Organics: does the science validate it?

Consumers feel in their gut that organically produced foods are safer to eat and healthier for the environment by dint of fewer chemical residues and inputs. Todd Runestad investigates whether the state of the science has matched consumer expectations

Do organic products really offer proven human health and environmental benefits over conventional food products? Do organic farming methods have beneficial effects on the nutritional quality of food? Are agricultural chemical residues in food and the environment bad for consumers? And if the answer is yes to any of the above issues that lie at the heart of organic advocacy, can the results be quantified?

When the organic standards were first proposed in the US more than a decade ago, there was little scientific evidence to support an affirmative answer to any of these questions. And while anything short of God handing down engraved tablets pronouncing organics to be better than chemical-intensive foods will not likely get the USDA to publicly proclaim so much, a body of evidence is accumulating. Although still preliminary, the research is looking like it is validating many of the claims asserted by organic advocates.

"We haven't been able to shake the label, yet, that we're 'alternative,'" says Mark Davis, chief executive officer of The Organic Center, the US research advocacy group. "In reality, organic farming has been the traditional, historic way to grow. It's using chemicals that is alternative. But we will shake that label."

Despite organic foods comprising almost three per cent of the entire retail food market in the US, federal funding aimed specifically at organic growers makes up $3 million annually — less than one tenth of one per cent of current farm-bill spending. The farm bill is up for its five-year renewal in 2007, and organics advocates are poised to get this spending increased dramatically — in Europe, a four-year government-sponsored organics research initiative is budgeted at 100 million Euros.

The challenge for researchers is to demonstrate an advantage that is more than merely being free of undesirable chemicals that may or may not amount to anything significant. The accumulated research can be broken down into a handful of areas. These range from differences on the farm — from usage of chemicals and energy to soil quality and yield — to chemical exposure in consumers, to nutrient density of crops and foods.

Down on the farm
The great benefit of chemical-intensive agricultural practices has been a significant increase in crop yield per acre. Indeed, post-World War II America was heralded as being able to feed the world with its vast acreage of crops throughout the heartland.

So it came as a great surprise to read the results of a 22-year farming trial led by Cornell University, New York, researchers, published in 2005, finding that organic farming produces the same yields of corn and soybeans as conventional agricultural practices - but does so using 30 per cent less energy and water, inducing less soil erosion, and maintaining soil quality - and all with no pesticides. For the first four years, organic-corn yields were about two thirds that of conventional, but over time wind and water erosion degraded the soil on the conventional farm whereas the organic farm soil steadily improved in organic matter, moisture, microbial activity and other quality indicators. During a ten-year drought, from 1988 to 1998, the organic-bean yield was 22 per cent higher compared to conventional.1

Chemical load
The risks of cumulative pesticide load on the human body is not a well-studied field. Like GMOs that have followed, the primary beneficiary has gone to the chemical supplier and the farmer, whose job presumably becomes easier with fewer diseased crops to be concerned about. Clearly fewer pesticide residues means less risk for the consumer, but the question remains whether the amount of exposure is significant.2

Studies of chemical residues in plants show lower concentrations in organic foods. In a three-year Greek study comparing organic olive oil to conventional, levels of the pesticide fenthion for conventional olive oils were 0.1222, 0.145 and 0.1702mg/kg compared to 0.0215, 0.0099 and 0.0035 for organic. For the pesticide dimethoate, conventional was 0.0226, 0.0264 and 0.0271, and organic was 0.0098, 0.0038 and 0.0010mg/kg.3 Both of these chemicals are deemed 'moderately hazardous' by the World Health Organization. The estimate of an acceptable daily intake (ADI) for humans for dimethoate is 0.01mg/kg, based on the no-observed-adverse-effect level in humans of 0.2mg/kg body weight per day. For fenthion, the ADI is 0.02mg/kg.4

That there were still detectable levels of chemicals in organic foods demonstrates that, although synthetic chemical pesticides and chemical fertilizers are not applied to organic crops, they still face exposure from being blown by the wind from nonorganic fields.

