Diet, lifestyle and human fertility

Human fertility is influenced by many factors, with diet and lifestyle being amongst those which can be regulated and improved where necessary. In reviewing those studies completed to date, the association between impaired fertility and certain dietary and lifestyle factors appears well established. The clearest evidence relates to nutrient imbalances and the specific effects of certain synthetic and organic chemicals which are sometimes present in foods, soil, and the wider environment.

Since the beginnings of the industrial revolution, many human populations have been exposed to an array of synthetic chemical substances, often delivered directly into the food chain through contaminated soils, water, and atmospheres.

Several major studies have identified the negative contribution of smoking and tobacco smoke exposure (Chia, et al 1994; Kunzle, et al 2003; Jensen, et al, 1998; Harlow, et al, 2000). For male subjects, the risks include sexual dysfunction and significantly decreased semen quality. Female smokers risk early menopause and overall declines in the efficiency of ovulation.

A range of synthetic chemical compounds have been linked to fertility problems in human populations. The majority of these are derived from organic hydrocarbons which form the basis of the petroleum, pharmaceutical, and agrochemical industries. Within each industry, there are suspect or harmful compounds categorised as solvents, pesticides, plasticizers, and pharmacological agents. The level of concern must be increased when these compounds are detected in both natural and manufactured food sources. For example, synthetic growth hormones are often detectable in meat and poultry products. These pharmacological agents are widely used for contemporary stock management despite evidence of their impact on human reproductive development. Similarly, the widespread use of synthetic pesticides and other agricultural chemicals have contributed to the alteration of environmental safety within the traditional food chain. One of the consequences has been the gradual promotion of holistic agriculture and organically certified foods.

Studies investigating the fertility related effect of pesticide exposure have focused upon those individuals directly engaged with their manufacture and application (Slutsky, et al. 1999; Goldsmith 1997; Potashnik and Porath 1995). While biological markers of decreased fertility are generally observed, the outcomes of such studies are often clouded by the possibility of external factors which cannot be controlled in their design or implementation. For similar reasons, it is even less practical to measure the influence of pesticides contained within the biological food chain.

As fertility protection and treatment becomes increasingly medicalised, there are many individuals who choose to focus on the long term benefits of healthy diet, regular exercise, and the avoidance of specific risk factors like smoking, substance abuse, pesticide exposure, and environmental pollutants.

The foods most likely to enhance fertility are the fresh vegetables and fruits containing rich supplies of antioxidant nutrients. If possible, include a selection of different colours for each meal and try to obtain these from chemical free soils (organically certified producers).

Green: Avocadoes, spinach, broccoli, sprouts, limes, olives, mangoes, watercress, and herbs.

Red/Orange: Carrots, beetroot, tamarind, capsicum, sweet potato, apples, grapes, tomatoes, and cumquats.

Yellow: Bananas, squash, turmeric, capsicum, saffron, lemons, grapefruit, melon, and tomatoes.

Dark: Aubergine, plums, cherries, cloves, blackberries, blueberries, olives, and sea vegetables.