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Human Reproduction Update May 2024The last decade has seen increased research on the relationship between diet and male fertility, but there are no clearly defined nutritional recommendations for men in...
BACKGROUND
The last decade has seen increased research on the relationship between diet and male fertility, but there are no clearly defined nutritional recommendations for men in the preconception period to support clinical fertility outcomes.
OBJECTIVE AND RATIONALE
The purpose of this scoping review is to examine the extent and range of research undertaken to evaluate the effect(s) of diet in the preconception period on male clinical fertility and reproductive outcomes.
SEARCH METHODS
Four electronic databases (MEDLINE and EMBASE via Ovid, CAB Direct, and CINAHL via EBSCO) were searched from inception to July 2023 for randomized controlled trials (RCTs) and observational studies (prospective/retrospective, case-control, and cross-sectional). Intervention studies in male participants or couples aiming to achieve dietary or nutritional change, or non-intervention studies examining dietary or nutritional components (whole diets, dietary patterns, food groups or individual foods) in the preconception period were included. Controls were defined as any comparison group for RCTs, and any/no comparison for observational studies. Primary outcomes of interest included the effect(s) of male preconception diet on clinical outcomes such as conception (natural or via ART), pregnancy rates and live birth rates. Secondary outcomes included time to conception and sperm parameters.
OUTCOMES
A total of 37 studies were eligible, including one RCT and 36 observational studies (prospective, cross-sectional, and case-control studies; four studies in non-ART populations) published between 2008 and 2023. Eight reported clinical outcomes, 26 reported on secondary outcomes, and three reported on both. The RCT did not assess clinical outcomes but found that tomato juice may benefit sperm motility. In observational studies, some evidence suggested that increasing fish or reducing sugar-sweetened beverages, processed meat or total fat may improve fecundability. Evidence for other clinical outcomes, such as pregnancy rates or live birth rates, showed no relationship with cereals, soy and dairy, and inconsistent relationships with consuming red meat or a 'healthy diet' pattern. For improved sperm parameters, limited evidence supported increasing fish, fats/fatty acids, carbohydrates and dairy, and reducing processed meat, while the evidence for fruits, vegetables, cereals, legumes, eggs, red meat and protein was inconsistent. Healthy diet patterns in general were shown to improve sperm health.
WIDER IMPLICATIONS
Specific dietary recommendations for improving male fertility are precluded by the lack of reporting on clinical pregnancy outcomes, heterogeneity of the available literature and the paucity of RCTs to determine causation or to rule out reverse causation. There may be some benefit from increasing fish, adopting a healthy dietary pattern, and reducing consumption of sugar-sweetened beverages and processed meat, but it is unclear whether these benefits extend beyond sperm parameters to improve clinical fertility. More studies exploring whole diets rather than singular foods or nutritional components in the context of male fertility are encouraged, particularly by means of RCTs where feasible. Further assessment of core fertility outcomes is warranted and requires careful planning in high-quality prospective studies and RCTs. These studies can lay the groundwork for targeted dietary guidelines and enhance the prospects of successful fertility outcomes for men in the preconception period. Systematic search of preconception diet suggests that increasing fish and reducing sugary drinks, processed meats and total fat may improve male fertility, while consuming healthy diets, fish, fats/fatty acids, carbohydrates and dairy and reducing processed meat can improve sperm health.
Topics: Humans; Male; Diet; Pregnancy; Female; Fertility; Preconception Care; Pregnancy Rate
PubMed: 38237150
DOI: 10.1093/humupd/dmad035 -
Clinical Nutrition ESPEN Feb 2024Severe burns lead to metabolic changes, systemic inflammatory response syndrome, and multiple organ dysfunction syndrome. Omege-3 polyunsaturated fatty acids (PUFAs)... (Meta-Analysis)
Meta-Analysis
BACKGROUND & AIMS
Severe burns lead to metabolic changes, systemic inflammatory response syndrome, and multiple organ dysfunction syndrome. Omege-3 polyunsaturated fatty acids (PUFAs) have anti-inflammatory properties. In the absence of substantial evidence for use on major burns, we systematically reviewed the efficacy of omega-3 PUFAs for patients with severe burns.
