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Today, 59 per cent of the Canadian population is overweight or obese, a number that has steadily climbed for almost every age group over the past 25 years. And research suggests that once you're overweight it's much easier to pack on more pounds than it is to take them off. It's not rocket science why we've become such a flabby nation -- we move too little and eat too much.

Overeating is easy to do. Food is plentiful and often served in ridiculously large portions. Since the 1960s, serving sizes of foods sold in stores and restaurants -- from chocolate bars to burgers and soft drinks -- have become much bigger. Fast-food restaurants offer king-size meal combos, muffins and bagels have doubled and tripled in size, and family-style restaurants serve pasta meals that could feed a family of four.

Bigger food can lead to bigger people. Studies show that people consume more food and more calories when given larger portions, often without realizing they're actually eating big portions. A study published in this month's issue of the Journal of the American Dietetic Association supports the notion that people perceive super-sized portions as appropriate amounts to eat -- a phenomenon called portion distortion.

Researchers at Rutgers University in New Brunswick, N.J., found that portion sizes chosen by university students were not only larger than those defined by nutrition labels, they were significantly larger than portion sizes selected by young adults two decades ago. In the study, 177 college students aged 16 to 26 were asked to serve themselves "typical portion sizes" at either breakfast, lunch or dinner. The researchers then weighed the portions and compared them to reference serving sizes given on food labels.

A "portion" size is just the amount of food you choose to eat in one sitting, whether it's from a restaurant, a package or your kitchen. A "serving" size, on the other hand, is a specific amount of food defined by Canada's Food Guide, nutrition labels, some cookbooks, and many diet plans. (In the case of the Rutgers study, serving sizes were based on what is presented on nutrition labels.) Individually packaged and ready-to-eat foods that are larger than reference portion sizes translate into bigger portions served at home. For instance, if you're used to buying a 473-millilitre bottle of orange juice with lunch (a portion that wasn't available two decades ago), you might think nothing of pouring a similar amount in your glass at home -- a portion size that's equivalent to almost four servings in a food guide. Studies also find that despite increased food intake, people presented with large portions generally don't report feeling more full, suggesting that our body's satiety signals are ignored when we eat super-sized portions.

Consuming larger portions from bigger single-serve containers can eventually show up on the scale if those extra calories aren't burned off. Recently, researchers from Pennsylvania State University gave 60 participants, on five separate days, an afternoon snack and dinner. On each of the days, the subjects where served a different sized package of potato chips (28, 42, 85, 128 or 170 grams) and then returned to the lab three hours later for dinner. On average, when participants were served the largest bag of potato chips compared against the smallest, an additional 143 calories were consumed at snack and dinner combined. That may not sound like a lot, but over time, snacking on a larger package of potato chips can make a big difference in body weight -- 14.5 pounds over one year to be exact.

Thanks to inflated portion sizes, you might be eating more than you think. And if you're struggling with your weight, assessing your portion sizes is a key to slimming down.


The best way to figure out how much you're eating is to measure your foods in a measuring cup or with measuring spoons and then compare your portions with serving sizes recommended by Canada's Food Guide. Read nutrition labels on food packages to become familiar with serving sizes of your favourite brands of cereal, crackers, snack foods, even salad dressing. You might be surprised to learn that one serving is much less than what you're used to eating.


If measuring makes you crazy, eyeball your food portions to make sure you're eating an appropriate food guide serving size. Visualize familiar objects that represent normal portion sizes. For example, three ounces (90 grams) of meat looks like the size of a deck of playing cards, one cup (250 ml) of cooked pasta is roughly the size of a tennis ball and a teaspoon of butter looks like the tip of your thumb.

Look at your plate

Is half of your dinner plate covered by a slab of meat? Is it overflowing with spaghetti and meat sauce? To control your portion size, divide your plate into four sections, or quarters. Fill one quarter with meat, chicken, fish or tofu. Fill another quarter with starchy foods such as cooked rice, pasta, potato or quinoa. The remaining half should be filled with vegetables.

The following strategies can help you pare down your portions whether you're eating at home, in a restaurant, even at the movies:

Buy small packages of food. If you shop in bulk, break jumbo-sized packages into smaller, individual-sized portions.

Ask for smaller portions when dining out. Split an entrée with a friend, or order two appetizers instead of an entrée.

Use smaller plates. Instead of filling a dinner plate, serve your meal on a luncheon-sized plate. The plate will look full and you'll end up eating less.

Add fruit and vegetables to meals. Fruits and veggies contain fibre and water; they add volume to meals and can help you feel satisfied on fewer calories.

Don't snack "from the bag." When snacking, measure out one serving of crackers, popcorn or potato chips and place it in a small bowl to prevent overeating.

Leslie Beck, a Toronto-based dietitian at the Medcan Clinic,

is on CTV's Canada AM every Wednesday. Visit her website