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Looking to Darwin to understand soy

Soy is now everywhere in the American diet. Tofu has become a more mainstream ingredient, soy milk crowds dairy cases, and soy fillers and additives can be found in processed foods from soups to meat and vegi-burgers to flavorings like cheese powders. The ubiquitous bean’s high levels of estrogen-mimicking compounds, called phytoestrogens, have long been a topic of scientific study and the nation’s ongoing conversation about nutrition and health. Does eating soy impact our sexual development? Harm women’s reproductive health? Minimize the symptoms of menopause? In a confusing matrix of news reports over the past decade, it’s been reported to both encourage some cancers and protect against others.

Red colobus monkey eating the bark of a eucalyptus tree, a non-native estrogenic species that was planted as a source of fuel wood in Kibale National Park. Photo: Julie Kearney Wasserman
A recent study looks to our biological cousins, non-human primates, for answers.

“Despite great interest in the effects of phytoestrogens on humans and livestock, very little is known about how often estrogenic plants are consumed by our closest-living relatives, so I decided to begin screening the important plant foods of various wild primate species for estrogenic activity,” said Michael Wasserman, a postdoctoral scholar in the Department of Anthropology at McGill University and lead author of the study, who conducted the research while completing his Ph.D. in UC Berkeley’s Department of Environmental Science, Policy, and Management.

Working in lab of Dale Leitman, an adjunct professor in UC Berkeley’s Department of Nutritional Sciences and Toxicology, Wasserman measured the presence of phytoestrogens in the diets of two leaf-eating primate species from Uganda and found that both species routinely consumed estrogenic plants as part of the staple foods in their diets. The red colobus monkey of Kibale National Park consumed more than 10 percent of its diet in estrogenic plants, and in mountain gorilla of Bwindi Impenetrable National Park, studied by his co-author Jessica Rothman, an assistant professor of primate ecology at Hunter College, estrogenic plants comprised nearly 9 percent of the animals’ total diet.

Wasserman is now looking into how these plants affect the red colobus’s endocrine system, which, like ours, regulates many physiological processes and behaviors. He is also measuring the presence of phytoestrogens in the diets of fruit-eating primates, like the chimpanzee, which should yield more information about the relationship between these animals and plants.

As his findings grow, Wasserman hopes the research will shed light on how long humans have been eating estrogenic plant foods over our evolutionary history.

“Throughout most of human history we have lived as hunter-gatherers, consuming large amounts of wild plant foods, especially fruits, and our biology has changed little since these pre-agricultural times,” he said.

By studying chimpanzees, gorillas, and other wild primates that also depend on wild plant foods to meet their nutritional needs, Wasserman hopes to help clarify the importance of dietary niche (fruit- vs. leaf-eater) and phylogeny (ape vs. monkey) to phytoestrogen exposure.

“If it is only the leaf-eaters consuming these plants, then eating foods like soy may be a relatively new trend for us," Wasserman said. "If fruit-eating apes consume estrogenic plants, we have probably been consuming phytoestrogens for millions of years.”

The study is published in the May issue of the American Journal of Physical Anthropology.

Posted on Tuesday, July 17, 2012 at 9:21 AM
  • Author: Ann Brody Guy

Could you please pass me the bug kabobs?

Possibly, people could be divided into the following two groups: those who knowingly eat insects, and those who think they have never eaten them. Since I am still assailed by the odd nightmare in which I am bringing to my lips a well-cooked bug that suddenly springs to life, I decided to tackle my bug-food phobia by visiting entomologist Douglas Yanega of UC Riverside last week.

Yanega has eaten insects, even relished them. With no difficulty whatsoever he has ingested honey bees, termites, mealworms, crickets, grasshoppers, ants, June beetles, silkworms and even scorpions.

Douglas Yanega is the senior museum scientist in the Entomology Research Museum at UC Riverside. He is seen here holding a water bug, an edible insect.
“These admittedly were not very tasty,” said Yanega, who is the senior museum scientist in the Entomology Research Museum, where he studies, identifies and catalogs insects. “In Thailand, however, I had queen weaver ants — a gourmet food there that tastes like either peanut butter or lemon, depending on which body part you’ve sunk your teeth into — and deep-fried mole crickets. Both were delicious!”

Eating insects is not unusual in Thailand, Yanega explained.  Insects, a good source of highly digestible protein, are part of the diet in Korea, China and Mexico as well. 

“You get more bang for the buck when you eat insects, where protein is concerned,” Yanega said. “True, the outer hardened shell is often not digestible, but the softer, internal tissues are. Of course, you want to avoid toxic insects. There are some that could kill you if you ate them.”

How does one know if an insect is toxic? In general, herbivorous insects tend to be more edible. Moreover, insects have evolved to alert other critters — and us! — that they are not suitable for consumption. Bright colors like red, orange or yellow juxtaposed with black on insect bodies are a sure warning from insects that you’d better stay away.

