How to get a gut.
It creeps up on you. One day you can't seem to fasten your skirt, your pants feel snug, you notice a bulge over your seat belt.
You're not alone. The average adult American gains about a pound per year. And fat around your middle is the worst for your health, because it raises the risk of heart disease, diabetes, and possibly dementia.
Not sure where the gut came from? Here's some of the latest research on what makes us gain weight ... and waist.
Why worry about your waist? "That's where people tend to gain fat," explains Eric Rimm, associate professor in the departments of epidemiology and nutrition at the Harvard School of Public Health in Boston. And it's not just a matter of appearance.
"We look at the waist because it's a strong predictor of a number of chronic diseases like diabetes and heart disease," says Rimm. "It's especially strong among older men, because they lose muscle mass as they age, so their weight stays constant while their girth is getting larger."
Here are eight tongue-in-cheek tips that can bulk up your belly.
1 Don't bother getting up.
You sit in the car, at the office, at your home computer, and in front of the TV. Why move when you can work, e-mail, shop, and talk on the phone without so much as standing up (except to walk to the bathroom, kitchen, or car)? Moving your limbs is becoming obsolete.
"Throughout evolution, we needed muscle and bone because we spent a lot of time walking around," says Janet Rubin, professor of endocrinology and metabolism at the University of North Carolina School of Medicine in Chapel Hill. "Now we don't do much of that, so we're defaulting toward having more fat instead of muscle and bone."
Rubin is one of a cadre of researchers who are studying whether inactivity may drive the body to make new fat cells. "Any mesenchymal stem cell can become a bone cell, a muscle cell, or a fat cell," she explains. "The question is whether the mechanical signals from exercise can alter the decision of cells to end up as fat."
When researchers put mice on a barely vibrating platform for 15 minutes a day to simulate very-low-level muscle movement, the mice committed fewer stem cells to becoming fat cells. (1)
"We know you can control the size of fat cells with calories," says Rubin. "The question is whether you can control the number of fat cells through exercise."
Of course, even if stem cells have little to do with your gut, it's clear that burning calories is critical.
For example, researchers assigned 168 overweight postmenopausal women to either aerobic exercise--most walked or rode stationary bicycles--for at least five days a week for 45 minutes a day, or to stretch at least once a week for at least 45 minutes. (2)
After one year, those who came closest to following that advice--they exercised for 195 minutes a week, which is roughly equivalent to 40 minutes a day, five days a week--lost 7 percent of their intra-abdominal fat. Those who exercised five days a week for about 30 minutes a day lost 6 percent, and those who exercised five days a week for less than 30 minutes a day lost 3 percent.
On average, the women in the stretch group lost no weight. But those who were the least overweight when the study began ended up with 7 percent more intra-abdominal fat.
"Even if you don't see dramatic weight loss, exercise reduces overall body fat and hidden intra-abdominal fat, the most dangerous type," says study author Ann McTiernan of the Fred Hutchinson Cancer Research Center in Seattle.
It's not just walking and running that matters. Scientists assigned more than 160 overweight and obese women aged 25 to 44 to do strength training twice a week or to receive a brochure recommending aerobic exercise. (3) After two years, the strength trainers had a 4 percent drop in total body fat, but a 7 percent rise in belly fat. Far worse, the brochure group lost virtually no total body fat, and had a 21 percent rise in belly fat.
"Most Americans gain one to two pounds on average every year, and that adds up to dangerous levels over a lifetime," says McTiernan. "Regular, moderate-intensity exercise can help keep the weight from creeping on, which can translate to a lower risk of diabetes, cardiovascular disease, or cancer in the long run."
2 Keep eating as much as you ate in your 20s.
You always have chips with your sandwich, always clean your plate when you go out for Italian, always order egg rolls when you have Chinese, always get a pastry with your coffee. It's never been a problem, so why change now?
Here's why: "As you get older, calorie requirements go down," says Susan Roberts, director of the Energy Metabolism Laboratory at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University in Boston.
You need fewer calories as you age because your metabolic rate is falling, because you're burning fewer calories to process the food you eat, and because you're making fewer spontaneous movements. (4)
"You use fewer calories per year, even if you keep up the same level of activity," explains Roberts, who served on the National Academy of Sciences' Institute of Medicine panel that estimated calorie needs.
And who's as active as they were in their 20s anyway? How many people spend as much time running, biking, or playing tennis or soccer as they did back then?
