Wednesday, October 13th, 2010
In a fascinating new article in PLOS One (open access), Daniel Nettle asks why we see social gradients in preventative health behaviors:
People of lower socioeconomic position have been found to smoke more, exercise less, have poorer diets, comply less well with therapy, use medical services less, adopt fewer safety measures, ignore health advice more, and be less health-conscious overall, than their more affluent peers. Some of these behaviors can simply be put down to financial constraints, as healthy diets, for example, cost more than unhealthy ones, but socioeconomic gradients are found even where the health behaviors in question would cost nothing, ruling out income differences as the explanation.
Socioeconomic gradients in health behavior are not easily abolished by providing more information. Informational health campaigns tend to lead to greater voluntary behavior change in people of higher socio-economic position, and thus can actually increase socioeconomic inequalities in health, even whilst improving health overall. Thus, we are struck with what we might call the exacerbatory dynamic of poverty: the people in society who face the greatest structural adversity, far from mitigating this by their lifestyles, behave in such ways as to make it worse, even when they are provided with the opportunity to do otherwise.
What are some of the possible explanations for this pattern, and are they sufficient?
Underlying socioeconomic differences in health behavior are differences in attitudinal and psychological variables. People of lower socioeconomic position have been found to be more pessimistic, have stronger beliefs in the influence of chance on health, and give a greater weighting to present over future outcomes, than people of higher socioeconomic position. These explanations seem clear.
However, they immediately raise the deeper question: why should pessimism, belief in chance, and short time perspective be found more in people of low socioeconomic position than those of high socioeconomic position? These deeper questions are at the level which behavioral ecologists call ultimate, as opposed to proximate causation
To develop more of an ultimate explanation, Nettle hypothesized that lower socioeconomic groups are subject to greater hazard or environmental harm or even simply the perception of living a more hazardous life. This, in turn, discourages healthy behavior.
To test this hypothesis, he developed a mathematical/statistical model predicting the probability of dying in a given year, which is a combination of extrinsic risks that people cannot control as well as intrinsic risks that they can control through modified health behavior. Thus, people choosing to take the time to engage healthier opportunities reduce their mortality risk. Now there’s a tradeoff, however, because the more time people choose to undertake healthy behavior, the less time is left over for leisure activities and other life events.
Overall survival is therefore a combination of all of these factors, which can easily be modeled by assuming a range of values for time spent on health vs. other activities to see what kinds of mortality outcomes arise.
Here are the interesting results he found…
Sunday, September 26th, 2010
The NY Times and Huffington Post are running a story by Kim Severson, Told to Eat Its Vegetables, America Orders Fries, lamenting how hard it is to get people to eat healthy.
The thing that struck me about this article, as its title suggests, is how nutrition in America is often pitched top-down. A strategy is bound to fail when it consists simply of government experts making recommendations about nutrition, as one of the folks interviewed notes:
“It is disappointing,” said Dr. Jennifer Foltz, a pediatrician who helped compile the report. She, like other public health officials dedicated to improving the American diet, concedes that perhaps simply telling people to eat more vegetables isn’t working.
…The government keeps trying, too, to get its message across. It now recommends four and a half cups of fruits and vegetables (that’s nine servings) for people who eat 2,000 calories a day. Some public health advocates have argued that when the guidelines are updated later this year, they should be made even clearer. One proposal is to make Americans think about it visually, filling half the plate or bowl with vegetables.
The article explores the usual things claimed to be preventing people from eating better—convenience and cost:
“The moment you have something fresh you have to schedule your life around using it,” Mr. Balzer said.
In the wrong hands, vegetables can taste terrible. And compared with a lot of food at the supermarket, they’re a relatively expensive way to fill a belly.
“Before we want health, we want taste, we want convenience and we want low cost,” Mr. Balzer said.
Melissa MacBride, a busy Manhattan resident who works for a pharmaceuticals company, would eat more vegetables if they weren’t, in her words, “a pain.”
“An apple you can just grab,” she said. “But what am I going to do, put a piece of kale in my purse?”
