Table 2.

Summary of the studies that investigated dietary patterns or intakes of food compounds

Reference	Intervention or assessment	Inclusion criteria	Size of population; type of study	Outcome(s)	Conclusion
Afeiche et al. (2014)70	Dietary assessment	Men aged 18–55 y, from couples using their own gametes for IUI or assisted reproductive technologies, without a history of vasectomy	n = 155; observational	Total sperm count, sperm concentration, progressive motility, sperm morphology, and semen volume	Low-fat dairy intake, particularly low-fat milk, is related to higher sperm concentration and progressive motility
Afeiche et al. (2014)71	Dietary assessment	Men aged 18–55 y, from couples using their own gametes for IUI or assisted reproductive technologies, without a history of vasectomy	n = 155; observational	Semen quality parameters	Processed meat intake was negatively associated with sperm morphology, whereas fish intake was positively associated with total sperm count and sperm morphology
Afeiche et al. (2014)72	Dietary assessment	Men aged 18–22 y, able to read and speak English, and able to contact their mother and ask her to complete a questionnaire	n = 189; cross-sectional	Semen quality parameters	Processed red meat intake was inversely related to total sperm count and total progressive motile sperm count
Gaskins et al. (2012)28	Dietary assessment	Men aged 18–22 y, able to read and speak English, and able to contact their mother and ask her to complete a questionnaire	n = 188; observational	Semen quality parameters	A diet rich in fruits, vegetables, fish, chicken, and whole grains may improve at least 1 measure of semen quality
Mendiola et al. (2009)48	Assessment of recorded dietary habits and food consumption	Men with severe or moderate oligozoospermia and severe teratozoospermia	n = 60 (30 T and 30 C); observational	Semen parameters, hormone levels, Y microdeletions, and karyotypes	Frequent intake of lipophilic foods such as meat products or milk may negatively affect semen quality, whereas intake of some fruits or vegetables may maintain or improve semen quality
Braga et al. (2012)25	Assessment of recorded dietary and social habits	Male patients undergoing ICSI cycles	n = 250; observational	Semen parameters and ICSI outcomes	Intakes of fruits, cereals, and vegetables were positively related to sperm quality and implantation rate. Meat intake, as well as food deprivation or high BMI, was negatively correlated with ICSI success
Eslamian et al. (2012)2	Assessment of usual dietary intakes	Men with asthenozoospermia	n = 241 (72 T and 169 C); observational	Semen volume and sperm concentration, motility, and morphology	A higher intake of processed meat and sweets was positively associated with the risk of asthenozoospermia, whereas a high intake of fruits, vegetables, poultry, skim milk, and seafood was associated with a lower risk
Chavarro et al. (2008)64	Assessment of intake of 15 soy-based foods in the previous 3 mo	Male partners in subfertile couples	n = 99; observational	Semen quality	Higher intake of soy foods and soy isoflavones is associated with lower sperm concentration
Safarinejad et al. (2011)63	Two saffron capsules, twice daily (total of 60 mg) for 26 wk	Age <45 y, unable to conceive a child for >24 mo before the study with the same partner, total testicular volume >12 mL, and a normal fertile female partner	n = 230 (114 T and 116 C); RCTs	Semen parameters and total seminal plasma antioxidant capacity	Saffron does not statistically improve semen parameters in infertile men with idiopathic OAT

Abbreviations: BMI, body mass index; C, control group; ICSI, intracytoplasmic sperm injection; IUI, intrauterine insemination; OAT, oligoasthenoteratozoospermia; RCT, randomized controlled trial; T, treatment group.