The economic and social load of infertility is significant. Poor semen quality plays an important function in this problem, and between 20–50% of infertile couples have one or more abnormal semen parameters . The results of the current research showed that after BMI and age adjustment, the intake of saturated fatty acids dietary was significantly greater in abnormal count and morphology of semen compared with the normal sperm quality. Our data were consistent with the results of a Spanish study showing that processed meat use, an significant resource of saturated fatty acids, is related with of inferior quality in semen . In contrast, men with traditional Dutch diet contain great meat had high sperm concentrations than men who used a diet contained high in fruits, vegetables and fish . In a previous cross-sectional study involving 99 men, high levels of saturated fatty acids with a negative sperm concentration were found . Compared with PUFAs, fatty acids sperm is associated quality transformants in a different way. Chavarro et al. reported that fatty acids within semen were inversely associated with semen concentration. Zerbarinati et al. showed that higher levels of seminal elaidic acid in men with higher oligostenosomespermic semen compared to those with neurozoospermic semen. Human and animal studies have shown that high saturation, saturation and fatty acids intake adversely affects semen quality [24, 25]. In conclusion, different fatty acids contents in sperm and semen plasma have been described in individuals with pathological conditions compared to fertile men. It can be speculated that fatty acids characteristics can be a good indicator of male infertility and that incorporating proper dietary fatty acids may be a potential treatment for infertility.
It is important to note that oxidative stress (OS) is known to be one of the main mediators of male infertility because spermatozoa are more susceptible to OS. The OS occurs when there is an inequality between the creation of active oxygen species (ROS) and the inability to disable these toxic products. To prevent oxidative damage or stress, the body has developed a mechanism to protect against antioxidants, which is not always completely effective. For this reason, some researchers have paying attention their studies on antioxidant supplements . Concerning dietary factors, in our study a lesser dietary amount of some antioxidant nutrients such as vitamin E has been associated with abnormal quality sperm (concentration and motility). Antioxidants are thought to stabilize cell membranes and protect cells from free radicals . In Mendiola et al. study, vitamin E in that case-control study was not associated with good sperm quality. But Eskenazi et al. was performed on 97 healthy non-smoker men aged 20 to 80 years from a nonclinical condition. It was associated with progressive sperm motility in healthy men. Moslemi and Tavanbakhsh  demonstrated that supplementation of selenium and vitamin E in infertile men considerably improved sperm quality and mobility.
Moreover, in our study, the dietary intake of antioxidant selenium has been related with count, concentrations and motility of semen. Based on our knowledge, the function of selenium in male infertility is still largely unknown, although some data about its role in protecting against oxidative stress there . In the relation with selenium and sperm quality, it appears that they are mediated by increased glutathione peroxidase-1 action, shaving of hydrogen peroxide molecules and reduced ROS construction in sperm . Finding from Cochrane systematic review included low-quality RCTs and small population have been showed beneficial effect of selenium on sperm concentrations, total sperm motility and morphology [32, 33]. In last systematic review, it was concluded that additional research with larger homogeneous groups was required to evaluate the effect of vitamins and minerals on sperm, so the conclusion of supplement recommendations in the treatment of male infertility was presented.
Furthermore, dietary intake of linoleic acids has been related with count and morphology of semen. Composition of sperm cell membrane fatty acids is crucial for suitable sperm role. Omega-3 fatty acids are polyunsaturated fatty acids (PUFAs) with anti-inflammatory and antioxidant characteristic [34, 35]. In the case of omega-3 fatty acids, with linoleic acids, researches have shown that they perform by changing the composition of cell membranes by combining them in spermatozoon cell membranes and helps cell function . It has been shown that consumption of these fatty acids or their dietary sources changes the composition of sperm and semen fatty acids. Diets containing EPA and DHA, increase testicular DHA concentrations in rodents [36–38] and humans . The DHA content of the sperm membrane, in turn, has been related with normal morphology [39, 40]. In addition, the intake of these fatty acids and their food sources has been linked with sperm quality. In observational researches, the larger use of omega-3 PUFA was related with a larger amount of normal morphologic sperm  and fish using of total sperm count and normal sperm morphology .
Another attractive antioxidant related to fertility is zinc which in our study was related to the concentration, motility and morphology of semen. In particular in sperm, zinc acts as a source of membrane stability by inhibiting membrane-dependent oxidative enzymes for example NAD(P)H oxidases , with increasing sperm concentrations and motility . Zinc is as well necessary for the proper sperm density/descending sperm DNA. Low sperm content of sperm zinc is linked with some cases of male infertility . Finding from Cochrane systematic review included low-quality RCTs of and small population have been showed beneficial effect of zinc on sperm concentrations and total sperm motility [32, 33].
Our finding showed that vitamin D intake was lower in normal motility of semen compared with abnormal sperm quality. However, many studies in humans on the association between vitamin D levels and semen quality have yielded inconsistent findings [46–49]. In a cross-sectional research including healthy young Danish men, a positive correlation was found between serum vitamin D and sperm motility . Likewise, further studies of fertile and infertile men showed that men with vitamin D had elevated sperm motility than those with vitamin D deficiency [51, 52]. Another study including 104 men also found a positive relationship between vitamin D and progressive sperm motility . However, some other studies yielded inconsistent results. Abbasihormozi et al. reported that serum vitamin D levels have been reported to be unrelated to semen parameters and reproductive hormones in the fertile subjects, whereas in subjects with oligostenosomal or teratozoospermia, there is a positive relationship between vitamin D and sperm viability. Hammoud et al. was found that extreme or inadequate levels of serum vitamin D are associated with poor semen parameters such as sperm concentration and viability. Human Studies have shown that vitamin D regulates the flow of sperm cholesterol, affects the serum protein and phosphorylation of sperm threonine, thereby enhancing sperm survival . However, further studies are needed to elucidate the underlying mechanism of the effects of vitamin D on spermatosomes. Sperm motility is the main variable related to the achievement of fertilization, supported by the fact that progress in sperm motility makes sperm reach the fertilization site more easily and leads to higher fertility success rates [56, 57]. Given the positive association between dietary intake of vitamin D, zinc, vitamin E and selenium in our study and sperm function, additional researches on the underlying mechanism of vitamin D effects should be done in vitro.
It is essential to consider the strengths and limitations of our study. Our study has several strengths including a larger sample size using standard measures to accurately assess dietary intake. Finally, a validated FFQ was used for diet assessment which is a standard tool for evaluation of nutritional behavior in cross-sectional and cohort studies. There are some limitations. Our study was limited to a sample recruited from an infertility clinic, so it is impossible to generalize the finding to the whole population of male. Moreover, all patients participating the study were married and Islamic. In addition, analysis of a one semen sample from each patient should be recognized, although it has been recommended that analysis of numerous semen samples for each patient may not be better in research studies [58, 59]. In addition, since diet analysis was restricted to the nutrition database, glycemic load could not be calculated in this study. Further studies with larger sample size recruited from a less homogenous population which allowed comparison across culture and religious affiliation are recommended.