001), monounsaturated fatty acids (P = .001), and polyunsaturated fatty acids intake (P = .006) were associated with decreased odds for low muscle mass. Antioxidants (vitamin A, C, E, B6, B12, total folate, zinc, magnesium, selenium) intake does not consistently relate to low muscle mass across age and sex. Higher intake of saturated, monounsaturated, and polyunsaturated fatty acids are independently associated with reduced likelihood of low muscle mass in both obese older men and women.

Optimizing clinical nutrition research: the role of adaptive and pragmatic trials

Evidence-based nutritional recommendations address the health impact of suboptimal nutritional status. Efficacy randomized controlled trials (RCTs) have traditionally been the preferred method for determining the effects of nutritional interventions on health outcomes. Nevertheless, obtaining a holistic understanding of intervention efficacy and effectiveness in real-world settings is stymied by inherent constraints of efficacy RCTs. These limitations are further compounded by the complexity of nutritional interventions and the intricacies of the clinical context. Herein, we explore the advantages and limitations of alternative study designs (e.g., adaptive and pragmatic trials), which can be incorporated into RCTs to optimize the efficacy or effectiveness of interventions in clinical nutrition research. Efficacy RCTs often lack external validity due to their fixed design and restrictive eligibility criteria, leading to efficacy-effectiveness and evidence-practice gaps. Adaptive trials improve the evaluation of nutritional intervention efficacy through planned study modifications, such as recalculating sample sizes or discontinuing a study arm. Pragmatic trials are embedded within clinical practice or conducted in settings that resemble standard of care, enabling a more comprehensive assessment of intervention effectiveness. Pragmatic trials often rely on patient-oriented primary outcomes, acquire outcome data from electronic health records, and employ broader eligibility criteria. Consequently, adaptive and pragmatic trials facilitate the prompt implementation of evidence-based nutritional recommendations into clinical practice. Recognizing the limitations of efficacy RCTs and the potential advantages of alternative trial designs is essential for bridging efficacy-effectiveness and evidence-practice gaps. Ultimately, this awareness will lead to a greater number of patients benefiting from evidence-based nutritional recommendations.

Dietary patterns, malnutrition, muscle loss and sarcopenia in cancer survivors: findings from the UK Biobank

PURPOSE

To identify dietary patterns derived from protein, polyunsaturated fatty acids (PUFA) and vitamin D and examine associations with malnutrition, low muscle mass and sarcopenia in cancer survivors.

METHODS

This cross-sectional study included cancer survivors (n = 2415) from the UK Biobank (age [mean ± SD] 59.7 ± 7.1 years; 60.7% female). The Oxford WebQ 24-h dietary assessment estimated food and nutrient intakes. Reduced rank regression derived dietary patterns (response variables: protein [g/kg/day], PUFA [g/day] and vitamin D [μg/day]). Adjusted logistic regression analysis examined associations between dietary patterns and malnutrition, low muscle mass and sarcopenia.

RESULTS

Three dietary patterns were identified: (i) 'high oily fish and nuts', characterised by higher oily fish and nuts and seeds intake; (ii) 'low oily fish', characterised by lower oily fish intake and higher potato intake; and (iii) 'meat and dairy', characterised by higher intake of meat, poultry and dairy. Eighteen percent of participants were malnourished, 5% had low muscle mass and 6.5% had sarcopenia. Odds of being malnourished were significantly lower with adherence to a 'high oily fish and nuts' pattern (OR: 0.57; 95% CI: 0.50, 0.65) and 'low oily fish' pattern (OR: 0.81; 95% CI: 0.73, 0.90). The 'meat and dairy' pattern was not associated with malnutrition. No dietary patterns were associated with low muscle mass or sarcopenia.

CONCLUSIONS

Energy-rich dietary patterns were associated with lower odds of malnutrition in cancer survivors but did not influence muscle mass or sarcopenia risk.

