Weighty Stat

An estimated two-thirds of Americans are deemed overweight or obese. How heavy is that? Astoundingly massive, according to molecular physiologist Ronald M. Evans of the Salk Institute. Sum up all of the excess, he says, and you'll find that the U.S. population is "6.5 billion pounds overweight."

Source: Evans' Fritz Lipmann lecture, this morning, at Experimental Biology '07.

Mushrooming Immunity

Worried about a cold or some other infection? Maybe you should stock up on mushrooms.

These fungi can significantly enhance the body's immune response, according to a pair of fascinating talks I sat through today at the Experimental Biology '07 meeting. Although the reported experiments had been conducted in animals, the researchers acknowledged that their work had been prodded by hopes that the same will hold true in humans. And the fungi that proved especially potent in this regard? Those prosaic white buttons that account for 90 percent of the fungi eaten in the United States.

Dayong Wu and his colleagues at USDA's Jean Mayer Human Nutrition Research Center on Aging at Tufts University in Boston described his group's work with young-adult mice. They added a dry powder made from button mushrooms to the rodents' diet for 10 weeks in quantities that amounted to either 2% or 10% of the animals' meals. Other mice got just the unadulterated chow. When later stimulated with a compound that challenges the immune system, mushroom-treated mice had a more robust response. They produced higher amounts of certain immune agents known as cytokines (including some interferon and interleukin molecules and tumor-necrosis-factor alpha).

The finding suggests that for the elderly or others who might have weakened immune systems, one might enlist mushrooms as a dietary agent to shore up the body's defense against infections.

In a second study, Sanhong Yu and her colleagues at Penn State University tested the ability of five mushrooms widely available in U.S. groceries--including crimini and shitake species--to similarly rev up the immune response of activated macrophages. These are a type of white blood cells that are important immune-system players.

All of the fungi proved helpful, Yu reported. But the really big performer? White button mushrooms!

Yu's team then fed these mushrooms as 2% of the diet to mice for a month and showed that when challenged with a synthetic infection, the animals' immune systems again performed more heroically than if they had been dining on mushroom-free chow.

Who knew? Up to now, I'd always thought of mushrooms as more of a garnish for salads than as a health food.

Bittersweet Stat

Fruits are sweet because they're naturally endowed with sugars. Natural sweeteners lace even milk and various vegetable juices. However, most sugar in the diet has been deliberately added, whether it's to sweeten corn flakes or soft drinks. Boys 14 to 18 years old down the most such added sugar--a whopping 142.6 grams per day, FDA scientists reported today.

That's 21 percent of the energy consumed by boys this age. It amounts to some 570 calories per day, and is equivalent to 35.7 teaspoons of table sugar.

Beverages, especially soft drinks, accounted for most of this added dietary sugar.

Source: Kathleen C. Ellwood, et al. of the U.S. Food and Drug Administration in College Park, Md., at the Experimental Biology '07 meeting, in Washington, D.C.

Health Promotions?

James O. Hill is president-elect of the American Society of Nutrition and director of human nutrition at the University of Colorado. Today, at his society's annual meeting--part of EB '07--Hill floated an interesting idea: Find ways to reward people for moving toward a healthier weight.

Two-thirds of Americans can afford to lose a little--or a lot--of weight, he noted. Clinics can treat the excessively heavy, but don't do much for the simply pudgy. Moreover, even people who successfully shed extra pounds usually put them back on again in the next few months or years. The trouble, Hill said, was society hasn't really crafted effective positive feedbacks, incentive structures that encourage exercise and discourage overeating. At least no feedbacks that were stronger than our biology's innate craving to eat and avoid labor.

One proposal he offered was to have people rewarded in the workplace for staying healthy, such as at a near-optimum weight. He noted that many jobs had a dress code. That's based only as aesthetics. How much better, he suggested, to link career advancement or bonus pay to maintaining health, not just pressed shirts and shined shoes.

An intriguing idea.

But not one, I suspect, that will win much favor.

I can imagine all sorts of lawsuits from people who suffer genetic conditions that affect weight or other health issues. Or who have jobs that compromise health at the same time they're being threatened with reduced compensation for poor health. And who decides what constitutes health...or even the ideal weight for any individual?

Although I support Hill's basic thesis, I guess I'd prefer to see society work out carrots to promote health by individuals--not a battery of sticks.

Tea Time for Fido?

