Coffee and caffeine intake and male infertility: a systematic review

Abstract

BackgroundSemen quality, a predictor of male fertility, has been suggested declining worldwide. Among other life style factors, male coffee/caffeine consumption was hypothesized to influence semen parameters, but also sperm DNA integrity. To summarize available evidence, we performed a systematic review of observational studies on the relation between coffee/caffeine intake and parameters of male fertility including sperm ploidy, sperm DNA integrity, semen quality and time to pregnancy.MethodsA systematic literature search was performed up to November 2016 (MEDLINE and EMBASE). We included all observational papers that reported the relation between male coffee/caffeine intake and reproductive outcomes: 1. semen parameters, 2. sperm DNA characteristics, 3. fecundability. All pertinent reports were retrieved and the relative reference lists were systematically searched in order to identify any potential additional studies that could be included.ResultsWe retrieved 28 papers reporting observational information on coffee/caffeine intake and reproductive outcomes. Overall, they included 19,967 men. 1. Semen parameters did not seem affected by caffeine intake, at least caffeine from coffee, tea and cocoa drinks, in most studies. Conversely, other contributions suggested a negative effect of cola-containing beverages and caffeine-containing soft drinks on semen volume, count and concentration. 2. As regards sperm DNA defects, caffeine intake seemed associated with aneuploidy and DNA breaks, but not with other markers of DNA damage. 3. Finally, male coffee drinking was associated to prolonged time to pregnancy in some, but not all, studies.ConclusionsThe literature suggests that caffeine intake, possibly through sperm DNA damage, may negatively affect male reproductive function. Evidence from epidemiological studies on semen parameters and fertility is however inconsistent and inconclusive. Well-designed studies with predefined criteria for semen analysis, subject selection, and life style habits definition, are essential to reach a consistent evidence on the effect of caffeine on semen parameters and male fertility.

Endocrine Effects of Coffee Consumption

“…Few prospective studies also reported that male caffeine consumption was associated with reduced fecundability (70,73). Coffee intake might indulge in DNA breaks and aneuploidy (84). Curtis et al (65), Wesselink et al (85) also found a slight decrease in fecundability with coffee consumption.…”

Caffeine improves sperm quality, modulates steroidogenic enzyme activities, restore testosterone levels and prevent oxidative damage in testicular and epididymal tissues of scopolamine-induced rat model of amnesia

“…Several experimental studies have established that caffeine exhibit therapeutic effects against cardiovascular diseases, inflammation, including memory impairment and cognitive disorders such as dementia and Alzheimer's disease . Furthermore, research has also shown the link between consumption of caffeine and fertility . Consumption of high dose of caffeine has been linked with impairment in male fertility.…”

“…[4,5] Furthermore, research has also shown the link between consumption of caffeine and fertility. [6] Consumption of high dose of caffeine has been linked with impairment in male fertility. Dorostghoal et al [7] reported that caffeine reduced testosterone levels and lowers germial epithelium height, weight of testis and diameter of seminiferous tubules.…”

Diet and Nutritional Factors in Male (In)Fertility – Underestimated Factors

“…In the meta-analysis, covering 57 cross-sectional studies which included 29914 participants, no significant effect of coffee on sperm quality was found [35]. Interestingly, a review of 28 observational studies, which involved 19 967 men, suggested that caffeine from coffee, tea and cocoa beverages did not have a negative impact on the quality of semen, as opposed to sweet drinks containing caffeine, the consumption of which in many studies was associated with a decreased semen volume and count, as well as with lower sperm concentration [38].…”