Scientists Explain Why Even the “Biggest Losers” Regain Lost Weight


It’s very hard to lose weight, but it might be even harder to keep it off. Researchers studying contestants who appeared on The Biggest Loser say our bodies make it nearly impossible to maintain extreme weight loss, The New York Times reports. They published their findings today in the journal Obesity.

“Just eat less and exercise more.” How many times have we heard that one? And for a long time, doctors believed that willpower was the key to weight loss. And yes, eating right and exercising is a good start. But as scientists dug deeper, they found that there’s a whole lot more to it. We’re learning now that countless factors affect the composition of our bodies, from the bacteria in our guts to the chemicals in our water.

More than one-third of American adults are obese. It’s no surprise, really, that weight and shedding it have become a national obsession, one that reached new levels in the form of extreme-weight-loss reality show The Biggest Loser. Each week, viewers tuned in to watch contestants endure grueling weight-loss regimens, dangerous water and calorie restriction, and verbal abuse from trainers.

You could say that these practices “worked”: The contestants certainly lost weight. Danny Cahill, who won the show’s eighth season, dropped a record 239 pounds. Yet since the show ended, he’s regained 100 pounds. Most of his fellow contestants are in the same boat. Some are even heavier than they were when they started, despite strenuous efforts to keep the weight off. So what gives?

That’s what Kevin Hall wanted to know. Hall is a metabolism expert at the National Institutes of Health (NIH), as well as a fan of reality TV. He decided to track Biggest Loser success stories for six years after the show to see how their bodies responded to the drastic change. Cahill and other Season 8 contestants became participants in a long-term experiment, in which their weight, calorie intake, and metabolic rates were measured.

Cahill didn’t need a laboratory to see that something was wrong. “All my friends were drinking beer and not gaining massive amounts of weight,” he told The New York Times. “The moment I started drinking beer, there goes another 20 pounds. I said, ‘This is not right. Something is wrong with my body.’”

The data agreed. Analysis of the contestants’ information revealed that their metabolisms were completely out of whack. At 295 pounds, Cahill’s body burned 800 fewer calories a day than another man his size. In other words, he’d have to eat even less than someone else to stay the same weight. His body was working hard to regain lost pounds. The same was true for his fellow contestants.

Normal, small-scale weight loss typically causes some metabolic changes. But the contestants’ metabolisms continued to slow even after they’d lost the weight. As time went on, to keep the same amount of weight off, they’d have to eat less and less.

“It is frightening and amazing,” Hall told the Times. “I am just blown away.”

Diabetes researcher Michael Schwartz was not a part of the study, but he found the results disturbing. “The key point is that you can be on TV, you can lose enormous amounts of weight, you can go on for six years, but you can’t get away from a basic biological reality,” he said. "As long as you are below your initial weight, your body is going to try to get you back.”

Obesity prevention expert David Ludwig, also not involved in the study, was equally concerned. “[These contestants are] a subset of the most successful [dieters],” he told the Times. “If they don’t show a return to normal in metabolism, what hope is there for the rest of us?”

He added, “That shouldn’t be interpreted to mean we are doomed to battle our biology or remain fat. It means we need to explore other approaches.”

[h/t New York Times]

New Patient Test Could Suggest Whether Therapy or Meds Will Work Better for Anxiety

Like many psychological disorders, there's no one-size-fits-all treatment for patients with anxiety. Some might benefit from taking antidepressants, which boost mood-affecting brain chemicals called neurotransmitters. Others might respond better to therapy, and particularly a form called cognitive behavioral therapy, or CBT.

Figuring out which form of treatment works best often requires months of trial and error. But experts may have developed a quick clinical test to expedite this process, suggests a new study published in the journal Neuropsychopharmacology.

Researchers at the University of Illinois at Chicago have noted that patients with higher levels of anxiety exhibit more electrical activity in their brains when they make a mistake. They call this phenomenon error-related negativity, or ERN, and measure it using electroencephalography (EEG), a test that records the brain's electric signals.

“People with anxiety disorders tend to show an exaggerated neural response to their own mistakes,” the paper’s lead author, UIC psychiatrist Stephanie Gorka, said in a news release. “This is a biological internal alarm that tells you that you've made a mistake and that you should modify your behavior to prevent making the same mistake again. It is useful in helping people adapt, but for those with anxiety, this alarm is much, much louder.”

Gorka and her colleagues wanted to know whether individual differences in ERN could predict treatment outcomes, so they recruited 60 adult volunteers with various types of anxiety disorders. Also involved was a control group of 26 participants with no history of psychological disorders.

Psychiatrists gauged subjects’ baseline ERN levels by having them wear an EEG cap while performing tricky computer tasks. Ultimately, they all made mistakes thanks to the game's challenging nature. Then, randomized subjects with anxiety disorders were instructed to take an SSRI antidepressant every day for three months, or receive weekly cognitive behavioral therapy for the same duration. (Cognitive behavioral therapy is a type of evidence-based talk therapy that forces patients to challenge maladaptive thoughts and develop coping mechanisms to modify their emotions and behavior.)

After three months, the study's patients took the same computer test while wearing EEG caps. Researchers found that those who'd exhibited higher ERN levels at the study's beginning had reduced anxiety levels if they'd been treated with CBT compared to those treated with medication. This might be because the structured form of therapy is all about changing behavior: Those with enhanced ERN might be more receptive to CBT than other patients, as they're already preoccupied with the way they act.

EEG equipment sounds high-tech, but it's relatively cheap and easy to access. Thanks to its availability, UIC psychiatrists think their anxiety test could easily be used in doctors’ offices to measure ERN before determining a course of treatment.

A Pitless Avocado Wants to Keep You Safe From the Dreaded 'Avocado Hand'

The humble avocado is a deceptively dangerous fruit. Some emergency room doctors have recently reported an uptick in a certain kind of injury—“avocado hand,” a knife injury caused by clumsily trying to get the pit out of an avocado with a knife. There are ways to safely pit an avocado (including the ones likely taught in your local knife skills class, or simply using a spoon), but there’s also another option. You could just buy one that doesn’t have a pit at all, as The Telegraph reports.

British retailer Marks & Spencer has started selling cocktail avocados, a skinny, almost zucchini-like type of avocado that doesn’t have a seed inside. Grown in Spain, they’re hard to find in stores (Marks & Spencer seems to be the only place in the UK to have them), and are only available during the month of December.

The avocados aren’t genetically modified, according to The Independent. They grow naturally from an unpollinated avocado blossom, and their growth is stunted by the lack of seed. Though you may not be able to find them in your local grocery, these “avocaditos” can grow wherever regular-sized Fuerte avocados grow, including Mexico and California, and some specialty producers already sell them in the U.S. Despite the elongated shape, they taste pretty much like any other avocado. But you don’t really need a knife to eat them, since the skin is edible, too.

If you insist on taking your life in your hand and pitting your own full-sized avocado, click here to let us guide you through the process. No one wants to go to the ER over a salad topping, no matter how delicious. Safety first!

[h/t The Telegraph]


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