Studies show that eating organic foods results in 'dramatic and immediate' reduced exposure to pesticides used on crops. In one study funded by the US Environmental Protection Agency, children ages three to 11 who ate organic foods for 15 days experienced a decrease to nondetectable levels of two organophosphate pesticides — until they switched back to a conventional diet.5

Are exposure levels significant? According to one study: yes. Urine samples of children eating either an organic or conventional diet were compared. With dimethyl metabolites, conventional eaters were deemed to have an 'uncertain risk' vs organic eaters' 'negligible risk.' 6

Even pesticides that have been long banned in the US, such as DDT, are still used in countries that export their foods into the US, meaning that although DDT is not used in the US, American consumers may still face exposure to it.

"If you're looking for chemical WMDs, they're in our food and we put them there," observes Alan Greene, MD, a professor at the Stanford University School of Medicine and leading organic advocate.

Nutrient density
A recent landmark study comparing the nutritional content of conventional fruits, vegetables and some crops grown in the US 50 years ago to those grown today found a drastically reduced nutrient content in today's food. One study comparing mineral depletion in foods between 1940 and 1991 found an average 47 per cent decline in iron content in 15 different kinds of meat and a 60 per cent decline in iron content of milk. Magnesium levels in meats fell 10 per cent and copper by 60 per cent.7

A more recent study comparing food composition data for 43 garden crops between 1950 and 1999 found a statistically significant decline in six nutrients — protein, calcium, iron, riboflavin, ascorbic acid and phosphorus. Specifically, the declines were: protein -6 per cent, calcium -16 per cent, phosphorus -9 per cent, iron -15 per cent, riboflavin -38 per cent, and vitamin C about -20 per cent. There were no statistically reliable median changes for ash, vitamin A, thiamin, niacin, carbohydrate or fat. The authors concluded that "there may be trade-offs between yield and nutrient content."8

At issue is whether the modern, chemically intensive agricultural practices are responsible, and whether organically produced foods can make up the difference.

The hypothesis is that high-yield crops grow bigger and faster, but do not take up nutrients from the soil at the same rates. The upshot is larger sizes of produce but with comparatively fewer nutrients per bite. This is commonly referred to as the 'dilution effect,' in which yield-enhancing methods like fertilisation and irrigation may decrease nutrient concentrations.9 This phenomenon may also be due to a higher water content in conventional crops, which causes nutrient dilution. Because organic foods tend to be smaller than their conventional counterparts, it is thought the attendant smaller cell size could translate to higher nutrient density.

In one assessment, USDA scientists assessed the lycopene content of 13 ketchup brands and found the average level in organic varieties to be about 55 per cent higher than the nonorganic varieties.10 A 2001 review of 41 studies comparing the nutritional value of organic and conventional produce found organic crops with an average 27 per cent higher levels of ascorbic acid, 21 per cent higher levels of iron, 29 per cent more magnesium, 14 per cent more phosphorus and lower levels of nitrate, and improved protein quality compared with conventionally grown crops.11

Organically raised plants that do not have chemical pesticides, herbicides and fungicides applied experience more stress because they must more or less fend for themselves. The result is they produce more endogenous antioxidants like phenolics to combat the stress factors. Hence, the self-made addition of more phytonutrients translates to a more nutritious food for the end user.12,13

This phenomenon also holds true for livestock fed organic diets — animal studies show better growth and reproduction in animals fed organically grown feed compared with those fed conventionally grown feed.14

In a three-year comparison of nutrient levels in organic vs conventional, researchers assessed total phenolics per cent soluble solids; ascorbic acid; and the flavonoid aglycones quercetin, kaempferol and luteolin in two varieties of tomato (Ropreco and Burbank) and two varieties of bell peppers (California Wonder and Excalibur). Significantly higher levels of per cent soluble solids (17 per cent), quercetin (30 per cent), kaempferol (17 per cent), and ascorbic acid (26 per cent) were found in Burbank tomatoes, whereas only levels of per cent soluble solids (10 per cent) and kaempferol (20 per cent) were significantly higher in organic Ropreco tomatoes. Burbank tomatoes generally had higher levels of quercetin, kaempferol, total phenolics and ascorbic acid as compared to Ropreco tomatoes. Bell peppers were influenced less by environment and did not display cropping system differences.15 This latter point suggests more research is needed to discern which specific food crops can benefit from organic growing conditions vis-á-vis nutrient content levels.

