You are probably eating many more calories than you think because you aren’t looking at serving sizes.

In the chapter introduction, we used as an example of how easy it was to overeat by pouring too much cereal into a big bowl. When you calculated how many calories are in the cereal you may have been surprised because the label on the cereal box said 120 calories. But that 120 calories is per serving. How much cereal you actually ate is called your portion.

A key to practicing perfect portions is to be aware of the difference between serving sizes and portion sizes. The serving size is a standard measure selected by manufacturers for figuring out how many calories and other nutrients you are eating. Your portion size is how much food you actually put on your plate.

In the cereal example the serving size is ¾ cup, which has 120 calories. In reality you ate 2 cups of cereal for 300 calories. I don’t know if anyone has ever served themselves ¾ cup of cereal without really trying to because ¾ cup of cereal looks really small in a big bowl.

When you eat something out of a package, look at the serving size and figure out how many calories you’ll really be eating. If it turns out you’ll be eating too many calories for your calorie budget, then move to another food. Or you need to accept the smaller portion sizes.

A trick manufacturers often play is to make serving sizes smaller than you typically eat. You look at the nutrition label and see a calorie per serving number that looks reasonable and then what do you do? You eat the whole package of course! Remember the idea of unit bias; that we tend to see the whole package as what we should eat. The end result is you eat a lot more calories than you think. Don’t fall for this trick.

We have become very used to large portion sizes in American culture. The ¾ cup serving size for cereal is really the right amount. It’s the larger amount of cereal you normally eat that isn’t right. And remember from the threats we learned that you don’t need to eat larger portions you’ll still feel satisfied from the smaller portion sizes. You just need to make sure you use the right portion sizes to begin with.

How do you practice perfect portions when eating from packages? Here are a few steps to consider:

1.      Decide how many calories you have in your calorie budget to spend on eating this food. You can decide not to stick to your budget, but you should at least make a conscious decision when you ignore it. Keep a background ticker going in your brain for estimating how many calories you are eating. You can use of one of the web calorie counting services to help you get a more accurate calorie count.

2.      Look at the number of servings on the label. Look at the size of the package compared to the number of servings. Packages often advertise themselves as single serving sizes, but really have several servings per package. You can easily make the mistake of eating a package of food and hugely underestimate the amount of calories you are eating.

3.      Multiply or divide according to how much you plan to eat. If you plan on eating the entire package, then multiply the number of calories per serving by the number of servings per package to get your calorie total. Something to keep in the back of your mind is that not all labels are accurate. Even though you are doing everything right, you may still gain weight because the labels can be wrong.

’I love using spaghetti as an example because it’s stunning how many calories you eat when you eat as much spaghetti as you really want.

My box of spaghetti says there are 8 servings in the box. Each serving is 2 ounces and has 190 calories.

Let’s say I’ve already eaten about 500 calories for breakfast, 900 calories for lunch, and 300 calories in snacks, which leaves me about 1000 calories for dinner. I plan to spend about 500 calories on spaghetti. My remaining calories will be spent on chocolate, vegetables, cheese and some other dishes.

I don’t know my calorie counts exactly. I just keep a mental ticker in the back of my mind that tracks about how many calories I am eating. If I start gaining weight within a spin of The Designer Way, I’ll suspect I am not counting very well and I’ll try harder to be more accurate in my future estimates and portion sizes.

For the purposes of this example, I first take as much spaghetti as I would normally serve myself without considering the serving size. It turns out that this amounts to about 5 servings of spaghetti for a total of about 1000 calories. That’s 500 calories above my target!

Now I want to figure out how much spaghetti I should eat. First I need to know how much is two ounces of spaghetti. I have no idea, so I weigh it out on a scale. Two ounces of spaghetti is about a ½ inch circle. That’s not much. I only need about 2½ servings, not the 5 servings I would have dished out for myself. So considering serving sizes when eating really works. I prevented myself from eating 500 extra calories in just this one meal.

Imagine how many calories you’ll save yourself from over a whole lifetime?

Using Servings of Food Groups Instead of Calories

The Portion Teller, by Lisa Young, recommends against using calories to keep track of how much you can eat. Instead, she recommends eating a certain number of servings of vegetables; fruits; grains, and starchy vegetables; dairy; fats; fish, poultry, meat, and meat alternatives; treats and sweets.

So instead of a calorie budget you would have a serving budget for each food group. Let’s say your budget is 3 servings of vegetables where each serving is ½ cup. Instead of calorie ticker counting in the back of your mind you keep a servings ticker for each food group.

The reason for this approach is a good one: it helps you select a good mix of food groups in your diet and you never have to worry about calorie counting.

Personally, I eat a variety of foods so I am never worried about getting a wide enough mix of foods in my diet. And I don’t recommend what you should eat, so I couldn’t possibly recommend how many servings of each food group you should have.

Yet the servings approach is very sensible. I thought you should know about it, so you can decide if it would work better for you than the calorie approach.