Portion Distortion

Research: Recent studies show why we overeat—and offer practical clues on controlling the size of our meals, snacks and drinks.

Over the past few decades, portion sizes of everything from pizza to bagels have swelled by an average of two to five times in America (Young 2006).

“Unfortunately, waistlines have followed suit,” says Lisa R. Young, PhD, RD, adjunct nutrition professor at New York University and author of The Portion Teller Plan (Three Rivers 2006). When researchers at the University of North Carolina analyzed data from food surveys conducted in the 1970s, 1980s, 1990s and the past decade, they concluded that the average daily energy intake of a U.S. citizen increased from 1,803 kilocalories (kcal) in 1977–78 to 2,374 kcal in 2003-06 (Duffey et al. 2011)—a rise of nearly 32%, and more than enough to contribute to our expanding collective girths.

For the most part, Young says, large quantities of cheap food have distorted our perceptions of what proper portions are supposed to look like. “We also view a heaping serving of food as a bargain,” she adds. The overload is happening everywhere—in fast-food restaurants, fine-dining establishments, coffee shops and even cherished cookbooks. In examining 18 recipes published in every edition of the iconic Joy of Cooking since it first appeared in 1936, Cornell University scientists found that average calories per serving haved jumped 63% in the past 70 years (Wansink & Payne 2009). Changes in serving sizes were determined to be a leading factor behind the increases.

Thankfully, there are strategies you and your clients can use to reclaim control of food portions. Whether you are ditching oversized dinnerware or being more mindful of what you are shoveling in, these tips can help prevent portions and waistlines from swelling.

See Red
Want to curtail calorie intake? Try serving dinner on a red plate. A 2012 study published in the journal Appetite, discovered that people consumed less when food was placed on a red plate rather than a blue or white one, and they drank smaller amounts of sweetened beverages from a red-labeled cup than they did from a blue-labeled one (Genschow, Reutner & Wänke 2012). Of note, no differences in hunger levels were found among the volunteers, even when they ate less, and the color red did not reduce the overall appeal of the food or drinks. The study authors believe that because we have learned to associate red with danger and a warning to stop, it can act as a cue for consumption control. Adorning the dining area with red placemats and napkins may be another way to keep food intake in check.

Downsize
Research proves that downsizing plates, bowls and drink glasses can play a big role in portion control. A 2012 Journal of Nutrition Education and Behavior study found that when participants were given a large-sized bowl, they served themselves 77% more pasta than when they were given a smaller bowl (Van Kleef, Shimizu & Wansink 2012). In a separate study, nutrition experts served themselves 31% more ice cream when given a 34-ounce bowl than when armed with a 17-ounce one (Wansink, van Ittersum & Painter 2006). Further, their servings increased by an additional 14.5% when they were using a larger serving spoon.

Because we seem to eat with our eyes rather than our stomachs and tend to eat much of what we serve ourselves, Young says, serving meals and snacks on smaller plates can trick us into thinking we’ve eaten more. “Try serving main courses on salad-sized plates and your salads on main-dish plates,” adds Young. The Portion Plate (www.theportionplate.com) can help you visualize proper serving sizes for meats, grains, vegetables and fruits.

Size It Up
You can’t scale back your portions until you come to grips with how much you’re really eating. Flip food packages over, read nutrition information and pay close attention to how serving sizes are defined. Case in point: A brand of granola may look rather harmless at 130 calories per serving, but upon closer inspection this is just a quarter cup, less than almost anybody would eat in one sitting. So if you’re more likely to pour a half-cup or more into your bowl, it’s vital to adjust the calories appropriately and make sure you cut back elsewhere during the day. The same goes for items like frozen meals and desserts, bottled drinks and packaged snack foods.

Rise and Dine
A recent University of Missouri study demonstrates that eating breakfast can help control appetite and regulate food intake throughout the day (Leidy et al. 2011). For 3 weeks, subjects either skipped breakfast or consumed a 500-calorie meal. Consuming breakfast led to increased fullness and reductions in hunger throughout the morning, an outcome that could assist with portion control later in the day. Further, brain scans before lunch showed that activation of regions controlling food motivation and reward was lower when subjects consumed breakfast. A high-protein breakfast was particularly effective at quelling hunger, likely by helping to slow digestion. Healthy protein options for breakfast include hard-boiled eggs, plain Greek yogurt, nuts and low-fat cottage cheese.

