Higher adherence to Mediterranean Diet is associated with improved semen parameters: A systematic review and meta-analysis of observational studies

AbstractSemen quality is a key indicator of male fecundity and therefore is closely related to male fertility. In recent decades a significant decrease of semen parameters was observed worldwide. Except for environmental pollution, low physical activity, body weight and comorbidities, unhealthy diet was linked to semen quality decline. Mediterranean Diet (MedDiet) due to its anti-oxidative and anti-inflammatory properties, is considered as beneficial for semen. However, results of existing studies are inconclusive. The aim of this review was to pool associations between adherence to the MedDiet and semen quality parameters in observational studies. Electronic databases including PubMed, Embase and Scopus were searched until April 2019 with no restriction to language or time. Studies were eligible for inclusion if they filled following criteria: (1) observational design (retrospective or prospective), (2) adherence to MedDiet assessed using score or data-driven method and (3) semen quality parameters (total motility, progressive motility, total count, concentration or volume) as outcomes. Mean differences or odds ratios of abnormal semen parameters between the highest and lowest quintiles of MedDiet were converted to standardized mean differences (SMD). Random effects models with inverse variance method were used to pool differences. Heterogeneity was assessed using the Cochrane Q test and I2 statistic with value > 50% indicating substantial heterogeneity. Five cross-sectional studies extracted from 840 articles, met the eligibility criteria and were included in the meta-analysis. Higher adherence to MedDiet compared to lower adherence was associated with increased total (SMD = 0.59 95%CI: 0.12–1.06, I2 = 80%, pheterogenity < 0.01, n = 4) and progressive (SMD = 0.53 95%CI: 0.16–0.91, I2 = 0%, pheterogenity = 0.94, n = 2) sperm motility. No associations were observed between adherence to MedDiet and total sperm count (SMD = 0.14 95%CI: -0.20–0.48, I2 = 70%, pheterogenity < 0.01, n = 5), concentration (SMD = 0.22 95%CI: -0.04–0.47, I2 = 48%, pheterogenity = 0.10, n = 5), volume (SMD = 0.02 95%CI: -0.20–0.25, I2 = 21%, pheterogenity = 0.28, n = 5), as well as morphology (SMD = -0.10 95%CI: -0.36–0.16, I2 = 38%, pheterogenity = 0.18, n = 4). The results suggest that higher adherence to the MedDiet may have a protective effect on semen quality, probably by increased intake of antioxidant-rich products. Limitations of findings include substantial between-study heterogeneity and use of cross-sectional design. Beneficial effects of the MedDiet on semen quality have to be confirmed in further prospective studies.

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P–112 Association between dietary total antioxidant capacity and semen quality parameters in male partners of couples attempting fertility

Human Reproduction ◽

10.1093/humrep/deab130.111 ◽

2021 ◽

Vol 36 (Supplement_1) ◽

Author(s):

G Eslamian ◽

S Rohani ◽

N Shoaibinobarian

Keyword(s):

Antioxidant Capacity ◽

Dietary Pattern ◽

Total Antioxidant Capacity ◽

Semen Quality ◽

Sperm Count ◽

Quality Parameters ◽

Cross Sectional ◽

Abnormal Sperm ◽

Total Antioxidant ◽

Dietary Total Antioxidant Capacity

Abstract Study question Is there any association between dietary total antioxidant capacity (TAC) and semen quality parameters in male partners of couples attempting fertility? Summary answer Greater adherence to diets high in TAC was significantly associated with higher total sperm count, sperm concentration, and sperm motility. What is known already Among multiple factors that affect the etiology of poor semen quality and male infertility, dietary factors have an important contribution. Also, chronic oxidative stress negatively effects semen quality. Whether adherence to the diet rich in antioxidants is associated with better semen quality remains largely unexplored.The concentration of single antioxidant cannot show the total antioxidant power of the diet, therefore the concept of dietary total antioxidant capacity (TAC) was invented.Dietary scores are useful approach to evaluate the degree of adherence to specific dietary pattern and its benefits in regard to health Study design, size, duration This was a cross-sectional study of 350 men from couples attending a fertility center in Tehran, Iran, recruited between June 2015 and September 2019. Men aged 25–50 years with complete dietary data were analyzed. Participants/materials, setting, methods Diet was assessed via a reproducible and valid 168-item semi-quantitative food frequency questionnaire to determine the entire antioxidants of the usual diet in order to calculate dietary TAC. Semen quality was assessed according to World Health Organization 2010 guidelines. The association between dietary TAC and semen parameters were assessed adjusting for potential confounders through multiple logistic regression analysis. Main results and the role of chance The average age of study participants was 34.9 ± 7.6 years and their BMI was 28.5 ± 4.3 kg/m2. Participants in the lower tertile of the dietary TAC were lower educated (p < 0.01), more physically active (p < 0.05), and predominantly had abnormal sperm progressive motility (p < 0.01). In the multivariable adjusted models, men in the lowest tertile of the dietary TAC Score had 2.9 times higher likelihood of having abnormal sperm motility, total sperm count and concentration, compared to men in the highest tertile of the TAC score (p < 0.05). Limitations, reasons for caution The main limitation of our study was its cross-sectional design, limiting our ability to derive causal association. Wider implications of the findings: Our study suggests that dietary pattern comprising mainly of antioxidant nutrients may help improve semen quality. Our results are consistent with previous studies showing that plant-based diet contains higher levels of antioxidants are associated with better measures of semen quality. Trial registration number Not applicable

