Appearances can be deceptive

Organic growers dedicate themselves to a philosophy of maintaining healthy soils without addition of chemical sprays or growth agents. Natural soil additives such as organic manures, seaweed, and worm compost are provided to ensure the availability of all minerals and trace elements, including magnesium, iron, calcium, iodine, chromium and selenium. Despite any similarities in appearance, nutritional analysis of organic produce will reveal higher concentrations of these mineral elements compared with samples raised in poor soils using chemical fertiliser and other synthetic additives.

Mineral content

Minerals play a key role in the growth and regeneration of bone and soft tissue. They are integral to many aspects of metabolic function including the regulation of body temperature, digestion and waste removal. At the cellular level, they are required to facilitate the transmission of nerve impulses. They are also required to regulate the assimilation of important vitamin groups. Both iron and zinc, for example, are required by the body to absorb vitamins E and C. In summary, minerals are essential for normal functioning, health and vitality.

According to prominent nutrition specialists, the widely established practice of raising food crops in mineral deficient soils has contributed to the current epidemic of degenerative disease and related health conditions. Marie-France Muller (PH.D) has studied the effects of mineral deficiency in humans. Drawing from a range of medical, scientific, and historical sources, Muller proposes that the contemporary prevalence of negative farming methods have resulted in poor quality foods and inadequate nutrition. As a consequence, many individuals suffer from ailments which are linked to the depletion and imbalance of essential minerals within the body (Muller, 2005).

A few publicised studies have compared the mineral content of organic and standard grown produce. While most failed to report consistent differences, Smith (1993) points out that their analysis was based on the dry ashed concentration. His own comparison of elemental mineral concentrations was based on a fresh weight basis, and concluded that organically grown foods contained on average, over ninety percent more of the key mineral elements. For example, concentrations of zinc, calcium, and magnesium, were all approximately fifty percent higher in organic foods, while concentration of the key antioxidant mineral selenium was reported to be at least several times higher in the organic items.

In contrast, primary producers who choose conventional agricultural practices grow their crops in lower quality soils with the assistance of chemical sprays and fertilisers. Instead of a balanced complement of natural soil minerals and trace elements, plants are exposed to the manufactured growth elements (chemical compounds containing nitrogen, potassium, and phosphorus) that guarantee maximum yield per acre.

It is widely appreciated that chemical fertilisers alter the rate of plant growth and the ability to store water, however there is less acknowledgement of compositional changes occurring within the food chain. Research comparing the nutrient profiles of organic and standard agricultural produce report nitrate levels to be significantly higher for standard produce (Williams, 2002). According to food safety groups, the most serious health risk associated with elevated nitrates is the possibility of them converting to nitrosamines, which are carcinogenic.

Vitamin C content

Another consistent finding from comparative studies is the significantly higher vitamin C content of organically grown produce, particularly among the leafy vegetables and citrus fruits. This fact appears to have escaped widespread publicity and has been dismissed on several counts by adherents of the mainstream and sceptics of the organic approach.

One of the responses from those seeking to dismiss the organic movement and which tends to trivialise the vitamin C issue, is the possibility that organic produce contains a lower volume of water per unit weight. In other words the vitamin C content is simply concentrated in most organic produce. These commentators have then suggested that vitamin C is a relatively abundant nutrient in most fresh produce, and therefore, the advantages of higher concentration are outweighed by the additional cost and scarcity of organically grown fruit and vegetables.

From the alternative perspective, a more appropriate context for comparison would be consideration of the integrated nutrient capacity. Like many other nutrients, vitamin C is most effective when combined with complex mixtures of natural compounds which are readily obtained from high quality plant foods.

While not classified as nutrients themselves, compounds such as flavonoids, phyto-oestrogens, glucosinates, and phenolics, are slowly revealing the range of their co-enzymatic, restorative, and therapeutic effects. Several of the identified phenolic compounds, for example, appear to provide antioxidant protection against degenerative conditions, including coronary heart disease and several types of cancer. Under natural conditions, many of these compounds are generated by plants as a stress response or for protection against predatory attack.

Since mainstream agriculture depends on chemicals to treat most problems, plants are more likely to be deficient in these naturally protective compounds than organically grown varieties. This hypothesis was recently confirmed by Asami (2003), who reported the phenolic content of organic strawberries to be significantly higher compared with identical varieties grown according to conventional practices.

Consumers choose organic

When it comes to fresh produce and nutrition, it is certainly true that similarities in external appearances can be deceptive. Many consumers, who are becoming increasingly aware of this fact, are choosing organic items in preference to their conventional counterparts.