METHODS
We comprehensively searched MEDLINE, Web of Science, Embase, Cochrane Library, China National Knowledge Internet, Wang Fang Data, Chinese Biomedicine Database, and Science Direct databases to collect randomised controlled trials of omega-3 PUFAs administered to patients with burns from January 2000 to June 2023. Two researchers independently screened the literatures, extracted the data, and assessed the risk of bias in the included studies. The outcomes were mortality, the risk of severe sepsis, septic shock, and multiple organ dysfunction syndrome. Data synthesis was conducted using Review Manager. Trial sequential analyses (TSA) for outcomes were performed.
RESULTS
Three randomised controlled trials involving 140 patients were included. Of these, 71 patients received omega-3 PUFAs. The results showed that omega-3 PUFAs significantly reduced the incidence of severe sepsis, septic shock, multiple organ dysfunction syndrome (RR = 0.38, 95 % CI [0.19, 0.75], P = 0.005), C-reactive protein levels (MD = -39.70[-81.63, 2.23], P = 0.06), and improved respiratory outcomes. However, there was no difference in 14-day mortality (RR = 1.10, 95%CI [0.59, 2.05], P = 0.75). TSA showed that the results for the incidence of severe sepsis, septic shock, multiple organ dysfunction syndrome are insufficient and inconclusive.
CONCLUSIONS
Omega-3 PUFAs may reduce inflammatory response and risk of sepsis, septic shock, and multiple organ dysfunction syndrome in severe burns patients and may shorten hospital stay but cannot reduce risk of death. Due to the limitation of the quantity and quality of the included studies, the evidence level is low, and the conclusions need to be verified by larger scale and higher quality randomised controlled trials.
Topics: Humans; Burns; Fatty Acids, Omega-3; Fatty Acids, Unsaturated; Multiple Organ Failure; Randomized Controlled Trials as Topic; Sepsis; Shock, Septic
PubMed: 38220365
DOI: 10.1016/j.clnesp.2023.11.019 -
Nutrients Jan 2024Many epidemiological studies have evaluated the intake of macronutrients and the risk of mortality and cardiovascular disease (CVD). However, current evidence is... (Meta-Analysis)
Meta-Analysis Review
Many epidemiological studies have evaluated the intake of macronutrients and the risk of mortality and cardiovascular disease (CVD). However, current evidence is conflicting and warrants further investigation. Therefore, we carried out an umbrella review to examine and quantify the potential dose-response association of dietary macronutrient intake with CVD morbidity and mortality. Prospective cohort studies from PubMed, Embase, and CENTRAL were reviewed, which reported associations of macronutrients (protein, fat, and carbohydrate) with all-cause, CVD, cancer mortality, or CVD events. Multivariable relative risks (RR) were pooled, and heterogeneity was assessed. The results of 124 prospective cohort studies were included in the systematic review and 101 in the meta-analysis. During the follow-up period from 2.2 to 30 years, 506,086 deaths and 79,585 CVD events occurred among 5,107,821 participants. High total protein intake was associated with low CVD morbidity (RR 0.88, 95% confidence interval 0.82-0.94), while high total carbohydrate intake was associated with high CVD morbidity (1.08, 1.02-1.13). For fats, a high intake of total fat was associated with a decreased all-cause mortality risk (0.92, 0.85-0.99). Saturated fatty acid intake was only associated with cancer mortality (1.10, 1.06-1.14); Both monounsaturated fatty acid (MUFA) and polyunsaturated fatty acids (PUFA) intake was associated with all-cause mortality (MUFA: 0.92, 0.86-0.98; PUFA: 0.91, 0.86-0.96). This meta-analysis supports that protein intake is associated with a decreased risk of CVD morbidity, while carbohydrate intake is associated with an increased risk of CVD morbidity. High total fat intake is associated with a low risk of all-cause mortality, and this effect was different in an analysis stratified by the type of fat.
