Organic food is produced according to a variety of standards and practices that strive to recycle resources and to be ecologically sound. Production, importation and sale of organic foods is increasing rapidly in the U.S. reaching nearly 5% of food sold and valued at $43.3 billion in 2015. Typically, organic food is produced without the use of certain pesticides and fertilizers that are considered or known to be environmentally harmful and they are not processed with food additives or genetically modified ingredients. However, under U.S. federal organic standards, if pests and weeds are not controllable through natural management practices, or by organic pesticides and herbicides, "a substance included on the National List of synthetic substances allowed for use in organic crop production may be applied to prevent, suppress, or control pests, weeds, or diseases." Livestock must be fed certified organic food that contains no animal byproducts, have liberal access to pasture and the use of antibiotics (except for illnesses) or growth hormones is not allowed. Avoiding use of antibiotics reduces the chance of developing dangerous antibiotic resistant “super bugs.”
Organic vs "Natural" or "All Natural" Foods
Because organic food production restricts the use of certain chemical fertilizers, herbicides and pesticides there is the perception that it may be safer, healthier and better for the environment. It is generally not recognized by the public that edible plants have evolved natural pesticides as a defense against insects and other hazards and exposure to natural pesticides is usually much greater than the total daily exposure to synthetic pesticide residues. Because the toxicology of natural and synthetic chemicals is similar, and the human body detoxifies these chemicals similarly, the scientific case for an advantage for the health and safety of organic foods over those produced with conventional farming methods is far from conclusive. A 2012 meta-analysis noted that "there have been no long-term studies of health outcomes of populations consuming predominantly organic versus conventionally produced food controlling for socioeconomic factors; such studies would be expensive to conduct." The American Cancer Society has stated that no evidence exists that the small amount of pesticide residue found on conventional foods will increase the risk of cancer, though it recommends thoroughly washing fruits and vegetables. They have also stated that there is no research to show that organic food reduces cancer risk compared to foods grown with conventional farming methods.
Organic foods also appear to provide little advantage with regard to taste, or nutritive value, or freedom from harmful bacteria. Several systematic reviews have found that organically produced foodstuffs are not significantly richer in vitamins and minerals than conventionally produced foodstuffs. One such review concluded that "there is no good evidence that consumption of organic food is beneficial to health in relation to nutrient content."
Other recent reviews have been more positive about possible benefits of organic foods noting that although there is little evidence of beneficial effects on human health, animal studies have found that there are positive effects of an organic diet on weight, growth, fertility indices and immune system. In addition, human epidemiological studies associated consumption of organic foods with lower risks of allergies and decreased exposure to pesticide residues. Some studies have found that there is neurotoxicity associated with pesticides in farmworker communities including subtle but important effects on neurological development including reduced IQs. 
Although more costly than conventionally produced foodstuffs, organically produced foods may offer some advantages if they are fresh or minimally processed. Organic produce contains fewer pesticide residues than does conventional produce so consuming a diet of organic produce reduces human exposure to pesticides and, in keeping with the precautionary principal that is desirable. But the value of such a reduction in exposure to human health remains uncertain. Organically produced foods are also likely to be better for the environment than those produced by conventional farming practices and undoubtedly they contribute to animal welfare.
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