Major study documents benefits of organic farming
The largest study of its kind has found that organic foods and crops have a suite of advantages over their conventional counterparts, including more antioxidants and fewer, less frequent pesticide residues.
The study looked at an unprecedented 343 peer-reviewed publications comparing the nutritional quality and safety of organic and conventional plant-based foods, including fruits, vegetables and grains. The study team applied sophisticated meta-analysis techniques to quantify differences between organic and non-organic foods.
Quality of studies improves
“Science marches on,” said Charles Benbrook, a Washington State University researcher and the lone American co-author of the paper published in the British Journal of Nutrition. “Our team learned valuable lessons from earlier reviews on this topic, and we benefited from the team’s remarkable breadth of scientific skills and experience.”
Most of the publications covered in the study looked at crops grown in the same area on similarsoils. This approach reduces other possible sources of variation in nutritional and safety parameters.
The research team found the quality and reliability of comparison studies has greatly improved in recent years, leading to the discovery of significant nutritional and food safety differences not detected in earlier studies. For example, the new study incorporates the results of a research project led by WSU’s John Reganold that compared the nutritional and sensory qualities of organic and conventional strawberries grown in California.
Responding to the new paper’s results, Reganold said, “This is an impressive study, and its major nutritional findings are similar to those reported in our 2010 strawberry paper.”
Organic plants produce more antioxidants
The British Journal of Nutrition study was led by scientists at Newcastle University in theUnited Kingdom, with Benbrook helping design the study, write the paper and review the scientific literature, particularly on studies in North and South America.
In general, the team found that organic crops have several nutritional benefits that stem from the way the crops are produced. A plant on a conventionally managed field will typically have access to high levels of synthetic nitrogen and will marshal the extra resources into producing sugars and starches. As a result, the harvested portion of the plant will often contain lower concentrations of other nutrients, including health-promoting antioxidants.
Without the synthetic chemical pesticides applied on conventional crops, organic plants tend to produce more phenols and polyphenols to defend against pest attacks and related injuries. In people, phenols and polyphenols can help prevent diseases triggered or promoted by oxidative damage, like coronary heart disease, stroke and certain cancers.
Overall, organic crops had 18 to 69 percent higher concentrations of antioxidant compounds. The team concludes that consumers who switch to organic fruit, vegetables and cereals would get 20 to 40 percent more antioxidants. That’s the equivalent of about two extra portions of fruit and vegetables a day, with no increase in caloric intake.
10 to 100 times fewer pesticide residues
The researchers also found pesticide residues were three to four times more likely in conventional foods than organic ones, as organic farmers are not allowed to apply toxic, synthetic pesticides. While crops harvested from organically managed fields sometimes contain pesticide residues, the levels are usually 10-fold to 100-fold lower in organic food, compared to the corresponding, conventionally grown food.
“This study is telling a powerful story of how organic plant-based foods are nutritionally superior and deliver bona fide health benefits,” said Benbrook.
In a surprising finding, the team concluded that conventional crops had roughly twice as much cadmium, a toxic heavy metal contaminant, as organic crops. The leading explanation is that certain fertilizers approved for use only on conventional farms somehow make cadmium more available to plant roots. A doubling of cadmium from food could push some individuals over safe daily intake levels.
Team surveys more and better studies
More than half the studies in the Newcastle analysis were not available to the research team that carried out a 2009 study commissioned by the UK Food Standards Agency. Another review published by a Stanford University team in 2011 failed to identify any significant clinical health benefits from consumption of organic food, but incorporated fewer than half the number of comparisons for most health-promoting nutrients.
“We benefited from a much larger and higher quality set of studies than our colleagues who carried out earlier reviews,” said Carlo Leifert, a Newcastle University professor and the project leader.
The Newcastle study cost about $429,000 and was funded by the European Framework Programme 6, which is a research program of the European Union, and the Sheepdrove Trust, a private charity that supports research on sustainability, diversity and organic farming.
– Eric Sorensen
Quinoa: Seeds of hope for Rwandan researcher
A crop being test-grown at Washington State University’s Organic Farm is skyrocketing in popularity in North America. Even so, less than a year ago, a graduate student growing it at WSU had never seen or tasted it.
Then again, he’d never felt the cold tingle of snowflakes landing on his skin either.
Cedric Habiyaremye came to campus from Rwanda last August. Majoring in crop sciences, he’s become so hooked on the flavor and versatility of quinoa (pronounced KEEN-wah) that he’s cultivating it for his graduate research work.
He compares his experiment with quinoa to his watching in wonder one December night as snowfall quilted Pullman and coated the trees outside his campus apartment. Until then, he’d only seen the white stuff in movies.
“I stood outdoors in a tank top and shorts, looking up at the sky with my arms spread wide,” recalled Habiyaremye. “I thought, this snow is really amazing!”
Amazing, too, is how he describes quinoa seeds produced by the goosefoot plant, now growing in neat lines of green in a field at WSU’s Organic Farm. As the plants mature into stalks covered with knotty blossoms, they’ll produce small, flat, circular-shaped seeds that, after being processed and cooked, taste like a mild, earthy brown rice.