Excess pounds can contribute to the development of insulin resistance, a prediabetic change, in many people. Obesity triggers changes in dogs that are "nearly identical to that seen in the obese human," notes Samuel Serisier of the Ecole Veterinaire de Nantes (France). However, a commercial dietary supplement derived from green tea can restore much of the insulin sensitivity in such animals, he reported today at Experimental Biology '07. a meeting in Washington, D.C.

Serisier's team recruited 10 volunteers. These obese canines had already developed insulin resistance, a condition where their bodies had begun to ignore the presence of insulin--a hormone needed to shepherd energy into cells.

For 12 weeks, six of the pooches received 80 milligrams of a powdered green-tea extract per kilogram of body weight along with their normal day's food rations. The daily supplement provided the animals a dose of catechins--a class of plant-derived antioxidants--equivalent to what humans would derive from drinking 3 cups of tea. The remaining animals received just their normal chow.

At the end of 3 months, insulin sensitivity had improved by 60 percent in the tea-supplemented dogs, Serisier noted; no change occurred in the unsupplemented animals. Green-tea-catechin supplementation had no impact on weight, food-intake, or body composition (i.e. percent body fat and lean tissue). Treatment was linkeed, however, with a 30 percent drop in serum triglycerides, fatty substances that can contribute to clogged arteries.

The findings would seem to offer a simple treatment to boost the health of pudgy pets. Better still, of course, would be to see that man's and woman's best friends get plenty of exercise and a low-calorie diet until they reach their ideal weight. Not only would that also improve insulin resistance, but also ensure that pet owners get off their duffs for a little extra, much-needed exercise.

Finally, don't attempt to treat your pooch with regular green tea. The brew is rich in caffeine, a compound that can prove lethal to dogs.

Fat Stat

Vegetable oils are a type of dietary fat. Did you know that 16 percent of the oil in the typical American's diet--the most from any source--comes from eating potato chips?

Source: Federal data reported today by Jessica Sieber, Department of Nutrition, University of Tennessee, Knoxville, at the Experimental Biology '07 meeting, in Washington, D.C.

Dieting by Dairy

Consuming milk and other dairy products might help people shed unwanted pounds, according to research conducted chiefly--although not exclusively--over the past 7 years by researchers at the University of Tennessee. However, some other studies have challenged the positive findings, leading to the conundrum: Does milk really aid dieters or not?

This morning, the U.S. Department of Agriculture announced it will be weighing in. The agency is commencing a study, which will recruit volunteers for a 15-week trial at its Western Human Nutrition Research Center in Davis, Calif. The men and women must tip the scales at 45 to 100 pounds above their ideal body weight, be healthy, and nonsmokers. The National Dairy Council and Dairy Council of California will be contributing financing for the research.

If you watch much TV, you'll undoubtedly have seen the "Got Milk?" and "24/24" industry campaigns in recent years which have cited the putative weight-reducing benefits of dairy consumption. At least one nutrition-advocacy group--Physicians Committee for Responsible Medicine--has petitioned the Federal Trade Commission over these claims, charging that they "are false and misleading, and in violation of federal advertising guidelines."

I guess Uncle Sam is looking to resolve whether there's merit to research claims--or PCRM's petition.

Do Schools Still Serve Milk?

When my daughter was in elementary school, I pushed and pushed and pushed her to drink more milk. As a nutrition writer, I knew that skim milk would help her bones bulk up on the strengthening calcium they so dearly needed. And reluctantly, she drank what I put in front of her...until middle school, when she really started balking.

She asked why she had to drink so much milk when her friends drank none. I, of course, assumed that was hyperbole. So, I started naming her friends, and in each case she told me that didn't like milk--and didn't drink it.

As an attempt to prove her wrong, I suggested that her science research project that year should involve querying dozens of her classmates about what they drank, how much, and where they consumed it. She passed out the questionnaires, and I sat with her going over the results when she got them back. No one drank more than a glass of milk a day, and those who did probably amounted to no more than 10 percent of the total--3 to 5 youngsters.

My daughter informed me that most days her school didn't even offer milk in its lunch line. I had her interview the cafeteria manager about milk availability and sales. Sure enough, that woman confirmed that her cafeteria didn't always carry milk; so few children wanted it that it wasn't worth taking up the refrigerated space, she told my daughter.

In high school, my child underwent a sudden and miraculous transformation. She started guzzling milk and reaching for heaping plates of fresh fruits and veggies on a daily basis. However, she also noted that she could only get milk at home because her school kept skim milk in the back--only bringing it out on demand. Cafeteria workers, overtaxed by feeding 1,000 students per lunch period each day, were reluctant to make a special trip to get her skim milk.