IMPLICATIONS FOR CANCER SURVIVORS

Better understanding of dietary patterns may improve cancer-related outcomes for cancer survivors.

Advances in nutritional supplementation for sarcopenia management

Sarcopenia is a syndrome characterized by a decline in muscular mass, strength, and function with advancing age. The risk of falls, fragility, hospitalization, and death is considerably increased in the senior population due to sarcopenia. Although there is no conclusive evidence for drug treatment, resistance training has been unanimously recognized as a first-line treatment for managing sarcopenia, and numerous studies have also pointed to the combination of nutritional supplementation and resistance training as a more effective intervention to improve quality of life for people with sarcopenia. People with both malnutrition and sarcopenia have a higher mortality rate, so identifying people at risk of malnutrition and intervening early is extremely important to avoid sarcopenia and its associated problems. This article provides important information for dietary interventions in sarcopenia by summarizing the discoveries and developments of nutritional supplements such as protein, leucine, β-hydroxy-β-methylbutyric acid, vitamin D, vitamin C, vitamin E, omega-3 fatty acids, creatine, inorganic nitrate, probiotics, minerals, collagen peptides, and polyphenols in the management of sarcopenia.

Comparative Effects of Different Nutritional Supplements on Inflammation, Nutritional Status, and Clinical Outcomes in Colorectal Cancer Patients: A Systematic Review and Network Meta-Analysis

Nutritional supplements have been widely used in colorectal cancer (CRC) patients. The aim of this network meta-analysis (NMA) was to compare the effects of different nutritional supplements on inflammation, nutritional status, and clinical outcomes in CRC patients. Four electronic databases were searched until December 2022. Randomized controlled trials (RCTs) comparing nutritional supplements of omega-3 fatty acids (omega-3), arginine, vitamin D, glutamine, probiotics, or their combinations with placebo or standard treatment were selected. The outcomes were inflammatory indicators, nutritional indicators, and clinical outcomes. A random-effects Bayesian NMA was performed to rank the effect of each supplement. In total, 34 studies involving 2841 participants were included. Glutamine was superior in decreasing tumor necrosis factor-α (MD -25.2; 95% CrI [-32.62, -17.95]), whereas combined omega-3 and arginine supplementation was more effective in decreasing interleukin-6 (MD -61.41; 95% CrI [-97.85, -24.85]). No nutritional supplements significantly maintained nutritional indicators in CRC patients. Regarding clinical outcomes, glutamine ranked highest in reducing the length of hospital stay (MD -3.71; 95% CrI [-5.89, -1.72]) and the incidence of wound infections (RR 0.12; 95% CrI [0, 0.85]), and probiotics were rated as best in reducing the incidence of pneumonia (RR 0.38; 95% CrI [0.15, 0.81]). Future well-designed RCTs are needed to further confirm these findings.

Microalgae Produce Antioxidant Molecules with Potential Preventive Effects on Mitochondrial Functions and Skeletal Muscular Oxidative Stress

In recent years, microalgae have become a source of molecules for a healthy life. Their composition of carbohydrates, peptides, lipids, vitamins and carotenoids makes them a promising new source of antioxidant molecules. Skeletal muscle is a tissue that requires constant remodeling via protein turnover, and its regular functioning consumes energy in the form of adenosine triphosphate (ATP), which is produced by mitochondria. Under conditions of traumatic exercise or muscular diseases, a high production of reactive oxygen species (ROS) at the origin of oxidative stress (OS) will lead to inflammation and muscle atrophy, with life-long consequences. In this review, we describe the potential antioxidant effects of microalgae and their biomolecules on mitochondrial functions and skeletal muscular oxidative stress during exercises or in musculoskeletal diseases, as in sarcopenia, chronic obstructive pulmonary disease (COPD) and Duchenne muscular dystrophy (DMD), through the increase in and regulation of antioxidant pathways and protein synthesis.

