UC Food Blog
Two years ago, Berkeley voters approved the first soda tax in the country. Folks in Berkeley pay a penny-per-ounce tax on soda and other sugary drinks including sports drinks, energy drinks, bottled sweet tea and coffee drinks. Tax revenues from the first year totaled approximately $1.4 million dollars.
I serve as a member of the Berkeley Sugar-Sweetened Beverage Product Panel of Experts Commission appointed by the City Council. This group is tasked with advising City Council on measures the Council can take to reduce sugar-sweetened beverage consumption and the health impacts of sugar-sweetened beverage consumption in Berkeley.
So far, the City Council has allocated a total of $2 million toward reducing sugar-sweetened beverage consumption and their harmful health impacts. At the recommendation of the experts panel, Berkeley has funded health and wellness activities in Berkeley schools through Berkeley Unified School District's cooking and gardening programming, and a variety of strategies by community agencies to educate residents and increase healthy beverage environments in the city.
Those of us working in the area of nutrition science know that reducing consumption of sugar-sweetened beverages is the most effective way to reduce rates of obesity, diabetes and related health conditions. The greatest source of sugar in the diets of children is sugar-sweetened beverages.
We also now know that the Berkeley tax to date has been a spectacular success. A study published in August by UC Berkeley scientists shows a 21 percent drop in sugar-sweetened beverage consumption in Berkeley's low-income neighborhoods. In comparison, low-income neighborhoods saw a 4 percent increase in sugar-sweetened beverage consumption over the same periodin San Francisco, where a soda tax was defeated in 2014, and in Oakland, which also doesn't currently have a soda tax. The American Beverage Association, which has spent millions of dollars in an effort to defeat various soda tax proposals, opposes soda-tax ballot measures in our communities, and is using advertising campaigns and door-to-door canvassing that spread carefully crafted and misleading messages to voters.
The Bay Area has long been an early adopter of many important ideas, initiating movements that have spread across the country. Will Oakland, Albany and San Francisco follow Berkeley's lead to a healthier future for their communities?
National Farm to School Month. Education and outreach activities such as school gardens, cooking lessons and field trips are teaching students about healthy, local foods and food's journey from the farm to their forks.
There are plenty of opportunities for teachers and schools to celebrate and get involved in National Farm to School Month with the University of California Division of Agriculture and Natural Resources (UC ANR). Here are a few ideas to get you started.
4-H youth development
Launch a 4-H Club at your school. The 4-H Youth Development Program emphasizes enrichment education through inquiry-based learning. Core content areas include Healthy Living as well as Science, Technology, Engineering and Math (STEM). Clubs have access to a wealth of curricula materials exploring food, agriculture and natural resources. 4-H also offers the Ag in the Classroom school enrichment program.
Invite UC ANR academics and program staff to your career day or science fair or to make a classroom presentation. Specialists from Master Gardeners, Nutrition Education, Project Learning Tree, California Naturalist and other UC ANR programs know how to engage and inspire your students.
Some programs, including Project Learning Tree, offer "train the trainer" professional development workshops that equip educators with the skills and knowledge to teach concepts in their own classrooms. Project Learning Tree also provides free activity guides to teachers who attend their workshops. The guides highlight differentiated instruction, reading connections, and assessment strategies and offer ideas to integrate technology into classroom instruction,
Research and Extension Centers
Take your students on a field trip to a UC ANR Research and Extension Center (REC). The nine RECs in California are focal points for community participation and for active involvement in current and relevant regional agricultural and natural resource challenges.
Visiting a REC offers students a unique opportunity to learn about food production through the lens of applied science research in plant pathology, integrated pest management, conservation tillage, water conservation, development of new crop varieties, and much more. Some RECs also host extended education programs such as Sustainable You! Summer Camp and FARM SMART.
The 2016 National Farm to School Month theme is One Small Step, which highlights the easy ways anyone can get informed, get involved and take action to advance farm to school in their own communities and across the country.
Each week will have a different focus:
- Education (October 3-7)
- Healthy School Meals (October 10-14)
- Farmers & Producers (October 17-21)
- The Next Generation (October 24-28)
Join the celebrations by signing the One Small Step pledge then take your own small step to support healthy kids, thriving farms and vibrant communities this October by partnering with UC ANR.
This story en español.
