Organic diet and fertility-possible effects of diet on male reproductive parameters

Summary

Lifestyle and environmental exposure to various chemical substances are believed to be, partially, responsible for an apparent increase in reproductive health problems in both wildlife and humans. The incidence in abnormalities in reproduction and – organs is seemingly increasing in many wildlife populations, and the culprit is believed to be various manmade chemicals present in the general environment. Moreover, a large body of evidence points towards human reproductive health being adversely affected. Male reproductive health has apparently been negatively affected and many reports of, for instance, declining sperm counts have been published. As the changes observed are too recent to be attributable to genetics, lifestyle and environmental factors are believed to be responsible.
One example of a possible contributing lifestyle factor is diet and its quality. Many of the pesticides used to produce conventional fruits and vegetables have been observed to disturb male reproductive health in animal studies. When spraying crops with pesticides some residue is bound to be present afterwards. Whether that residue is large enough to be detectable by chemical analysis is less certain. The effect of exposure to residual amounts of several pesticides simultaneously and over a longer period of time is uncertain. Furthermore, differences in content of nutrients and “health promoting substances” have been suggested as one important aspect. In this context the question of whether organic fruit and vegetables, as opposed to conventional ones, may be superior in relation to both reproductive and general health arises.
To shed some light on some of the differences between organic and conventional fruits and vegetables the effects of dietary intake on a number of male reproductive parameters were studied. A multigenerational study was designed; three generations of rats were bred while being fed fruit/vegetable diets produced either organically or conventionally. A control group fed standard rat chow was included for comparative reasons. A number of biomarkers for male reproductive health were investigated: reproductive organ weight, sperm quantity and aspects of quality and testicular histopathology.
None of the investigated parameters differed between animals in the different diet groups. All results were similar in animals fed organically, conventionally and the standard rat chow. It is important to emphasize that the conclusion that no difference in male reproductive health existed between animals fed organically or conventionally, only regards this study design. It is furthermore important to stress that the study design can be altered and improved both in terms of what biomarkers are evaluated, the age of the animals studied and diet production and composition.
To underscore the usability and sensitivity of study design, animal model and biomarkers seasonal variation was observed in all parameters investigated. Seasonality was observed in both body - and organ weights, sperm quantity and histopathology, and was in large part consistent with the reproductive seasonality observed in feral rats. The persistence of seasonal variation in animals bred and maintained under constant housing conditions provides food for thought regarding the presence of such stable biological rhythms.