Scale Back
Most people can’t grasp what 4 ounces of chicken breast or 1 ounce of cheese looks like—yet these portions are considered appropriate for a calorie-controlled diet. “Adding a digital food scale to the kitchen can help people understand what real portion sizes look like,” notes Young. “It may come as a shock to learn that your typical steak serving is 8 ounces or more, a lot more than what most people should eat.” She adds that using measuring cups for items like cereal can also help keep portions in line with what is stated on product nutrition labels.

Stave Off Snack Attacks
A recent study by scientists at Yale University showed that falling glucose levels can trigger a reward region in the brain that leads to heightened cravings for belly-busting, high-calorie fare such as cakes, pizza and ice cream (Page et al. 2011). In overweight people, the effect may be even more pronounced. The brain uses glucose as its primary fuel, so when glucose levels drop, it tells you to seek out food—portion control be damned. A grumbling stomach can also chip away at willpower. Take back control by making sure you eat something every few hours; include healthy snacks such as yogurt with berries; hummus and raw veggies; or whole-grain crackers with 1 tablespoon of almond butter.

Pay Attention
Eat your meals and snacks in the kitchen or dining room, not on the couch in front of the television. A review of studies published in the American Journal of Preventive Medicine found that TV viewing was strongly associated with higher consumption of calorie-dense drinks and foods and lower consumption of fruit and vegetables in both adults and children (Pearson & Biddle 2011).

“Eating in front of the television takes your attention away from the food you are consuming because [the TV] acts as a distraction,” says Natalie Pearson, PhD, study co-author and research assistant at the school of sport, exercise and health sciences at Loughborough University, England. “This causes a lack of awareness of how much you are actually eating—[which] may lead to overconsumption.” Pearson also notes that the telly inundates you with advertisements for unhealthy foods, potentially influencing what you desire and consume.

In a separate study, at the University of Bristol, England, people who ate lunch while playing a computer game felt less full by the end than those who noshed undistracted, and gamers consumed about double the number of calories 30 minutes after the meal compared with the other group (Oldham-Cooper et al. 2011). If you eat while distracted, you’ll likely remember less about the food you consumed, which can leave you feeling hungrier later on.

The takeaway is simple: When you are eating, it’s important to focus on the food, not on your email inbox or your favorite sitcom.



Chew on This
In today’s fast-paced world, many of us wolf down our food. Well, it’s time to eat at a snail’s pace. A 2011 American Journal of Clinical Nutrition investigation discovered that subjects consumed 12% fewer calories when they chewed each bite 40 times than when they chewed just 15 times (Li et al. 2011). More chewing resulted in an increased release of hunger-quashing gut hormones, such as cholecystokinin, and lower levels of ghrelin, a hormone that stokes appetite.

Additional chewing also slows down the rate at which you take in food, which New Zealand scientists found can keep weight down (Leong et al. 2011).

Eating slowly and savoring food may also explain, in part, why rates of obesity are lower in France than in North America. A 2003 study reported that average American McDonald’s® customers spent 35% less time at the table than their French counterparts (Rozin et al. 2003). Scarfers, beware: Pacing yourself gives the gut and brain enough time to register satiety signals. Make it a goal at every meal to put down utensils after each bite and chew thoroughly. Do not grab the fork again until your mouth is completely empty. Chewing food thoroughly also leads to better digestion.

Start Right
The right appetizer can keep calorie intake within reason. A 2012 study by researchers at Pennsylvania State University showed that people who ate a 100-calorie salad 20 minutes before digging into a pasta meal reduced their total caloric intake for the meal by 11% (Roe, Meengs & Rolls 2012). The same laboratory found that eating a raw apple 15 minutes before a test meal cut caloric intake by 15% (Flood-Obbagy & Rolls 2009). Preceding meals with low-calorie, fiber-rich items like vegetables and fruits can boost satiety, making it less likely you’ll dole out copious amounts of spaghetti or ask for second helpings of meatloaf. But don’t expect the same benefit when you order calorie-laden appetizers like spinach artichoke dip or calamari.