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Semen quality pattern and age threshold: a retrospective cross-sectional study of 71,623 infertile men in China, between 2011 and 2017

Reproductive Biology and Endocrinology ◽

10.1186/s12958-019-0551-2 ◽

2019 ◽

Vol 17 (1) ◽

Cited By ~ 1

Author(s):

W. N. Li ◽

M. M. Jia ◽

Y. Q. Peng ◽

R. Ding ◽

L. Q. Fan ◽

...

Keyword(s):

Semen Quality ◽

Sperm Count ◽

Sperm Concentration ◽

Cross Sectional Study ◽

Semen Parameters ◽

Sectional Study ◽

Joinpoint Regression ◽

Cross Sectional ◽

Progressive Motility ◽

Infertile Men

Abstract Background The aim of this study was to provide information on the semen quality pattern of infertile men and age thresholds for semen parameters in China. Methods This was a retrospective cross-sectional study investigating 71,623 infertile men from the Reproductive and Genetic Hospital of CITIC Xiangya in Hunan, China, from 2011 to 2017. The Kruskal-Wallis test, Mann-Kendall test, linear regression model and joinpoint regression were used. Results Although erratic changes were observed in the median semen parameters (sperm concentration 40.1–52.1 × 106/ml, total sperm count 117.8–153.1 × 106, sperm progressive motility 33.4–38.1%) during the 7 years of observation, no significant decrease in semen quality was found, and 47.88% of infertile men showed normal semen parameters according to the World Health Organization (WHO) criteria. According to the joinpoint regression analysis, sperm progressive motility appeared to decrease earlier than the sperm concentration and total sperm count (at 28, 58, and 42 years of age, respectively). Conclusions There is no evidence of a deterioration in semen quality among infertile men in Hunan, China. Semen parameters decreased with increasing age, with turning points noted at different ages. Semen parameters are not absolute evidence for the assessment of male fertility potential. Therefore, we believe that, among semen parameters, the sperm concentration is the best predictor of fertility for ART, followed by motility. Decreased sperm motility may affect natural pregnancy, but it is not necessary for successful IVF.

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Neighbourhood socioeconomic status and overweight/obesity: a systematic review and meta-analysis of epidemiological studies

BMJ Open ◽

10.1136/bmjopen-2018-028238 ◽

2019 ◽

Vol 9 (11) ◽

pp. e028238 ◽

Cited By ~ 7

Author(s):

Shimels Hussien Mohammed ◽

Tesfa Dejenie Habtewold ◽

Mulugeta Molla Birhanu ◽

Tesfamichael Awoke Sissay ◽

Balewgizie Sileshi Tegegne ◽

...

Keyword(s):

