New study below.
No Australians involved this time - LOL.
The estimable Edward Giovannucci has been tracking 32,000 men since 1992:
"... the hazard ratio for PCa incidence for ≥21 compared to 4–7 ejaculations per month was 0.81 ..."
"These findings provide additional evidence of a beneficial role of more frequent ejaculation throughout adult life in the etiology of PCa, particularly for low-risk disease."
A strange, I feel, take on this is ejaculation as detox. (Don't mention that to your partner.)
My own view is that ejaculation frequency might reflect testosterone [T] levels. There are a number of studies that associate PCa with lower T. I fear that many men are trying harder since reading the news - alas, to no avail.
The men who claimed >20 / month were different in a number of ways:
- greater body mass index (26.3 versus 25.6)
- greater calorie intake (2013 versus 1847)
- greater alcohol intake (12.2 versus 8.4 g/day)
- greater divorce rate (11.8 versus 4.9)
- greater number of smokers - in the past 10 years (39.6 versus 33.5)
- greater reported history of syphilis or gonorrhea (4.6 versus 1.2)
- greater vasectomy (27.9 versus 18.2)
-Patrick
FULL Text: europeanurology.com/article...
europeanurology.com/article...
Abstract
Background
Evidence suggests that ejaculation frequency may be inversely related to the risk of prostate cancer (PCa), a disease for which few modifiable risk factors have been identified.
Objective
To incorporate an additional 10 yr of follow-up into an original analysis and to comprehensively evaluate the association between ejaculation frequency and PCa, accounting for screening, clinically relevant disease subgroups, and the impact of mortality from other causes.
Design, setting, and participants
A prospective cohort study of participants in the Health Professionals Follow-up Study utilizing self-reported data on average monthly ejaculation frequency. The study includes 31 925 men who answered questions on ejaculation frequency on a 1992 questionnaire and followed through to 2010. The average monthly ejaculation frequency was assessed at three time points: age 20–29 yr, age 40–49 yr, and the year before questionnaire distribution.
Outcome measurements and statistical analysis
Incidence of total PCa and clinically relevant disease subgroups. Cox models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).
Results and limitations
During 480 831 person-years, 3839 men were diagnosed with PCa. Ejaculation frequency at age 40–49 yr was positively associated with age-standardized body mass index, physical activity, divorce, history of sexually transmitted infections, and consumption of total calories and alcohol. Prostate-specific antigen (PSA) test utilization by 2008, number of PSA tests, and frequency of prostate biopsy were similar across frequency categories. In multivariable analyses, the hazard ratio for PCa incidence for ≥21 compared to 4–7 ejaculations per month was 0.81 (95% confidence interval [CI] 0.72–0.92; p < 0.0001 for trend) for frequency at age 20–29 yr and 0.78 (95% CI 0.69–0.89; p < 0.0001 for trend) for frequency at age 40–49 yr. Associations were driven by low-risk disease, were similar when restricted to a PSA-screened cohort, and were unlikely to be explained by competing causes of death.
Conclusions
These findings provide additional evidence of a beneficial role of more frequent ejaculation throughout adult life in the etiology of PCa, particularly for low-risk disease.
Patient summary
We evaluated whether ejaculation frequency throughout adulthood is related to prostate cancer risk in a large US-based study. We found that men reporting higher compared to lower ejaculatory frequency in adulthood were less likely to be subsequently diagnosed with prostate cancer.
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