Is Organic Produce Better For You?

Is there any scientific evidence at all regarding the alleged nutritional superiority of organic fruits and veggies?

A good reference point is two studies, both published recently, regarding the nutritional value of organically-raised produce versus conventionally-produced. The first was a European Union-funded project in the U.K. Conducted over a four-year period, the Quality Low Input Food Project (QLIF) divided a 725-acre farm in half, raising conventional produce (and dairy cows) and their organic counterparts almost side by side. The initial results, published in October 2007, showed that organic tomatoes, potatoes, cabbage, onions and lettuce contained up to 40% more antioxidants and higher levels of some vitamins and minerals (such as copper, iron, vitamin C and zinc) than conventional examples of the same fruits and vegetables. Organically-raised wheat also contained these higher levels of antioxidants and minerals. And the milk from organically-farmed dairy cows was found to have between 50% and 90% more antioxidants (depending upon which media outlet you credit) than conventionally-produced milk.

The USDA and the FSA (Food Standards Agency—the U.K. equivalent of the USDA) have long maintained that organic foods are no more nutritious than conventional foods. Doesn’t this study prove them wrong? Well, not quite. Not yet, anyway. The full results of the U.K. study, which will not be published until sometime this year, showed significant variations in nutrient levels between organic and conventional produce; some conventionally-grown crops proved to have higher vitamin contents than those of the same species raised organically. In addition, as any small-scale farmer can tell you, fruits and vegetables are about the most variable foods out there. They are enormously influenced by species, microclimate during any particular growing season, soil condition, and more. (If you don’t believe me, look at the quality of any brand of vintage wine over a period of several years. You’ll notice changes in the wine with each vintage, often significant, usually caused by how good or poor a year it was for the wine grapes.) It’s possible that different species of lettuce or onion might have produced very different findings, or that if the study had been carried out for a longer period of time, the results might have been more (or less) in favor of organic produce. So I find this study interesting, but not conclusive. However, there was another set of results published in 2007 with less fanfare, which I find more intriguing.

From 1994 to 2004, in a study conducted by researchers from the University of California at Davis, both organic and conventionally-grown tomatoes of one species were dried, then measured for levels of two flavonoids (a type of antioxidant): quercetin and kaempferol. Over the decade-long study, the mean levels of quercetin were 79% higher in organically-grown tomatoes, while the average kaempferol levels of the organic tomatoes were 97% higher than in conventionally-grown tomatoes. The levels of both flavonoids increased over time in the tomatoes that had been grown organically but did not alter significantly in those that had been conventionally produced. The researchers noted that the increasing level of the flavonoids in the organically-grown tomatoes over the 10 year period corresponded with increasing amounts of organic matter in the soil in which those tomatoes were grown, along with a reduction in the manure applied once the soil for the organic tomatoes had reached “equilibrium levels of organic matter.” While the levels of only two antioxidants were measured, and those for just one crop, this study was conducted over a much longer period of time, and the scientists also looked at soil health, a critical aspect of agriculture too often neglected in studies.

For starters, people need to stop regarding vitamins, minerals and antioxidants as substances that will cure all bodily evils, present or potential. Ingesting excessive amounts of any or all of these, regardless of whether their sources are organic or conventional, will not guarantee good health and could even prove harmful. As far as the declaration that organic veggies contain more nutrients because they are slower-growing than conventional counterparts and remain in the soil for a longer time, Dr. Margaret Smith, a Professor in the Department of Plant Breeding and Genetics at Cornell University, says that such claims are made regularly by organic growers. Dr. Smith believes that “…the chemical composition of organic produce might be different because the chemical constitution of the soils in which these plants grow is different.” She also notes that, while she’s not a nutritionist, she has “yet to see any convincing scientific studies showing larger mineral and nutrient content in organic versus non-organic produce.”

So, Should You Switch To Organic Produce?

Economics are frequently a sticking point where organics are concerned. If you’re watching every penny, affording organics may be difficult. Even though many big-chain U.S. grocers now carry them and they are more accessible, you’re going to pay more for organic fruits and vegetables in most cases. How much more? One U.K. study found that organic produce is “typically about 30% more expensive,” and that figure seems to approximate U.S. costs as well. Why? Simple: Organic farming is more costly for the farmer. To begin with, organic certification is an expensive (not to mention time-consuming) process. Organic farming products, whether you’re talking about seeds or sprays, are invariably higher-priced than identical conventional items. Farming organically is more labor-intensive; labor costs time, and time equals money. And organic farming almost invariably results in lower crop yields. Even with the higher prices they charge, it can still be difficult for organic farmers to earn a living wage.

One of the most frequently-cited reasons for purchasing and consuming organic foods is the use, or over-use, of agrochemicals. An astronomical quantity of these chemicals, in synthetic pesticides, as well as in synthetic fertilizers, goes into the growing of conventional fruits and vegetables every year. An increasing number of people are becoming concerned about what effects these agrochemicals, and any run-off from them, may have on soil, groundwater, wildlife, and human health. There’s no better example of the environmental impact of agrochemicals than the annual “dead zone” that forms in the Gulf of Mexico.

Every year, beginning around April, an increasingly-large area in the Gulf becomes so oxygen-depleted that it cannot support any marine life. This is the dead zone, which peaks in size around late July. In 2005, this area was almost the size of the state of New Jersey. One of the chief causes of the dead zone, it turns out, is agricultural fertilizers. Excess nutrients from both synthetic fertilizers and manure drain into the Gulf from the Mississippi and Atchafalya River Basins. There, they cause microscopic phyloplankton to thrive and reproduce in large numbers. When the phyloplankton die, they sink to the ocean’s bottom, where they’re decomposed by bacteria that consume oxygen. Unfortunately, the bacteria also exhaust most of the oxygen in the water, leaving an insufficient amount for other marine life.

By contrast, organic production is distinctly limited in the types of chemicals that are allowed to be used (manure is also allowed in organic production, but there are serious restrictions on how it must be handled). Given that fewer chemicals are used in organic growing, wouldn’t that mean that organic foods are automatically better for the planet?