Even if you put in the same hours exercising, your ability to transport and use oxygen drops with age, so it feels harder to get the same workout, says Roberts.
"Someone who's 70 years old is just not capable of the same level of exertion as a 20 year old."
Many people realize that they have to cut calories as they age, but they don't realize how many. "Women going through menopause know that their calorie needs do go down, but the magnitude of how much is a big shock," says Roberts.
For men, the drop in calorie needs is even greater.
"At the age of 20, a guy has lots of room for discretionary foods like cake, brownies, chips, whatever," says Roberts. "But by the time he gets to 60, there's no room for any of that stuff. It requires a profound shift in what he eats."
Men are willing to make small cuts, she adds, "but they don't realize that they may need to eat 1,000 less calories at 60 versus at 20."
3 Bump up your calories per bite.
Chocolate. Butter. Cream. Brownies. Who says you can't have your cake and eat it too?
Foods like cookies, cakes, pies, doughnuts, croissants, chips, and pretzels are calorie-dense. That means they pack a lot of calories into each bite, so more calories reach your still-room-for-more fat depots.
"We've done a series of short-term studies where we reduced calorie density by one-third and people didn't even notice," explains Barbara Rolls, professor of nutritional sciences at Pennsylvania State University in University Park.
When people eat the same number of spoonfuls, they don't notice if each one has fewer calories. "They eat a consistent weight or volume of food. It's a pretty fundamental response."
In longer-term studies, cutting calorie density helps people lose weight. For example, Rolls and her colleagues randomly assigned nearly 100 obese women to either eat less fat or to eat less fat and increase water-rich (non-calorie-dense) foods, especially fruits and vegetables. (5)
"After six months, the group that combined reducing fat and eating more fruits and vegetables lost five more pounds," Rolls notes. The women also reported feeling less hungry.
In another study, people who cut their calorie density the most lost more weight (13 pounds) over six months than people who cut their calorie density the least (they lost 5 pounds). (6)
On the flip side, calorie-dense foods seem to leave a lasting impression on your bathroom scale. In a recent study of 186 women, those who reported eating more calorie-dense foods--like baked desserts, refined grains, and fried potatoes--gained 14 pounds over six years, while those who ate foods with a lower calorie density gained only 5 1/2 pounds. (7)
How do you lower calorie density? "The biggest influence is the water content of foods," explains Rolls. "So you can eat more fruits and vegetables, broth-like soups, lean protein foods like chicken and fish, and whole grains, which absorb water." Cutting fat also helps.
"We're not talking about a very-low-fat diet," says Rolls. "But you can reduce unhealthy fats you don't need. Some people would prefer foods with less fat. I know I would when I'm eating out, and foods are sometimes swimming in oil."
There's a bonus for cutting out extra fat, adds Rolls. "If you take some fat out, you can get bigger portions for the same number of calories."
4 Drink your calories.
Thirsty? Have a glass of juice with breakfast. Some apple cider would go well with that sandwich. And wouldn't a nice White Chocolate Mocha warm you up on your way to work? Only one problem.
"After we eat, our hunger goes down, but it goes down further and stays at a lower level after we eat a solid than after we drink a liquid," explains Wayne Campbell, professor of foods and nutrition at Purdue University in West Lafayette, Indiana.
Whether you eat or drink your calories also affects your next meal. A review of 42 studies found that when people eat 100 calories of solid food, on average they consume about 65 fewer calories at their next meal. When they eat 100 calories of semisolid food, they eat 21 fewer calories at their next meal. But when they drink 100 calories of liquid, they don't cut back at all later. (8)
"If you've just had calories in a solid, you're likely to eat less at the next meal than if you've just had calories in a beverage," says Campbell.
In a small study, Campbell found that people gained one pound when told to drink 450 extra calories' worth of soda every day for two weeks, but that they gained no weight when told to eat 450 extra calories' worth of jelly beans. (9) He has a larger, eight-week study under way to see if the effect lasts longer.
What might make liquid calories different? "The data suggest that some of the hormones that control appetite respond differently when calories hit you as liquid versus solid," says Campbell.
For example, Campbell tested SlimFast bars versus Slim-Fast shakes on ghrelin, a hormone that makes you want to eat. (10) "We found that ghrelin goes down and stays down longer after the solid."
The solution is obvious: switch to calorie-free beverages like water, coffee, or tea. "Water is not only quite capable of hydrating you, but you're less likely to overconsume it because your thirst response gets turned off," Campbell explains. "With the sweetness or flavors in other drinks, that might not happen."