What did the other kids drink? Soda pop, sports drinks, and sometimes bottled water.

The reason for this post: Yesterday, the Institute of Medicine (IOM) of the National Academies issued a new report, "Nutrition Standards for Foods in Schools--Leading the Way Toward Healthier Youth." In it, the IOM argues that certain foods should be available in schools and their consumption encouraged for youth of all ages. Among these were low-fat or skim milk products. It would restrict sales of caffeinefree and no-calorie soft drinks to high schools--and recommends they be available only during after-school hours. Sugar-sweetened soft drinks and sugar-added fruit juices would be no-no's.

Okay, I grew up in the Dark Ages, when the only drinks available in school cafeterias were one-cup servings of white or chocolate milk. But how did we come to the point where schools have to be told by an august national health organization like IOM that it's time to start offering milk again? Shouldn't they already know this?

Watch Swimming Dinosaurs

Sturgeons are the aquatic world's living dinosaurs. Well, not really dinosaurs--they're fish, after all, not reptiles. But they remain little changed since the time of dinosaurs. A new video now permits many of us to see these ancient creatures in the wild--an increasingly unusual event.

Known primarily as the source of true caviar, these boneless fishes are unusual for a number of reasons--many outlined in a cover story I recently did for Science News. Throughout most of their range, sturgeon species are poorly protected, and as such, are declining to the point of near extinction--in most cases, the result of overfishing.

One notable exception: Wisconsin's lake stugeon.

I started out my March 4 story, last year, describing how sturgeon-conservation managers milked eggs and sperm from fish that were congregating in Wisconsin's Wolf River to spawn. Then, the researchers stirred the newly collected reproductive cells together in buckets and waited for the eggs to fertilize. Later, these would be trucked to hatcheries and incubated through at least babyhood.

To write the story, I spoke with individuals who had taken part in the exercise and had asked them to walk me through the fish catch-and-release event, step-by-step. But I didn't get a chance to see it myself. And although I saw still shots of the fish, I never witnessed their congregating behaviors.

Now you can--and I just have--by watching a short, 4 minute video posted yesterday by Michael Sears, a staff photographer with the Milwaukee Journal Sentinel.

One onlooker in the film describes these sturgeons as the ugliest of fish. I disagree. They've a primative beauty that I find arresting. And Sear's video gives us a chance to witness the primal drive to survive by the one North American sturgeon species (of seven) that's not fairly imminently facing the prospect of extinction.

Before long, we might all get to see the lake sturegon mating behaviors in even greater detail. According to the video, a crew of cinematographers was also present on the Wolf River while Sears was shooting his video. Those others? An IMAX crew getting shots for a film due out in 2008.

Rhino!

Rhinos have it tough. Not only do poachers kill these animals for their horns and hide, but people have increasingly been moving in and converting the shy animals' forested habitat to villages.

On the island of Borneo, an estimated 25 to 50 members of the local subspecies remain. Few had been seen for years--until a motion-sensitive video camera attached to a tree there snapped a small movie of one of these animals.

"This astonishing footage captures one of the world's most elusive creatures," Carter Roberts said Monday, upon the video's release. Roberts is president of the World Wildlife Fund, the group that set up the camera and is now hosting the video on its website.

It's not the first time that such camera traps have confirmed an endangered rhino still exists, even if in perilously small numbers. In 1999, WWF photos of Vietnam's even more endangered rhino--a subspecies thought to number perhaps eight animals, served as the trigger for a Science News cover story on this critter--and efforts to save it.

The story grew from a series of phone interviews--including one to a conservationist in Ho Chi Minh City. He was on a rest-&-recuperation break from his work in the leech-and-tiger-infested national park where photos of the diminutive animal had been snapped.

In any case, take a lot at the Borneo video. It affords a rare glimpse of a majestic creature whose population teeters on the brink of extinction.

Autism Linked to PCBs?

Here's a troubling story that broke today in the L.A. Times. Marla Cone reports that "rats exposed to low levels of PCBs in the womb and during nursing had disorganized, malfunctioning auditory centers. The auditory cortex controls the brain's processing of sounds, which is essential for language development."

Cone cites one author of the new study, which is due to be published online in the Proceedings of the National Academy of Sciences, as saying that "we linked PCBs to an area of the brain that impacts one aspect of autism, language delays or language loss." He goes on to speculate that PCBs might cause a similar rewiring in human brains.