The association between fatty acid quality indices and quality of life among overweight and obese women: A cross-sectional study

Background

Reduced quality of life (QOL) is a major public health challenge affecting the global population. Fatty acid quality indices (FAQIs) are novel determinants of QOL and may impact various aspects of QOL. Prior research has established a significant link between dietary habits and QOL. However, the association between FAQIs and specific dimensions of QOL has not been established. Therefore, we aimed to investigate the association between FAQIs and QOL in overweight and obese women.

Methods

In total, 378 adult overweight or obese women participated in this cross-sectional study. Several anthropometric indices, systolic and diastolic blood pressure, and biochemical factors were measured using standard protocols. Dietary intake was assessed using a validated and reliable semi-quantitative food frequency questionnaire (the FFQ, 147 items). The cholesterol-saturated fat index (CSI) and the ratio of omega-6/omega-3 (N6/N3) essential fatty acids consumed were employed as FAQIs. The SF-36 questionnaire was administered to measure QOL. Linear logistic regression was used, in the form of raw and adjusted models, to evaluate the associations between FAQIs and QOL.

Results

The study sample consisted of 279 participants for whom ω-6/ω-3 ratio was measured and 378 participants for whom CSI was measured. The mean (±SD) age of participants was 36.65 ± 9.07 years. Linear logistic regression, with adjustment for potential confounders, such as age, energy intake, body mass index, employment, and thyroid status, indicated that ω-6/ω-3 intake ratio was negatively and marginally significantly associated with general health (β = -139.94, 95% CI: [-286.54, 6.66]; p = 0.061) and physical role limitations (β= -337.68, 95% CI: [-679.99, 1.61]; p = 0.051). A significant negative association was observed between ω-6/ω-3 intake ratio and social functioning (β = -247.54, 95% CI: [-458.14, -36.94]; p = 0.021), which indicates that obese and overweight women with a higher ω-6/ω-3 intake ratio obtained lower scores on social functioning.

Conclusions

It was found that FAQI scores were negatively associated with certain QOL measures among overweight and obese Iranian women, suggesting that a higher consumption of fatty acids, especially trans and saturated fatty acids, may be associated with lower QOL.

Efficacy and safety of Omega-3 polyunsaturated fatty acids in adjuvant treatments for colorectal cancer: A meta-analysis of randomized controlled trials

Background: Colorectal cancer (CRC) ranks third globally. There are many adverse reactions to treatments such as surgeries and post-surgical chemotherapy, which affect patients' prognosis and reduce their life quality. Omega-3 polyunsaturated fatty acids (O3FAs) have become an essential part of immune nutrition due to their anti-inflammatory properties, which improve body immunity and have attracted widespread attention. A systematic review focused on the efficacy and safety of O3FAs for patients undergoing surgeries in combination with chemotherapy or a surgery alone is lacking. Objectives: To evaluate the efficacy of O3FAs in the adjuvant treatment of CRC, a meta-analysis was conducted on patients with CRC who underwent surgeries in combination with chemotherapy or a surgery alone. Methods: As of March 2023, publications have been obtained using search terms from digital databases such as PubMed, Web of Science, Embase and Cochrane Library. Only randomized clinical trials (RCTs) evaluating the efficacy and safety of O3FAs following adjuvant treatments for CRC were included in the meta-analysis. Key outcomes were tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-1beta (IL-1β), albumin, body mass index (BMI), weight, the rate of infectious and non-infectious complications, the length of hospital stay (LOS), CRC mortality and life quality. Results: After screening 1,080 studies, 19 RCTs (n = 1,556) with O3FAs in CRC were included, in all of which at least one efficacy or safety outcome was examined. Compared to the control group, the level of TNF-α (MD = -0.79, 95% CI: 1.51 to -0.07, p = 0.03) and IL-6 was reduced due to O3FA-enriched nutrition during the perioperative period (MD = -4.70, 95% CI: 6.59 to -2.80, p < 0.00001). It also reduces LOS (MD = 9.36, 95% CI: 2.16 to 16.57, p = 0.01). No significant differences were found in CRP, IL-1β, albumin, BMI, weight, the rate of infectious and non-infectious complications, CRC mortality or life quality. The inflammatory status of patients with CRC undergoing adjuvant therapies decreased after a total parenteral nutrition (TPN) O3FA supplementation (TNF-α, MD = -1.26, 95% CI: 2.25 to -0.27, p = 0.01, I ² = 4%, n = 183 participants). The rate of infectious and non-infectious complications was reduced among patients with CRC undergoing adjuvant therapies after a parenteral nutrition (PN) O3FA supplementation (RR = 3.73, 95% CI: 1.52 to 9.17, p = 0.004, I ² = 0%, n = 76 participants). Conclusion: Our observations suggest that supplementation with O3FAs has little or no effect on patients with CRC undergoing adjuvant therapies and that a prolonged inflammatory state may be modified. To validate these findings, well-designed, large-scale, randomized and controlled studies on homogeneous patient populations are expected.

