Posts Tagged: water
Can you help fight the California drought by consuming only foods and beverages that require minimal water to produce?
Daniel Sumner, director of the UC Agricultural Issues Center at UC Davis, and research assistant Nina M. Anderson mine the details of this issue to help us all better understand just what impact our food choices can have on conserving California's precious water.
To begin with, not all water drops are equal because not all water uses impact California's drought, the researchers explain.
So just what water does qualify as California drought-relevant water? You can definitely count surface water and groundwater used for agricultural irrigation as well as water used for urban purposes, including industrial, commercial and household uses.
And here are a few examples of what water is not relevant to California's drought:
-- Water used in another state to produce young livestock that are later shipped to California for food production; and
-- Rain that falls on un-irrigated California pastureland. (Studies show that non-irrigated, grazed pastures actually release more water into streams and rivers than do un-grazed pastures, the researchers say.)
In short, California's drought-relevant water includes all irrigation water, but excludes rainfall on non-irrigated California pastures as well as any water that actually came from out-of-state sources and wound up in livestock feeds or young livestock eventually imported by California farmers and ranchers.
Also, the amount of water that soaks back into the ground following crop irrigation doesn't count – and that amount can be quantified for each crop.
Comparing water use for various foods
I think you're getting the picture; this water-for-food analysis is complicated. For this paper, the researchers examined five plant-based and two animal-based food products: almonds, wine, tomatoes, broccoli, lettuce, milk and beef steak.
In teasing out the accurate amount of water that can be attributed to each food, the researchers first calculated how much water must be applied to grow a serving of each crop or animal product. Then they backed off the amount of water that is not California drought-relevant water, arriving at a second figure for the amount of drought-relevant water used for each food.
They provide a terrific graph (Fig. 3) that makes this all quite clear, comparing total applied water with California drought-relevant water used for the seven food products.
Milk and steak top the chart in total water use, with 1 cup of milk requiring 68 total gallons of water and a 3-ounce steak requiring 883.5 total gallons of water.
But when only California drought-relevant water is considered, one cup of milk is shown to be using 22 gallons of water and that 3-oz steak is using just 10.5 gallons of water. (Remember, to accurately assess California drought-water usage, we had to back off rainwater on non-irrigated pastures and water applied out of state to raise young livestock or feed that eventually would be imported by California producers.)
“Remarkably, a serving of steak uses much less water than a serving of almonds, or a glass of milk or wine, and about the same as a serving of broccoli or stewed tomatoes,” write Sumner and Anderson.
Still skeptical? Check out their paper in the January-February issue of the “Update” newsletter of the Giannini Foundation of Agricultural Economics at http://bit.ly/1XKZxxC.
UC ANR's Nutrition Policy Institute (NPI) has led a push to get the government to make water the drink of choice in the guidelines and add an icon for water on the MyPlate food guide. The guidelines don't go that far, though they do include information that recommends drinking water – in the fine print.
“The guidelines' recommendation to substitute water for sugary drinks is based on solid science. These beverages are the single biggest source of added sugars for our country's kids – and this guidance is explicit and unambiguous and will boost our work in promoting zero-calorie drinking water as the beverage of choice,” said Nutrition Policy Institute Director Lorrene Ritchie. “However, this guidance is presented in a way that gives few Americans an opportunity to see it: on a tip sheet that explains how to use the components of MyPlate ‘to create your own healthy eating solutions — MyWins'. The public health community and the new National Drinking Water Alliance, coordinated through NPI, will build on the potential in this fine-print message by continuing drinking water education, promotion and advocacy.”
The Dietary Guidelines for Americans, updated every five years based on the latest advances in nutritional science, serve as a basis for federal nutrition policy and help set the tone for how Americans should eat. The 2015-2020 guidelines, published this month, recommend a “healthy eating pattern” with limited added sugar and saturated fat, less salt, and more fruits, vegetables and whole grains.
For the first time, the guidelines recommend a clear limit on added sugar of no more than 10 percent of daily calories.