Of course, it's a long way from animal studies to demonstrating human risks. But it does give pause...especially since autism is a devastating disease and scientists still have few clues as to what triggers it, much less how to limit the social isolation it engenders.

Dietary Botanicals

"Americans consume more than $4 billion worth of St. John’s wort, Echinacea, Ginkgo biloba and other herbal products each year in hopes of improving their health, memory and even their sex lives. But are these products effective, or even safe?"

So starts the announcement for the 6th Oxford (Miss.) International Conference on the Science of Botanicals. Scientists from around the world will meet, next week (Apr. 30 to May 3), to share new data on the safety and quality of such plant-based dietary supplements. Among the event's august hosts: the U.S. Food and Drug Administration's Center for Food Safety and Applied Nutrition and the National Center for Natural Products Research, a unit of the University of Mississippi School of Pharmacy.

A program for the meeting is available at: http://www.outreach.olemiss.edu/events/ICSB/index.html . . . then click on agenda.

Surf the Turf

I recently wrote a cover story for Science News titled "Herbal Herbicides." It introduced many of the magazine's readers--including members of my own family--to the concept of allelopathy. This chemical warfare, carried out by one plant species against others, can get pretty brutal. In extreme cases, the soil around an aggressor can become barren of any species other than its own. More often, an antisocial plant may just seed its immediate vicinity with poisons against its primary competitors.

In any case, the story focused on plenty of agricultural examples, pointing to how the harnessing of plants that secrete selective herbicidal poisons might eventually save farmers a small fortune on buying and applying synthetic pesticides. This weed-control strategy would also be good for the environment since the plant-secreted chemicals are released only where and as needed.

Even my dad, more an engineer than science junky, read the piece through to the very end, digesting and absorbing its chemistry. In fact, it was he who drew the story's attention to my sister (a nurse who ordinarily would never read the mag).

Her reaction, minutes later, mimicked that of so many other readers: She wanted more details about Intrigue--the sole horticultural example in the story. I had reported that this turf grass, a commercially available fine fescue, is undergoing field trials by New York State officials because of its innate allelopathic weed resistance.

Cornell University data has just demonstrated, I noted, that such strongly allelopathic fescues "create dense carpets of bright green grass that grow slowly, so they need little mowing. They also resist disease, tolerate shade or full sun, and inhibit at least 20 of the most common urban weeds, thereby needing no help from herbicides." Photos illustrated just how weed repellent such turf grasses have proven.

My sis, like everyone else who contacted me, wanted to know where they could find Intrigue. I had no idea, so I suggested they try scouting vendors via the Web.

But what really pleases me is the reaction most people have had to this example of explanatory journalism, one that has brought an important biological concept onto the radar screens of even Harry and Harriet Homeowner. I know they're jazzed by the idea of low- or no-maintenance lawns. However, while considering this greener approach to turf management, they've also wrapped their heads around some new and very practical science.

Now how cool is that?

Vitamin D and Lead Poisoning

Vitamin D is the everything vitamin--or so it seems. Ample intake has been linked with fighting osteroporosis, cancer, diabetes, gum disease, muscle weakness, autoimmune disease--you name it. The rub: Few people really get ample intake.

It always seemed that more was better. But today I finally ran across a potential drawback to the sunshine vitamin.

It seems that for young children exposed to lead--and the nation's inner cities have many--increasing amounts of D are being linked to increasing body burdens of absorbed lead, a toxic heavy metal that can diminish IQ. To find out more, read the study in the April Environmental Health Perspectives. It was conducted by scientists at the University of Medicine and Dentistry of New Jersey (UMDNJ)-New Jersey Medical School (yes, the school's name really is that long).

John Bogden, an environmental health scientist and one of the study's authors, says the vitamin-lead link was not a surprise. Among its many functions, he notes, vitamin D helps the body absorb calcium. That's why lots of D is good for building strong bones and teeth. Unfortunately, the body responds to lead much as it does to calcium.

The researchers studied 142 low-income black and Hispanic children in Newark, N.J.. over a period of 6 to 7 months. All the kids were between the ages of 1 and 8 . The scientists measured vitamin D and lead in the children in winter and again in summer. Why? Upon exposure to sufficient sunlight, skin can make vitamin D. However, in Newark and other northern cities, sunlight is not strong enough in winter to trigger much if any production of D, so people are dependent on diet for this nutrient. And despite what food and dietary supplement manufacturers tell you, none are making products that are really rich in D. So, Bogden's group reasoned, children might show sharply lower vitamin D levels in winter.