“For such a tiny seed, it has such big possibilities,” he said, arms outstretched like the first time he saw snow. “I am passionate about quinoa!”
That vibrant exclamation from a student for whom English is a fourth language – preceded by French, Swahili and Kinyarwanda – speaks volumes about Habiyaremye’s enthusiasm for his research. And, also, his desire to bring seeds of change to his country.
Testing to meet demand
Indigenous to the Andean highlands, quinoa is eaten like a grain but is actually a protein-packed seed related to spinach and beets. Though Peru and Bolivia are the world’s main suppliers, other countries, including the United States and Canada, are producing quinoa in small quantities as farmers try to figure out which varieties grow best and where.
Domestically, small-scale farmers have been growing quinoa in Colorado since the 1980s. But as the crop becomes a bigger part of the American diet, its cultivation is being tested at sites throughout the Pacific Northwest. WSU plant breeder Kevin Murphy oversees those sites; Habiyaremye’s carefully tended plot at the organic farm is among them.
“Which quinoa varieties to plant, what to intercrop them with, what kinds of soils work best – these are questions we’re trying to answer before farmers start trying to grow it in the U.S.,” said Murphy, who is also Habiyaremye’s advisor.
Heart full of quinoa
Standing alongside a swath of quinoa plants that he intercropped with potatoes, Habiyaremye talked about the foodstuff he tasted for the first time at the WSU-hosted International Quinoa Research Symposium. He remembers wondering how such a humble seed could provide such a nutritional and flavorful base for salads, soups, porridge and cereals.
“Cooked like grain, quinoa reminded me of cooked sorghum (an ancient staple grain in Africa and India) from my home country – only better. And knowing how nutritious it is, I became determined to learn everything I can about growing it,” he said. “I haven’t known quinoa for long, but I do know that it’s very special.”
Fueled by the past
Twenty years ago in Rwanda, when Habiyaremye was 7, ethnic genocide left close to a million people brutally slaughtered in 100 days. Since then, tourists have returned to the small east African country and the economy continues to rebound. Even so, 30 percent of the population remains malnourished, according to the United Nations Food and Agriculture Organization.
“Recalling how hunger was traumatic in my childhood, I decided that as a personal mission, I would try to find a solution so that children and families in Rwanda will not be held down by lack of nutritious food,” said Habiyaremye.
The solution, he believes, lies in quinoa – whose oddly pronounced name he heard for the first time from WSU crop sciences professor Kim Kidwell, whom he met in Rwanda when she led a two-week student practicum in 2012.
“‘KEEN-what?’ I asked her,” recalled Habiyaremye. “‘KEEN-what?’”
After the trip, Kidwell recruited him to WSU to study this promising agricultural novelty. Once armed with a master’s degree in 2016, he plans to return to Rwanda, grow the crop and introduce it to others.
In a country where more than half the people are subsistence farmers, he envisions a new shade of green amid the small family plots of sweet potatoes, cassava and maize. Quinoa’s seeds, leaves and flowers are all edible, he explained, offering high doses of essential amino acids, vitamins and minerals.
“Because it is so nutritious and well suited for small-scale and subsistence farming, I think it has great potential to contribute to my country’s food security,” he said.
Suited for other lands
How will a crop from the cloud-shrouded ridges of the Andes fare in a land of eucalyptus trees two degrees south of the equator?
That’s another remarkable thing about quinoa – it takes root in a variety of environments, said Murphy.
“It’s a diverse crop that appears to thrive in a variety of climates and altitudes,” Murphy said. “With Cedric’s determination, if anyone can get it to grow there, it’s him.”
Meanwhile, as Habiyaremye’s quinoa plants reach toward a hot July sun from their plots in Pullman, he remains hopeful, “my hope is that one day it becomes widely grown in Rwanda.”
– Linda Weiford
Washington organic ag by the numbers
When it comes to organic farm gate value (the total value of products when they leave the farm), Washington ranks #2 in the United States at $291 million – California is #1 and Oregon is #3. More than 50 percent of Washington’s organic farm gate sales come from tree fruit. Eastern Washington has the highest number of organic farms in the state. The graphic shows the counties with most organic farms east and west of the Cascades. Find more organic ag by numbers at http://csanr.wsu.edu/trends-in-washington-agriculture/organic-statistics.
– Sylvia Kantor
Everyone can can: WSU offers online food preservation courses
Juicy ripe peaches, snapping fresh green beans, sweet raspberry jam, and crunchy dill pickles – nothing tastes better than home-preserved foods. In addition, a well-stocked pantry is a big step towards ensuring your family always has plenty of healthy food available.
Just in time for canning season, WSU Extension is offering a new food preservation program called Preserve the Taste of Summer.
The series of eight online lessons is designed for beginning as well as veteran home canners and covers food safety, boiling-water and pressure canning, pickling, freezing, dehydrating, and storage.
The lessons provide the most current USDA approved food preservation recommendations. A certificate of completion is provided at the end of the course.
Visit the host website at the University of Iowa Extension to register for the online series. To participate, you will need a computer made in the last five years and a stable Internet connection. The cost for the series is $25.
Some Washington State counties offer more focused, hands-on classes for those who complete the online lessons. Contact your local WSU Extension office for more information.