FOR IMMEDIATE RELEASE: July 19,2007
CONTACT: Janet Byron, 510-642-2431 x19 or janet.byron@ucop.edu

Social networks influence growers’ water-quality management

OAKLAND -- Growers are most likely to trust their county’s agricultural commissioner, Farm Bureau and UC Cooperative Extension office for information about water-quality management, according to a peer-reviewed study published in the July-September 2007 issue of the University of California’s California Agriculture journal (http://californiaagriculture.ucop.edu).
      Mark Lubell, UC Davis associate professor, and Allan Fulton, UC Cooperative Extension advisor, surveyed more than 1,200 growers in the Sacramento River Valley about how they make production decisions regarding water-quality management. The surveyed growers had the lowest levels of trust in the U.S. and California environmental protection agencies, and the state water board.
      The survey also found that Sacramento River Valley orchard growers need an average of nine contacts with a “diffusion network” of peers, private advocacy groups and public agencies before they will adopt a new best management practice (BMP) to protect water quality. The authors define a diffusion network as a social system for communicating information about agricultural practices, through both formal and informal connections and interactions. BMPs include sustainable practices such as calibrating pesticide sprayers, providing habitat for beneficial insects, and planting filter strips to control runoff.
      The research has important implications for policymakers and Central Valley growers as they grapple with water-quality regulations. In January 2003, the Central Valley Water Quality Control Board (Region 5) adopted the so-called “Conditional Waiver,” which regulates water quality across a vast swath of California agricultural land. The Conditional Waiver is still contested today; one way that growers can comply is by joining a watershed management coalition, in this case a diffusion network called the Sacramento Valley Water Quality Coalition.
      The survey found that “the more producers interacted with diffusion networks, the more likely they were to be satisfied with watershed management policies, participate in policy activities and adopt environmentally sound practices, as long as they were cost effective,” Lubell and Fulton wrote.

Also: The July-September 2007 issue of California Agriculture includes four peer-reviewed articles on obesity, including a meta-analysis of dietary factors that influence obesity; new research on possible links between food insecurity and childhood obesity in low-income Mexican-American families; new research on an association between overweight and obesity, magnesium deficiency and asthma rates; and case studies of coalitions working to prevent obesity in California communities. Another peer-reviewed study compares the quality characteristics of late-season navel orange varieties.

MEDIA CONTACTS:
Allan Fulton, UC Cooperative Extension water resources advisor for Tehama, Colusa, Glenn and Shasta counties, (530) 527-3101, aefulton@ucdavis.edu
Mark Lubell, UC Davis water policy associate professor, (530) 752-5880, mnlubell@ucdavis.edu.
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Obesity and magnesium deficiency may increase asthma symptoms

Diet can have a significant effect on asthma, according to research reported in the current issue of California Agriculture journal. The evidence suggests that the risk of asthma and the severity of its symptoms may be increased by low intake of magnesium and overweight.
       The research, by postdoctoral researcher Alexandra Kazaks and nutrition professor Judith Stern of UC Davis, also indicates that people who are overweight get less magnesium in their diets.
      “Replacing low-magnesium foods with high-magnesium foods may be a practical, low-cost way to reduce asthma symptoms,” Kazaks says. “It may also improve overall health.”
      Inside everyone’s bodies, there is an ongoing interplay of damaging reactive molecules and antioxidants that neutralize them. The body’s defense systems and the person’s diet provide antioxidants that protect cells from damage, such as inflammation related to asthma. In foods, there are more than 4,000 compounds that act as antioxidants, including vitamins C, E and magnesium. The relative importance of individual nutrients in asthma control is unclear, the scientists write, but magnesium appears to be significant.
      Asthma is a major cause of illness and disability in the United States. Numerous studies show a relationship between low magnesium intake and asthma symptoms, and studies show that intake of magnesium in the general population does not reach recommended levels. In fact, the scientists report, less than half of American adults consume the recommended daily allowance of magnesium, even though it is found in a variety of foods, including whole grains, green leafy vegetables, legumes and nuts.
      The researchers studied a group of Sacramento volunteers, 54 with mild to moderate asthma and 47 who do not suffer from the disease. The subject’s weight and height, dietary habits and magnesium levels were documented.
      “When the subjects were broken down according to their weight and height ratios, it was very clear that the more overweight the subjects were, the more likely they were not eating foods that provide the recommended levels of magnesium,” Stern says. “Further, the asthma subjects who were overweight and obese had significantly lower magnesium than the normal-weight asthma subjects.”
      The findings led the researchers to the conclusion that increasing magnesium intake and losing weight will help control asthma.
      “As a bonus, the foods with magnesium are also part of a diet that supports general good health and healthy weight management,” Stern says.
      The research report is part of a series of articles on obesity that appear in the July-September, 2007 issue of California Agriculture journal, http://californiaagriculture.ucop.edu.
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Examining obesity: What should we eat?

By reviewing thousands of research reports, UC scientists were able to pin down four factors that are most likely to cause overweight and obesity in America: the consumption of dietary fat, sweetened beverages and restaurant foods, and a pattern of breakfast-skipping.
       The systematic review found that intake of protein, simple sugars and fruit juice, as well as food variety, portion size, snacking and frequency of eating, were not consistently related to obesity. The conclusions can help parents and health professional focus their efforts on the prime culprits in their efforts to stop the obesity epidemic currently sweeping the United States.
      “Reports in the press are often conflicting and more often confuse than clarify the issue of what people should eat to prevent obesity,” says lead author Lorrene Ritchie, researcher at UC Berkeley’s Dr. Robert C. and Veronica Atkins Center for Weight and Health.
      Since the 1970s, the prevalence of obesity has doubled among adults and tripled among children in the United States, according to the Centers for Disease Control. In California, more than 4.7 million adults were obese in 2004.
      In addition to avoiding the factors that cause overweight and obesity, the study found that a diet to prevent those conditions would include lots of fiber, fruits and vegetables, and adequate calcium and dairy products.
      Three years were spent systematically analyzing peer-reviewed obesity and nutrition studies published between 1992 and 2003 to isolate the main dietary factors contributing to obesity.
      The current issue of California Agriculture includes four peer-reviewed articles on obesity, including the systematic review by Ritchie and five UC-affiliated colleagues; new research on possible links between food insecurity and childhood obesity in low-income Mexican-American families; new research on an association between obesity, magnesium deficiency and asthma rates; and an article on efforts by UC Cooperative Extension to organize local community coalitions for obesity prevention in California. The July-September 2007 issue also includes an editorial by Patricia Crawford, co-director of the Center for Weight and Health, highlighting the importance of agriculture and nutrition partnerships to more effectively stem rising obesity rates in California, as well as a news article on a wide variety of efforts by UC scientists to address childhood overweight.
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