Preoperative Omega-6/Omega-3 Fatty Acid Ratio Could Predict Postoperative Outcomes in Patients with Surgically Resected Non-Small-Cell Lung Cancer

Introduction: The aim of this study was to determine whether preoperative nutritional status and inflammatory status, specifically polyunsaturated acids and the omega 6/3 ratio, would affect postoperative outcomes and complications in patients with lung cancer undergoing lung resection. Methods: This prospective observational study included 68 patients with early-stage non-small-cell lung cancer who were candidates for radical surgery. A complete nutritional assessment was performed. The primary study variable was postoperative complications and mortality in the first 30 days. Descriptive, bivariate, and logistic regression analyses were carried out. Results: A total of 50 men (73.53%) and 18 women (26.47%) underwent surgery, with a median age of 64.2 (±9.74) years. The mean omega 6/3 ratio was 17.39 (±9.45). A complication occurred in 39.7% of the study sample (n = 27), the most common being persistent air leak in 23.53% (n = 16). After performing the bivariate analysis, the only variable that remained significant was the omega 6/3 ratio; we observed that it had a prognostic value for persistent air leak (p = 0.001) independent of age, sex, comorbidity, preoperative respiratory function, and approach or type of surgery. The remaining nutritional and inflammatory markers did not have a statistically significant association (p > 0.05) with postoperative complications. However, this significance was not maintained in the multivariate analysis by a small margin (p = 0.052; 95% CI: 0.77-1.41). Conclusions: Omega 6/3 ratio may be a prognostic factor for air leak, independent of the patient's clinical and pathological characteristics.

Current Insights in Nutrition Assessment and Intervention for Malnutrition or Muscle Loss in People with Lung Cancer: A Narrative Review

Up to 70% of people with lung cancer may be affected by cancer-related malnutrition or muscle loss, depending on treatment modality and disease stage. This narrative review explores recent studies on malnutrition and muscle loss as well as nutritional and multimodal interventions to treat these conditions in the context of the changing treatment landscape in lung cancer. Various types of interventions, including individualized counseling, protein and other specific nutrient supplementation, as well as multimodal interventions to treat malnutrition and muscle loss, have been investigated. Overall, individualized dietary counseling, increasing protein intake, and supplementation with omega-3 (n-3) fatty acids appear to be beneficial for some, albeit varying, patient outcomes. Multimodal interventions, generally including a nutrition and exercise component, show promising results; however, the impact on patient outcomes is mixed. A key finding of this review is a lack of large, randomized trials to guide nutrition intervention specifically in people with lung cancer. Despite the high prevalence of malnutrition and muscle loss in people with lung cancer and the known adverse outcomes, current evidence for nutrition intervention is limited. A targeted effort is required to improve the quality of evidence for nutrition intervention in this population to provide support for clinicians to deliver effective nutrition care.

