The organic food market has exploded in the last few decades. People choose organic foods for a variety of reasons including fewer pesticides, fresher, better tasting and a belief that they are more nutritious than non organic food. But what does organic really mean? Are they healthier than non organic foods? Do they use pesticides?
Definition of organic farming
US regulations specify that organic food producers cannot use: growth hormones, antibiotics, synthetic pesticides, chemical fertilizers, genetically modified ingredients, or sewer sludge (1). Organic farmers can use natural fertilizers and pesticides (not synthetic). Organic farmers can use synthetic materials if they are in the National List of Allowed and Prohibited Substances (1). Synthetic material is a substance made by a chemical process that chemically alters a substance taken from a plant, animal or mineral source (1). Instead, organic farmers use animal and crop wastes, botanical, biological or non synthetic pest control, and synthetic material that are allowed and which break down quickly by oxygen and sunlight (1).
To convert a conventional farm to organic farm no prohibited substances could have been used on the farm for at least three years (1). Organic operations must be certified by a USDA accredited inspector (1). This certification gives 3rd party assurance that a product was raised, processed and distributed to meet the official organic standards (1).
Controversial organic pesticides
Some of the more controversial organic pesticides include: rotenone, copper, nicotine sulfate, and pyrethrums. Rotenone is a naturally occurring chemical found in the seeds and stems of various plants. In organic farming it is used as a pesticide, insecticide, and as a fish killer. Native peoples have released rotenone into ponds where it interacted with the cellular respiration of fish causing them to go to the surface for air where they were easily caught. Rotenone is currently being phased out for use in organic farming in the United States and Canada. It works by blocking the energy creating pathway called the electron transport chain which causes a back up of electrons which damage DNA.
The World Health Organization classifies Rotenone as “moderately hazardous.” It is mildly toxic to humans and other mammals but extremely toxic to insects and aquatic life. Sunlight causes Rotenone to break down within six days. Studies in mice have shown that rotenone doses below detectable limits have induced Parkinson’s like symptoms in mice and a 2011 study showed a link between Rotenone use and development of Parkinson’s disease among farm workers (2).
This is a plant compound extracted from the daisy flower after it has been ground (3). It kills insects by producing hyperactivity and convulsions. Pure pyrethrum is moderately toxic to mammals at 500 mg but the kind used in agriculture is less toxic and requires 1500 mg to produce negative effects in rats (3). It is also broken down by the sunlight within 2 hours of application.
An insecticide from the seeds of the Indian neem tree. It causes sterility in female insects and interferes with the shell molting of insects. Neem is considered nontoxic to mammals.
The Organic Symbol
The organic symbol means that a product is 100% or 95% organic. Labels “100% Organic,” must use all organic ingredients. The Organic symbol may also be used if a product is 95% organic with the other 5% being from ingredients on the National List of Approved Substances. A label can say “made with organic ingredients,” if the product is made up of at least 70% organic materials.
Naturally occurring toxins from selective breeding
Instead of using genetic modifications, organic farmers rely on selective breeding of plants to confer some benefit such as chemicals found in plants that naturally deter insects. Once they isolate plants with this benefit they breed the plants to increase the likelihood of the future plants having the resistance. Sometimes this practice can result in high levels of natural toxins that are dangerous to humans.
An example of this is the tomato and potato plants which naturally produce glycoalkloids which are chemicals that provide insect resistance. These can be dangerous to humans at high levels which caused the abandonment of a program to breed potatoes with high insect resistance when it was found out that they contained glycoalkloid levels which could cause acute toxicity in humans (1). This was the only example I could find so I assume that these toxins are rarely seen.
Microbiological safety of organic vs. conventional products
Conventional – not organic
Although organic and conventional farming both rely on the use on animal manure as fertilizer organic farmers may rely more heavily on animal manure since they cannot use synthetic fertilizers instead as many conventional farmers do (1). Even if true, this does not automatically mean more microbiological contamination of organic products. One of the few studies on this topic compared levels of Escherichia coli, Salmonella, and Escherichia coli 0157:H7 on organic vs. conventional foods (4).
