April 2008
Organics: Separating Science Fiction From Fact
By Carol Ann Brannon, MS, RD, LD
Today’s Dietitian
Vol. 10 No. 4 P. 10
Suggested CDR Learning Codes: 2000, 2030, 2040, 2050; Level 2
Can you confidently answer questions about food biotechnology, as well as genetically modified (GM), conventional, and organic foods?
Many consumers are concerned about the potentially hazardous health effects from exposure to pesticides, hormones, and antibiotics used in conventional farming. Most people are less knowledgeable about how rapidly burgeoning technology is changing their food supply, and many have formed opinions about certain types of GM foods without much information about them. Rapid change yields anxiety and increases the potential for misinformation, misunderstanding, and exploitation. Dietitians must provide consumers with reliable, factual information and are uniquely positioned to help them separate food science fiction from fact.
Foods and Farming
Agriculture, food, nutrition, and health are intimately intertwined and interrelated. Agriculture is a vast, diverse, and complex enterprise shaped by social, political, economic, and environmental policies. Knowledge about the past is necessary to fully appreciate the present and future.
From 1900 to 1950, Americans relied largely on family-operated farms for their food supply, and food availability was limited. The dietary intake and nutritional status of many Americans were poor, as reflected by the prevalence of deficiency diseases. Americans, especially those with low income levels, were considered underweight. Infectious diseases (tuberculosis, pneumonia, and diarrhea) were the leading causes of death.1,2
Approximately 50 years ago, large-scale farming and livestock operations replaced family-operated farms. The use of pesticides, synthetic fertilizers, hormones, and antibiotics became routine. Increased agricultural productivity; advances in food processing, storage, and transportation; and global trade have resulted in an abundant and diverse U.S. food supply. Fortification of foods has contributed to a phenomenon unthinkable throughout most of human history: overnutrition.1,3
At the same time, the promotion of inexpensive processed foods has made these products increasingly popular. Their growth is linked to the obesity epidemic and the prevalence of chronic diseases such as diabetes, heart disease, and cancer, as well as asthma, allergies, autism, and attention-deficit/hyperactivity disorder (ADHD) in children. The leading causes of death are now heart disease and cancer.1,4
Changes in our food supply and eating habits have produced stricter food labeling laws, and the prospect of our ability to produce foods not found in nature has prompted concern for more and better regulation. The U.S. food supply is regulated by the FDA, the USDA, and the U.S. Environmental Protection Agency (EPA). The mission of all three agencies is to ensure a safe food supply; however, each agency defines and approaches food safety from a different perspective.1 None are perfectly positioned to monitor and regulate what have become known as millennium foods, an umbrella term that encompasses a variety of genetic engineering techniques and biological systems (microbes, plants, and animals).1
Crossbreeding and gene splicing are two examples of biotechnology. For centuries, farmers have been crossbreeding, or combining genes from two different plants to form a new variety. Crossbreeding was tedious and time consuming but yielded a new, superior plant.1,5
There’s nothing new about genetic engineering, but what is new is the ability to micromanage genes for a desired effect. Genetic modification involves the manipulation of DNA through the removal, insertion, or splicing of genes from different organisms, creating a new DNA molecule called recombinant DNA (rDNA).1,5-7
rDNA technology allows specific genes to be moved from one species or kingdom and inserted into another. For example, a gene from a bacterium could be isolated and inserted into a plant, producing a new combination of genetic traits that do not and cannot occur in nature.1,5
Nutritional values can be enhanced through GM. Fruits and vegetables can be made higher in antioxidants, and cooking oils can contain less saturated fats. For example, “golden rice” is rich in vitamin A due to the insertion of beta-carotene–producing genes into the rice grains. Although it is expected to be a few more years before it is commercially produced, it is already considered a miracle food in developing Asian countries where rice is a dietary staple and diets are severely deficient in vitamin A. Approximately 300 million children suffer from stunted growth and blindness secondary to vitamin A deficiency.6 More alarming is that vitamin A deficiency is responsible for 1 to 2 million deaths per year.9
Currently, a variety of GM foods and animal feeds are allowed in the American market, including alfalfa, corn, canola, chicory, flax, papayas, potatoes, soybeans, squash, sugar beets, and tomatoes. As of 2000, there were at least 50 GM products. Soybean and corn are the most common transgenic crops, followed by cotton, canola oil, and potatoes. Seventy-five percent of soybean crops and 34% of corn crops were genetically modified in 2002.1,7
Agricultural biotechnology is regulated by the EPA and the USDA. The position of the U.S. regulatory agencies is that there is no need for a GM label since these foods and ingredients are considered safe.1 However, that view point is not shared worldwide, and there are vocal critics calling attention to human health and environmental concerns. There are two major issues: GM foods may contain antibiotic-resistant genes that could be picked up by bacteria, which in turn may infect us, and GM foods may contain unseen and unknown food allergens.1,8-13
The long-term environmental consequences of GM foods are unknown. And while U.S. farmers have embraced GM seeds, advocacy groups are alarmed that they have embarked down a slippery slope where mistakes that cannot be corrected are possible. In an environment where food irradiation, fortification, and creation of whole new “designer” foods are progressing at breakneck speed, there is a sense that things have gone too far too fast.9 Consumers who agree have one choice: buy organic.
