Evaluating the Serum and Seminal Plasma Levels of Zinc and Cadmium in Smokers and Their Relation to the Semen Parameters
Main article: Increase your sperm count
A prospective cohort study was conducted to evaluate serum and seminal plasma levels of zinc and cadmium in smokers compared to non-smokers.
A total of 70 volunteers aged between 20 to 40 years old were chosen from the Faculty of Medicine, Andrology outpatient clinic attached to Menoufia University. Group 1 consisted of 35 males who smoked more than 20 cigarettes a day for a year, while Group 2 was the control group, featuring 35 males who never smoked.
During initial assessment for study inclusion, males with a nutritional zinc deficiency, chronic liver or renal failure, acrodermatitis, enteropathica, chronic diarrhea, occupational heavy metal exposure, varicocele, drug use, abnormal hormone profile or testicular size were excluded to reduce potential biases.
Semen samples were collected following 2 to 5 days of abstinence and analysed according to the WHO laboratory manual for human semen testing and processing (5th edition), while zinc and cadmium levels were anaylsed using an Inductively Coupled Plasma Mass Spectrometer (ICP-MS) for maximum accuracy.
Baseline characteristics comparing the 2 groups showed no significant difference in mean age, martial status, period of marriage or frequency of intercourse per week. However comparison of semen analysis results found a significant decrease in sperm concentration (41.2 vs 64.3 million/mL), motility (33.9 vs 44.8 %) and viability (59.4 vs 69.3 %), while abnormal forms was higher (48.4 vs 40.4 %) for the smokers group compared to non smokers.
Interestingly serum (blood) levels of zinc and cadmium showed no significant difference between the two groups (P > 0.7). On the other hand seminal levels of zinc (-64.2mg/L) and cadmium (+14.6µg/dL) was significantly worse in the smokers group.
In the smokers group, statistical analysis showed;
- Seminal zinc levels correlated negatively with smoking index, and positively with sperm motility and viability
- Seminal cadmium levels correlated positively with age and smoking index, and negatively with sperm density, motility and viability
Similarly, in the non-smokers group, statistical analysis showed;
- Seminal zinc levels correlated positively with sperm count and motility
- Serum zinc levels correlated positively with sperm motility and negatively with the percentage of abnormal forms.
Further analysis found seminal zinc levels correlated directly (negatively) with seminal cadmium levels, while serum zinc levels did not correlate with serum cadmium levels at all.
SUMMARY: DOES SMOKING CIGARETTES AFFECT SPERM
In this study, men who smoke 20 or more cigarettes a day showed significantly decreased sperm concentration (41.2 vs 64.3 million/mL), motility (33.9 vs 44.8%), and viability (59.4 vs 69.3%) compared to non-smokers, with increased percentage of abnormal sperm forms (48.4 vs 40.4%).
- Small study size
- Mild and moderate smokers not included
Pant N, et al. (2015). Correlation between lead and cadmium concentration and semen quality. https://doi.org/10.1111/and.12342
Taha E A, et al. (2013). Correlation between seminal lead and cadmium and seminal parameters in idiopathic oligoasthenozoospermic males. https://dx.doi.org/10.5173/ceju.2013.01.art28
Liu R Z, et al. (2010). Seminal plasma zinc level may be associated with the effect of cigarette smoking on sperm parameters. https://doi.org/10.1177/147323001003800318
Kiziler A R, et al. (2007). High levels of cadmium and lead in seminal fluid and blood of smoking men are associated with high oxidative stress and damage in infertile subjects. https://doi.org/10.1007/s12011-007-8020-8
Telisman S, et al. (2000). Semen quality and reproductive endocrine function in relation to biomarkers of lead, cadmium, zinc, and copper in men. https://dx.doi.org/10.1289/ehp.0010845
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