Archive for September, 2009
This Hot Topic was developed by the Hunger and Environmental Nutrition DPG and is a reflection of the expertise and opinion of HEN DPG members. Hot Topics are short, concise practice and science-based answers to current questions RDs and DTRs may receive. Hot Topics are not an ADA position or stance on a topic and does not reflect Association consensus on the issue. Rather, they provide expert opinion to an emerging area of food, nutrition and health. Hot Topics are meant to assist RDs and DTRs in answers questions of patients/clients and the media. Date of Release: September 2009.
Claim of Topic:
Registered dietitians (RDs) and dietetic technicians (DTRs), registered should fully understand all of the factors consumers must grapple with when making the choice to purchase organic foods, as well as to support future research that will further clarify the differences and costs associated with organically versus conventionally produced foods.
Organic foods are increasing their presence in the marketplace. According to a 2009 Organic Trade Association survey, sales of organic food in the US have grown by almost 16 percent in 2008 over 2007, totaling $22.9 billion in 2008 sales; 3.5 percent of all US food sales (1). These foods are produced following practices described in the USDA National Organic Program (NOP), a marketing program with a certification process throughout the production and manufacturing chain (2). The NOP describes the practices that are required for labeling a product “organic,” but it does not address nutritional benefits or food safety issues (2).
Organic foods are generally more expensive in the marketplace than conventional foods, due in part to their smaller production scale and higher labor costs (3). However, organic produce purchased in-season is usually comparable in price to conventional produce (4). In addition, community supported agriculture programs can provide low-income consumers with access to fresh, organic produce that may be difficult to find in some urban locations (5). Research also shows consumers are willing to pay a price premium for some organic food products in the marketplace, including certain fruits and vegetables (6).
When considering benefits and costs of organic versus conventional agricultural production, it is important to consider benefits and costs to consumers, farmers, communities and the environment (3, 7, 8). For example, current research in numerous areas is showing both short-and long-term benefits to our population and the planet with organic and other sustainable production systems. Documented environmental benefits of organic production systems include reduced nutrient pollution, improved soil organic matter, lower energy use, reduced pesticide residues in food and water and enhanced biodiversity (3).
Whether or not organically produced foods are more nutritious than their conventionally produced counterparts is the subject of an ongoing debate. One recent review of the nutritional quality of organically versus conventionally produced food reported organically produced plant products contained more dry matter and some minerals (iron, magnesium) and more antioxidants such as phenols and salicylic acid than conventionally produced plant products(9). In contrast, a recent systematic review found no evidence of a difference in nutrient quality between organically and conventionally produced food, except for nitrogen (which was significantly higher in conventionally produced crops) and phosphorus and titratable acidity or ripeness at harvest (which were significantly higher in organically produced crops) (10). In this systematic review, the authors did not examine differences in contaminants (such as pesticide, herbicide or fungicide residues) or the possible environmental consequences of organic versus conventional production practices (10).
Discussion of Topic:
Consumers report cost, health and environmental concerns as factors in considering their decision to purchase foods labeled organic (1, 11). In juxtaposition to conventional foods, there are a variety of reasons why organic foods can be considered as facilitating the creation of a healthful, sustainable food system.
1. Some organic fruits, vegetables and juices may contain more phytochemicals (e.g., antioxidants and polyphenols) compared to their conventionally grown counterparts (9, 12-17). However, researchers are still debating from both sides (pro and con) of any potential nutritional advantages of consuming organic versus conventional fruits and vegetables and other plant products (9, 10, 12-18). As with all research, it is important to understand and question the methodology of any study and not draw broad conclusions from limited or incomparable data.
2. Organic meat may reduce the development of human antibiotic resistance and lessen air and water pollution (19).
3. In an ongoing cohort study, consumption of organic dairy products was associated with a lower risk of eczema during the first two years of life (20). The authors hypothesize “a high intake of omega-3 fatty acids and/or conjugated linoleic acids from organic dairy products by the child is protective against eczema (independent of atopy) and that also the mother’s intake of these fatty acids during pregnancy and lactation contributes to this protection” (20). One proposed mechanism to explain this association is the production of biologically active compounds and processes of intra-cellular signaling, since it is typical for molecules participating in processes of intra-cellular signaling to be present in very small amounts (21). Additional research is needed in this area (20, 21).
4. Organic agriculture offers numerous opportunities to reduce exposure to agricultural pesticides through the food and water supply (3), which may be detrimental to human health, particularly for high-risk groups such as pregnant women, infants, young children and farm worker households (22-27).
5. Organically cultivated foods can promote a more sustainable food system by reducing soil erosion and rehabilitating poor soils (7, 28). Many components of organic agriculture can be implemented within other sustainable farming systems (7).
6. Organic agriculture can integrate small- to medium-size farmers into high-value food chains/markets (7). Increasingly, larger farms and international producers have entered the organic marketplace; even so, the smallest organic farms have been able to maintain a stable share of the organic foods sector (3).