Topics: Humans; Cardiovascular Diseases; Prospective Studies; Eating; Nutrients; Dietary Carbohydrates; Fatty Acids, Monounsaturated; Neoplasms
PubMed: 38201983
DOI: 10.3390/nu16010152 -
Respiratory Medicine Jan 2024Type 2 (T2) inflammation is a key mechanism in the pathophysiology of asthma. Diet may have immunomodulatory effects, and a role for diet in T2 inflammation has been... (Review)
Review
INTRODUCTION
Type 2 (T2) inflammation is a key mechanism in the pathophysiology of asthma. Diet may have immunomodulatory effects, and a role for diet in T2 inflammation has been suggested in the literature. Indeed, diet and food allergies play a role in children with atopic asthma, but less is known about diet in relation to adult asthma, which is often non-atopic.
OBJECTIVE
To review the effect of dietary interventions on markers of T2 inflammation in adults with asthma.
METHODS
The databases PubMed, Embase, Cochrane Library, and CINAHL were searched for eligible studies until December 2022. We included studies of all types of foods, nutrients, diets or supplements, either as an exposure or as an intervention, in adults and adolescents with asthma. Outcomes of interest included the T2 biomarkers FeNO, eosinophils, IL-4, IL-5, IL-13, eosinophil cationic protein and eosinophil peroxidase. The methodological quality of eligible studies was systematically evaluated, and the results were summarised according to dietary clusters.
RESULTS
The systematic search identified studies on the dietary clusters antioxidants (n = 14), fatty acids, (n = 14), Mediterranean-style diets (n = 5), phytotherapy (n = 7), prebiotics & probiotics (n = 8), vitamin D (n = 7), and other dietary factors (n = 5). Studies within the phytotherapy and omega-3 poly-unsaturated fatty acids (PUFA) clusters showed possible improvements in T2 inflammation. Furthermore, we found little evidence for an effect of antioxidants, prebiotics & probiotics, and Mediterranean-style diets on T2 inflammation. However, heterogeneity in study protocols, methodological shortcomings and limited power of almost all studies make it difficult to fully determine the impact of different dietary approaches on T2 inflammation in asthma.
CONCLUSIONS
Overall, the current evidence does not support a specific dietary intervention to improve T2 inflammation in asthma. Interventions involving phytotherapy and omega-3 PUFA currently have the best evidence and warrant further evaluation in well-designed and adequately powered studies, while taking into account T2-high phenotypes of asthma.
Topics: Adult; Child; Adolescent; Humans; Dietary Supplements; Antioxidants; Diet; Asthma; Fatty Acids, Omega-3; Inflammation
PubMed: 38141862
DOI: 10.1016/j.rmed.2023.107504 -
Advances in Nutrition (Bethesda, Md.) Jan 2024The high concentration of omega-3 polyunsaturated fats, dietary fibers, vitamins, minerals, and polyphenols found in nuts suggest their regular consumption may be a... (Meta-Analysis)
Meta-Analysis Review
The high concentration of omega-3 polyunsaturated fats, dietary fibers, vitamins, minerals, and polyphenols found in nuts suggest their regular consumption may be a simple strategy for improving reproductive health. This systematic review and meta-analysis aimed to present up-to-date evidence regarding the association between nut intake and fertility outcomes in males and females. Ovid MEDLINE, Embase, CINAHL, and Scopus were searched from inception to 30 June 2023. Eligible articles were interventional or observational studies in human subjects of reproductive age (18-49 y) that assessed the effects (or association) of dietary nut consumption (for a minimum of 3 mo) on fertility-related outcomes. Random-effects meta-analyses were completed to produce a pooled effect estimate of nut consumption on sperm total motility, vitality, morphology, and concentration in healthy males. Four studies involving 875 participants (646 males, 229 females) were included in this review. Meta-analysis of 2 RCTs involving 223 healthy males indicated consumption of ≥ 60g nuts/d increased sperm motility, vitality, and morphology in comparison to controls but had no effect on sperm concentration. Nonrandomized studies reported no association between dietary nut intake and conventional sperm parameters in males, embryo implantation, clinical pregnancy or live birth in males and females undergoing ART. Our meta-analysis shows that including at least 2 servings of nuts daily as part of a Western-style diet in healthy males improves sperm parameters, which are predictors of male fertility. Due to their nutritional profile, nuts were found to have potential to promote successful reproductive outcomes. This trial was registered at PROSPERO (CRD42020204586).