And, in this study, they did.

The surprise, Bogden's group found, was that despite their living in the same neighborhoods and experiencing the same socioeconomic deprivation, Hispanic children in this study had little lead poisoning. For the purposes of this study, that was defined as lead concentrations of at least 10 micrograms per deciliter of blood. The black children, however--especially those 1 to 3 years old--had very high rates: about 12 percent in winter and 22 percent in summer.

The question, Bogden asks, is what underlies this strong ethnic difference? Is it housing? Diet? Access to sunlight? His group will be checking it out.

But the bigger problem, of course, is that these economically disadvantaged kids unwittingly face a Hobson's choice: a trade-off between compromised IQ and all of the health benefits that vitamin D offers.

Tapas Journalism...Pt. 1

As the exponential growth of blogs illustrates, anyone can become a published commentator, if not an outright source of news. The major proliferation of these news streams--many of them unedited and playing fast and free with facts--have been flowing through the Web. Commercial media enterprises, not to be outdone by these upstarts, have been issuing their own Web-based content, most of it free.

For-profit media have felt they've had to post free content--as a sort of loss leader. They want to look hip, for want of a better term. They also pray, with an almost religious fervor, that their freebies will lure in readers, convincing them that their site is worth revisiting regularly. Their hidden agenda: To eventually convince these readers that the content is so valuable that access to it is worth paying for. Or, if the visiting netizens won't pay, but there are zillions of them returning on a regular basis, that perhaps well-healed advertisers will offer to pay for the privilege of erecting the electronic equivalent of billboards on their site.

The idea is a reasonable one.

The problem: The money just hasn't followed.

In some sense, the idea has actually backfired, because the more content that is given away free on the Internet, the more browsers come to expect that all content should be free. Yet producing quality content not only is time consuming and but also benefits from having experienced newsgatherers.

Which raises the question: How do you remunerate newsgatherers for providing that free content?

I ask the question because the venerable newsweekly that I work for--now some 85 years old--is in the throes of reinventing itself. No one on its staff knows how this will play out--yet--although within weeks that should sort itself out. In the mean time, there have been discussions by our outside consultants that perhaps we should at least run the financial numbers to see if cutting back on the frequency of print issues will make us more economical. In doing so, we'd move increasingly more content to the Web--and deliver that electronic news stream more frequently. Most of our Web content is now updated weekly. Should that go to daily? Hourly? By the minute?

Will visitors to the site--and there are already a steady stream of devoted ones--be willing to pay for the extra content? And how will--or should--stories presented on a Website differ from those archived in print?

Some of the "experts" we've heard from argue that Web news accounts should be short, pithy, and lively--in keeping with the short attention spans of multi-tasking teens and 20-somethings. That's the demographic all news organizations salivate over--but seldom capture.

My worry is that such stories could create a culture of what I'm calling tapas journalism. Little bite-size news nuggets or insights. Each a taste of something new and interesting. Appetizers that allow a sampling of diverse and totally unrelated topics.

While that may be appetizing to the Web visitors, it may not offer the balanced diet of well-researched, contemplative, and integrated information that has traditionally been the output of print news operations. In other words, who will reach for the news equivalent of meat or peas and carrots when they can have little tastings of prosciuto-wrapped ham, almond-stuffed olives, curried meatballs, or a few pieces of veggie sushi?

I'm concerned that what would contribute to an informed citizenry could be lost if all we go for is the "interesting."

Don't get me wrong, I love tapas--short, quirky news items. But I also depend upon heavily researched and investigative journalism--the type that draws connections between disparate events or concepts, ones that would not be intuitively obvious. Journalism that documents the facts underlying arguments or charges, so there can be no doubt what is fact versus supposition, inference, or off-the-cuff intepretations by nonexperts.

In theory, the Web could get us all of this and more. And there are some great sites out there--buried within the growing universe of mediocrity and the journalistic equivalent of fast food. What I want to know is: How do we make the Web the destination for serious, responsible, trustworthy journalism--and how do we help readers/viewers on the Web identify this from rehashed or poorly researched drivel?

Can we develop the equivalent of a Good Housekeeping Seal of Approval for solid and reliable Web news and informed opinion? Can we develop Web organizations that help us find these sites?

Care to weigh in?

New Beginning

So begins a new era of Food for Thought.