Because there are no GM labeling requirements, many consumers may not know the extent to which their diet includes GM foods. Organic foods are currently the only foods guaranteed not to include GM ingredients.1,8-13
Organic farmers emphasize the use of renewable resources and value soil and water conservation, seeking to preserve the “cycle of life” by relying on interdependence between soil, plants, animals, and humans. Chemical pesticides, fertilizers made with synthetic ingredients or sewage sludge, bioengineering, and ionizing radiation are excluded. There are thousands of pesticides that include naturally derived and synthetically produced substances. In addition, pesticides can include organisms. For example, the bacterium Bacillus thuringiensis is used to offer protection from selected insects. A gene from this bacterium can be implanted into a plant seed so that the plant becomes resistant to selected insects.9 In organic farming, the use of companion planting, beneficial insects, and natural soil replenishment is stressed. Organic farming, once the only farming method, was largely subsumed by the industrialization of the food supply, but it became more fashionable in the 1960s and 1970s and is now a thriving industry.1
Organic is now understood to mean “produced without the use of most conventional pesticides, fertilizers made with synthetic ingredients or sewage sludge, bioengineering, or ionizing radiation.” But the road to that understanding was twisted. In 1995, the National Organic Standards Board defined organic as a labeling term denoting products made under the authority of the Organic Foods Production Act of 1990. It states, “Organic agriculture is an ecological production management system that promotes and enhances biodiversity, biological cycles, and soil biological activity. It is based on minimal use of off-farm inputs and on management practices that restore, maintain, and enhance ecological harmony.”1,14,15 There was no mention of genetic engineering, cloning, or irradiation.
In 1998, the USDA proposed the development of national standards that would allow the use of GM ingredients, sewage sludge, and irradiation in organic food production. This was met with serious consumer resistance, with more than 200,000 negative comments received, causing the USDA to withdraw the proposal. In December 2000, the USDA released another proposal that excluded GM ingredients, sewage sludge, and irradiation from the organic standards. These standards went into effect in October 2002.14
Organic fruits and vegetables are farmed with botanical or primarily nonsynthetic pest controls that are quickly broken down by sunlight and oxygen, unlike long-lasting synthetic chemicals. Organic produce may sometimes carry chemical residues due to conventional pesticide residues still pervasive in groundwater and rain. Regardless, organics have less chemical residues than conventional produce.14
Organic meat, poultry, eggs, and dairy foods come from animals not given antibiotics or growth hormones. The philosophy of organic livestock production is to provide conditions that meet the health needs and natural behavior of the animal: access to the outdoors, fresh air, water, sunshine, and pasture. Organic livestock must be fed 100% organic feed, free of any animal by-products, hormones, antibiotics, or other drugs. If an organic animal gets sick and is given antibiotics, its meat, milk, or eggs cannot be marketed as organic. Certified organic farmers must keep extensive records to trace the animal from birth to the market.1,14,15
Labeling laws reassure consumers. Produce, meat, poultry, eggs, and dairy products bearing a green and white organic seal have met stringent USDA standards and passed inspection. If labeled “100% organic,” the product has no synthetic ingredients; if labeled “organic,” it has a minimum of 95% organic ingredients. Both may use the USDA organic seal. Food labeled “made with organic ingredients” must contain at least 70% organic ingredients but may not use the seal.14
As we’ve seen with supplements, strict definitions are important. The terms free range, hormone free, or natural are not synonymous with organic. The term natural broadly refers to minimally processed foods that are free of synthetic preservatives, artificial additives, hydrogenated oils, stabilizers, and emulsifiers. The term natural is not regulated, but the USDA allows this term for products that have been minimally processed, do not differ fundamentally from the raw product, and contain no artificial ingredients, such as carrageenan or monosodium glutamate. The majority of raw meat and poultry found in grocery stores fits this definition. Natural does not mean hormone or antibiotic free.16
Superior Nutrition?