“The science regarding the health risks of a high-sugar diet is strong,” Ritchie said. “Not only is sugar associated with chronic disease risk and obesity, but it also displaces foods known to protect and promote health.”
And what's the simplest way to reduce sugar intake?
“Take a bite out of the added sugars in your diet by drinking plain water instead of sugary beverages,” Ritchie said. “This one simple lifestyle change can be an effective response to the latest nutrition science in the new Dietary Guidelines for Americans.”
Read more UC expert commentary on the new dietary guidelines
An initiative to maintain and enhance healthy families and communities is part of the UC Division of Agriculture and Natural Resources Strategic Vision 2025.
three times the recommended amount of sugar every day, and about half the U.S. population consumes sugary drinks on any given day.
Excess sugar consumption contributes to obesity, tooth decay, early menses in girls, and chronic diseases including diabetes and heart disease. To add to the damage, doctors are now attributing too much dietary sugar to non-alcoholic fatty liver disease, which can lead to cirrhosis of the liver.
It's enough to make you sit up and listen to the warnings about too much soda, sugary drinks, and sugar-laden processed foods.
What is a sugary drink? It's any beverage, more or less, with added sugar or other sweeteners, including high-fructose corn syrup. The long list of beverages includes soda, lemonade, fruit punch, powdered fruit drinks, sports drinks, energy drinks, sweetened coffee and tea drinks, and many flavored milk products.
People are becoming aware of the concerns of too many sugary drinks, and steps are being taken to reduce their consumption. Some K-12 school districts across the nation are limiting sales of soda, and the City of Davis will soon require that restaurants offer milk or water as a first beverage choice with kids' meals.
UC Cooperative Extension, the county-based outreach arm of UC Agriculture and Natural Resources, is partnering with health agencies and conducting public service programs for youth and families about sugary drinks. UC ANR Cooperative Extension in San Joaquin County recently presented a "Rethink Your Drink" parent workshop in conjunction with the county's Office of Education, and Solano County Cooperative Extension is working with the California Department of public health to engage youth in "Rethink Your Drink" programs.
Lucia Kaiser, UC ANR Cooperative Extension nutrition specialist, co-authored a policy brief about California's rural immigrants who have poor-quality tap water, or perceive tap water to be bad. Kaiser, who is also a nutrition faculty member at UC Davis, noted that studies have found a link between water quality and consumption of sugary drinks, which is a concern in low-income communities that don't have resources for clean water.
As of this month (July 2015), UC San Francisco is no longer selling sugary beverages on its campus, and UCSF has launched a Healthy Beverage Initiative. UC Berkeley held a Sugar Challenge this year, and UC Davis is conducting a Sugar Beverage Study on women.
Scientists at UC San Francisco, UC Davis, UC ANR's Nutrition Policy Institute, and other universities are studying the health effects of sugar and implementing health outreach programs. And UC's Global Food Initiative is building on the momentum of excessive sugary-drink consumption.
A healthy alternative to sugary drinks? Water, of course. Many universities and public places are replacing traditional drinking fountains with water stations so that students and others can fill their own bottles and have water “on the go.” And UC President Janet Napolitano is working with the Nutrition Policy Institute on a bold and sensible request to place water on the USDA's MyPlate nutrition guidelines.
The next time you're thirsty, drink wisely to your good health.
- Sugary drinks are hiding under a 'health halo'; UC ANR Food Blog, Aug. 6, 2014
- Nutrition Policy Institute, UC ANR
- UCSF Launches Sugar Science Initiative, a national initiative
- Learn the Facts about Sugar: How Sugar Impacts your Health, UCTV Video, May 2015
- The Hidden Costs of Sugar; UCSF news release, Nov. 2014
- Why Sugar? Why Now?, blog article by Laura Schmidt, UCSF
Food and water scarcity are simply a part of life for most in this region. Since 1992 the Sahelian Solution Foundation (SASOL) has been constructing dams and working with Kitui communities to address water scarcity and issues of community development and agricultural production.