Photo shows monarch butterflies in the Entomology Research Museum at UC Riverside. It is not safe to eat monarch butterflies.
“Think of monarch butterflies, ladybird beetles, tiger moths. You never want to eat them,” Yanega said. “Some tiger moths will even make a noise to warn you to stay away. Other bugs will defensively ooze nasty secretions in your mouth, the moment you bite, to force you to spit them out and free them.”

Because few people experiment with eating insects, identifying those that are both edible and delicious can be a big challenge.

“You have, in the middle of the bell curve of insects, a whole lot that are edible but taste awful,” Yanega said. “And there are those at one end of the curve that are just toxic. But at the other end of this curve lie the prized ones: these are edible and tasty.”

In the United States, most people are culturally still averse to eating insects. If you travel to Mexico, however, you might eat stinkbugs, sometimes used to flavor food. Farther off, in Japan, you could enjoy wasp grubs and silkworm larvae. In the mainland parts of Southeast Asia, you can savor giant water bugs and mole crickets. 

Photo shows water bugs stored in the Entomology Research Museum at UC Riverside. Water bugs are edible.
“In Laos, they eat just about any available insect,” Yanega said. “Some insects are eaten raw, sometimes with small parts removed. Other insects are served deep fried or grilled.”

According to Yanega, one way to get introduced to an entomological diet is to first dry out insects, and then grind them up to a powder.

“You can use this powder as a supplement,” he said. “It’s the easiest way to go about eating insects as food. You can mix the powder into, say, wheat flour to get 'insect-enriched flour.'

If you’re cringing, rest assured that most of us already eat insects unknowingly. Much of food coloring uses insects. The waxy coloring that coats candies is oftentimes insect-based. And a lot of fresh produce has a built-in level of “insect contamination.”

“As long as you are not allergic to an edible insect, you’re safe eating it,” Yanega said. “If you can get past your phobia or stigma of putting bugs in your mouth, you should have no difficulty in adding insects to your diet.” 

Which is what most of us would have to do if we found ourselves stranded on an island and famished.

“Should that happen, never mind the brightly colored bugs,” Yanega said. “Instead, go after the ones that are cryptically colored, the ones that look as though they are hiding from something. They would be a much better bet.”

Posted on Thursday, July 12, 2012 at 8:45 AM

MyPlate revealed: One year later

One year ago in June, the USDA unveiled the new food icon, MyPlate. Based on the 2010 Dietary Guidelines for Americans, MyPlate was created to remind us to make healthy choices at mealtime and to visit the website to get more information. This new, improved and simplified version of MyPyramid was an exciting development for dietitians like myself. No longer would we have to explain to the public what those abstract yet colorful bands represented on MyPyramid. The plate is simple and and gets right to the point, and is a great teaching tool in my opinion.

The beauty of MyPlate is that the graphic is simple, but the website is incredibly rich in information for the public and professionals alike. My favorite feature on the website is the SuperTracker, where you can get a personalized nutrition and physical activity plan. SuperTracker can become your virtual nutrition coach, urging you to meet your health goals through weekly emails.

There is also a great series of handouts called Ten Tips Nutrition Education Series. These free downloadable handouts are created in English and Spanish to help consumers get started toward a healthy diet. There are 20 different topics available now, and even more to come later.

In June, my colleague and I had the pleasure of presenting MyPlate resources and activities to home economics teachers attending a conference in Garden Grove, Calif. We encouraged the teachers to connect with their local UC Cooperative Extension office where the nutrition education professionals have developed creative MyPlate activities to supplement existing nutrition education curricula. 

Hunger Attack Teen Guide
I also knew the home economics teachers would be interested in Hunger Attack. Hunger Attack is part of the MoneyTalks for Teens financial literacy education series developed by UC Cooperative Extension's Consumer Economics specialist and advisors. This resource is designed to teach teens how to make healthier choices and to save money when shopping for food, and has been updated with the MyPlate icon. This resource is made available to educators by visiting the MoneyTalks for Teens website and requesting a password, or contacting the local UC CalFresh Nutrition Education Program or Expanded Food & Nutrition Education (EFNEP) program, both operated by UC Cooperative Extension.

Here's to a successful first year with MyPlate and a job-well-done to the educators and nutrition professionals who have worked so hard to extend these valuable resources to our schools and communities! 

Posted on Tuesday, July 10, 2012 at 8:03 AM
  • Author: Brenda Roche Wolford

Ever explore an artichoke?

Have you ever seen young students explore an artichoke for the first time? Their faces look puzzled as they wonder if this green spiny thing they hold before them is even edible. What about a kiwi? Eyebrows furrow in bewilderment when kids encounter this fuzzy fruit for the first time. Our favorite kiwi quote from a fifth-grade student: “This smells like dirt.”

All jokes aside, in Fresno County, nutrition education is becoming a priority for teachers. The UC CalFresh Nutrition Education Program has worked with over 950 teachers at over 80 schools throughout the county this school year. Our teachers are innovative, and continue to be outstanding in their approach to nutrition education!