Though they satisfy consumer concerns about potential environmental and health risks, organic foods are not guaranteed safer, healthier, more nutritious, or more flavorful than conventional foods. While many believe that organic produce is superior in nutrition to conventional produce, this has been difficult to prove because of the difficulty in controlling all variables (eg, soil quality and condition, maturity at harvest) that could influence nutrient content. Diversity in local soil conditions is an important variable. Thus, definitive scientific conclusions cannot be made.17 However, a small number of studies indicate that organic produce has a greater mineral content than conventional produce, possibly related to the use of organic fertilizers (compost or manure).1
Organic products may offer health benefits beyond those associated with mineral content. Organic fertilization grows plants with lower levels of nitrogen and nitrate. Dietary nitrate has long been considered harmful because it can be metabolized to nitrite, which can be combined with amines (from protein) to form nitrosamines in the presence of stomach acid. There is a link between nitrosamines and cancer development in animals.1 However, some argue that nitrate is beneficial because when it is converted to nitrite in the presence of gastric acid, it becomes acidified and acquires antimicrobial properties.18,19
In addition, there appears to be an inverse relationship between nitrogen and phenolic compounds in plants. The lower a plant’s nitrogen content, the higher its content of phenolic compounds, a category of phytochemicals with strong antioxidant, anti-inflammatory, and anticlotting properties. More research is needed to clarify the effect of organic farming practices on human health.18,19
What about taste? Consumers of organic foods are adamant that the flavor and freshness, especially of locally grown produce, are superior to conventional foods.17 Obviously, no proof is possible; taste is a matter of taste.
Safety
According to the Organic Trade Association, organic products are as safe as conventionally produced foods. Certified organic farmers must adhere to strict guidelines for safe and hygienic food production, as well as comply with all local, state, and federal health standards.14-16
All foods have the potential of being contaminated with harmful bacteria. To ensure the safety of organic foods, diligence should be exercised in properly washing produce and hands and in adhering to safe food storage and cooking practices. Whenever possible, consumers should know where the food they are buying originated.
The government has established “safe” limits regarding the amount of pesticides that can be used in conventional farming. Organophosphates, known to be neurotoxins, are the most common class of U.S. pesticides. A growing body of research indicates that pesticides and other contaminants are more prevalent than originally thought and may pose a health risk. Studies have shown that most conventionally grown produce has residues that are within the allowable limits set by the EPA. The consumption of organic foods limits exposure to pesticide residues.1,14,15
Organic crops must be produced without the use of pesticides; however, an estimated 10% to 25% of organic fruits and vegetables contain some residues of synthetic pesticides because of the influence of rain, air, and polluted water sources. To qualify as organic, crops must be grown in soil free of prohibited substances for three years before harvest. If traditional organic farming methods fail to control pests, farmers can request permission from the National Organic Standards Board to use certain low-risk pesticides.1,15
Young children have immature immune systems and may be at risk from even minor exposure to pesticides.4,20 A 2002 study found that children aged 2 to 5 who ate conventionally grown food had 8.5 times more organophosphate residue in their urine than children who ate organic foods. New studies are emerging suggesting that pesticides, particularly the organophosphate insecticide chlorpyrifos (currently used on corn, soy, wheat, and many fruits and vegetables), and other persistent organic pollutants are linked to ADHD, obesity, diabetes, and learning disorders.20 More research is needed before decisive conclusions can be drawn.
