September 2017 Issue
Organics: Organic Dairy Myths and Facts
By Carrie Dennett, MPH, RDN, CD
Today's Dietitian
Vol. 19, No. 9, P. 16
Help patients make an educated choice for better health and the environment.
Organic milk has been in the news frequently this year, with reports of farmers dumping excess organic milk and investigations questioning whether some organic milk really is organic. Overall, more consumers are choosing organic foods at least occasionally, and more mass-market retailers are selling them.
As a result, organic milk is no longer a niche product. Consumer demand for organic milk has been expanding, especially in the United States.1 According to IRI scanned retail sales volume data provided by the National Dairy Council (NDC), organic milk and dairy now represent an estimated 15% of organic food sales and 4.6% of total dairy sales. But what's driving this growth—and has the bubble burst?
Growing Trend
While fluid milk always has been the biggest driver of the organic dairy market, currently accounting for 92% of all organic dairy sales, NDC data show that organic yogurt represents 7% of organic dairy sales and 4% of total yogurt sales. And while organic cheese has carved out only 1% of organic dairy sales and 0.5% of all dairy sales, its sales more than doubled between 2012 and 2016.
In April, the media began reporting on an oversupply of organic milk on the market, with headlines such as "Even the hipster organic milk craze isn't enough to end glut."2 Although these media reports cite overproduction as the cause, USDA data for monthly total organic fluid milk sales show that demand, while still increasing over time, has been slowing since 2014,3 but sales of nonorganic fluid milk are down, too.
Organic dairy saw growth in 2012–2014, but nearly flattened the following year. After a smaller rate of growth in 2015–2016, the market was down slightly this year as of the end of June. "Once farms convert to organic production, it will take some time for enough to convert back to conventional production in order to scale production growth to slower-growing demand," says Erin Coffield, RDN, LDN, of the National Dairy Council.
While reasons for not purchasing organic foods vary, concerns about antibiotics, growth hormones, and pesticides often top the list of reasons to purchase them, as do broader concerns about animal welfare and the environment.4 Many consumers believe organic foods are more healthful and nutritious than conventional foods,5 and research shows this drives many organic food purchases.6,7 Coffield cites the Hartman Group Organic & Natural 2016 report, which says consumers purchase organic food and beverages based on the following desires and perceptions, in order of importance:
• avoidance of farm-level pesticides and chemicals;
• organic foods are "safer for me";
• avoidance of products that rely on growth hormones;
• avoidance of products that rely on antibiotics; and
• avoidance of genetically modified products.
Defining Organic Dairy
The three aspects of USDA organic regulations for dairy that most consumers are interested in are related to pesticides, antibiotics, and growth hormones,4 although beliefs about the differences between organic and conventional dairy are based on both myths and facts.
It's true that all feed provided to organic dairy cows—including fresh pasture, hay, grain, and other agricultural products—must be free from GMOs and grown without the use of synthetic fertilizers, pesticides, and herbicides. In fact, part of the organic certification process includes documenting that no prohibited substances were applied to grazing land for the previous three years.8 It's also true that the use of recombinant bovine growth hormone (rBGH) isn't allowed in organic dairy production. However, more stores are refusing to carry milk from rBGH-treated cows, so its use in conventional herds in the United States, while allowed, has been declining for years.9
Where mythology starts to emerge is with antibiotic use. While the use of subtherapeutic doses of antibiotics isn't allowed in organic livestock, the practice isn't common in conventional dairy herds compared with beef herds. Antibiotics are allowed for treating bacterial infections in both organic and conventional dairy herds.8 Consumers may think that by opting for organic milk, they're avoiding ingesting antibiotic residues, but the truth is that antibiotic residues aren't permitted in any milk. If a conventional cow is treated with antibiotics, her milk can't be sold until the number of days has passed on the drug label, as mandated by the FDA. If any milk tests positive for antibiotics, no milk from that tank can be sold. Of the nearly 38,000 dairy samples the FDA tested in 2014, none tested positive for traces of antibiotics.10 The slight difference between organic and conventional dairy farms is that if an organic cow needs antibiotics, she's permanently removed from the milking herd.8
