(article, Tracy Ilene Miller)
It's not enough anymore to say that organic food is pesticide-free; it's clearly also nutritionally superior. The latest research — including a 10-year study conducted by researchers at the University of California, Davis — is demonstrating that organically grown produce has much higher levels of antioxidants and other nutrients than conventionally grown vegetables and fruits. In the past, comparisons between organic and conventionally grown produce were difficult (and often marginalized) because of the logistical challenges: standardizing growing conditions at two farms (organic and conventional) to statistically compare soil health and irrigation and harvest practices. But the 10-year Davis study, among others, has accomplished this standardization. And the results are undeniable: the organic tomatoes studied by the Davis researchers had far higher levels (79 percent and 97 percent, respectively) of two flavonoids, quercetin and kaemperferol, than the conventional tomatoes. The Davis tomato study comes on the heels of another Davis study showing that organically grown kiwis contain more vitamin C and anthocyanins (disease-fighting compounds) than conventionally grown kiwis. And a series of recent studies from Britain, France, and Poland have shown that organic tomatoes, apples, and peaches have more vitamins and minerals, from Vitamin C to beta-carotene to polyphenols, than conventionally grown produce. Consumers have long clamored for organic produce not just because it's pesticide-free but because it tastes better. Flavor comes from nutrients, and the way in which organic produce is grown — with organic matter continuously being added back to the soil — prevents overfertilization, which actually inhibits nutrient uptake by plants. And a 2004 Davis study reported that the use of pesticides and herbicides also inhibits the production of cancer-fighting polyphenols. Conventionally grown produce is also coming up short in the nutrition department, even against itself. Long-term studies have documented that conventional produce is less nutritious than vegetables and fruit grown on conventional farms even just 50 years ago. The mineral content of conventionally grown food in both the United States and abroad declined in the period after World War II, when government surpluses of ammonium nitrate led to a boom in use of this cheap, synthetic fertilizer. Science, it seems, may have finally caught up with common sense.