The safety of bovine growth hormone (BGH) and bovine somatotropin (BST) residues is controversial and hotly debated. These hormones are produced for commercial use using rDNA technology, causing them to be identified as rBGH and rBST. Currently, rBGH is used to increase the weight of beef and dairy cattle by roughly 10% while rBST is given to dairy cows to increase milk production by approximately 10%.1
There is strong debate regarding the safety of these hormones. Bovine hormones contained in meat or milk from cattle administered rBGH or rBST cannot survive in the digestive tract and do not appear to be absorbed by the human digestive tract. However, the use of rBST in dairy cattle increases their production of insulinlike growth factor 1 (IGF-1). The IGF-1 in cow’s milk is absorbed by humans and appears to accumulate in breast cells where it stimulates growth. Although women with breast cancer have high levels of IGF-1, no studies have found a direct link between IGF-1 and breast cancer. After extensive review, the FDA concluded that rBST posed no appreciable risk and approved its use.1
The risk of mastitis is higher in dairy cows given rBST, so cows receive antibiotic therapy to treat the mastitis. Milk from cows administered rBST contains residual antibiotics. After an extensive review, the FDA approved the use of both rBGH and rBST, but Health Canada (a counterpart of the FDA) approved only the use of rBGH. Given the facts, consumers can decide whether they will drink or use conventionally produced milk or organic milk.1,21
Farm animals receive 24.6 million pounds of antibiotics per year. Today, approximately 70% of antibiotic use is to fatten livestock. Public health authorities now link low-level antibiotic use in livestock to the increased number of people contracting antibiotic-resistant infections. The treatment these infections are resistant to is the same antibiotics given to livestock. In June 2001, the American Medical Association adopted a resolution opposing the use of subtherapeutic levels of antibiotics in agriculture. Likewise, in a 2001 report, the World Health Organization urged farmers to stop using antibiotics for growth promotion.1,21
Conventional, Biotech, or Organic?
Is the absence of evidence evidence of absence? If you can’t prove harm, does that prove safety? Opponents of pesticides, synthetic fertilizers, antibiotics, hormones, and GM foods say no. Statements such as, “There is no conclusive evidence of harm to humans” from exposure to pesticide X may be true, but it misleads the public into believing that exposure to pesticides is without risk. Risk is relative to each individual.1 For example, the parent of a child with multiple food allergies may decide that the potential risk of GM produce is too great for the child. Such decisions have transformed organic foods from a small niche market into a significant sector of the grocery market, with annual sales in the billions.14,22,23
The demographics of this market reflect a generational focus. Thirty-two percent of organic shoppers reported that the first time they purchased organic foods was for an infant or child. Many parents are willing to pay approximately 30% more for organic baby food, and although it represents only a small market segment, it is rapidly growing. Gerber Products Company replaced its Tender Harvest brand with an expanded product line called Gerber Organic to make it more obvious that these foods are organic. Abbott Nutrition has introduced Similac Organic Infant Formula because of market demand.22
The demographics of this market reflect a generational focus. Thirty-two percent of organic shoppers reported that the first time they purchased organic foods was for an infant or child. Many parents are willing to pay approximately 30% more for organic baby food, and although it represents only a small market segment, it is rapidly growing. Gerber Products Company replaced its Tender Harvest brand with an expanded product line called Gerber Organic to make it more obvious that these foods are organic. Abbott Nutrition has introduced Similac Organic Infant Formula because of market demand.22
Baby boomers, those aged 44 to 62, represent a large percentage of organic food consumers. They are more likely to buy locally produced foods and want to eat healthy and live long, strong, and well.23 They also have money to indulge their preferences. While most people believe that organic foods are healthier, their higher cost is a deterrent. Organic foods cost an average of 50% more than conventionally grown produce. Nonetheless, organic food sales are increasing and are no longer available only in health food stores. Comparative shopping and purchasing “in-season” produce will help keep personal food budgets in line.24
All experts agree that whether you buy organic or conventional foods, you should:
• Buy local produce whenever possible.
• Reduce pesticide residues and other contaminants on foods by:
- washing and scrubbing all produce (even produce with inedible skin) under streaming water (do not use soap);
- removing the peel from fruits and vegetables;
- removing the outer leaves of leafy vegetables;
- discarding cut produce if it has been out of the refrigerator for four hours or more; and
- trimming visible fat and skin from meat and poultry, as pesticide residues can collect in fat.