Diet sodas may create other problems. "Some studies suggest that artificial sweeteners may mess up the body's internal sensing of when it's getting calories, which could lead to overconsumption of calories," notes Campbell.
And sodas and juices may cause more trouble than milk or smoothies. "The weakened compensation for beverages is most pronounced for clear beverages," says Campbell, "though I'm not saying you should head out for a milk shake."
Soup is an anomaly because people do compensate for its calories. In fact, soup has a low calorie density, so it helps people feel satisfied with fewer calories.
What's special about soup? It's possible that the difference starts in your head. "People don't compensate for the calories in soup if researchers make it appear to be a beverage instead of a meal," says Campbell. "What you expect you're consuming may affect how your body responds."
The bottom line: don't ignore the calories in your glass. "Those calories count," says Campbell. "If you have a choice between a glass of apple juice and an apple, pick the apple."
5 Eat out more often.
Why dine in when you can go out or get take-out? It's less work, and it's usually less boring. It's also a great way to get a gut.
"The calories in restaurant foods are obscene," says Tufts's Susan Roberts. "I ate at a steakhouse last night because it was my husband's birthday, and the smallest steak on the menu was 10 ounces."
And few people go out only on birthdays. Foods eaten away from home jumped from 18 percent of calories in the late 1970s to 34 percent of calories in 1995. (11) That's roughly the same period during which obesity rates took off.
In one of Roberts's studies, people who ate out at least 13 times a month consumed nearly 32 percent more calories per day than people who ate out no more than about four times a month. (12) That's partly because serving sizes are enormous.
At many restaurants, you can spend 1,000 calories or more on popular entrees like lasagna, spaghetti and meatballs, a personal pizza, a burrito, General Tso's chicken, Kung Pao chicken, or lo mein. An entire appetizer like a platter of stuffed potato skins or buffalo wings or a cheese quesadilla can plaster another 1,000 calories on your frame. And you can wrap up your meal with a 1,000-calorie dessert like cheesecake, tiramisu, or a fudge brownie sundae.
"Huge portions don't just matter when you eat out," notes Roberts. "They warp your expectations of what's normal at other times. After you eat an eight-ounce hamburger at a restaurant, a four-ounce hamburger when you eat at home seems puny."
And restaurants offer more variety, which has boosted calorie intake by 25 percent in short-term studies. Even a minor change in variety--like offering pasta in more than one shape--makes people eat more. (13)
Of course, giving up restaurants completely is unnecessary. "It's part of the fabric of many people's lives," says Roberts. "But eating out less frequently is one of the easiest things you can do" to keep your gut from growing.
6 Look for trans fats.
It's getting harder to find trans fat these days, but you can still get it buried inside some pie crusts, pastries, microwave popcorns, frozen pizzas, and biscuits. You can also get it in restaurant foods, unless you're eating out in New York City, Philadelphia, or a few other cities where trans fats are virtually banned.
What does trans have to do with your waist?
The first clue came in 2003, in a study of more than 16,000 men. Harvard researchers found that those who ate more trans fat were more likely to gain waist circumference over eight years. (14)
Four years later, researchers at Wake Forest University School of Medicine in Winston-Salem, North Carolina, reported on a study of 42 male African green monkeys. (15) For six years, half the monkeys were fed diets rich in trans fats and the other half were fed diets high in monounsaturated fats. The researchers tried to give the monkeys only enough calories to keep their weight constant, but the transfed-monkeys' weight jumped 7 percent, while the mono-fed-monkeys' weight rose only 2 percent.
What's more, the trans-fed monkeys had higher post-meal blood insulin levels, suggesting that they had become insulin-resistant, which could raise the risk of diabetes and heart disease.
"Trans fat could be interfering with the ability to send signals through cell membranes," says Harvard School of Public Health researcher Eric Rimm. "And that could interrupt normal fat storage and fat burning."
7 Surround yourself with food.
When someone offers you something yummy, why not oblige? You don't want to be rude. And even if it's not a person, but, say, the counter at Starbucks that's making the offer, why not go for it? Turns out you're hungrier than you realized.
Sound familiar? If so, you may be what researchers call "disinhibited."
"These are people who take food opportunities," says Tufts University's Susan Roberts.
"It's the person who takes a slice of birthday cake even though it's 2 p.m. and they're still full from lunch."