“It’s just like any other bad habit,” he said. “Part of it is just that vegetables are a little intimidating. I’m not afraid of zucchinis, but I just don’t know how to cook them.”
The solution is presented as a problem of overcoming access to good food:
But clear guidance probably isn’t enough. Health officials now concede that convincing a nation that shuns vegetables means making vegetables more affordable and more available.
I’m a fan of nutritional literacy, as I am with environmental literacy, but only as one of several approaches in a portfolio of strategies for improving the quality of life and the environment. Nutritionists and climate change educators should team up in this regard because they face the same challenge—winning hearts and minds (or, in this case, stomachs) and changing behavior.
The problem is that a top-down nutritional literacy approach, by itself, is woefully inadequate (more information, alone, simply won’t accomplish this), and access to good food is only part of the challenge.
If you want engagement, then nutrition needs to be turned into a bottom-up venture. It’s not simply a matter of food pyramids and access to good food. People need to experience growing and cooking their own food. They need to be engaged with how good it can be, how it can be grown cheaply, and how plant-based diets are easy to prepare.
There are several ways to begin accomplishing this:
1. Start early. Make gardening and cooking a part of the elementary school experience. All kids should take an active role in planting, tending, and harvesting food. Then they should take part in preparing the foods they have grown in ways that are appealing to eat. The power of this should not be underestimated. The only thing I remember from kindergarten is making bread and butter from scratch.
2. Diffuse this knowledge to home or community gardens. When kids are taught how to prepare healthy, tasty food, they can bring what they learn home, starting home gardens and helping out with making dinner by showing parents what they learned in school (maybe accompanied by some kind of creative incentive from parents to do this). People can see for themselves that is is often less expensive to grow healthy food, especially if communities team up and share their bounties, than it is to buy junk food that makes up much of their diet.
3. Involve the community in a contest to generate a list of the most popular recipes for different fruits and vegetables. Perhaps engage the help of local chefs for fun. I have a 100% whole fruit smoothie recipe that most kids would mistake for dessert.
4. Disperse these recipes widely and incorporate them into school education programs and lunches, as Alice Waters is accomplishing in California.
5. Not only should farmers markets accept SNAP (food stamps), there should be classes/demos to show people how to prepare foods. Also, having samples and recipes that are tasty and convenient would be helpful. People should be convinced, by seeing with their own eyes and taste buds, that they can do this and that it’s worth their time.
And that’s part of the larger problem: overcoming the psychological barrier that fresh food prep is time consuming:
“The moment you have something fresh you have to schedule your life around using it.”
Although I see the point here, I think it’s a poor reason for not eating healthy. People schedule time around education, sleeping, exercising, soccer practice, vacation, being with friends, spirituality, and visits to the doctor/dentist because these things are considered necessary to living well. Is preparing healthy food not a similarly meaningful part of our lives? Is it really impossible for families to schedule 30-45 minutes preparing meals? Should leisure time or other competing interests really be that high an opportunity cost?
Perhaps that’s one lesson: So long as Americans treat preparing and enjoying healthy meals as a tradeoff with leisure time or other activities, American diets will suffer. No amount of top-down government nutrition guidelines will overcome that.
Related news: Bill Clinton now eats vegan
Photo credit: hellochris
Sunday, September 19th, 2010
Laura Miller at Salon reviews a new book out this week by Judy Pasternak titled, “Yellow Dirt: An American Story of a Poisoned Land and a People Betrayed.” A few excerpts from Miller’s analysis:
In the summer of 1979, an earthen dam over the town of Church Rock, Utah, broke, flooding the arroyo below and then the bed of the Rio Puerco (an intermittent stream) on the southern border of the Navajo Nation. It was a small flood, but a dangerous one. It burned the feet of a boy who stepped into it, and caused sheep and crops along the banks to drop dead. That’s because the pond it came from had been used by a nearby uranium mine to store the tailings (residue) of its excavations — the water kept the radioactive dust from blowing away. The 93 million gallons of contaminated water that poured into the Rio Puerco remains the largest accidental release of radioactive material in U.S. history, bigger than the notorious Three Mile Island reactor meltdown that occurred 14 weeks later.