Topics: Female; Humans; Male; Pregnancy; Diet, Western; Fertility; Nuts; Seeds; Sperm Motility; Adolescent; Young Adult; Adult; Middle Aged
PubMed: 37977328
DOI: 10.1016/j.advnut.2023.100153 -
BMC Medicine Nov 2023There is growing evidence that substituting animal-based with plant-based foods is associated with a lower risk of cardiovascular diseases (CVD), type 2 diabetes (T2D),... (Meta-Analysis)
Meta-Analysis
BACKGROUND
There is growing evidence that substituting animal-based with plant-based foods is associated with a lower risk of cardiovascular diseases (CVD), type 2 diabetes (T2D), and all-cause mortality. Our aim was to summarize and evaluate the evidence for the substitution of any animal-based foods with plant-based foods on cardiometabolic health and all-cause mortality in a systematic review and meta-analysis.
METHODS
We systematically searched MEDLINE, Embase, and Web of Science to March 2023 for prospective studies investigating the substitution of animal-based with plant-based foods on CVD, T2D, and all-cause mortality. We calculated summary hazard ratios (SHRs) and 95% confidence intervals (95% CI) using random-effects meta-analyses. We assessed the certainty of evidence (CoE) using the GRADE approach.
RESULTS
In total, 37 publications based on 24 cohorts were included. There was moderate CoE for a lower risk of CVD when substituting processed meat with nuts [SHR (95% CI): 0.73 (0.59, 0.91), n = 8 cohorts], legumes [0.77 (0.68, 0.87), n = 8], and whole grains [0.64 (0.54, 0.75), n = 7], as well as eggs with nuts [0.83 (0.78, 0.89), n = 8] and butter with olive oil [0.96 (0.95, 0.98), n = 3]. Furthermore, we found moderate CoE for an inverse association with T2D incidence when substituting red meat with whole grains/cereals [0.90 (0.84, 0.96), n = 6] and red meat or processed meat with nuts [0.92 (0.90, 0.94), n = 6 or 0.78 (0.69, 0.88), n = 6], as well as for replacing poultry with whole grains [0.87 (0.83, 0.90), n = 2] and eggs with nuts or whole grains [0.82 (0.79, 0.86), n = 2 or 0.79 (0.76, 0.83), n = 2]. Moreover, replacing red meat for nuts [0.93 (0.91, 0.95), n = 9] and whole grains [0.96 (0.95, 0.98), n = 3], processed meat with nuts [0.79 (0.71, 0.88), n = 9] and legumes [0.91 (0.85, 0.98), n = 9], dairy with nuts [0.94 (0.91, 0.97), n = 3], and eggs with nuts [0.85 (0.82, 0.89), n = 8] and legumes [0.90 (0.89, 0.91), n = 7] was associated with a reduced risk of all-cause mortality.
CONCLUSIONS
Our findings indicate that a shift from animal-based (e.g., red and processed meat, eggs, dairy, poultry, butter) to plant-based (e.g., nuts, legumes, whole grains, olive oil) foods is beneficially associated with cardiometabolic health and all-cause mortality.
Topics: Humans; Animals; Diet; Prospective Studies; Diabetes Mellitus, Type 2; Olive Oil; Vegetables; Meat; Cardiovascular Diseases; Butter; Risk Factors
PubMed: 37968628
DOI: 10.1186/s12916-023-03093-1 -
Annals of Surgery Mar 2024To clarify whether perioperative immunonutrition is effective in adult patients with or without malnutrition undergoing elective surgery for head and neck (HAN) or... (Meta-Analysis)
Meta-Analysis
Impact of Perioperative Immunonutrition on Postoperative Outcomes for Patients Undergoing Head and Neck or Gastrointestinal Cancer Surgeries: A Systematic Review and Meta-analysis of Randomized Controlled Trials.