Non-Pharmacological Self-Management Strategies for Chemotherapy-Induced Peripheral Neuropathy in People with Advanced Cancer: A Systematic Review and Meta-Analysis

Non-pharmacological self-management interventions for chemotherapy-induced peripheral neurotherapy (CIPN) are of clinical interest; however, no systematic review has synthesized the evidence for their use in people with advanced cancer. Five databases were searched from inception to February 2022 for randomized controlled trials assessing the effect of non-pharmacological self-management interventions in people with advanced cancer on the incidence and severity of CIPN symptoms and related outcomes compared to any control condition. Data were pooled with meta-analysis. Quality of evidence was appraised using the Revised Cochrane Risk of Bias Tool for Randomized Trials (RoB2), with data synthesized narratively. Grading of Recommendations, Assessment, Development and Evaluations (GRADE) was applied to assess the certainty of the evidence. Thirteen studies were included, which had a high (69%) or unclear (31%) risk of bias. Greatest confidence was found for physical exercise decreasing CIPN severity (SMD: −0.89, 95% CI: −1.37 to −0.41; p = 0.0003; I² = 0%; n = 2 studies, n = 76 participants; GRADE level: moderate) and increasing physical function (SMD: 0.51, 95% CI: 0.02 to 1.00; p = 0.04; I² = 42%; n = 3 studies, n = 120; GRADE level: moderate). One study per intervention provided preliminary evidence for the positive effects of glutamine supplementation, an Omega-3 PUFA-enriched drink, and education for symptom self-management via a mobile phone game on CIPN symptoms and related outcomes (GRADE: very low). No serious adverse events were reported. The strongest evidence with the most certainty was found for physical exercise as a safe and viable adjuvant to chemotherapy treatment for the prevention and management of CIPN and related physical function in people with advanced cancer. However, the confidence in the evidence to inform conclusions was mostly very low to moderate. Future well-powered and appropriately designed interventions for clinical trials using validated outcome measures and clearly defined populations and strategies are warranted.

Mapping ongoing nutrition intervention trials in muscle, sarcopenia, and cachexia: a scoping review of future research

Muscle loss alone, or in the context of sarcopenia or cachexia, is a prevalent condition and a predictor of negative outcomes in aging and disease. As adequate nutrition is essential for muscle maintenance, a growing number of studies has been conducted to explore the role of specific nutrients on muscle mass or function. Nonetheless, more research is needed to guide evidence-based recommendations. This scoping review aimed to compile and document ongoing clinical trials investigating nutrition interventions as a strategy to prevent or treat low muscle mass or function (strength and physical performance), sarcopenia, or cachexia. ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform were searched up to 21 April 2021 for planned and ongoing trials. Randomized controlled trials with ≥20 participants per arm were included based on intent to explore the effects of nutrition interventions on muscle-related outcomes (i.e. muscle mass or strength, physical performance, or muscle synthesis rate) in both clinical and non-clinical conditions (i.e. aging). Two reviewers independently screened records for eligibility, and a descriptive synthesis of trials characteristics was conducted. A total of 113 trials were included in the review. Most trials (69.0%) enroll adults with clinical conditions, such as cancer (19.5%), obesity and metabolic diseases (16.8%), and musculoskeletal diseases (10.7%). The effects of nutrition interventions on age-related muscle loss are explored in 31% of trials. Although nutrition interventions of varied types were identified, food supplements alone (48.7%) or combined with dietary advice (11.5%) are most frequently reported. Protein (17.7%), amino acids (10.6%), and β-hydroxy-β-methylbutyrate (HMB, 6.2%) are the top three food supplements' nutrients under investigation. Primary outcome of most trials (54.9%) consists of measures of muscle mass alone or in combination with muscle strength and/or performance (as either primary or secondary outcomes). Muscle strength and physical performance are primary outcomes of 38% and 31.9% of the trials, respectively. These measurements were obtained using a variety of techniques. Only a few trials evaluate muscle synthesis rate either as a primary or secondary outcome (5.3%). Several nutrition studies focusing on muscle, sarcopenia, and cachexia are underway and can inform future research in this area. Although many trials have similar type of interventions, methodological heterogeneity may challenge study comparisons, and future meta-analyses aiming to provide evidence-based recommendations. Upcoming research in this area may benefit from guidelines for the assessment of therapeutic effects of nutrition interventions.

