A whole wall of Diet Coke.

Sugar-free diet soda has gotten a free pass in the recent debates on soda regulation, covered in Monday's Econundrum. Proponents of soda bans or taxes have attacked Big Gulps and other giant drinks sweetened with sugar or high fructose corn syrup, but DIET COKE devotees may want to hold off on gloating. A new study found that diet soda drinkers had altered brain responses to saccharin (Sweet'N Low) compared to nondrinkers.

Diet soda may be bad precisely because it has no sugar and fewer calories. When you eat something sweet, researchers have argued, your body comes to expect a caloric boost. Low or no calorie artificial sweeteners could screw up this link in the brain.

Researchers at the University of California-San Diego and San Diego State University recruited 24 participants, half of whom drank diet soda regularly, and imaged their brains responding to a squirt of water flavored with saccharin or sugar water. Artificial sweeteners taste sweet, but they don't quite taste like real sugar. Researchers using fMRI, an imaging technique that tracks blood flow in the brain, see a different response to sugar than to sweet substitutes like sucralose (Splenda) and, in this study, saccharin.

In diet soda drinkers, however, the right orbitofrontal cortex of their brains could no longer distinguish between real sugar and fake sugar. In addition, there was decreased activation in an area called the caudate head. The more often the participants reported drinking diet soda, the less activity in this brain area, and the study authors had previously linked decreased activation in the caudate head to obesity.

Residents and volunteers form a barricade at Riverdale Mobile Homes Park in Jersey Shore, Pennsylvania.

When the 32 families of the Riverdale Mobile Home Park in Jersey Shore, Pennsylvania, found out that they were losing their homes to the state's latest fracking operation, the news didn't come from their landlord, or an eviction notice in the mail—they read about it in their morning paper.

The February 18 article, published in the Williamsport Sun-Gazette, nonchalantly detailed the approval of three natural gas projects in Lycoming County, PA, including a water withdrawal station that would pipe millions of gallons of water from the Susquehanna River to fracking stations in the mountains further north. The article noted that an "added benefit" of the plans was "the removal of mobile homes," which were located in a potential flood plain.

Later that afternoon, Riverdale's landlord came by and confirmed what residents had already read in the paper: The property had been sold to Aqua America, a water company dedicated to fracking. The full magnitude of the blow came days later, when the eviction notices arrived, informing the residents that they had until May 1 to relocate so that work on the site could begin in June. Each family was offered $2,500 if they got off the property by April 1; $1,500 if they moved by May 1; and zero compensation after that. It wasn't nearly enough; lawyers for Riverdale residents later estimated that the cost of moving each trailer was, on average, between $8,000 to $10,000.

Cotton bolls in the field

Genetically modified Bt crops get a pretty bad rap. The pest-killing Bacillus thuringiensis (Bt) bacteria protein these plants are bioengineered to make has been accused of harming monarch butterflies, honey bees, rats, and showing up in the blood of pregnant women.

Just one problem: None of that is true. (Click on any of those links to see a scientific refutation of each claim.) Seven independent experts in genetically modified crops I spoke to all confirmed that the science shows Bt crops to be safer than their alternative: noxious chemical insecticides. In Europe—where suspicions over GM crops run even deeper than in the United States—the European Food Safety Authority just rejected a French ban on Bt corn, saying "there is no specific scientific evidence, in terms of risk to human and animal health or the environment." A comprehensive report on 10 years of European Union-funded research, comprising 50 research projects, drew the same conclusions about Bt safety.

Let's face it, we're devoting enormous amounts of time and energy to minimize our exposures to toxins (think BPA, pesticides, and all the rest of the seemingly ubiquitous chemicals). But now an emerging body of research points to the disturbing possibility that such self-protective strategies might sometimes come decades, or even a century, too late.

If your great-grandmother experienced a brief toxic exposure, these studies suggest, you and your children could be at risk for reproductive illnesses and possibly other conditions. The presumed mechanism of this unfortunate inheritance is not a mutation in the DNA itself but rather changes in the biochemical on-off switches that determine whether or not specific genes get activated—a field of study known as epigenetics.

Most recently, researchers from Washington State University, led by biology professor Michael Skinner, reported last month that short-term exposure of pregnant rats to several kinds of chemicals caused ovarian disease not just in their daughters but also in two subsequent generations of females. Symptoms that paralleled those found in human polycystic ovarian disease and primary ovarian insufficiency, both of which can reduce fertility, were identified in the descendents of rats exposed to a fungicide, pesticides, dioxin, jet fuel, and a mixture of plastics, but not among descendents of controls.