In mid-September in California's Sacramento Valley the weather begins to tease us with the sense that fall is on its way. Interestingly, as the nights drop in temperature so too drops the desire for the fresh fruits we've enjoyed all summer. The melons, peaches, and plums have dwindled or disappeared from hometown fruit stands and our taste buds are being tickled by the site of the golden pears and the multiple varieties of apples newly arrived from local orchards.
Late in September our antennae go up at the sight of the colorful variety of sparkling fresh apples. During the summer months the abundance of fresh fruit might cause us not to reach for an apple, other than to pay attention to the old adage, “An apple a day keeps the doctor away.” The sight of the Washington sticker on the apple changes everything.
It's understood that it takes water to grow the fruit we consume. Something likely not appreciated is that researchers from the University of California and the Washington State tree fruit industry are working to understand the risk that water used to grow tree fruit may pose for human health. Water is a vehicle for bacteria that can cause foodborne illness.
Water quality training seminars for growers that have to comply with new water testing requirements have already begun in Washington with the leadership of UC Davis researchers such as Melissa Partyka, Ronald Bond, and Jennifer Chase and Ines Hanrahan of the Washington Tree Fruit Research Commission. Planning for others is underway in many other regions of the United States. These workshops are spreading the word about proper methods for obtaining accurate water samples in order to be in compliance with regulations in the Produce Safety Rules for the Food Safety Modernization Act (FSMA).
Partyka, a staff researcher and doctoral candidate in the Graduate Group in Ecology at UC Davis, Bond, a water quality researcher and the field research manager, and Chase, a doctoral student in the Graduate Group in Epidemiology, are all in the UC Agriculture and Natural Resources' Vet Med Extension and Water and Foodborne Zoonotic Disease Laboratory, headed by UC Cooperative Extension specialist Rob Atwill, which is within the Western Institute for Food Safety and Security. Dr. Hanrahan has become a valuable partner and liaison to the tree fruit industry, helping to both organize and staff the inaugural workshops while advocating for greater collaboration between UC Davis and Washington State University Extension.
The UC Davis team of Partyka, Bond, and Chase, have been in Washington State conducting research and workshops, which will help answer key questions for the tree fruit industry. For instance, whether growers can sample cooperatively and the impact of hold-times on testing accuracy. The trio are members of the Western Center for Food Safety, (WCFS), a Food and Drug Administration Center of Excellence, tasked to conduct research directly related to the FSMA food safety rule for agriculture water.
Bond, Chase and Partyka are featured in an article titled “Simple steps for water sampling” published in the July issue of Good Fruit Grower Magazine. The article, which helps demystify sampling for regulatory compliance, was based on interviews held during the agricultural water quality workshops conducted by these three in Washington last May. The main article is accompanied by two additional guides: one titled “The math of food safety,” explaining the math required for agricultural water testing and “Water sampling 101,” a simple list of dos and don'ts for water sampling.
The rows of corn stalks have dried in the summer sun. The harvest moon will soon greet us in the evening sky. As our senses tingle with the oncoming change of season, the sound of the crunch of a juicy apple is music to our ears. Is it time to start melting the caramel?
One in five Mexican-American children is obese, according to national statistics. While scientists agree that diet and exercise play a role in obesity, studies also suggest that children who don't get enough sleep may also be at increased risk for obesity. Does this mean that children who don't get enough sleep are more likely to become obese due to poor eating habits and being less physically active?
The National Institutes of Health has awarded $895,620 to Suzanna Martinez, Ph.D., assistant researcher for UC Nutrition Policy Institute (NPI) in the UC Division of Agriculture and Natural Resources, to try to answer that question. This will be the first pediatric study to examine health behaviors that link sleep to obesity in Mexican-American children.
Studies have shown that adults who are short on sleep may experience a change in metabolism and hormones, causing the person to eat more and to be more sedentary the following day.
To explore how sleep affects child obesity, Martinez will examine social and cultural factors that may impact Mexican-American children's sleep and, in turn, how sleep affects their diet and physical activity.
“Some researchers just focus on diet, some researchers just focus on physical activity, while other researchers say it's all about the environment so we have to improve the environment in terms of food environment and opportunities to be active,” Martinez said. “There's very little research that tries to target all three aspects of health behavior – sleep, diet and physical activity – because there are so many factors to consider. We have to know which will make the biggest impact on obesity prevention. Is it sleep, diet or physical activity or a combination of all three?” Currently, programs are heavily focused on diet and/or physical activity.
Social and cultural factors may affect sleep
Martinez is essentially combining three different studies into one to evaluate the context of sleep and how it impacts obesity. The five-year study will occur in two phases.