Systematic Review ◽

Socioeconomic Status ◽

Observational Studies ◽

Data Extraction ◽

Meta Analysis ◽

Epidemiological Studies ◽

Cochrane Library ◽

Eligibility Criteria ◽

Cross Sectional ◽

Neighbourhood Socioeconomic Status

ObjectiveLow neighbourhood socioeconomic status (NSES) has been linked to a higher risk of overweight/obesity, irrespective of the individual’s own socioeconomic status. No meta-analysis study has been done on the association. Thus, this study was done to synthesise the existing evidence on the association of NSES with overweight, obesity and body mass index (BMI).DesignSystematic review and meta-analysis.Data sourcesPubMed, Embase, Scopus, Cochrane Library, Web of Sciences and Google Scholar databases were searched for articles published until 25 September 2019.Eligibility criteriaEpidemiological studies, both longitudinal and cross-sectional ones, which examined the link of NSES to overweight, obesity or BMI, were included.Data extraction and synthesisData extraction was done by two reviewers, working independently. The methodological quality of included studies was assessed using the Newcastle-Ottawa Scale for the observational studies. The summary estimates of the relationships of NSES with overweight, obesity and BMI statuses were calculated with random-effects meta-analysis models. Heterogeneity was assessed by Cochran’s Q and I2 statistics. Subgroup analyses were done by age categories, continents, study designs and NSES measures. Publication bias was assessed by visual inspection of funnel plots and Egger’s regression test.ResultA total of 21 observational studies, covering 1 244 438 individuals, were included in this meta-analysis. Low NSES, compared with high NSES, was found to be associated with a 31% higher odds of overweight (pooled OR 1.31, 95% CI 1.16 to 1.47, p<0.001), a 45% higher odds of obesity (pooled OR 1.45, 95% CI 1.21 to 1.74, p<0.001) and a 1.09 kg/m2 increase in mean BMI (pooled beta=1.09, 95% CI 0.67 to 1.50, p<0.001).ConclusionNSES disparity might be contributing to the burden of overweight/obesity. Further studies are warranted, including whether addressing NSES disparity could reduce the risk of overweight/obesity.PROSPERO registration numberCRD42017063889

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Role of Dietary Antioxidants and Vitamins Intake in Semen Quality Parameters: A Cross-sectional Study

10.21203/rs.3.rs-42856/v1 ◽

2020 ◽

Author(s):

Reza Ghiasvand ◽

Laleh Dehghan Marvast ◽

Mehran Nouri ◽

Aida Jahanbakhsh ◽

farahnaz haeri

Keyword(s):

Dietary Intake ◽

Semen Quality ◽

Sperm Count ◽

Cross Sectional Study ◽

Quality Parameters ◽

Dietary Antioxidants ◽

Cross Sectional ◽

Infertile Men ◽

Semen Volume

Abstract Objective Infertility had an increasing trend between couples in Iran. Several factors such as lifestyle, physical activity, unhealthy dietary habits and stress are associated with production of ROS in seminal fluid. The aim of this study was to identify the role of dietary antioxidants and vitamins intake on semen quality parameters, among Iranian infertile men. Methods This cross-sectional study was performed on 400 newly diagnosed infertile men in Yazd Reproductive sciences Institute from July 2019 to December 2019. The presence of infertility was confirmed by an expert andrologist, based on WHO criteria. Dietary antioxidants and vitamins intake were assessed using a 168 items semi-quantitative food frequency questionnaire (FFQ). Results We found an association between semen volume and Alpha Carotene dietary intake, total motility and Beta Cryptoxanthin dietary intake, and sperm count with riboflavin intake (P = 0.03). Conclusions We concluded that dietary intake of Alpha Carotene, Beta Cryptoxanthin, and Riboflavin are related to sperm count, semen volume and total motility in Iranian infertile men, respectively. Our data suggest that that adhering to a diet that is rich in sources of antioxidant and vitamin can have a positive effect on men’s sexual health. However, more research is needed to confirm these relations and provide the evidence needed to exert these findings into clinical practice.

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Dietary Patterns and Poor Semen Quality Risk in Men: A Cross-Sectional Study

Nutrients ◽

10.3390/nu10091162 ◽

2018 ◽

Vol 10 (9) ◽

pp. 1162 ◽

Cited By ~ 8

Author(s):

Anna Danielewicz ◽

Katarzyna Przybyłowicz ◽

Mariusz Przybyłowicz

Keyword(s):