OBJECTIVE
To clarify whether perioperative immunonutrition is effective in adult patients with or without malnutrition undergoing elective surgery for head and neck (HAN) or gastrointestinal (GI) cancers.
BACKGROUND
It is important to avoid postoperative complications in patients with cancer as they can compromise clinical outcomes. There is no consensus on the efficacy of perioperative immunonutrition in patients with or without malnutrition undergoing HAN or GI cancer surgery.
MATERIALS AND METHODS
We searched MEDLINE (PubMed), MEDLINE (OVID), EMBASE, Cochrane Central Register of Controlled Trials, Web of Science Core Selection, and Emcare from 1981 to 2022 using search terms related to immunonutrition and HAN or GI cancer. We included randomized controlled trials. Intervention was defined as immunonutritional therapy including arginine, n-3 omega fatty acids, or glutamine during the perioperative period. The control was defined as standard nutritional therapy. The primary outcomes were total postoperative and infectious complications, defined as events with a Clavien-Dindo classification grade ≥ II that occurred within 30 days after surgery.
RESULTS
Of the 4825 patients from 48 included studies, 19 had upper GI cancer, 9 had lower, and 8 had mixed cancer, whereas 12 had HAN cancers. Immunonutrition reduced the total postoperative complications (relative risk ratio: 0.78; 95% CI, 0.66-0.93; certainty of evidence: high) and infectious complications (relative risk ratio: 0.71; 95% CI, 0.61-0.82; certainty of evidence: high) compared with standard nutritional therapy.
CONCLUSIONS
Nutritional intervention with perioperative immunonutrition in patients with HAN and GI cancers significantly reduced total postoperative complications and infectious complications.
Topics: Adult; Humans; Immunonutrition Diet; Randomized Controlled Trials as Topic; Gastrointestinal Neoplasms; Postoperative Complications; Fatty Acids, Omega-3; Malnutrition
PubMed: 37882375
DOI: 10.1097/SLA.0000000000006116 -
European Neuropsychopharmacology : the... Jan 2024Growing evidence suggests an association between inflammatory processes and depressive disorders (DD). DD typically emerge during adolescence. Treatment effects of... (Meta-Analysis)
Meta-Analysis Review
Growing evidence suggests an association between inflammatory processes and depressive disorders (DD). DD typically emerge during adolescence. Treatment effects of agents with anti-inflammatory properties in youth DD have not been systematically reviewed. Here, the existing evidence on the use of anti-inflammatory drugs (including polyunsaturated fatty acids, nonsteroidal anti-inflammatory drugs, cytokine inhibitors, statins, pioglitazone, corticosteroids, and minocycline or modafinil) in children and adolescents with DD was synthesized using meta-analysis. The PROSPERO preregistered search yielded 22 records meeting search criteria. Of these, data from 19 primary studies (n = 1366 subjects) were subjected to meta-analysis. A significant but small effect in favor of anti-inflammatory agents in reducing depressive symptoms in youth with DD was found (SMD = -0.29, 95 % CI = -0.514; -0.063, p = 0.01). Post-hoc analyzes of drug subclasses found a significant effect of omega-3 fatty acids in reducing depressive symptoms. Results underline the importance to consider inflammatory pathways in the supplemental treatment of youth with DD. Further research is warranted, to clarify if anti-inflammatory agents are only effective in a subpopulation of patients (inflammatory biotype of depression in youth) and/or to alleviate specific symptom domains of depression (e.g., cognitive symptoms).