The study found that none of the samples contained Escherichia coli 0157:H7 while only two samples (organic lettuce and organic peppers) contained Salmonella. Generic E. coli was found in 9.7% of the organic samples and 1.6% of the conventional samples. When using certified organic produce, the 9.7% was reduced to 4.3% which was not significantly different than the rate found in conventional products. When comparing generic E. coli in lettuce, certified organic foods had a 0% infected rate while noncertified organic foods had a 31% infected rate and conventional foods had a 17% infected rate.
The European Union specifies that organic farms must have a lower nitrogen concentration than conventional farms in order to be categorized as organic. Most studies have shown that organic foods consistently have lower levels of nitrates and nitrites than conventional food. Nitrates can easily be converted to Nitrites which cause a dangerous illness in babies, the elderly, and infants called methaemoglobinaemia (5). Another issue is that nitrites are able to react with amines to create nitrosamines which have been shown to be carcinogenic and mutagenic causing leukemia and cancer of the digestive tract (5). On average, switching from conventional to organic foods will lead to a 50% reduction in the intake of dietary nitrates and nitrites (5).
Are Organic foods healthier than conventional?
The research in this area has produced mixed results. Some studies found that organic foods contained more phytochemical than conventional foods while other studies found no difference. I personally think the biggest variables in nutrient composition are the soil type, climate, soil cultivation, fertilizer used and how crops are stored after being picked. I am willing to bet that if similar conventional plants were analyzed from different parts of the country they would differ in their nutritional make up for reasons I just previously mentioned. Even if organic foods have slightly higher levels of phytochemicals it is likely so small as to impart no extra health benefits.
Crop variety in organic farming
Organic farms and conventional farms use different farming methods. Organic farming stresses crop diversity. Benefits from planting many species of plants in the same land include supporting a wider range of beneficial insects, soil microorganisms and it helps the soil remain viable for a longer time. Conventional farming stresses monoculture. This practice stresses only one type of crop per field which overtime depletes the soil and makes it inhabitable to grow plants.
To improve soil fertility organic farming uses a variety of methods including crop rotation, reduced tillage, cover cropping and application of compost. Organic farming stresses maintaining soil fertility for the long term while conventional farming does not. From a sustainability standpoint, organic farming is better for the land and geared more towards making the most use of the land and for the longest period of time.
|Dirty Dozen-high pesticides||Clean 15-low pesticides|
|Sweet Bell Pepper||Eggplant|
|Cherry Tomatoes||Sweet Peas|
|Kale / Collards||Grape Fruit|
People chose to eat organic foods for a variety of reasons. For me I would choose organic foods because they contain fewer pesticides. They are also better for the environment but that does not matter as much to me. Natural does not always mean safe. Metals are perfectly natural but if you consume too much they can be fatal. On the other hand, synthetic or unnatural does not always mean unsafe.
Having said that it seems evident that organic pesticides are less toxic, more degradable and better for the environment than synthetic pesticides. If you have the money I would make all of your food organic. If you cannot afford to buy everything organic try to at least get the food on the above dirty dozen list since they contain the highest amounts of pesticides.
I do not believe that organic foods are inherently healthier than similar conventional foods. I believe most of the health benefits from organic foods come from fewer and less toxic pesticides. One issue is that we import a TON of fruits and vegetables from other countries that may claim a product is organic but it would be difficult for the USDA to check every import for pesticides. That is why it is better to buy from the United States as we have more stringent testing here.
To answer my question in the title – Yes, organic foods are worth the extra money
- Winter, C. K., & Davis, S. F. (2006). Organic foods. Journal of Food Science, 71(9), R117-R124.
- Tanner, C. M., Kamel, F., Ross, G., Hoppin, J. A., Goldman, S. M., Korell, M., … & Langston, J. W. (2011). Rotenone, paraquat, and Parkinson’s disease. Environmental health perspectives, 119(6), 866-872.
- Isman, M. B. (2006). Botanical insecticides, deterrents, and repellents in modern agriculture and an increasingly regulated world. Annu. Rev. Entomol., 51, 45-66.
- Mukherjee, A., Speh, D., Dyck, E., & Diez-Gonzalez, F. (2004). Preharvest evaluation of coliforms, Escherichia coli, Salmonella, and Escherichia coli O157: H7 in organic and conventional produce grown by Minnesota farmers. Journal of Food Protection®, 67(5), 894-900.
- Rembiałkowska, E. (2007). Quality of plant products from organic agriculture. Journal of the Science of Food and Agriculture, 87(15), 2757-2762.