While there isn’t enough space to recognize all outstanding educators, we are excited to share a few examples of the ways teachers are going above and beyond to teach students nutrition.

Ayer students learn about edible plant parts.

At Ayer Elementary, kindergarten teachers John Schnell, Donna Johnston, Catherine Uribe, and Nancy Patrick have made healthy eating and active living a priority. They actively take part in nutrition education and monthly tastings provided by UC Calfresh. They often bring in additional healthy foods for the students to sample. Understanding the importance of nutrition in a family-setting, Ayer teachers have invited UC CalFresh to partner in providing kinder parents important nutrition tips to get the year off to a healthy start.  



Balderas students build healthy plates!
Following a lesson taught by a UC CalFresh program coordinator at Balderas Elementary, Mrs. Nunez’s third-grade class created a collage of “Sometime vs. Anytime” foods. Mrs. Nunez went the extra step to reinforce the key concept of enjoying foods in moderation.  Students took the information learned and made “anytime meals.” Students’ artwork was displayed in the hallway for all to see.






Kindergarten students at Burrough Elementary build a healthy breakfast!

“We put our milk in, we take the milk out…and we shake it all about."

It's breakfast time at Burroughs Elementary. Mrs. Mata-Webb’s kindergarten class learned the importance of breakfast through song and dance. Students practiced building a healthy breakfast by including three of the five food groups at breakfast time.




Food Service staff at Viking Elementary
Dedicated to ensuring the health of our students, food service staff in Fresno Unified have also gone the extra mile to help promote our adult nutrition education classes and workshops.

The educators and school staff spotlighted provide a glimpse of the endless examples of excellent nutrition education happening in Fresno County. Statewide, the UC CalFresh Nutrition Education Program is very fortunate to work with such amazing educators. At the University of California Cooperative Extension, we’re working through schools to teach kids good food habits and decision-making skills.

If you would like to have the UC CalFresh Nutrition Education Program at your school contact Shelby MacNab, (559) 600-7222 or smacnab@ucdavis.edu. For additional information, visit our website.

Posted on Thursday, July 5, 2012 at 8:41 AM
  • Author: Shelby MacNab
  • Author: Brittanny Zweigle
  • Contributor: Angelita Zaragoza
  • Contributor: Elizabeth Villalobos

Have a happy, healthy July 4 celebration

Practice food safety to keep the pyrotechnics in the sky and out of your digestive system.
For as long as I can remember, Independence Day has not been about being alone and independent, the Fourth of July is traditionally spent with family and friends, barbecuing, overeating and watching fireworks. Come to think of it, aren’t all American holidays celebrated with abundant quantities of food? And those mass quantities of food tend to be set out on July 4 and left within easy reach for hours.

It’s a wonder July 5th isn’t national foodborne illness day. According to UC food safety experts, food left at room temperature for two hours can become unsafe to eat. If left out in summer heat above 90 degrees, bacteria get busy and can grow to unsafe levels in food in one hour. 

UC Cooperative Extension has a handout online called “The Lunch Box,” which contains tips for making school lunches that don’t deliver foodborne illness. A lot of those tips apply to picnics as well, such as “Keep hot things hot and cold things cold.”

The main foods The Lunch Box recommends be kept cold (40 degrees F or lower) are meat, poultry, fish, eggs, milk, soft cheese and pasta salad, which usually contains mayo. Peeled or cut fruits and vegetables should also be kept cold to deter bacteria growth. Chili, casseroles and refried or baked beans should either be piping hot or chilled. Foodsafety.gov has details for properly preparing, serving and storing various foods.

Brenda Roche Wolford, UC Cooperative Extension advisor in Los Angeles County, specializes in nutrition, family and consumer sciences and pointed me to the Partnership for Food Safety Education website. The partnership recommends four food handling steps to prevent you and your family from suffering foodborne illness and Brenda adds a fifth step:

  1. Clean
  2. Cook
  3. Separate
  4. Chill
    Bonus step: Throw it away

Yes, we must be told explicitly to throw away contaminated food. Most Americans have been told since childhood that we shouldn’t waste food because children in a country that we haven’t visited are starving. I feel the guilt too. Yet, I’d rather chuck suspect food than to be upchucking it later. Those are my words, not Brenda’s. She uses much more professional terms like nausea.

UC ANR has created the “Make it Safe, Keep it Safe” training for employees and volunteers, but it has useful information that anyone can use. The U.S. Food and Drug Administration also has tips for handling food safely when eating outdoors, such as “don’t cross-contaminate.” See the UC Food Safety website for all kinds of food safety information, including publications in Spanish. And if you need some tunes for your party, visit the UC Food Safety Music website to hear “Don’t Get Sicky Wit It,” “Stomachache Tonight,” “We are the Microbes” and many more.

May you have a happy and healthy Independence Day!

Posted on Tuesday, July 3, 2012 at 10:28 AM

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