Disinhibition isn't just a matter of willpower.
"It's the person who goes into Dunkin' Donuts to buy coffee and looks at the doughnuts and 30 seconds later they're hungry," says Roberts. "So whether they buy the doughnut or not, they probably eat more overall, because the doughnuts have stimulated their hunger."
Having willpower is closer to what scientists call restraint. "A restrained eater will think about which salad dressing to buy and will eat salad for lunch five days a week because it has 400 calories versus a burrito, which has 700," says Roberts. "Being restrained helps a small amount, but not as much as if you're not disinhibited in the first place."
In a study of over 600 postmenopausal women, disinhibition was a stronger predictor of weight gain than restraint or hunger. (16) "If you're extremely disinhibited, you gain something like 40 pounds between the ages of 30 and 55," says Roberts.
Restaurant food isn't only to blame. Surrounding yourself with food at home or at work is also a recipe for gut expansion. For example, secretaries ate more candy if a bowl sat on their desk rather than six feet away, and they ate more if the bowl was clear than they did if it was opaque. (17)
The solution: keep your distance. "For example, don't go into Dunkin' Donuts and try to tough it out with the doughnuts if they tempt you," says Roberts. "Just don't go in."
8 Get less sleep.
So what if you stay up late again? You'll just drag yourself out of bed and double the caffeine tomorrow morning. No one gets a good night's sleep these days anyway.
In fact, roughly one out of three men and women aged 30 to 64 reported sleeping less than six hours a night in 2004, up from one out of four in 1985. (18) (Experts recommend at least seven hours of sleep a night.) What on earth does sleep have to do with your belly?
"Large epidemiological studies have found a relationship between short sleep duration and obesity," explains James Gangwisch, an assistant professor in the division of cognitive neuroscience at the Columbia University College of Physicians and Surgeons in New York.
For example, in a study that tracked more than 68,000 nurses for 16 years, the odds of gaining at least 33 pounds were 32 percent higher among those who slept no more than five hours a night than among those who slept at least seven hours. (19)
No one could easily explain the link, says Gangwisch, until researchers at the University of Chicago kept healthy young men from sleeping more than four hours a night for two nights in a row. (20)
"When they were deprived of sleep, their appetites went way up," says Gangwisch. "And they craved sweets and carbs in particular."
The men's preferences for foods like bread, pasta, potatoes, cakes, cookies, and candy jumped 33 percent. Meanwhile, ghrelin (a hormone that makes you hungry) rose 28 percent and leptin (a hormone that curbs appetite) dropped 18 percent.
What's more, says Gangwisch, "we knew from earlier studies that sleep deprivation leads to an increase in insulin resistance." That may also explain why people who sleep less have a higher risk of diabetes. (21)
Gangwisch suggests that sleep might have gotten linked to eating during human evolution, when summer meant longer days--and less sleep--than winter for people who lived away from the equator.
"In summer, sugars and carbohydrates from fruits and other plant foods were available," he speculates. So it was a good time to stock up on fuel. "Short sleep duration during the summer may have been a signal to the body that now is the time to build up fat reserves to endure the winter."
And storing fat deep in the belly might have had an advantage. "Intra-abdominal fat is more adaptive to protect our internal organs in winter," says Gangwisch.
But the genes that helped us survive those winters or adapt to famine are not helping now. "Our ancestors would have burned up that fat over the winter," says Gangwisch. "But we just keep piling it on."
Each sandwich has 270 calories, but the larger one has lower calorie density, thanks to whole wheat bread, reduced-calorie mayo, and grapes. Odds are, the smaller sandwich will leave you hungry for more.
Source: The Volumetrics Eating Plan, by Barbara Rollss (Harper, 2007)
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(2) JAMA 289: 323, 2003.
(3) Am. J. Clin. Nutr. 86: 566, 2007.
(4) Dietary Reference intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (books.nap.edu/openbook .php?isbn-0309085373&page=107).
(5) Am. J. Clin. Nutr. 85: 1465, 2007.
(6) Am. J. Clin. Nutr. 85: 1212, 2007.
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(18) MMWR 54: 933, 2005.
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(20) Ann. Intern. Med. 141: 846, 2004.
(21) Sleep Med. Rev. 11: 163, 2007.
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|Title Annotation:||weight gain and waist bulge|
|Publication:||Nutrition Action Healthletter|
|Article Type:||Cover story|
|Date:||Dec 1, 2008|
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