New research out of Belgium has centred upon the differences in bioactive concentrations within hops, which is a large focus of several companies pursuing these bioactives for anti-inflammatory, sedative/anxiolytic, and phyto-estrogenic applications. Three key points came out of this study. For one, like the tomato study mentioned above, this study also found that organically grown hops had higher concentrations of bioactives such as chalcones. Secondly, concentrations of the key compounds depended very much on climatological conditions showing, in general, the highest levels in poorest weather conditions. Thirdly, the first gold hop varietal showed the clearest results, with the admiral and wye challenger varietals having less clear distinctions between growing regimes. Again, this demonstrates that plants grown in stressful conditions tend to be more nutritious for human consumption.16

In contradistinction, recent German research found no difference in wheat grains.17 Similar results from Finnish researchers found no difference in blackcurrant bioactive profiles.18 A conservative assessment by Greek researchers in 2003 noted trends toward higher ascorbic-acid levels in leafy greens and potatoes, higher-quality protein levels in some vegetables and cereal crops, and better animal health — but findings have not yet been identified in humans.19 A recent British study found that organic milk contains 68 per cent more short-chain omega-3 fatty acids than conventional milk due to the higher proportion of clover forage in the diets of organic cows.20 However, the finding was disputed by the UK's Food Standards Agency because those levels were not significant enough to translate to clear human benefit. Again, the clear conclusion is the need for additional research in this area.

One provocative notion, with only a rat study to show thus far, is the idea that, with obesity, consumers eating organic foods will eat less foods, but those foods are more nutrient-dense, and not merely hollow calories.21

The organic future
Annual growth rates of 20 per cent testifies to consumers buying into the idea that they are doing something good - for the environment and for themselves — when they buy organic foods. The scientific record is far from complete, but at this point it would appear that research and marketing are headed in the same, positive direction. While comparisons of health outcomes in populations that habitually consume organic or conventional foods are inherently flawed by the large number of confounding factors that might contribute to differences reported, it is clear that organic agriculture is environmentally sound and more sustainable than mainstream agriculture, that fewer synthetic chemicals are used and consumed, and that organic foods tend to have higher nutrient levels, which may well be one of the answers to modern debilitating diseases that are found in modern societies eating modern diets. With organic foods, it seems, everything old is new again.

Organics is profitable — if you can source it

If the organics market is to sustain its double-digit growth rates, manufacturers need to start thinking about issues as far reaching as squeezes on prices and availability, spot purchases, China, and global warming.

The changing global marketplace is affecting supply, and systems need to be put in place now to ensure a consistent supply of quality organic ingredients in the coming years.

"The factors that drive supply challenges include market growth, the three-year transition barrier, availability of imports and an increase in the number of processed foods," says Mary Mulry, president of Foodwise consultancy and member of the board of directors of the Organic Trade Association (OTA). "The market has reached a critical mass. Everyone's focused on it because it's the only thing that's growing."

Everyone agrees demand is affecting prices. What is surprising are the many variables other than consumer demand. Organic feed prices are now equivalent to human food prices — an unprecedented occurrence. Global warming alone has many issues that are altering the organic landscape, including food mileage — an issue of concern to global suppliers. In the US, concerns about global warming have led to a surge in interest in ethanol-based gasoline for automobiles. This takes agricultural acreage off the table for organics.

"The ethanol issue is serious," says George Kalogridis, an organic veteran as farmer and broker who sits on the OTA's ingredients-supplier forum. "Organic grain prices will go up because the price is the same for organic grain as it is for ethanol. You need to be aware of it and realize there's nothing you can do about it."

China, too, has a number of factors surrounding it. Among them are the quality and trustworthiness of organic ingredients.

"The image of organic food products coming from China to the US is not good," says Udo Censkowsky, cofounder and managing director of Organic Services, a consulting firm based in Germany. "There are problems in China, but the government is investing a lot to improve it and develop better certification resources. But buying on the spot market in China is quite risky. I wouldn't recommend it."

