Upending daily rhythm triggers fat cell growth

New research may help explain why chronic stress, sleep deprivation and other disruptions in the body’s daily rhythms are linked to obesity.

Chronic exposure to stress hormones stimulates growth of fat cells, Mary Teruel of Stanford University reported December 16 at the annual meeting of the American Society for Cell Biology. Normally, stress hormones, such as cortisol, are released during waking hours in regular bursts that follow daily, or circadian, rhythms. Those regular pulses don’t cause fat growth, Teruel and colleagues discovered. But extended periods of exposure to the hormones, caused by such things as too little sleep, break up that rhythm and lead to more fat cells.

Even though only about 10 percent of fat cells are replaced each year, the body maintains a pool of prefat cells that are poised to turn into fat. “If they all differentiated at once, you’d be drowning in fat,” Teruel said.

Previous studies have shown that a protein called PPAR-gamma controls the development of fat cells and that stress hormones turn on production of PPAR-gamma. Teruel’s team discovered that prefat cells with levels of PPAR-gamma below a certain threshold don’t transform into fat in laboratory tests. Steady hormone exposure eventually allowed the precursor cells to build up enough PPAR-gamma to cross the threshold into fat making. But in cells given the same total amount of stress hormone in short pulses, PPAR-gamma levels rose and fell.

The stress hormone works like pushing on a car’s accelerator. Steadily increasing pressure eventually puts the car over the speed limit, while pulses effectively take the foot off the gas pedal, causing periodic slowdowns that fall short of the fat-making threshold. Pulses shorter than 12 hours didn’t make extra fat, while longer pulses, such as those that may be caused by sleep deprivation, overeating or other disruptions in circadian rhythms, increased the number of precursor cells that became fat cells.

Things you should never gift anyone on Christmas

Christmas is less than two weeks away and let’s be honest, you probably haven’t even started shopping. That’s OK. What isn’t OK is waiting until the last minute and buying a bunch of lame gifts so you can cross all the names off your shopping list. Don’t be that person. Christmas gifts aren’t something you HAVE to buy. They’re an opportunity to connect and strengthen you relationship with someone. Look at it this way: If you don’t want to be around to see someone’s face when they open your gift, then it’s probably lame. But just in case you still need some guidance, here are 10 things that are totally unacceptable to give as as christmas gifts — NO MATTER WHAT.

1. TIE

The fact that the tie industry has tricked so many people into buying a tie for the man in their life on just about every major holiday is subliminal advertising at its finest. Don’t be one of those lemmings who marches into Macy’s in desperate search of the perfect-patterned tie to go with your Pop’s pinstripe suit. If you’re dead set on buying somebody a piece of cloth that hangs around their neck, consider a stylish scarf or neckerchief they’ll be stoked to wear.



It doesn’t matter if it’s an antique, or if it says “Best Friends Forever” on it, or if you crafted it out of driftwood you collected on some deserted beach. Please, do not give people picture frames for Christmas. Instead, consider a piece of unique art, framed or otherwise, or perhaps a thoughtfully curated photo book of your favorite moments together.


Wine is for dinner parties. Whiskey, scotch and rare, small-batch rums are for gifting. But mostly just scotch. That is all.


As a general rule, you probably shouldn’t do too much Christmas shopping at Bed, Bath & Beyond. Nothing says “I don’t know anything about you, so here you go” like a bag full of chemicals. Instead, consider gifting someone a relaxing massage, or, if you have the coin, some spa time.

5. MUG

Just like picture frames, the variety and customizability of mugs will make them a tempting gift for the not-so-savvy shopper. I mean, everybody drinks coffee, right? Well everybody shits too, but that doesn’t mean you’re going to find a 24-pack of Charmin Ultra Soft under the Christmas Tree, does it? Instead, get, like, a tiny bit creative and buy somebody a rad tea set or maybe a practical but stylish tumbler or thermos.


Look, you really have no idea if somebody is going to like a certain scent enough to consistently spray it on their body. Even worse, they could be allergic. And if you already know somebody likes a certain type of perfume or cologne, what’s the point of buying more? You’re sort of just helping them stock up. You might as well get them a year’s supply of toothpaste while you’re at it.


Hopefully you’ve learned by now that personal hygiene products do not make for good Christmas gifts. But just in case you haven’t, no, you do not want to buy somebody a small, battery-powered, vibrating device with which they can trim their nose hairs.


If you’re giving somebody socks and underwear, then you probably know them well enough to to know what type of socks and underwear they like, which means you shouldn’t be giving them socks and underwear. You’re better than that. Take it up a notch and get them literally anything else.


Fruit cakes were once in style. Then they were out of style. Now you might think they’re in style again because gifting one would be ironic. But you would be wrong. That would just be stupid. And even if somebody you know enjoys the hell out of fruitcakes, frankly, you should still not get them a fruitcake — unless you’re a time traveler going back to the 1960s.


Paperweights were once useful because computers didn’t exist. That was a long time ago. Today, “paperweight” is a term applied to any seemingly interesting doodad that is so useless it must be assigned a function. Hence, it becomes a paperweight. But really, it’s a piece of crap you probably bought in a gift shop somewhere, and you should not subject an innocent person to the poor tastes that plagues most of us during impulse purchases.