Health & Science
Antarctica’s hidden volcanoes
Geologists have identified 91 previously undiscovered volcanoes beneath the Antarctic ice sheet—a massive range that has the potential to trigger a catastrophic rise in global sea levels. The discovery was made by researchers from the University of Edinburgh using ice-penetrating radar. The 91 peaks lie under more than a mile of ice, and along with 47 previously identified volcanoes make up the largest volcanic region in the world. If one or more of these volcanoes erupted, co-author Robert Bingham tells The Guardian (U.K.), it could have a catastrophic effect on climate change. “Anything that causes the melting of ice, which an eruption certainly would, is likely to speed up the flow of ice into the sea,” he says. “The big question is: How active are these volcanoes?” Global warming could cause a feedback loop: Melting ice relieves downward pressure on the volcanoes, which could then become more active. Bingham notes that the most active volcanic regions in the world—among them Iceland and Alaska—lost their glacial covering after the last ice age. “It is something we will have to watch closely,” Bingham says.
The ‘fat but fit’ myth
The theory that you can be “fat but fit”— overweight or obese, yet still healthy—is flawed, a British study has concluded.
Researchers analyzed the historical health data of more than half a million people from 10 European countries. They separated them into two groups: “metabolically” healthy and unhealthy, based on markers such as blood pressure and cholesterol levels. They then divided the subjects by body mass index, classifying them as normal weight, overweight, or obese. As expected, the metabolically unhealthy contingent had the highest risk for heart disease. But the overweight or obese people who were “metabolically healthy” were still about 28 percent more likely to develop heart disease than those with a healthy body weight. “Our study shows that people with excess weight who might be classed as ‘healthy’ haven’t yet developed an unhealthy metabolic profile,” researcher Ioanna Tzoulaki tells BBC.com. “That comes later.”
The perils of the kitchen sponge
If you want to make your kitchen more hygienic, start by replacing the sponge. That’s the conclusion of a new German study, which found that kitchen sponges harbor a stunning amount of bacteria. Researchers at Furtwangen University studied 14 used sponges from family kitchens in southwestern Germany. They identified 362 different species of bacteria; one cubic inch of sponge, they found, held as many as 82 billion microbes—the same density you’d find in human stool samples. With lots of warm, wet, nutrient-rich space, sponges provide the perfect habitat for bacteria. Attempts to disinfect sponges aren’t very effective, researchers found: Microwaving and boiling water kill off some of the weakest, smelliest bacteria, but enable Moraxella osloensis, a potentially pathogenic bacterium, to flourish in their place. Study author Markus Egert recommends replacing the sponge weekly, but notes that the dangers are still relatively low for people with healthy immune systems. “You should not become hysterical and afraid of your kitchen sponge,” he tells The New York Times. “But if you’re already ill or have ill people at home, you should be more careful.”
Health scare of the week
Tattoos reduce sweating
Covering large areas of the body with tattoos may restrict how people sweat, reports The New York Times. Tattoos are formed by injecting dye into the skin’s dermal layer, which holds sweat glands. To investigate the effects of tattoos on sweat production, a team at Alma College in Michigan found 10 healthy young men who had a tattoo on one side of their torsos and untattooed skin on the other side. The researchers placed small chemical patches that initiate sweating on both areas, then measured the quantity and makeup of the resulting perspiration. The tattooed skin, they found, produced nearly half as much sweat as the unmarked skin—and nearly twice as much salt. The age of the tattoo had no bearing on the results. Maurie Luetkemeier, the study leader, says it is “unlikely” tattoos can impede sweating enough to cause exercising people or athletes to overheat: When sweat glands are rendered nonfunctional by other means— severe burns, for example—the body increases sweat levels in other areas of the body. But Luetkemeier says further research is needed into the tattoo effect. ■