The Church Rock flood is only one incident among many in the “slow-motion disaster” investigative journalist Judy Pasternak comprehensively recounts in her chilling new book, “Yellow Dirt: An American Story of a Poisoned Land and a People Betrayed.” Based on a prize-winning four-part series she wrote for the Los Angeles Times, “Yellow Dirt” begins during World War II, when secretive government surveyors first appeared on the remote reservation, supposedly looking for deposits of an ore called vanadium, used to strengthen steel needed for the war effort. Uranium was the real prize, and after the bombings of Hiroshima and Nagasaki and the ramping up of the Cold War, the American demand for the radioactive substance boomed.
The Navajo Nation and the area around it contained some of the richest deposits of uranium ore in the world, and certainly the most conveniently located. For about a decade, various corporations and government agencies reaped 1.4 million tons of uranium ore from the Monument Valley region alone; Pasternak makes a single mine there, known as Monument No. 2, her primary focus. The mining operations were relatively rudimentary, and by ordination of the tribal government, worked almost entirely by Navajo men. Even the cheapest and most elementary safety practices, such as wetting down blast areas to keep the miners from breathing toxic dust, were neglected in the rush to satisfy the Atomic Energy Commission’s insatiable appetite for uranium.
By the 1960s, the need tapered off, and the mining companies blithely abandoned the sites, leaving piles of radioactive tailings lying around for Navajo kids to play on and their parents to scavenge for conveniently sized rocks with which to build houses, ovens and cisterns. The dust and gravel made seemingly excellent concrete for floors. Monument No. 2, once a mesa, had been nearly leveled, its uranium-laced innards exposed to the open air, reduced to what Pasternak characterizes as a “radioactive pit.” Old quarries filled up with rain- and groundwater, new “lakes” from which local residents watered their herds and gratefully drank.
The next boom, unsurprisingly, was in cancer rates (previously so low among the Navajo that they were thought to be miraculously immune to the disease), and in a birth defect, christened “Navajo neuropathy,” that caused children’s fingers to fuse together and curl into claws. Still, it took decades for the cause to be fully recognized and even longer for it to be addressed; it wasn’t until 2008 and under the lashing of Rep. Henry Waxman, that the federal government made serious efforts to clean up the mine sites, purify water supplies and relocate families living in houses built from radioactive materials.
Read the rest of the review here.
Photo Credit: Christopher Isherwood
Sunday, September 5th, 2010
Mitigating climate warming is going to require a dramatic decrease in carbon emission from the transportation sector, through a combination of driving less, using public transportation, and, eventually, switching to electric cars powered by a renewable grid.
There are many urban centers with outstanding public transportation options, but let’s face it— It’s often more difficult to find alternatives to driving in smaller towns and suburbs.
Brunswick, Maine (home to Bowdoin College) is no different than most small towns (population 25,000). Transportation is one of the largest sources of carbon emissions, and the physical dislocation of residential areas, shopping centers, supermarkets, and hospitals makes it difficult to avoid automobile use. And roads around here are definitely not bike friendly!
This is starting to change as a result of collaborations across institutions from the local to federal levels.
The town just added a new program called Brunswick Explorer, with a fleet of hybrid electric buses that are wheelchair and bike accessible. The route takes the buses from major residential areas (especially those serving the elderly) to our local supermarkets, hospitals, and shopping malls.
With the extension of the Amtrak Downeaster from Portland to Brunswick in 2012, folks will also be able to travel to Portland and Boston easily by train, especially during rush hour and winter when travel by roads is either a hassle or dangerous.
The Explorer and Downeaster are certainly no silver bullets, but they accomplish a few important goals:
These are small steps, indeed, but they have the ingredients to be successful: alternatives to personal vehicle use that are both cheap and convenient, with substantial community buy in.
Photo courtesy of Bowdoin College
Monday, April 19th, 2010
I remember driving on a freeway in Phoenix after midnight in 1990. The temperature was a cool 102 degrees F after breaking the all-time heat record of 126 F that day. Deserts are good at cooling off at night. But with all of the built environment in Phoenix storing heat from the day, the sidewalks, roads, and even swimming pools felt like they were being heated.