• Eat a variety of foods from different sources.
• Prioritize. The majority of your organic food dollars should be spent on produce since it is most likely to contain the most pesticides. Table 1 lists the “dirty dozen,” or the produce most susceptible to pesticide residue, and the produce least susceptible, the “not-so-dirty dozen.”24
Two things are certain: Progress will continue in food technology, and our ability to understand and assess the impact of that progress will improve. In a world with a steadily growing population, it is hard to argue against techniques that make more, nutritionally better food available to more people, especially if the reasons for doing so are ideological rather than scientific. However, risk assessment must always be an important part of the equation.
— Carol Ann Brannon, MS, RD, LD, is a consulting dietitian at Fowler YMCA and in private practice in Georgia.
Produce’s “Dirty Dozen” (highest in pesticide residue)
Peaches
Apples
Sweet bell peppers
Celery
Nectarines
Strawberries
Cherries
Pears
Grapes (imported)
Spinach
Lettuce
Potatoes
Produce’s “Not-So-Dirty Dozen” (lowest in pesticide residue)
Papayas
Broccoli
Cabbage
Bananas
Kiwi
Sweet peas (frozen)
Asparagus
Mangoes
Pineapple
Sweet corn (frozen)
Avocados
Onions
Learning Objectives
After completing this module, the student will be able to:
1. Explain the concept of overnutrition.
2. List and discuss the roles of regulatory agencies in overseeing the U.S. food supply.
3. Define genetic modification and give examples of its use.
4. Explain the rationale for the U.S. government’s labeling policy for genetically modified foods.
5. Discuss the relative risks of pesticides in plant foods and antibiotic residues in animal food products.
Examination
1. In the United States between 1900 and 1950, which factor accounted for the three leading causes of death?
a. Overnutrition
b. Chronic disease
c. Infectious disease
d. Industrial accidents
e. Environmental contaminants
2. Regulation of a safe food supply is overseen by:
a. the FDA only.
b. the USDA only.
c. the FDA and the USDA.
d. the Environmental Protection Agency (EPA).
e. the FDA, the USDA, and the EPA.
3. “Golden rice” is an example of a genetically modified food and a rich source of:
a. monounsaturated fatty acids.
b. lycopene.
c. beta-carotene.
d. iron.
e. high biological value protein.
4. The most common genetically modified (GM) crops in the United States are:
a. corn and wheat.
b. corn and soybeans.
c. soybeans and wheat.
d. citrus fruit and tomatoes.
e. rice and corn.
5. Which of the following is true about the labeling of GM food in the United States?
a. The FDA and USDA require all GM food to be labeled.
b. The circle symbol with GM is on the label.
c. “Grown from genetically modified seed” must be printed at least as large as the ingredients.
d. GM foods are considered safe and not required to be labeled in the United States.
e. a and c
6. A client wishes to avoid GM foods. What is the best advice that you can give?
a. Buy foods that are labeled all natural.
b. Buy foods that are certified organic.
c. Buy foods that are labeled GMO rather than GM.
d. Avoid corn and soybeans because those are the only GM seeds used in the United States.
7. What is the primary reason that antibiotics are added to cattle feed?
a. To treat infections in cattle
b. To prevent infections in cattle
c. To fatten cattle
d. To prevent contamination by Escherichia coli in slaughtered cattle
e. None of the above
8. The American Medical Association issued a resolution opposing the use of subtherapeutic levels of antibiotics in dairy cows.
a. True
b. False
9. Which of the following are the most pesticide-intensive crops?
a. Strawberries, carrots, and cabbage
b. Almonds, bananas, and kiwi
c. Wheat, rice, and barley
d. Cow’s milk
e. Eggs
10. Pesticide residues on conventionally produced foods:
a. are regarded as safe by the FDA.
b. may pose a health concern or risk for young children.
c. are considered neurotoxins.
d. are more prevalent than once thought.
e. all of the above
References
1. Dunford M. Technology, Food, and Nutrition. Ashland, OR: Nutrition Dimension Inc.; 2006.
2. Cohen ML. Changing patterns of infectious disease. Nature. 2000;406(6797):762-767.
3. Backstrand JR. The history and future of food fortification in the United States: A public health perspective. Nutr Rev. 2002;60(1):15-26.