Getting fatter is just as bad for the environment as reproducing, according to new research published Monday by the scientific journal BMC Public Health. The journal's "The Weight of the Nations" study determined the ecological implications of increasing "population fatness," are similar to those of population growth.

According to the study, obesity in the global population could have the same implications for food energy demands as an extra 500 million people living on the planet. Simply looking at population growth to estimate resource consumption is no longer sufficient, the researchers argue. They determined that the human race is collectively 17 million tons (15 million metric tons) overweight. As Live Science noted, that tonnage is equivalent to about 170 military aircraft carriers. The extra stress on resources stems from the greater energy that is required to move a heavier body—i.e., it's because fat people need more food.

Currently, more than one billion adults are overweight, and North America is responsible for a large portion of the problem. "Population increases in the USA will carry more weight than would be implied by numbers alone," the researchers wrote. Asia, for example, has 61 percent of the world population and only 13 percent of the extra weight. But North America has 34 percent of the excess weight but only 6 percent of the world population. That's a problem.

How fast has the climate warmed in your state? The continental United States has seen an average temperature increase of 1.3 degrees over the past century. But warming rates vary widely from region to region and state to state, according to a new report from Climate Central, a climate research group. The 10 fastest-warming states are getting hotter 60 times faster than the 10 slowest-warming states—and Rhode Island is warming the fastest of all. That's right: our smallest state has had the fastest increase in average temperatures.

Although some states had a decrease in temperatures between 1912 to 2011, temperatures in all states have risen since 1970. And, as the report's authors explain, "no matter how much or how little a given state warmed over that 100-year period, the pace of warming in all regions accelerated dramatically starting in the 1970s." That timing coincides "with the time when the effect of greenhouse gases began to overwhelm the other natural and human influences on climate at the global and continental scales," the authors noted.

Here's a map of the 10 fastest- and slowest-warming states:

Scientists believe natural climate variability and atmospheric aerosols, which block incoming solar radiation, played a role in the different paces of change.

Any of you catch the #ShellFAIL party video last week? The one where the oil company allegedly threw a rager atop the Seattle Space Needle to celebrate its new Arctic drilling ventures, only to have a model rig that served drinks malfunction and shoot crude-colored liquid all over a terrified elderly woman? What about that related website, arcticready.com, and its corporate campaign to take advantage of global warming? Play any “Angry Bergs”?

Of course, as was quickly revealed, these were actually masterpieces of viral fakery, instigated by a collaboration of Occupy, the Yes Men, and Greenpeace. Even so, the original video of the squirting rig has logged upwards of 700,000 YouTube viewers—all of whom are likely to now know a little bit more about Shell's controversial plans to drill in the Arctic circle, off Alaska's north coast.

Meet Logan Price, 28, the protester and carpenter who was in on the prank—and who originally posted the video, pretending he'd obtained it by sneaking into a private event. You might be familiar with his work: Price also questioned President Obama on alleged WikiLeaks-source Bradley Manning in a video that made the internet rounds in April of 2011. According to Price, the Shell stunt was developed to protest the drilling plans from a distance after a federal judge in Anchorage granted the company a restraining order blocking Greenpeace from interfering with its operations.

Price spoke with Mother Jones about planning the hoax, training the volunteers, figuring out how to milk the stunt for maximum publicity.

If you've got a pressing need to tell psychiatrists what you think about "disruptive mood dysregulation disorder" (translation: kids with temper tantrums), "night eating syndrome" (people who, well, eat a lot at night), and "callous and unemotional specifier for conduct disorder" (cold-fish types), now's the time to do it. Friday is the deadline for public comment on the final draft of the fifth edition of the American Psychiatric Association's Diagnostic and Statistical Manual, a volume often referred to as "the bible of psychiatry."

Actually, 'bible' is an absurd term for a text that's been rewritten—and greatly expanded—multiple times since the first edition was published in 1952. That early version was a modest effort: 132 pages with about a hundred disorders. DSM-IV, published in 1994, features almost three times the number of disorders in 886 pages—longer than my copy of The Brothers Karamazov.

I suppose one could praise the APA's commitment to updating its views and incorporating new science, although much of that new science is funded by drug companies seeking to expand their product sales. The problem is that the rest of us—patients, clinicians, hospitals, insurers, etc.—tend to view these diagnoses as a true reflection of reality, and we allow them to govern major aspects of our lives and self-identities. But psychiatric diagnoses are often, at best, clumsy human framings of complex mood states that elude easy understanding and description.