Agricultural production in Kenya is full of challenges. Water is carried by hand from wells or dams for household and agricultural needs. Previous to this mission, crops were watered inefficiently by flooding small basins. Nitrogen tests in some locations revealed levels at which most vegetable crops would be nitrogen deficient. Some of the villages have no road access.
They met with village leaders and SASOL personnel in Kitui. Here they provided training and demonstrations covering topics including:
- Demonstrations of gravity-flow drip irrigation systems from water tanks to individual beds with irrigation lines
- Discussed use of mulches on soil to minimize evaporation and enhance soil conservation
- Solarization, nursery for transplants, diseases and insects, training tomato plants and culture
- Soil types, determination of soil moisture, quick nitrogen test, use of cover crops and mulches
- Water quality (pH, hardness, salts), organic fertilizers, collection and use of urine as a rapidly available nitrogen source.
Later the information was shared in the Maito village, where onions, green kale and green grams (Phasleolus aureus) are grown. The next day found the group in the Kituvwi village, where due to poor crop production, meals are currently limited to once a day. The following day was spent in the Kathayoni village. Farmers in the Kathayoni village grow kale, onions and tomatoes.
SASOL will continue the training for members in villages not reached during this visit.
The majority of farmers in the Kitui District are women. Information was well received in all locations and many questions were asked. At each village the scientists were fed a stew of corn and beans, supplemented by avocado slices or bread, with tea and milk to drink.
The last day time was spent at the South East University College. Potential for agricultural experimentation and greenhouses was discussed, and UC scientists gave a seminar about UCCE function and on anaerobic soil-borne pest control.
In most California homes there are few commodities more precious, or more taken for granted, than clean tap water. We use it without hesitation for drinking, cooking and washing produce.
However, recent news reminds us that not everyone can take clean water for granted. In rural California, where some households rely on well water, up to 2 million people have been exposed to unhealthy levels of nitrates in their water at some time during the last 15 years.
Synthetic fertilizers used in agriculture are major contributors of nitrates to our water, but a growing number of farmers are taking steps to reduce this problem by adopting micro and drip irrigation technologies, and by cultivating noncrop vegetation (buffer strips and cover crops) and “constructed wetlands.” All these measures reduce not only nitrates but many other pollutants from runoff.
"Nitrate problems start when applied fertilizer moves outside the root zones of plants," says Toby O'Geen, UC Davis soil resource specialist. "If nitrate reaches the root zone of actively growing crops, much of it is taken up by roots. But because of its high mobility, nitrate occurring outside the root zones can be transported by irrigation or rain as surface or subsurface runoff. "
Technologies like drip irrigation deliver water and fertilizer precisely to root zones. From 1991 to 2001, Califiornia growers decreased surface irrigation (furrow and flood) about 28 percent and increased sprinkler and drip/microirrigation about 28 percent (Orang et al 2008).
In addition, growers are using buffer strips, cover crops, vegetated waterways and constructed wetlands to purify water, reduce erosion, and remove hazardous contaminants such as pesticides, metals, pathogens and fertilizers. The Farm Bill funds some of these programs through the Environmental Quality Improvement Program and the Wetland Reserve Program.
"Farmers receive technical advice and funding to take marginal land out of production and put it into noncrop vegetation and creation of habitat, including constructed wetlands," O'Geen said.
The effectiveness of such measures depends on the site and the design, but they are probably the best way to reduce water pollution from runoff. (Taking regulatory action against any particular grower is not practical because the sources of nitrate pollution are widespread and occur regionally. Even isotope "fingerprints" often give mixed results because sources mix in the environment.)Another way that agriculture helps remove pollutants of all kinds, including not only fertilizers and pesticides but pathogens, is through natural filtering by rangelands, including oak woodlands. (See details of how oaks help nitrogen cycling.) More than two-thirds of California's drinking-water supply passes through or is stored in oak woodlands. In fact, rangeland in California (land suitable for grazing livestock) comprises more than half of the state's 101 million acres and typically is not fertilized. It forms our major drainage basins – filtering the drinking water for millions of people. (see California Agriculture).