4. Bock K, Stauth C. Healing the New Childhood Epidemics: Autism, ADHD, Asthma, and Allergies: The Groundbreaking Program for the 4-A Disorders. New York: Ballentine Books; 2007.
5. Vento AB, Gillum DR. Fact sheet describing recombinant DNA and elements utilizing recombinant DNA such as plasmids and viral vectors, and the application of recombinant DNA techniques in molecular biology. Office of Environmental Health and Safety. University of New Hampshire. June 3, 2002. Available at: http://www.unh.edu/ehs/pdf/Recombinant-DNA.pdf
6. Yan L, Kerr PS. Genetically engineered crops: Their potential use for improvement of human nutrition. Nutr Rev. 2002;60(5 Pt 1):135-141.
7. Pew Initiative on Food and Biotechnology. US vs. EU: An examination of the trade issues surrounding
genetically modified food. December 2005. Available at: http://www.pewtrusts.org/uploadedFiles/wwwpewtrustsorg/
Reports/Food_and_Biotechnology/Biotech_USEU1205.pdf
8. Taylor SL, Hefle SL. Will genetically modified foods be allergenic? J Allergy Clin Immunol. 2001;107(5):765-771.
9. Tarverne D. The real GM food scandal. Prospect Magazine. 2007;140. Available at: http://www.prospectmagazine.co.uk/pdfarticle.php?id=9876
10. Tester M. Seeking clarity in the debate over the safety of GM foods. Nature. 1999;402(6762):575.
11. IFT Expert Report on Biotechnology and Foods. Benefits and concerns associated with recombinant DNA biotechnology-derived foods. Food Tech. 2000;54(10):61-80.
12. Leeder SR. Genetically modified foods—food for thought. Med J Aust. 2000;172(4):173-174.
13. Pelletier DL. Science, law, and politics in FDA’s genetically engineered foods policy: scientific concerns and uncertainties. Nutr Rev. 2005;63(6 Pt 1):210-223.
14. Food Marketing Institute. Natural and Organic Foods. FMI Backgrounder. June 2007. Available at: www.fmi.org/media/bg/natural_organic_foods.pdf
15. Organic Trade Association. The past, present and future of the organic industry: A retrospective of the first 20 years, a look at the current state of organic and forecasting the next 20 years. 2005. Available at: www.ota.com/pics/documents/Forecasting2005.pdf
16. Agricultural Marketing Service, U.S. Department of Agriculture, National Organic Program. Organic food standards and labels: The facts. Updated January 2007. Available at: http://www.ams.usda.gov/nop/Consumers/brochure.html
17. Bourn D, Prescott J. A comparison of the nutritional value, sensory qualities, and food safety of organically and conventionally produced foods. Crit Rev Food Sci Nutr. 2002;42(1):1-34.
18. Magkos F, Arvaniti F, Zampelas A. Organic food: Buying more safety or just peace of mind? A critical review of the literature. Crit Rev Food Sci Nutr. 2006;46(1):23-56.
19 McKnight GM, Duncan CW, Leifert C, Golden MH. Dietary nitrate in man: Friend or foe? Br J Nutr. 1999;81(5):349-358.
20. Beyond Pesticides/National Coalition Against the Misuse of Pesticides. Persistent pesticides linked to ADHD, obesity, and diabetes. School Pesticide Monitor. 2007;7(1):1-2.
21. The Humane Society of the United States. Factory Farming Campaign. An HSUS report: Human health implications of non-therapeutic antibiotic use. March 12, 2007. Available at: www.hsus.org/farm/resources/research/pubhealth/human_health_antibiotics.html
22. Associated Press. Organic baby food a hit with green parents. April 24, 2007. Available at: www.msnbc.msn.com/id/18296482
23. Hughes K. From organic and natural to fair trade: Foods produced with ethical considerations in mind, such as fair trade products, are on a fast growth track. Prepared Foods. May 2006. Available at: www.findarticles.com/p/articles/mi_m3289/is_5_175/ai_n16373451
24. Rose A. Organic foods: Pesticides, GMOs, food irradiation, and eating well an a budget. HelpGuide.org. Available at: www.helpguide.org/life/organic_foods_pesticides_gmo.htm