Effects of β-hydroxy β-methylbutyrate (HMB) supplementation on muscle mass, function, and other outcomes in patients with cancer: a systematic review

Low muscle mass is prevalent among patients with cancer and a predictor of adverse clinical outcomes. To counteract muscle loss, β-hydroxy β-methylbutyrate (HMB) supplementation has been proposed as a potential therapy for older adults and various diseases states. This systematic review aimed to investigate the effects and safety of HMB supplementation in relation to muscle mass and function and other clinical outcomes in patients with cancer. A systematic search of MEDLINE, CINAHL, Embase, Cochrane Central Register of Controlled Trials, Scopus, ProQuest, and grey literature for reports published from inception to December 2021 was conducted. Included studies provided supplements containing any dose of HMB to adult patients with active cancer. A synthesis without meta-analysis was conducted using a vote-counting approach based solely on the direction of the effect (i.e. regardless of statistical significance). Risk of bias was assessed for each outcome domain, and evidence from higher-quality studies (i.e. those with either low or moderate risk of bias) was examined. Safety was evaluated using both lower-quality and higher-quality studies. Fifteen studies were included, in which six were randomized controlled trials in patients with various cancer types and treatments. Studies prescribed HMB combined with amino acids (73.3%), HMB in oral nutritional supplements (20.0%), or both supplement types (6.7%); Ca-HMB doses of 3.0 g/day were provided in 80.0% of the studies. Four studies had high risk of bias across all outcome domains. Considering the higher-quality studies, evidence of a beneficial effect of HMB supplementation was found in four of four studies for muscle mass, two of two for muscle function, three of three for hospitalization, and five of seven for survival. In contrast, no beneficial effects of HMB on quality of life or body weight was found in two of four and three of five studies, respectively. A limited number of higher-quality studies evaluating the impact of HMB on cancer therapy-related toxicity, inflammation, and tumour response were observed. No serious adverse effects directly related to the nutrition intervention were reported. Although limited, current evidence suggests that HMB supplementation has a beneficial effect on muscle mass and function in patients with cancer. Well-designed trials are needed to further explore the clinical benefit of HMB supplementation in this patient population.

Effects of Omega-3 Supplementation Alone and Combined with Resistance Exercise on Skeletal Muscle in Older Adults: A Systematic Review and Meta-Analysis

Sarcopenia negatively affects skeletal muscle mass and function in older adults. Omega-3 (ω-3) fatty acid supplementation, with or without resistance exercise training (RET), is suggested to play a role as a therapeutic component to prevent or treat the negative effects of sarcopenia. A systematic review and meta-analysis were conducted on the impact of ω-3 fatty acid supplementation with or without RET on measures of muscle mass and function in older adults (≥55 y). The data sources included SPORTDiscus, PubMed, and Medline. All the study types involving ω-3 fatty acid supplementation on measures of muscle mass and function in older adults (without disease) were included. The mean differences (MDs) or standardized mean differences (SMDs) with 95% confidence intervals were calculated and pooled effects assessed. Sixteen studies (1660 females, 778 males) met our inclusion criteria and were included in the meta-analysis. ω-3 fatty acid supplementation did not impact lean tissue mass (SMD 0.09 [-0.10, 0.28]). Benefits were observed for lower body strength (SMD 0.54 [0.33, 0.75]), timed-up-and-go (MD 0.29 [0.23, 0.35]s), and 30-s sit-to-stand performance (MD 1.93 [1.59, 2.26] repetitions) but not walking performance (SMD -0.01 [-0.10, 0.07]) or upper body strength (SMD 0.05 [-0.04, 0.13]). Supplementing with ω-3 fatty acids may improve the lower-body strength and functionality in older adults.