The current revision is taking place amid much greater public and media attention. Academics and jounalists in recent years have detailed the influence of drug-company money on medical research and clinical practice. They have focused on what has been called disease-mongering—the effort to expand illness boundaries in ways that tend to increase industry profits. In the case of DSM-5, researchers have doumented widespread industry ties among panel members debating the diagnostic changes. Although the APA itself has tightened its conflict-of-interest policies for DSM panel members, critics say the changes have not gone far enough.

Controversies have also erupted over efforts to redefine common disorders, including depression, addiction, autism, sexual problems and a host of other conditions—often in ways that appeared to increase the numbers likely to be diagnosed, and therefore likely to be treated with medication. After public criticism, the APA has backed away from some controversial proposals, like "attenuated psychosis syndrome" for people deemed at risk of becoming psychotic, and "persistent complex bereavement-related disorder," which critics said transformed ordinary grief into a pathological condition.

Public interest in the changes has been widespread. The open comment periods for two earlier drafts of DSM-V, in 2010 and 2011, generated almost 11,000 responses altogether. The volume is expected to be published next year.

The United States ranks supreme when measured by gross domestic product (GDP)—the value of all goods and services produced in the country in one year. Per capita, we're second to the European Union. But a different national success measurement doesn't have America anywhere near the top.

The Happy Planet Index (HPI) released its third annual report this week. HPI ranked 151 countries by their ability to deliver long and content lives (determined by survey) in conjunction with a reasonable ecological footprint—that is, providing food and other necessities for the average citizen while also absorbing that citizen's ecological impact (including carbon emissions). It's that last part of the measurement that pushed the United States to its 105-of-151 rank. Americans' life expectancy is in the top 40 and our well-being is in the top 20, but an ecological footprint of 7.19 global hectares per capita placed the US only six spots from last place in that category.

This map from New Scientist visually compares countries' rankings through distortion by GDP then by HPI.

GDP is the generally accepted measurement of national success, but several alternatives have been praised for their more comprehensive calculations. Including environmental cost within HPI make for a longer-term measure of success that takes into account the negative impacts of climate change and environmental destruction.

Arctic sea ice: Patrick Kelley | USGSArctic sea ice: Patrick Kelley | USGS

This week the extent of Arctic sea ice dipped below the extent for 2007, according to the National Snow and Ice Data Center (NSIDC). As you may remember, the 2007 season holds the record for lowest Arctic sea-ice extent in recorded history.

National Snow and Ice Data CenNational Snow and Ice Data Center

Walt Meier at NSIDC tells me the melt is accelerating, notably in the Bering Sea, where higher than normal winter ice hung around two to four weeks longer than average. But it's thawing fast now.


Arctic Ocean, 14 June 2012, sea ice opening at Beaufort and Laptev seas: NASA | MODIS | TerraArctic Ocean, 14 June 2012, sea ice opening at Beaufort and Laptev seas: NASA

The Beaufort Sea north of Alaska and Canada and the Laptev Sea north of Siberia are also melting quickly. "We don't normally see ice opening so fast in those areas," says Meier. "This is an indication that the ice there is pretty thin."

As you can see from the satellite mosaic of the Arctic for today, 14 June (above), the rapidly melting Laptev Sea lies at the downstream end of the mighty Lena River in Siberia. The Beaufort Sea lies at the downstream end of Canada's mightiest river, the MacKenzie River (delta not visible)—where May temperatures rose well above the 20th-century average (see last image, below).

Arctic sea ice thickness derived from the 2012 Operation IceBridge “quick-look” data products, spanning 14 March to 02 April 2012: S. Farrell and N. Kurtz, NASA Goddard Space Flight Center.Arctic sea ice thickness derived from the 2012 Operation IceBridge “between 14 March and 02 April 2012: S. Farrell and N. Kurtz, NASA Goddard Space Flight Center.Ice thickness data (above) show the Beaufort's sea ice to be thin—3 to 6 feet (1 to 2 meters). That's the signature of first-year ice. Which means it will be prone to melting completely this summer. Sorry, polar bears, bearded seals, ringed seals, and walruses.


Global temperature anomalies, May 2012: NOAAGlobal temperature anomalies, May 2012: NOAA

Overlay the current sea ice melt map onto this map of May 2012 temperature anomalies. You can see how warm it was in the Beaufort Sea (upper left). The Laptev Sea / Lena River region is not visible in this view.

To put things in a bigger perspective, the global temperature average in May 2012 was the second warmest in history. Records date back to 1880.

May 2012 also marks the 36th consecutive May and the 327th consecutive month—that's more than 27 years—with a global temperature above the 20th century average, reports NOAA's Environmental Visualization Laboratory.