She'll begin by looking at the culture, environment and socioeconomic status of the Mexican American families to see which factors may relate to sleep duration.
For example, Martinez said, “If less acculturated Mexican-American parents have stricter or earlier bedtimes for their children, is that protective for getting optimal sleep, less protective or does it even matter?”
Living in crowded housing or in neighborhoods with high crime, homelessness and drugs can impact sleep for urban Latino families, Martinez learned from interviews with Latino parents for a study she published in 2015.
Sleep and physical activity and diet
The second phase of the study will involve evaluating the sleep duration of 40 Mexican American kids, ages 8 to 10, in the San Francisco Bay Area over two summers.
To record their sleep and physical activity, the participating kids will wear accelerometers during the day and while they sleep. The small, pedometer-like devices are worn on a belt around the hip.
For the first week of the three-week study, the children will be asked to get their normal sleep. During the second week, half of the children will be asked to sleep for less than 8 hours and the other half will be asked to sleep at least 10 hours. The third week, the two groups will switch over to the other sleep schedule.
Their diets will be measured using 24-hour dietary recalls. On Friday and Saturday, children will be asked what he or she ate the day before (Thursday and Friday). Starting with breakfast, the children will report what they ate and drank for meals and any snacks.
Martinez will evaluate whether healthy sleep or restricted sleep the previous night impacts the children's diet and physical activity the next day.
“With the crossover study, we will be able to see how kids compare when they get their usual sleep, healthy sleep or not enough sleep and how that impacts how much they eat and how much they move the next day,” she said.
No U.S. sleep guidelines
To maintain a healthy weight, U.S. Office of Disease Prevention and Health Promotion recommends that children get at least 30 minutes of physical activity daily and the Dietary Guidelines for America recommend that children eat a nutrient-dense and calorically balanced diet. The government office currently has no national sleep guidelines for Americans.
In a 2014 study, Martinez found that 82 percent of Mexican-American children ages 8 to 10 obtained less than the 10 to 11 hours of sleep the National Sleep Foundation recommended before 2015. Under the network of sleep researchers' new sleep recommendation of 9 to 11 hours for this age group, 20 percent of children received less than adequate sleep.
“There needs to be more research on sleep duration before we can say, ‘Sleeping this amount of time will help prevent obesity,'” Martinez said.
If her hunch is correct, promoting optimal sleep (at least 10 hours for school-age children) may be an effective way to reduce childhood obesity, and understanding the role of culture in obesity among Mexican-American children who have some of the highest rates obesity will be a key to designing effective solutions.
Research has shown that obesity contributes to numerous lifelong health problems, including heart disease, stroke, diabetes and high blood pressure. One in four overweight children become obese as an adult, and diseases like diabetes are presenting earlier than adulthood. National data show that 14 percent of white children are classified as obese, while 21 percent of Latino children are obese. With Latino children at increased risk, Martinez is committed to finding the causes of this disparity and to develop effective ways to reduce obesity among Mexican-American children.
This child obesity study is funded by a K01 Career Development Award from the National Institutes of Health National Heart, Lung and Blood Institute. Martinez has also been accepted into the K Scholars Program at UC San Francisco, which will provide her with peer support and mentorship to conduct the study.
On a recent late-summer Wednesday, a freight container filled with cases of expired Muscle Milk protein drink awaited unloading at the UC Davis Renewable Energy Anaerobic Digester (READ) while a front-loader scooped heaps of spoiled vegetables into a mechanical processor. Nourished by a diet of assorted food waste from the UC Davis campus and area restaurants and markets, READ harnesses the activity of billions of microbes to produce biogas capable of generating 5.6 million kWh per year of clean electricity for UC Davis.
But a by-product of READ and other anaerobic digesters – the slurry of leftover solid and liquid material, or digestate – has caught the attention of UC Davis researchers interested in “closing the loop” on food production, consumption, and waste. When processed through an anaerobic digester, organic materials like food discards, expired or off-spec food products, or animal manure can be transformed into concentrated biofertilizers and soil amendments that are highly effective and easily applied to crops.
In an interdisciplinary collaboration at the Russell Ranch Sustainable Agriculture Facility, funded by the California State Water Resources Control Board and the California Department of Food and Agriculture, UC Davis faculty and students have developed a pilot-scale process for commercial production of several forms of this biofertilizer using digestate from READ and other nearby digesters. They are also evaluating their effects on yield and other agronomic metrics in corn and tomato field trials – paving the way for farmers and growers to take advantage of a highly sustainable source of plant nutrition.