Censkowsky says that China will remain a strong player to buy organics for the next five years. But the country's domestic market is also seeing solid growth, which should open opportunities in the short-term to export products back into China. Long-term, however, he sees the domestic Chinese market overwhelming its domestic supply.

The organic market differs radically from conventional foods in that 70 per cent of organic is grown under contract, compared to only about 20 per cent of conventional foods, says Kalogridis. "This means if you're trying to buy on spot, it won't be there. You need to contract for your ingredients. When you have sourcing problems, you get to know who the good brokers are."

Another strategy for securing a supply is simply to "diversify sourcing origins," suggests Censkowsky.

Manufacturers might also think about helping farmers to successfully make it through the three-year transitional period by paying more for transitional crops and use those in their 'natural' product line, adds Kalogridis.


What it means to be organic

Organic agriculture is an agricultural production management system that promotes biodiversity, biological cycles and soil-biological activity. The primary goal is to optimise the health and productivity of interdependent communities of soil life, plants, animals and people. Foods certified as organic must adhere to a litany of regulations. The more significant ones include:

  • The use of synthetic pesticides and herbicides is prohibited.
  • Genetically modified organisms (GMOs) are prohibited.
  • Irradiation of foods is prohibited.
  • Use of processed sewage sludge on crops is prohibited.
  • Livestock must be given access to pasture.
  • Livestock cannot be given growth hormones or antibiotics.
  • Livestock must eat organically grown. feed, with no animal byproducts.
  • Land must be free of chemical applications for at least three years.
  • Growers must have detailed farm-systems plans.
  • Products sold as organic must be certified by an independent, third-party certifier.
  • In the US, the National Organic Standards Board, a citizen advisory board, is mandated to make recommendations to the USDA about organic regulations.

There are four categories end products marketed in the US. Go to for more information.

    The categories are:
  • 100 per cent organic
  • Organic: 95 per cent of ingredients must be certified organic
  • Made with organic ingredients: 70 per cent of ingredients are certified organic
  • Less than 70 per cent organic: Organic ingredients can be listed on the side panel only

Select Suppliers

ADM: Agribiz giant offers organic corn, soy, sunflower oil, rye, xanthan gum and vitamin E.

American Health & Nutrition: Worldwide supplier of certified-organic grains, beans, seeds, soy-protein powders, and other commodities.

Bioriginal: Canadian global provider of innovative essential fatty acid (EFA) solutions offers organic flax.

Briess Malt & Ingredients: Makes a standard line of certified-organic malts and ingredients. In addition, any Briess malt or ingredient can be made as a certified-organic product.

California Natural Products: Offers rice oligodextrins, syrups, flour, protein concentrates and more.

Ciranda: TapiOK brand organic dextrose from tapioca is just like dextrose, though this is organic and nonallergenic, with optimum flowability, superior compressability and exceptional solubility.

Devansoy: Specialist in all-natural and organic processing of soy ingredients.

Kerry: Recent organic expansion now offers organics in flavours, cereal, cheese and dairy, lipids, proteins, seasonings, and sweet ingredients.

Mastertaste: Flavour house division of Kerry Food Ingredients has a line of organic essential oils and extracts, organic flavour systems and ingredients.

Nexcel Natural Ingredients: A division of Spectrum Foods, offers a full line of organic edible oils including soybean oil, canola oil, high-oleic sunflower oil, safflower oil, palm shortening and soy/palm shortening blends.

Organics Unlimited: California-based distributor of organic tropical fruits from Mexico and South America.

PL Thomas: Organic ingredients are Ecoguar organic guar gum; Guar galactomannan from the endosperm of legume seed; a locust bean gum; and Nutricran-Organic, a spray-dried cranberry concentrate powder standardised to a minimum of 90 per cent cranberry fruit solids.

QAI: Independent, third-party certifier of organic food systems. Its verification effort documents the authenticity of organic farming and various subsequent levels of handling.

Savoury Systems International: Flavour house with organic-compliant products as well as Savorganic, a line of certified organic yeast extracts in both powder and liquid form.