The effect of long chain omega-3 polyunsaturated fatty acids on muscle mass and function in sarcopenia: A scoping systematic review and meta-analysis

BACKGROUND & AIMS

Sarcopenia is characterized by the progressive loss of skeletal muscle mass and function, which reduces mobility and quality of life. Risk factors for sarcopenia include advanced age, physical inactivity, obesity, and chronic diseases such as cancer or rheumatoid arthritis. Omega-3 long chain polyunsaturated fatty acids (LC PUFAs) might be associated with a reduction in risk of sarcopenia due to their anti-inflammatory effects.

METHODS

We conducted a systematic review and meta-analysis to quantify the effects of omega-3 LC PUFAs on muscle mass, volume and function parameters. The National Library of Medicine's MEDLINE/PubMed database was searched on 9th October 2020 for randomized controlled trials that used omega-3 LC PUFAs as an intervention with muscle-related endpoints. A snowballing search to identify additional studies was completed on 23rd April 2021. The meta-analysis was conducted using meta-essentials worksheet 3. Bias was assessed using the Jadad scale.

RESULTS

123 studies were identified with the systematic searches. Most studies were performed in disease populations, such as cancer or chronic obstructive pulmonary disease (COPD), or in healthy individuals after a fatiguing exercise bout. The endpoints lean body mass, skeletal muscle mass, mid-arm muscle circumference, handgrip strength, quadriceps maximal voluntary capacity (MVC), and 1-repetition maximum chest press were selected for meta-analysis based on the number of available studies; thus 66 studies were included in the quantitative synthesis. Using a random effects model and 2-tailed p-value, there was a significant relationship in favor of omega-3 LC PUFA supplementation for lean body mass (effect size 0.27, 95%CI 0.04 to 0.51), skeletal muscle mass (effect size 0.31, 95%CI 0.01 to 0.60) and quadriceps MVC (effect size 0.47, 95%CI 0.02 to 0.93).

CONCLUSION

The results indicate that there is a positive effect of omega-3 LC PUFA supplementation on overall body muscle mass and strength. Small study size and heterogeneity limit the applicability of these findings for sarcopenia prevention. Larger trials in populations at risk of sarcopenia would strengthen the evidence base.

Regulation of Skeletal Muscle Satellite Cell Differentiation by Omega-3 Polyunsaturated Fatty Acids: A Critical Review

Skeletal muscle is composed of multinuclear cells called myofibres, which are formed by the fusion of myoblasts during development. The size of the muscle fiber and mass of skeletal muscle are altered in response to several pathological and physiological conditions. Skeletal muscle regeneration is primarily mediated by muscle stem cells called satellite cells (SCs). In response to injury, these SCs replenish myogenic progenitor cells to form new myofibers to repair damaged muscle. During myogenesis, activated SCs proliferate and differentiate to myoblast and then fuse with one another to form muscle fibers. A reduced number of SCs and an inability to undergo myogenesis may contribute to skeletal muscle disorders such as atrophy, cachexia, and sarcopenia. Myogenic regulatory factors (MRF) are transcription factors that regulate myogenesis and determines whether SCs will be in the quiescent, activated, committed, or differentiated state. Mitochondria oxidative phosphorylation and oxidative stress play a role in the determination of the fate of SCs. The potential activation and function of SCs are also affected by inflammation during skeletal muscle regeneration. Omega-3 polyunsaturated fatty acids (PUFAs) show promise to reduce inflammation, maintain muscle mass during aging, and increase the functional capacity of the muscle. The aim of this critical review is to highlight the role of omega-3 PUFAs on the myogenic differentiation of SCs and pathways affected during the differentiation process, including mitochondrial function and inflammation from the current body of literature.