Another myth about organic dairy is that organic cows are 100% grass-fed. Under USDA Certified Organic regulations, dairy cows must have free access to certified organic pasture for the entire grazing season. This typically runs from spring through the first frost—at least 120 days per year—but will vary based on geography and climate. During the grazing season, at least 30% of the cow's forage (grass, legumes, and silage) needs must come from grazing on certified organic pasture. Organic grain, corn, and soybeans also are allowed. During the nongrazing season, dairy cows must have free access to the outdoors, weather permitting.8
Health and Environmental Effects
Consumers are willing to pay more for milk with higher levels of omega-3 polyunsaturated fatty acids,7 but this is difficult to achieve in ruminant animals such as cattle. Most of the polyunsaturated fatty acids in the cow's feed, whether that be grain or grass, are converted to saturated fatty acids in the rumen, the first chamber in the cow's alimentary canal.11,12 About 70% of the fats in milk are saturated, 25% are monounsaturated, and 2.3% are polyunsaturated.13 However, the fatty acid composition of milk depends on several factors, including genetics, how and where the cow was raised, where she is in her lactation cycle (the period between one calving and the next), diet, and season (spring vs summer or grazing vs nongrazing).14
When dairy cows—whether organic or conventional—eat a grass diet, they produce milk that's higher in omega-3s.15 Alpha-linolenic acid (ALA) is the predominant omega-3 fatty acid in milk. Although ALA levels are consistently higher in grass-fed milk and organic milk, the amounts of the long-chain omega-3s EPA and DHA are present in much smaller amounts, even in grass-fed milk. These forms are most important to human health and chronic disease prevention; human conversion of ALA to EPA or DHA is limited.14,16,17
In 2016, a meta-analysis of 170 published studies compared the fatty acid compositions of organic and conventional milk.18 The results revealed no significant differences in total saturated fatty acid and monounsaturated fatty acid concentrations, but found that organic milk contained 7% more total polyunsaturated fatty acids and 56% more omega-3s than conventional. Concentrations of ALA were 69% higher, levels of EPA and DHA were 57% higher, and levels of conjugated linoleic acid were 41% higher.18 However, levels of ALA are still far lower than what's found in walnuts or flaxseeds, and levels of EPA and DHA are far lower than what's present in fish and seafood. Limited research suggests that conjugated linoleic acid has anticarcinogenic and antiatherogenic effects, but, even if this is true, the amounts needed would be significantly higher than what's present in milk fat.14,16
Despite the difficulty of shifting the fatty acid composition of milk, research does show there's a difference in fatty acid composition between organic and conventional milk. The differences are great enough that fatty acid analysis is used to authenticate the origins of bulk milk.19,20 In fact, a large organic dairy producer, Aurora Organic Dairy, came under fire in May after an investigative report by The Washington Post claimed that only a small percentage of the cows was on pasture and that an independent lab analysis found that the fatty acid profile of Aurora milk was similar to conventional milk. Aurora supplies the "private label" (or store-brand) milk to Costco, Walmart, and other major retailers.21
According to the Organic Center, a nonprofit organization based in Washington, D.C., organic dairy farms have less of a negative impact on land, air, and water quality than conventional dairy farms, giving them a reduced "environmental footprint." This is partly because organic dairies don't use synthetic pesticides and fertilizers that can leach into water and soil, but also because they use significantly less "prime" land. When organic dairies use Jersey cows instead of Holsteins, for example, they produce significantly less manure, which leads to less methane—a gas that may contribute to global warming—and less nutrient runoff of nitrogen, phosphorous, and potassium, for example, which helps protect water quality.22
Bottom Line
Even if there are nutritional differences between organic and conventional dairy, there's no evidence that the differences are clinically meaningful. Both organic and conventional dairy farmers care for their animals, and both types of farms may be small family farms or large mega-farms. Use of sustainable farming practices has benefits for the environment and the future of farmland health, but the avoidance of pesticide use in organic dairy production is just one part of that. Dietitians can help patients separate myth from fact so they can make the best, most educated decisions for themselves and their families.
— Carrie Dennett, MPH, RDN, CD, is the nutrition columnist for The Seattle Times and speaks frequently on nutrition-related topics. She also provides nutrition counseling via the Menu for Change program in Seattle.
References
1. U.S. organic sales post new record of $43.3 billion in 2015. Organic Trade Association website. https://www.ota.com/news/press-releases/19031. Published May 19, 2016.
2. Durisin M. Even the hipster organic milk craze isn't enough to end glut. Bloomberg Markets website. https://www.bloomberg.com/news/articles/2017-04-25/organic-premium-slips-as-too-many-cows-create-same-old-milk-glut. Updated April 26, 2017.