Slice Away Calories
Cutting calories could be as simple as cutting up your food. A 2011 study published in Journal of the Academy of Nutrition and Dietetics found that subjects who ate whole pieces of candy while participating in a computer task consumed about 60 more calories than those who nibbled on candies that were sliced in half (Marchiori, Waroquier & Klein 2011). Both groups consumed the same total number of candy pieces—six to seven whole candies or six to seven candy halves. No substantial hunger differences were found between the groups. “Given that we tend to consume a similar number of food items, altering the size of these food items can lead to an increase or decrease in food intake,” says lead study author David Marchiori, PhD, teacher in the social sychology unit at Free University of Brussels. We tend to think of one chicken breast as an appropriate serving size regardless of whether it is 3 ounces or 6. So try slicing up items like steak, chicken and potatoes into smaller portions before putting them on serving plates.

Sleep Tight
Here’s another reason to get a good night’s sleep: An investigation by scientists at New York Obesity Research Center found that subjects fed themselves about 300 more calories when sleep-deprived than they did after sleeping normally (St-Onge et al. 2011). Why does lack of pillow time lead to the munchies? A 2012 American Journal of Clinical Nutrition study reported that subjects who slept only 4 hours showed more brain activity in response to food stimuli than those who got 9 hours of shut-eye (St-Onge et al. 2012). So a poor night’s sleep could cause the concept of portion control to go AWOL and make it more likely that you’ll give into your food desires.

Choose True Grit
Fiber-rich foods slow down digestion and minimize blood sugar fluctuations. Incorporating these foods into snacks and meals will boost satiety and tame hunger, making it less likely you’ll eat Garfield-sized portions. A study in the journal Appetite found that volunteers felt fuller after consuming high-fiber bread than they did when they consumed the same number of calories from fiber-poor white bread (Keogh et al. 2011). Men should aim for 38 grams of fiber a day and women for about 25 grams, according to the Academy of Nutrition and Dietetics (AND 2012). To reach the mark, it’s important to eat plenty of fruits, vegetables, nuts, seeds and whole grains.

Keep Your Distance
At your next meal, try this suggestion from Cornell University: Keep extra food away from the dining table. Cornell scientists found that when subjects kept pasta and pudding serving-dishes off the table, obliging the subjects to serve themselves from dishes on the kitchen counter or on the stove, they ate an average of 20% fewer calories (Payne et al. 2010). The study authors surmised it was a case of “out of sight, out of mind.” The less effort it is to eat, the easier it is to shovel in food. Try this: Dole out a portion of food onto a plate or into a bowl and then place the rest in the refrigerator. The visual cue of a clean plate will help signal that you’ve had enough to eat. “This also applies to snack food like nuts, where it’s best not to have a bagful nearby,” says Young.

Eat Your Calories
It’s okay to have a glass of orange juice with breakfast or a postworkout protein shake, but it’s important that most of your daily calories come from solid food. A study conducted by scientists at the University of Kansas Medical Center found that postmeal hunger and desire to eat were greater when subjects consumed liquid calories than when they consumed the same amount of energy from solid food (Leidy et al. 2010). The investigation found that the solid meal led to a greater drop in ghrelin, the hunger-producing hormone, than the liquid meal. “The body doesn’t respond to liquid calories in the same way it would if those calories came in the form of whole food,” explains Young. “So it’s possible that drinking too many of your calories could lead to overeating by increasing hunger.”

Be the Chef
Portions doled out at restaurants have been growing over the last several decades. When you leave the food prep to someone else, you always raise the risk of getting more calories than you bargained for. “Cooking more of your meals allows you to become better aware of appropriate portions and often leads to eating higher amounts of healthful foods,” Young says. But make sure to use measuring spoons, scales and other devices to keep sneaky excess calories out of your meals. For example, don’t just hold a bottle of oil over a skillet or salad bowl—measure out what you need.

Know the Real Deal
Ironically, the nation got more Pillsbury® Doughboy™– like only with the widening consumption of low-fat this, low-fat that. That’s because the low-fat version of an item like peanut butter may have calories on par with the higher-fat version, since ingredients like sugar often replace the fat to make the product taste better. “Low-fat items can trick you into thinking you’re eating less than you are,” says Young. A Journal of Marketing Research study found that people ate 28% more chocolate candies when they were portrayed as “low-fat” than when they were described as “regular” (Wansink & Chandon 2006). The researchers concluded that low-fat labels cause people to underestimate calorie consumption, increase what they think is an appropriate serving size and temper feelings of guilt after polishing off a box of reduced-fat treats. The upshot is that “reduced-fat” versions of products like crackers, cookies, fruit yogurt and peanut butter need the same dietary constraint as their higher-fat counterparts.

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References
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December 2012

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