The challenge and opportunity of fertilizer from anaerobic biodigesters
The digestate from READ and other digester facilities can be applied directly to soil as a fertilizer, but, because it has a limited shelf-life, it usually must be applied to land in the immediate region of the facility. With the input of food waste that can vary widely from day to day, a facility's digestate is inconsistent in texture and composition, making it difficult to transport and apply to fields using common farm fertilizer equipment.
Filtering and drying this digestate, however, results in solid and liquid forms that can be concentrated, homogenized, easily transported, and applied to soil through existing drip irrigation systems or surface spreading equipment.
This process could allow farmers and growers located further away, and working with common irrigation and fertilizer application equipment, to supplement or replace their synthetic fertilizer consumption with biofertilizers from food waste or animal manure.
How do biodigestate products measure up to synthetic fertilizers?
The research, co-led by professor Ruihong Zhang from the UC Davis Department of Biological and Agricultural Engineering (who also designed READ in partnership with Sacramento-based tech company CleanWorld) and Professor Kate Scow from the Department of Land, Air, and Water Resources, developed pilot-scale systems to efficiently and consistently separate the solid and liquid portions of food- and manure-based digestates. The researchers then examined the nutrient composition of the solid and liquid biofertilizer products, finding that biodigestate-based fertilizers contain valuable nutrients and microbes not found in many synthetic fertilizers.
In current field trials, the researchers are investigating the effects of each of the biofertilizer products on crop yield and quality. Their preliminary results show that it is possible to grow irrigated processing tomatoes and short-season corn using biofertilizer products as the sole source of fertilizer. The origin of the fertilizer matters, however – manure-based liquid fertilizer formed additional large particles after the final filtration, creating concerns about clogging the drip irrigation system. The team thinks an environmentally benign chemical sometimes added to manure digesters to clean the biogas may be the culprit of the problem, but future research is needed. The solid biofertilizer pellets they developed show much promise, as they can be applied using existing methods for spreading compost and can be economically transported farther away from the digester.
In addition to better understanding the best processes for producing and using the biofertilizers, further research is needed to understand how much of the nitrogen in each of the fertilizer products is available for uptake by the crop, as well as economic analyses to determine the commercial-scale production and transportation costs. The researchers will be able to narrow in on the agronomic and economic potential of biofertilizers through the upcoming analysis of the yield of the corn and tomato experiment plots at Russell Ranch. The results of a tomato experiment recently showed that the digestate fertilizers produced just as much fruit as a popular synthetic fertilizer.
Interdisciplinary research for agricultural innovations
Russell Ranch, a program of the Agricultural Sustainability Institute, is designed as a shared space for interdisciplinary research and innovation. The biofertilizer research, among other active projects at Russell Ranch, is an example of the fulfillment of that intention. “The soil scientists are learning engineering, the engineers are learning biology, and the biologists are learning about soil,” Professor Zhang remarked.
The exchange also extends beyond the university: a recent UC Davis Biofertilizer Field Day drew attendees from the UC Division of Agriculture and Natural Resources, several public agencies, the agricultural sector, other universities, nonprofits, entrepreneurs, and food processors. If the research continues to illuminate a way forward for biofertilizers, these audiences may fill important roles in bringing this new technology into practice – and in recycling your lunch leftovers back into a more efficient and sustainable food system.
More information: UC Davis READ, Russell Ranch, and the biofertilizer research
The UC Davis Renewable Energy Anaerobic Digester was unveiled in 2014 as the nation's largest anaerobic biodigester on a college campus, and represented a unique private-public partnership. Professor Ruihong Zhang invented the anaerobic digestion technology used by CleanWorld, which developed it into one of the most advanced commercially-available digester systems in the country.
Russell Ranch Sustainable Agriculture Facility is a “living laboratory” for interdisciplinary field research and innovation. Its flagship project, the Century Experiment, measures the long-term impacts of energy, water, carbon, and nitrogen inputs on agricultural sustainability in the flagship Century Experiment.
The biofertilizer research collaboration includes Zhang Lab graduate students Tyler Barzee and Hossein Edalati, Scow Lab postdoctoral researcher Daoyuan Wang, and Russell Ranch manager Israel Herrera. Collaborating institutions include CleanWorld, California Bioenergy, New Hope Dairy (Galt, CA), Fiscalini Dairy (Modesto, CA), and Sacramento Municipal Utility District.
This story en español.