3. US Department of Agriculture. Organic Dairy Market News: information gathered June 19-30, 2017. https://www.ams.usda.gov/mnreports/dybdairyorganic.pdf
4. Kiesel K, Villas-Boas SB. Got organic milk? Consumer valuations of organic labels after the implementation of the USDA organic seal. J Agric Food Ind Org. 2007;5:1-38
5. Dangour AD, Lock K, Hayter A, Aikenhead A, Allen E, Uauy R. Nutrition-related health effects of organic foods: a systematic review. Am J Clin Nutr. 2010;92(1):203-210.
6. Over half of US consumers think organic labeling is an excuse to charge more. Mintel website. http://www.mintel.com/press-centre/food-and-drink/over-half-of-us-consumers-think-organic-labeling-is-an-excuse-to-charge-more. Published May 13, 2015.
7. Matthews KH, Johnson RJ; US Department of Agriculture, Economic Research Service. Alternative beef production systems: issues and implications. https://www.ers.usda.gov/webdocs/publications/37473/36491_ldpm-218-01.pdf?v=41368. Published April 2013.
8. US Department of Agriculture, National Organic Program. Organic livestock requirements. https://www.ams.usda.gov/sites/default/files/media/Organic%20Livestock%20
Requirements.pdf. Published July 2013.
9. Report on the Food and Drug Administration's review of the safety of recombinant bovine somatotropin: IGF-I. US Food and Drug Administration website. http://www.fda.gov/AnimalVeterinary/SafetyHealth/ProductSafetyInformation/
ucm130321.htm#IGF-I. Updated July 28, 2014.
10. US Food and Drug Administration, Center for Veterinary Medicine. Milk drug residue sampling survey. https://www.fda.gov/downloads/AnimalVeterinry/GuidanceComplianceEnforcement/
ComplianceEnforcement/UCM435759.pdf. Published March 2015.
11. Lourenço M, Ramos-Morales E, Wallace RJ. The role of microbes in rumen lipolysis and biohydrogenation and their manipulation. Animal. 2010;4(7):1008-1023.
12. Lock AL, Bauman DE. Modifying milk fat composition of dairy cows to enhance fatty acids beneficial to human health. Lipids. 2004;39(12):1197-1206.
13. Bjørnshave A, Hermansen K. Effects of dairy protein and fat on the metabolic syndrome and type 2 diabetes. Rev Diabet Stud. 2014;11(2):153-166.
14. Daley CA, Abbott A, Doyle PS, Nader GA, Larson S. A review of fatty acid profiles and antioxidant content in grass-fed and grain-fed beef. Nutr J. 2010;9:10-21.
15. Clancy K; Union of Concerned Scientists. Greener pastures: how grass-fed beef and milk contribute to healthy eating. http://www.ucsusa.org/sites/default/files/legacy/assets/documents/food_and_agriculture/
greener-pastures.pdf. Published March 2006.
16. O'Donnell AM, Spatny KP, Vicini JL, Bauman DE. Survey of the fatty acid composition of retail milk differing in label claims based on production management practices. J Dairy Sci. 2010;93(5):1918-1925.
17. Fleming JA, Kris-Etherton PM. The evidence for a-linolenic acid and cardiovascular disease benefits: comparisons with eicosapentaenoic acid and docosahexaenoic acid. Adv Nutr. 2014;5(6):863S-876S.
18. Średnicka-Tober D, Barański M, Seal CJ, et al. Higher PUFA and n-3 PUFA, conjugated linoleic acid, α-tocopherol and iron, but lower iodine and selenium concentrations in organic milk: a systematic literature review and meta- and redundancy analyses. Br J Nutr. 2016;115(6):1043-1060.
19. Molkentin J. Authentication of organic milk using delta13C and the alpha-linolenic acid content of milk fat. J Agric Food Chem. 2009;57(3):785-790.
20. Coppa M, Chassaing C, Ferlay A, et al. Potential of milk fatty acid composition to predict diet composition and authenticate feeding systems and altitude origin of European bulk milk. J Dairy Sci. 2015;98(3):1539-1551.
21. Whoriskey P. Why your "organic" milk may not be organic. The Washington Post. May 1, 2017. https://www.washingtonpost.com/business/economy/why-your-organic-milk-may-not-be-organic/2017/05/01/708ce5bc-ed76-11e6-9662-6eedf1627882_story.html
22. Benbrook C, Carman C, Clark EA, et al; The Organic Center. A dairy farm's footprint: evaluating the impacts of conventional and organic farming systems. https://organic-center.org/reportfiles/COFEFFinal_Nov_2.pdf. Published November 2010.