Topics: Child; Humans; Adolescent; Depression; Anti-Inflammatory Agents; Minocycline; Pioglitazone; Fatty Acids, Omega-3
PubMed: 37864981
DOI: 10.1016/j.euroneuro.2023.09.006 -
Pharmacological Research Nov 2023Long-chain n-3 poly unsaturated fatty acids have anti-inflammatory effects but their effects on serum levels of adhesion molecules are inconsistent and contradictory. In... (Meta-Analysis)
Meta-Analysis
Long-chain n-3 poly unsaturated fatty acids have anti-inflammatory effects but their effects on serum levels of adhesion molecules are inconsistent and contradictory. In this updated systematic review and meta-analysis, marine sources of omega-3 fatty acids were pooled up to determine the effects of omega-3 supplementation on adhesion molecules. PubMed-Medline, SCOPUS, Web of Science and Google Scholar databases (from inception to April 2023) were searched and all RCTs investigating the effects of marine sources of omega-3, on blood concentrations of adhesion molecules were included and a meta-analysis undertaken. Forty-two RCTs were included involving 3555 participants aged from 18 to 75 years. Meta-analysis of 38 arms from 30 RCTs reporting serum concentrations of vascular cell adhesion molecule-1 (VCAM-1) showed a significant reduction after omega-3 supplementation (WMD: -1.26, 95% CI: -1.88 to -0.64 ng/mL, P < 0.001). Meta-analysis of 40 arms from 30 RCTs reporting serum concentrations of intercellular adhesion molecule-1 (ICAM-1) revealed a reduction following omega-3 supplementation, although it was not significant (WMD: -1.76, 95%CI: -3.68 to 0.16 ng/mL, P = 0.07). Meta-analysis of 27 arms from 21 trials showed no effect on E-selectin (WMD: 0.01, 95%CI: -0.02 to 0.04 ng/mL, P = 0.62). Pooling 15 arms from 11 RCTs showed a marginally significant reducing effect on P-selectin concentrations (WMD: -2.67, 95%CI: -5.53 to 0.19 ng/mL, P = 0.06). A considerable decrease in VCAM concentration was observed after omega-3 supplementation in this meta-analysis with a trend to decreases in both ICAM and P-selectin levels, with effects that may be significant depending on study design, and there was no effect on E-selectin.
Topics: Humans; E-Selectin; P-Selectin; Randomized Controlled Trials as Topic; Cell Adhesion Molecules; Vascular Cell Adhesion Molecule-1; Fatty Acids; Fatty Acids, Omega-3; Dietary Supplements
PubMed: 37863453
DOI: 10.1016/j.phrs.2023.106963 -
Nutrients Sep 2023The menopausal transition is often accompanied with distressing manifestations, such as vasomotor symptoms, sleep disruptions, and depressive syndrome. Omega-3... (Review)
Review
The menopausal transition is often accompanied with distressing manifestations, such as vasomotor symptoms, sleep disruptions, and depressive syndrome. Omega-3 polyunsaturated fatty acids (-3 PUFAs) have emerged as a potential intervention to alleviate these symptoms. This review aimed to comprehensively assess the impact of -3 PUFAs supplementation on vasomotor symptoms, sleep quality, and depression among postmenopausal women. We conducted a systematic literature search of randomized controlled trials across the Cochrane Library, Web of Science, PubMed, CINAHL, EMBASE, and SCOPUS databases from inception to August 2023. Among the initial pool of 163 identified studies, nine studies met the inclusion criteria and were incorporated into this systematic review. Notably, four studies detected potential benefits of -3 PUFAs in improving hot flashes and night sweats. On the contrary, sleep quality outcomes displayed heterogeneity across the studies. Incorporating diverse scales, such as the Hamilton Depression Rating Scale-21, the Patient Health Questionnaire depression scale, and Generalized Anxiety Disorder-7 for depression outcomes, we found inconclusive evidence of -3 PUFA's impact on depression. Overall, the combined analysis of these studies did not provide substantial evidence to support the efficacy of -3 PUFAs in improving vasomotor symptoms, sleep quality, and depression. Further well-designed randomized clinical trials with larger participant groups are crucial to validate and generalize these results. Review Registration: PROSPERO registration no: CRD42023421922.
Topics: Female; Humans; Postmenopause; Sweating; Sleep Quality; Depression; Hot Flashes; Fatty Acids, Omega-3
PubMed: 37836515
DOI: 10.3390/nu15194231