We have counseled our patients that lifestyle issues impact both men and women's reproductive capacity. An article in the September 2010 issue of Ferfility & Sterility defines the impact on semen parameters more clearly.
Thirteen socio-psycho-behavioral factors in 57 cross-sectional studies with 29,914 participants from 26 countries/regions were involved in this review. Six factors (age, body mass index [BMI], psychological stress, smoking, alcohol, and coffee consumption) were included in this review.
This review suggested that higher age, smoking, alcohol consumption, and psychological stress were risk factors for semen quality. This did not even take into account possible adverse changes in sperm that you cannot see in a semen analysis, such as DNA fragmentation which can be negatively impacted by these factors. These results indicated that health programs focusing on lifestyle and psychological health would be helpful for male reproductive health.
RPMG's Dr. David Meldrum has written extensively on this subject and his advice can be found in the on Lifestyle & Fertility page of our website with references to other sources.