meta-analysis of the benefits of organic food was released July 11, 2014 open source by the authors and will be published in the British Journal of Nutrition on Tuesday. The study from Newcastle University in the United Kingdom team included one American, Charles M. Benbrook an agricultural economist from Washington State University. The study looked at 343 peer-reviewed publications comparing the nutritional quality and safety of organic and conventional plant-based foods, including fruits, vegetables and grains. The study team applied the most current meta-analysis techniques to quantify differences between organic and non-organic foods.
According to Dr. Benbrook the researchers found that (1) organic crops have, on average, higher levels of antioxidant than conventional crops (on average 17% higher), (2) organic crops have lower cadmium levels than conventional crops, and (3) pesticide residues are present much more frequently in conventional crops than organic ones. Whether these findings would translate into better health outcomes from the long term consumption of organic food is not known. There have never been long-term dietary intervention studies on organic food; the duration of the studies involving human subjects ranged from two days to two years.
While there have been studies that have found an association between some antioxidants and decreased risk of cardiovascular diseases, neurodegenerative diseases and certain cancers, there is no evidence of a causal link. According to Dr. Benbrook antioxidants protect our cells against the effects of oxidation. While oxidation is a normal chemical process that takes place in the body, it can be accelerated by many factors, such as exposure to UV light, exposure to pollution, stress, processed food, and smoking. The oxidation process can trigger the formation of free radicals, which can damage cells in the body and trigger diseases.
A Stanford University meta-analysis study published in 2012 found little significant difference in health benefits between organic and conventional foods. No consistent differences were seen in the vitamin content of organic products, and only one nutrient — phosphorus — was significantly higher in organic versus conventionally grown produce (and the researchers note that because few people have phosphorous deficiency, this has little clinical significance). There was also no difference in protein or fat content between organic and conventional milk, though evidence from a limited number of studies suggested that organic milk may contain significantly higher levels of omega-3 fatty acids.
There are health and environmental risks associated with pesticide exposure. Even at low doses, pesticides can act as an endocrine disruptor and can pose development risks to infants and children. Developmental and other health risks are higher for infants and growing children, because children eat more relative to their body weight than adults, and a child’s organs are less efficient in detoxifying pesticides than adults. Exposure to pesticides for women and men of reproductive age can undermine reproductive health and may increase the risk of spontaneous abortions, certain birth defects, and undermine long-term neurological health of the child. In addition, pesticides can impact the environment and other animals.
Organic food sales in the United States have grown to more than $28 billion in 2012. Traditionally, before the government stepped in to regulate the market, organic foods were grown under “natural conditions” (without the use of inorganic fertilizers, pesticides, or herbicides; and either not processed, or processed without the use of additives) there is now an industrial organic food complex. You may think that you intuitively know what organic means; however, under standards adopted by the U.S. Agriculture Dept. (USDA) in 2000 there is a legal definition. Organic food is food grown, raised and processed without synthetic fertilizers and pesticides, and antibiotics may not be used in raising organic foods. In addition, the use of irradiation, biotechnology, and sewer-sludge fertilizer is also banned. Food whose ingredients are at least 95% organic by weight may carry the "USDA ORGANIC" label; products containing only organic ingredients are labeled 100% organic. So now you have certified organic processed junk food.
However, organically produced food is not entirely free of pesticide residues. A large, high-quality U.S. Department of Agriculture database reports pesticide residues in several dozen organic and conventionally grown foods on an annual basis. A study was performed to evaluate the presence of synthetic pesticides in Organic food and found while organic food significantly reduces pesticide exposure, organic farming does not eliminate pesticide risk. Risk levels arising from pesticide residues in organic food differ by over 1,000-fold, with most posing very modest risks and a limited number associated with possibly worrisome exposure levels.
Most pesticides in organic food tested by the USDA were detected at very low levels and were assumed to be incidental and inadvertent from pesticide drift, pesticide carry over in soil, contaminated compost or organic soil amendments, and contamination of irrigation water. Drift is a widely recognized environmental problem. Aerial application, air blast sprayers, and micro-droplets are application technologies that increase the risk of drift from conventional crops. Legacy contaminants in soil were another cause of pesticides, and without testing the soil it is not possible to predict what levels of contaminants will occur in crops. Not much can be done in the immediate future about legacy contaminants, although organic farmers can avoid problems by planting crops not prone to the uptake of legacy chemicals bound to the soil. More than a third of the pesticide contamination was found to be caused by post-harvest pesticides picked up when the food was processed, packaged etc. Most pesticides in organic food tested by the USDA program were detected at very low levels.
Organic food offers consumers fruits, vegetables and grains that dramatically reduces dietary exposure to pesticide residue compared to industrial farming. There are low use pesticide farming practices that also reduce pesticide exposure. In addition, total antioxidant levels were a 17% higher in organic versus the conventional crops. The levels for much greater — 69% higher levels of flavanones, 28% higher levels of stilbenes, 50% higher levels of flavonols, and 51% higher levels of anthocyanins. Whether this will have any impact on long term health is not known. Also, organic foods were found to have higher levels of phosphorus, but similar levels of vitamins to conventional food. Cadmium exposure is reduced in organic food.
Putting the information together from all these studies I still believe that organic practices are good for the planet, but so are modern conservation farming practices. I am sticking with my mix of organic and conservation farming produced food from my neighbors whose farming practices I know. I avoid distribution networks and food processing exposures to pesticides and everything is fresh.