7. Organic agriculture has other documented heightened environmental services than conventional agriculture, including pollination services (29). Many agricultural food crops are dependent on pollination services provided by insects and other animals including birds. In contrast, synthetic pesticides used in agricultural production may negatively affect insects and other animals that are pollinators of food plants (28).
8. Organic agricultural systems offer multiple opportunities to help reduce greenhouse gas emissions and counteract global warming (7). Organic agriculture significantly lowers energy requirements for agricultural production systems compared to industrial agriculture (3, 7, 8). Long-term field experiments document that organic matter is higher in organically managed soil than in conventionally managed soil (7, 30). Humus (the well-decomposed part of soil organic matter) helps mitigate climate change by sequestering carbon and acting as a sink (e.g., by removing carbon dioxide from the atmosphere and fixing it in the soil) (7).
9. Biodiversity is enhanced in organic agricultural systems (3, 7, 28), which makes these farms more resilient to unpredictable weather patterns and pest outbreaks (7), as is predicted with climate change (31).
As shown above, the decision to choose organic products is influenced by many issues, including cost, health and environmental concerns. How to make sense of all the research and help consumers should be one of the roles of the RD and DTR. While there is still more work to be done, current research indicates there can be initial and long-term positive impacts on the health of individuals and the environment from the adoption of large-scale organic farming and food consumption. However, the potential of organic agriculture to improve the environmental performance of United States agriculture is having only a modest impact on the environment because the current organic adoption rate is low (3). Such that, the 2008 Food, Conservation and Energy Act (2008 Farm Bill) included increased “funding to help producers and handlers with organic certification costs, to enhance data collection on organic agriculture and to support Federal organic regulatory activities.”
The USDA’s Agricultural Marketing Service also administers several different grant programs, which have assisted a number of different local, organic initiatives across the US (3). “Public investment in organic agriculture facilitates wider access to organic food for consumers and helps farmers capture high-value markets and boost farm income, as well as conserve nonrenewable natural resources and protect US soil and water.” (3).
1. Organic Trade Association’s 2009 Organic Industry Survey. May 2009. Greenfield, MA: Organic Trade Association. Available at: www.ota.org/. Accessed on July 1, 2009.
2. National Organic Program (NOP). Organic Production and Handling Standards. United States Department of Agriculture (USDA), Agricultural Marketing Service. October 2002 (Updated April 2008). Available at: www.ams.usda.gov/nop. Accessed July 25, 2009.
3. Greene C, Dimitri C, Lin Biing-Hwan, McBride W, Oberholtzer L, Smith T. Emerging Issues in the US Organic Industry. Economic Information Bulletin Number 55. Washington DC: United States Department of Agriculture, Economic Research Service; June 2009; 28 pages.
4. Mills LS. From local chow to green machines: ADA members are turning foodservice into eco-friendly operations. ADA Times. January/February 2008:12-17.
5. Forbes CB, Harmon AH. Buying into community supported agriculture: strategies for overcoming income barriers. J Hunger Environ Nutr. 2007;2:65-80.
6. Smith TA, Lin B-H. Consumers willing to pay a price premium for organic produce. Amber Waves. Washington, DC: USDA, Economic Research Service. March 2009.
7. Niggli U, FlieBbach A, Hepperly P. Scialabba N. Low Greenhouse Gas Agriculture: Mitigation and Adaptation Potential of Sustainable Farming Systems. Rome, Italy: Food and Agriculture Organization of the United Nations (FAO); April 2009. Available at: ftp://ftp.fao.org/docrep/fao/010/ai781e/ai781e00.pdf. Accessed June 29, 2009.
8. Ziesemer J. Energy Use in Organic Food Systems. Natural Resources Management and Environment Department, Food and Agriculture Organization of the United Nations. Rome, Italy: FAO, August 2007. Available at: www.fao.org/docs/eims/upload/233069/energy-use-oa.pdf. Accessed July 3, 2009.
9. Lairon D. Nutritional quality and safety of organic food. A review. Agron Sustain Dev. 2009;DOI: 10.10151/agro/2009019
10. Dangour AD, Dodhia SK, Hayter A, Allen E, Lock K, Uauy R. Nutritional quality of organic foods: a systematic review. Am J Clin Nutr. 2009;DOI: 10.3945/ajcn.2009.28041
11. 2009 US Families’ Organic Attitudes & Beliefs Study. Executive Summary. A Joint Project of Organic Trade Association and KIWI Magazine. Conducted by RMI Research and Consulting, LLC. Greenfield, MA: Organic Trade Association. June 2009. Available at: www.ota.org/. Accessed July 1, 2009.