Dietary Patterns ◽

Semen Quality ◽

Sperm Quality ◽

Cross Sectional Study ◽

Quality Parameters ◽

Semen Parameters ◽

Sectional Study ◽

Cross Sectional ◽

Progressive Motility ◽

Increased Risk

The etiology of diminished sperm quality in about 30% of male infertility cases generally remains unexplained. Some studies have suggested that specific nutritional factors can affect semen quality. The aim of this study was to evaluate an association between dietary patterns (DPs) and the risk of abnormal semen quality parameters in men. This cross-sectional study was carried out in 114 men aged 20–55 years from Poland. Semen parameters were assessed via computer-aided semen. Diet was assessed by a food frequency questionnaire (FFQ). DPs were derived using Principal Component Analysis (PCA). Two DPs were derived: Pro-healthy and Western. After adjusting for potential confounders, the risk of abnormal progressive motility was significantly higher in the middle (OR: 2.89, 95% CI: 1.03–8.09) and upper (OR: 7.78, 95% CI: 1.52–15.06) tertiles of the Western DP. A trend for increased risk of the abnormal total count, progressive motility, and morphology (P-trend < 0.050) was found in Western DP. To conclude, the Western DP may increase the risk of abnormal semen parameters, whereas no association was found in the case of Pro-healthy DP. These findings stand in contrast to an increasing number of research findings indicating a positive relation between intake of healthy foods or diet and semen quality parameters. The results highlight the need to study whether modifications in diet and lifestyle factors improve semen quality.

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Association of the Dietary Approaches to Stop Hypertension, Physical Activity, and Their Combination with Semen Quality: A Cross-Sectional Study

Nutrients ◽

10.3390/nu12010039 ◽

2019 ◽

Vol 12 (1) ◽

pp. 39

Author(s):

Anna Danielewicz ◽

Jakub Morze ◽

Mariusz Przybyłowicz ◽

Katarzyna Eufemia Przybyłowicz

Keyword(s):

Physical Activity ◽

Semen Quality ◽

Sperm Count ◽

Sperm Concentration ◽

Cross Sectional Study ◽

Semen Parameters ◽

Sectional Study ◽

Cross Sectional ◽

Dash Diet ◽

Progressive Motility

The influence of individual lifestyle factors is widely described in studies on semen quality. However, their synergistic effect is often neglected. The aim of the study was to examine the association between semen quality and dietary approaches to stop hypertension (DASH) diet, physical activity (PA), and the two separately and in combination. A cross-sectional study was carried out among 207 men aged 20–55. Dietary data were collected by a food frequency questionnaire (FFQ) and analysed according to the DASH scoring index. Physical activity was evaluated by the International Physical Activity Questionnaire. Semen parameters were assessed via the computer-aided semen analysis (CASA). Adherence to the DASH diet was associated with higher sperm count (ΔT3-T1 = 82.1 mln/ej) and concentration (ΔT3-T1 = 24.6 mln/mL). Higher PA was related to higher sperm count (ΔT3-T1 = 69.4 mln/ej), total (ΔT3-T1 = 11.9%), and progressive motility (ΔT3-T1 = 8.5%) and morphology (ΔT3-T1 = 2.8%) in the crude model and remained significant after adjustment. The combination of the DASH diet and PA, was significantly positively associated with sperm count (ΔT3-T1 = 98.1 mln/ej), sperm concentration (ΔT3-T1 = 17.5 mln/mL), total (ΔT3-T1 = 11.8%), and progressive motility (ΔT3-T1 = 10.0%) and morphology (ΔT3-T1 = 3.3%) in both models. Adherence to the DASH diet was related to higher sperm count and concentration, whereas after its combination with physical activity it was also positively correlated with sperm motility and morphology.

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The association between alcohol consumption and telomere length: A meta-analysis focusing on observational studies

10.1101/374280 ◽

2018 ◽

Cited By ~ 2

Author(s):

Jianqiang Li ◽

Yu Guan ◽

Faheem Akhtar ◽

Xi Xu ◽

Ji-Jiang Yang ◽

...

Keyword(s):

Alcohol Consumption ◽

Telomere Length ◽

Observational Studies ◽

Meta Analysis ◽

Total Sample ◽

P Value ◽

Eligibility Criteria ◽

Cross Sectional ◽

Study Population ◽

Study Type

AbstractBackgroundBoth telomere length and alcohol consumption play important roles in carcinogenesis and biological age. Many efforts have been made to investigate the association between alcohol consumption and telomere length. However, no consensus has been reached yet.MethodsIn this article, we performed a meta-analysis to integrate the investigation results in the literature about the association between alcohol consumption and telomere length. After searching articles published between 2000 and 2016, 21 articles (including 27 analyses, total sample size 35,891) met our eligibility criteria.ResultsWe found a significant association between alcohol consumption and telomere length (Fisher’s combined p-value = 3.52E-8 and Liptak’s weighted p-value = 8.24E-3). We also found that the significance of the association between alcohol consumption and telomere length varies with study type (cohort, case-control, or cross-sectional) and study population (Europe, Asia, American, or Australia).ConclusionsCombined evidence showed that alcohol consumption is associated with telomere length. The consistent quantifications of alcohol consumption and telomere length would benefit the future aggregation of the evidence from different studies.

