A single seed of hybrid cherry tomatoes, named Summer Sun.

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Genetically Modified Foods

All livestock share the same basic standards of care in order to be considered organically raised, including humane treatment and living conditions similar to the animals' natural habitat. They are fed a diet of 100 percent organic feed products; they do not receive hormones to promote growth, nor are they given antibiotics for any reason, although they may be given vaccinations as preventative care.

These methods are significantly different from conventional farming methods. Before the 1940s, farms practiced what we'd now consider organic farming methods. However, a revolution in agricultural technologies around the beginning of the 20th century, and specifically after World War II, reshaped the way farmers managed crops; as a result, productivity skyrocketed.

Conventional farmers take advantage of the latest scientific and agricultural technological advances meant for greater efficiency and high output, including chemical and synthetic pesticides and fertilizers, mono-cropping, genetic-engineering and modification (in seeds and breeds) and antibiotic and hormone use in livestock.

Genetically modified crops, also known as GM or GMOs (genetically modified, or genetically modified organisms), are plants with altered DNA, giving them greater resistance to herbicides or improved nutritional content. GM foods were originally intended to reduce disease in crops, leading to larger output at less cost. According to the United States Department of Agriculture (USDA), there are more than 40 plant varieties that have met federal requirements so far.

There are several criticisms of GM foods, including risks to both human health and to our environment. In humans, GM foods are assessed for nutritional content, toxicity levels and any allergic reactions that might occur from eating them. Of concern to the environment is the possibility that a GMO can be introduced into wild populations, with the development of pesticide-resistant insects. Possible detrimental consequences to plant and wildlife biodiversity are also under investigation.

Unlike the strict standards in place for organic farmers, there is no mandate that foods containing GMOs must be labeled as such in the U.S.

At the 12th Scientific Conference of the International Federation of Organic Agriculture Movements (IFOAM) in 1988, more than 60 countries voted unanimously against the use of GMOs in food production and agriculture because they felt there were unacceptable risks involved: threats to human health, a negative and irreversible environmental impact, incompatibility with sustainable agriculture, and a violation of rights for both farmers and consumers.

Growing your own produce can minimize any anxiety you may have about where your food comes from, but not all of us were born with a green thumb. Finding organic products is getting easier, and your local grocery store may be stocking more than you remember seeing last time you looked. Another place where you can feel good about the tomatoes you buy is at your local farmers' market, and depending on where you live, you may be able to join a local co-op or buy a share in a community-supported organic farm. Or, try ordering by mail or online -- some producers will ship.

In the next section, we'll discuss the government standards for organic farming and how organic farmers become certified.