12. Strackle BA, Rufer C, Weibel FP, Bub A, Watzl B. Three-year comparison of the polyphenol content and antioxidant capacities in organically and conventionally produced apples (Malus domestica Bork. Cultivar ‘Golden Delicious’). J Agric. Food Chem. 2009;57:4598-4605.
13. Benbrook C. The impacts of yield on nutritional quality: lessons from organic farming. Hort Science. 2009;44:12-14.
14. Wang SY, Chen C-T, Sciarappa W, Wang CY, Camp MJ. Fruit quality, antioxidant capacity and flavonoid content of organically and conventionally grown blueberries. J Agric Food Chem. 2008;56: 5788-5794.
15. Dani C, Oliboni LS, Vanderlinde R, Bonatto D, Salvador M, Henriques JA. Phenolic content and antioxidant activities of white and purple grape juices manufactured with organically or conventionally produced grapes. Food Chem Toxicol. 2007;45:2574-80.
16. Mitchell AE, Hong Y-J, Koh E, Barrett DM, Bryant DE, Denison RF, Kaffka S. Ten year comparison of the influence of organic and conventional crop management on the content of flavonoids in tomatoes. J Agric Food Chem. 2007;55:6154-6159.
17. Olsson ME, Andersson CS, Oredsson S, Berglund RH, Gustavsson KE. Antioxidant levels and inhibition of cancer cell proliferation in vitro by extracts from organically and conventionally cultivated strawberries. J Agri Food Chem. 2006;54:1248-1255.
18. Magkos F, Arvanitia F, Zampelas A. Organic food: nutritious food or food for thought? A review of the evidence. Int J Food Sci Nutr. 2003;54:357-371.
19. American Medical Association (AMA). Report of the Council on Science and Public Health (CSAPH). CSAPH Report 8-A-09. Sustainable Food, Resolution 405, A-08.2008. Available at: www.ama-assn.org/ama1/pub/upload/mm/475/refcomd.pdf Accessed on June 20, 2009.
20. Kummeling I, Thijs C. Huber, M, van de Vijver LPL, Snijders BEP, Penders J, Stelma F, van Ree R, van den Brandt, PA, Dagnelie PC. Consumption of organic food and risk of atopic disease during the first 2 years of life in the Netherlands. Br J Nutr. 2008;99:598-605.
21. Rist L, Mueller A, Barthel C, Snijders B, Jansen M, Simoes-Wust AP, Huber M, Kummeling I, von Mandach U, Steinhart H, Thijs C. Influence of organic diet on the amount of conjugated linoleic acids in breast milk of lactating women in the Netherlands. Br J Nutr. 2007;97:735-743.
22. Huen K, Harley K, Brooks J, Hubbard A, Bradman A, Eskenazi B, Holland N. Developmental changes in PON1 enzyme activity in young children and effects on PON1 polymorphisms. Environ Health Perspect. 2009; DOI: 10.1289/ehp.0900870
23. Lu C, Barr DB, Pearson MA, Waller LA. Dietary intake and its contribution to longitudinal pesticide exposure in urban/suburban children. Environ Health Perspect. 2008;116:537-542.
24. Arcury T, Grzywacz, Barr D, Tapia J, Chen H, Quandt S. Pesticide urinary metabolites levels of children in Eastern North Carolina farmworker households. Environ Health Perspect. 2007;115:1254-1260.
25. Lu C, Toepkel K, Irish R, Fenske RA, Barr DB, Bravo R. Organic diets significantly lower children’s dietary exposure to organophosphorus pesticides. Environ Health Perspect. 2006;114:260-63.
26. Furlong CE, Holland N, Richer R, Bradman A, Ho A, Eskenazi B. PON1 status of farmworker mothers and children as a predictor of organophosphate sensitivity. Pharmacogenet Genomics. 2006;16:183-90.
27. Curl C, Fenske RA. Elgthun K. Organophosphorus pesticide exposure of urban and suburban preschool children with organic and conventional diets. Environ Health Perspect. 2003;111:377-382.
28. Harmon, AH, Gerald, BL. Position of the American Dietetic Association: Food and Nutrition Professionals Can Implement Practices to Conserve Natural Resources and Support Ecological Sustainability. J Am Diet Assoc. 2007;107:1033-1043.
29. Sandu HS, Wratten, SD, Cullen R, Case B. The future of farming: the value of ecosystem services in conventional and organic arable land: an experimental approach. Ecological Economics. 2008;64:835-848.
30. Marriott EE, Wander MM. Total and liable soil organic matter in organic and conventional farming systems. Soil Science Society of America Journal. 2006;70:950-959.
31. Worldwatch Institute. Questions and Answers about Global Warming and Abrupt Climate Change. Available at: www.worldwatch.org/node/3949. Accessed on July 26, 2009.
Written by Christine McCullum-Gomez, PhD, RD and Anne-Marie Scott, PhD, RD of the Hunger and Environmental Nutrition Dietetic Practice Group.