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The association between dietary inflammatory index and risk of central obesity in adults: An updated systematic review and meta-analysis

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000648 ◽

2020 ◽

Vol 90 (5-6) ◽

pp. 535-552 ◽

Cited By ~ 2

Author(s):

Mahdieh Abbasalizad Farhangi ◽

Mahdi Vajdi

Keyword(s):

Systematic Review ◽

Observational Studies ◽

Central Obesity ◽

Assessment Tool ◽

Weighted Mean Difference ◽

Meta Analysis ◽

Dietary Factors ◽

Cross Sectional ◽

Inflammatory Status ◽

Obesity Indices

Abstract. Backgrounds: Central obesity, as a pivotal component of metabolic syndrome is associated with numerous co-morbidities. Dietary factors influence central obesity by increased inflammatory status. However, recent studies didn’t evaluate the association between central obesity and dietary inflammation index (DII®) that give score to dietary factors according to their inflammatory potential. In the current systematic review and meta-analysis, we summarized the studies that investigated the association between DII® with central obesity indices in the general populations. Methods: In a systematic search from PubMed, SCOPUS, Web of Sciences and Cochrane electronic databases, we collected relevant studies written in English and published until 30 October 2019. The population of included studies were apparently healthy subjects or individuals with obesity or obesity-related diseases. Observational studies that evaluated the association between DII® and indices of central obesity including WC or WHR were included. Results: Totally thirty-two studies were included; thirty studies were cross-sectional and two were cohort studies with 103071 participants. Meta-analysis of observational studies showed that higher DII® scores were associated with 1.81 cm increase in WC (Pooled weighted mean difference (WMD) = 1.813; CI: 0.785–2.841; p = 0.001). Also, a non-significant increase in the odds of having higher WC (OR = 1.162; CI: 0.95–1.43; p = 0.154) in the highest DII category was also observed. In subgroup analysis, the continent, dietary assessment tool and gender were the heterogeneity sources. Conclusion: The findings proposed that adherence to diets with high DII® scores was associated with increased WC. Further studies with interventional designs are necessary to elucidate the causality inference between DII® and central obesity indices.

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Breakfast skipping and the risk of type 2 diabetes: a meta-analysis of observational studies

Public Health Nutrition ◽

10.1017/s1368980015000257 ◽

2015 ◽

Vol 18 (16) ◽

pp. 3013-3019 ◽

Cited By ~ 71

Author(s):

Huashan Bi ◽

Yong Gan ◽

Chen Yang ◽

Yawen Chen ◽

Xinyue Tong ◽

...

Keyword(s):

Type 2 Diabetes ◽

Observational Studies ◽

Meta Analysis ◽

Adjusted Relative Risk ◽

China National Knowledge Infrastructure ◽

Cross Sectional ◽

Breakfast Skipping ◽

Risk Estimates ◽

Increased Risk

AbstractObjectiveBreakfast skipping has been reported to be associated with type 2 diabetes (T2D), but the results are inconsistent. No meta-analyses have applied quantitative techniques to compute summary risk estimates. The present study aimed to conduct a meta-analysis of observational studies summarizing the evidence on the association between breakfast skipping and the risk of T2D.DesignSystematic review and meta-analysis.SettingRelevant studies were identified by a search of PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI) and SINOMED up to 9 August 2014. We also reviewed reference lists from retrieved articles. We included studies that reported risk estimates (including relative risks, odds ratios and hazard ratios) with 95 % confidence intervals for the association between breakfast skipping and the risk of T2D.SubjectsEight studies involving 106 935 participants and 7419 patients with T2D were included in the meta-analysis.ResultsA pooled adjusted relative risk for the association between exposure to breakfast skipping and T2D risk was 1·21 (95 % CI 1·12, 1·31; P=0·984; I2=0·0 %) in cohort studies and the pooled OR was 1·15 (95 % CI, 1·05, 1·24; P=0·770; I2=0·0 %) in cross-sectional studies. Visual inspection of a funnel plot and Begg’s test indicated no evidence of publication bias.ConclusionsBreakfast skipping is associated with a significantly increased risk of T2D. Regular breakfast consumption is potentially important for the prevention of T2D.

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