SK Food International: Supplies a full line of identity-preserved ingredients, including certified organic and conventional non-GMO dry beans, grains, seeds, soybeans, brans/germs, cocoa, flours, oils and vinegars, meals, sweeteners, rice products, and fibres.

SunOpta Grains and Foods Group: Organic and natural soy, dairy, corn, sunflower and whole grains, fibres, stabilised brans (oat, wheat, corn), wheat germ, specialty starches, cellulose gel, konjac, dry sweeteners (honey, molasses), fruits, and vegetables.

Tradin Organic: Dutch-based company specialising in the international sourcing and supply of organic ingredients for the world food and bakery industry, from seed oils, flours, and grains to fruits and vegetables.

Treatt: Supplier to the flavour and fragrance industries, recently strengthened its position in organics by partnering with Earthoil, a fair-trade and organic essential and pressed seed-oil supplier.

Virginia Dare: Flavour house expertise in the sourcing and regulatory requirements for natural, organic and organic-compliant flavour materials.

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2. Magkos F, et al. 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.
3. Tsatsakis AM, et al. Three-year study of fenthion and dimethoate pesticides in olive oil from organic and conventional cultivation. Food Addit Contam 2003 Jun;20(6):553-9.
5. Chensheng Lu, et al. Organic diets significantly lower children's dietary exposure to organophosphorus pesticides. Environ Health Perspec 2006 Feb;114(2).
6. Curl CL, et al. Organophosphorus pesticide exposure of urban and suburban preschool children with organic and conventional diets. Environ Health Perspect 2003 Mar;111(3):377-82.
7. Thomas D. A study on the mineral depletion of the foods available to us as a nation over the period 1940 to 1991. Nutr Health 2003;17(2):85-115.
8. Davis DR, et al. Changes in USDA food composition data for 43 garden crops, 1950 to 1999. J Am Coll Nutr 2004 Dec;23(6):669-82.
9. Worthington V. Effect of agricultural methods on nutritional quality: a comparison of organic with conventional crops. Altern Ther Health Med 1998 Jan;4(1):58-69.
10. Ishida BK, Chapman MHA. Comparison of carotenoid content and total antioxidant activity in catsup from several commercial sources in the United States. J Agric Food Chem 2004; 52(26):8017-20.
11. Worthington V. Nutritional quality of organic versus conventional fruits, vegetables and grains. J Altern Complement Med 2001 Apr;7(2):161-73.
12. Johnson KS, Felton GW. Plant phenolics as dietary antioxidants for herbivorous insects: a test with genetically modified tobacco. J Chem Ecol 2001 Dec;27(12):2579-97.
13. Bi JL, et al. Do plant phenolics confer resistance to specialist and generalist insect herbivores? J Agric Food Chem 1997;45:4500-4.
14. Worthington V. Effect of agricultural methods on nutritional quality: a comparison of organic with conventional crops. Altern Ther Health Med 1998 Jan;4(1):58-69.
15. Chassy AW, et al. Three-year comparison of the content of antioxidant microconstituents and several quality characteristics in organic and conventionally managed tomatoes and bell peppers. J Agric Food Chem 2006 Oct 18;54(21):8244-52.
16. De Keukeleire J, et al. Relevance of organic farming and effect of climatological conditions on the formation of alpha-acids, beta-acids, desmethylxanthohumol, and xanthohumol in hop (Humulus lupulus L.) J Agric Food Chem 2007;55:61-6.
17. Gelinas P, McKinnon CM. Effect of wheat variety, farming site, and bread-baking on total phenolics. Int J Food Sci Tech 2006;41(3):329-32.
18. Mikkonen TP, et al. Flavonol content varies among black currant cultivars. J Agric Food Chem 2001 Jul;49(7):3274-7.
19. Magkos F, et al. Organic food: nutritious food or food for thought? A review of the evidence. Int J Food Sci Nutr 2003 Sep;54(5):357-71.
20. Dewhurst RJ, et al. Comparison of grass and legume silages for milk production. Production responses with different levels of concentrate. J Dairy Sci 2003;86:2598-2611.

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