We all have probably experienced urban heat islands—the mass of dark asphalt and concrete absorbing solar radiation and radiating it back to space as heat. The lack of water exacerbates the situation because there is little-to-no evaporative cooling. Waste heat from cars, machines, air conditioners, and even human bodies also heat up the air. And the warmer it gets, the stronger the tendency to crank up the air conditioners, generating even more waste heat.
The problem is potentially large in areas like the Middle East, India, parts of Africa, and the American Southwest, where rapid urbanization in warm, dry environments has the potential to make some urban areas much warmer at night than surrounding rural areas.
In a forthcoming article in Geophysical Research Letters1, Mark McCarthy and colleagues at the Met Office, Hadley Centre, UK used a climate model that examines what climate might look like in a doubled CO2 world and calculates the added warming caused by urbanization and wasted heat.
Their results were eye-opening:
As mentioned in an earlier post, we only need to remember Chicago in 1995 to recall the deadly impact that heat waves can have on urban people. And as we saw in that unfortunate example, the victims were disproportionately the elderly and African American.
Although we may not be able to mitigate this warming, basic adaptation steps should be set into motion, including re-thinking urban design, making cities more resilient to hot environments, developing better energy and technology solutions (including cooling), installing green roofs, and putting into place emergency disaster plans and social safety nets for vulnerable populations.
1Mark McCarthy, Martin Best, and Richard Betts (2010). Climate change in cities due to global warming and urban effects Geophysical Research Letters : 10.1029/2010GL042845
Sunday, March 21st, 2010
As we saw in a previous post, food aid is a complex issue. On one hand, it’s critical for acute crisis situations where people are starving because of things like war and natural disasters. On the other hand, in more chronic situations of malnutrition, food aid and cheap imports have the capacity to undermine local food production, which, in the long run, harms the prospect of people feeding themselves through local production.
A farmer’s worst enemy is free food and cheap imports.
In recent years, we have seen this play out in Africa, as Oxfam acknowledges. MSNBC is running a story today, “With cheap food imports, Haiti can’t feed itself,” about how the same thing has happened there. Worth reading.
There is also a larger debate at play here about the implications of free trade and industrialized food production.
Wednesday, December 2nd, 2009
Think of all the reasons why people advocate sustainable food, and the following things probably come to mind:
How about this one?
Not so much.
And that’s probably why Caitlin Donohue wrote the story, “Out of reach: How the sustainable local food movement neglects poor workers and eaters” in today’s San Francisco Bay Guardian Online.
There’s a lot more that can be written on this topic, and there are a growing number of success stories, including
The introduction to Donohue’s article frames the cultural disconnect:
On a sunny afternoon in Civic Center Plaza, a remarkable bounty covered a buffet table: coconut quinoa, organic mushroom tabouli, homemade vegan desserts, and an assortment of other yummy treats. The food and event were meant to raise awareness about public school lunches, although it was hard to imagine these dishes, brought by well-heeled food advocates, sitting under the fluorescent lights of a San Francisco public school cafeteria.
The spread was for the Slow Food USA Labor Day “eat-in,” a public potluck meant to publicize the proposed reauthorization of the Child Nutrition Act, national legislation that regulates the food in public schools. The crowd was in a festive, light-hearted mood. There was a full program of speeches by sustainability experts and a plant-your-own-vegetable-seeds table set up in one corner of the plaza.
A bedraggled couple who appeared homeless made their way through the jovial crowd and started scooping up the food in a way that suggested it had been a long time since their last roasted local lamb shish kebob.
Their presence shouldn’t have been a surprise; most events involving free trips down a food table are geared toward a different demographic in this park, which borders the Tenderloin.
In a flash, an event volunteer was on the case, nervous in an endearingly liberal manner. “Sir,” she began. “This food is for the Child Nutrition Act.” And then she paused, searching for what to say next. I imagined her thinking: “Sir, this food is to raise awareness about the availability of sustainable food to the lower classes, not to be eaten by them,” or, “Sir, this good, healthy, local food is not for you.”
Continue reading here…