This is an excerpt from Fitness for Life Canada With Web Resources by Guy Le Masurier,Charles B. Corbin,Kellie Baker & John Byl.
Table 14.8 shows how you can use the FIT formula as a guideline for nutritional fitness. Too often, teens in particular violate the FIT formula. For example, some skip breakfast or lunch, which often leads them to overeat later in the day. Skipping meals can make you feel tired during the day and can make it difficult to concentrate, thus contributing to poor school performance. If you play on a sport team, skipping meals can negatively affect your performance.
In addition, many people don't know how many calories they should consume each day. This number, however, is easy to determine (see this chapter's self-assessment). As you learned earlier, a person's nutrient needs vary according to age, sex, height, weight, and daily physical activity. Young people who are going through puberty or are still growing have special nutritional needs; specifically, they need to eat foods high in minerals (potassium, calcium, iron) that aid in the development of bones and blood. If you eat the recommended number of servings from each of the food groups, you're well on your way to consuming a diet that meets your nutritional needs.
Servings and Portions
A serving of food and a portion of food are not necessarily the same thing. As seen in table 14.3, a serving is a recommended amount. A portion, on the other hand, is the amount of food you put on your plate (or, at a restaurant, the amount put there for you). Therefore, a portion can be large or small. A large portion can contain much more than a recommended serving, and a small portion can contain less than a recommended serving. Use the following strategies to control your portion sizes so that you eat an appropriate amount of food.
- Know the size of a recommended serving (see table 14.3).
- Choose portions equal to recommended servings.
- Eat only part of large portions; save extra food for another meal.
- Read food labels carefully. Calorie totals listed on food labels (see figure 14.6) typically show the number of calories in one serving, but a package often contains several servings. To consume the number of calories on the label, choose only an amount from the package that is equal to a recommended serving.
One reason for Canadians' increase in portion sizes in recent years is the marketing of larger meals sometimes referred to as "super-sized." For example, the original size of most French fry orders contained 450 calories, but the size of a large order currently promoted by many fast food outlets contains more than 600 calories. Another example is the all-you-can-eat buffet offered at a set price, which can motivate people to eat large portions in order to get their money's worth. Use the information presented in table 14.3 in the previous lesson to help you determine how much you eat. You may find that one portion is equal to several servings.
You can also get an idea of appropriate serving sizes by referring to certain common objects typically found around the house. The following list provides some examples of approximate sizes of single servings.
- Baked potato: computer mouse
- Bagel: can of tuna
- Apple: baseball
- Hard cheese: three game dice
- Lean beef: deck of cards
Many teenagers do not shop for groceries, plan meals, or cook for a family. But it's important for you to start learning how to do these things now because you'll need these skills at some point in your life. Reading and understanding food labels can help you plan your diet and shop for healthy foods. By law, manufacturers must now use a standard format for food labels. In 2015, Health Canada made changes to the food label based on feedback from more than 10,000 Canadians. Food manufacturers have until 2020 to institute the proposed changes to the food labels. The changes proposed by Health Canada will appear in the following sections. Be aware that the food labels required by the government are not the same as the food labels sometimes provided by manufacturers on the front of food packages (for example, cereal boxes). Front-of-box labels are not regulated and may not be accurate. In fact, nutrition experts criticize these labels because they are often deceptive and are really part of a strategy to sell the food rather than provide nutrition information. Experts worry that consumers will look at the front-of-box label rather than the regulated side-of-box label that provides scientifically sound information.
Reading food labels will help you select healthy foods.
You've probably already used side-of-box nutrition labels at one time or another, but you may not know how to use them most effectively. When reading a food label, start at the top and use the following six steps, which refer to the sample label from a package of food presented in figure 14.6. (Food labels are typically all white on food containers, but colours are used in this example to help you easily find each area on the label.)
Figure 14.6 Sample food label.
From Canadian Food Inspection Agency.
Step 1: Servings
The number of servings in the container is shown in the green area. In this case, two servings are listed, and the size of each serving is 1 cup, thus making a total of 2 cups in the package. By 2020, food manufacturers in Canada will have to present serving sizes that reflect portions people typically eat. For example, many bread products present a serving size as one slice and provide nutrition information based on that serving, but if you eat a sandwich you typically have two slices.
Step 2: Calories
The white area shows the number of calories per serving - in this case, 130 calories. Therefore, the total calorie content of the food package is 260 (130 calories × 2 servings = 260 calories). Some food labels include both total calories in the package and calories per serving. However, many labels include only calories per serving, which may lead people to think that the calorie number listed (130) is the amount in the total package. The real calorie content is 260 (2 servings × 130 = 260 calories).
Step 3: Nutrients That Should Be Limited
The yellow area presents information about some nutrients that should be limited in your diet, such as fat, salt, and cholesterol. The number beside each nutrient indicates the amount in grams (g) or milligrams (mg) and the percentage of that nutrient's daily amount provided by one serving. In this case, one serving of the food provides 11 percent of the total fat and 1 percent of the salt you should consume each day. If you eat two servings, you need to double the listed numbers to know how much fat and salt you're consuming. Trans fat amounts are shown in figure 14.6 even though they could be excluded from foods in the future. In addition, amounts of healthy fats such as mono- and polyunsaturated fats are provided on some labels.
Step 4: Carbohydrate and Protein
Carbohydrate and protein are two of the three macronutrients that provide your body with energy. Two types of carbohydrate are listed on the label (in blue): dietary fibre and sugars. As shown in pink, 6 percent of the daily requirement of carbohydrate is provided by one serving. Dietary fibre, a type of carbohydrate, is desirable in the diet, and the label helps you determine if you eat enough of it. Sugars should be limited in the diet like fat and sodium. One of the main changes Health Canada will require of food manufacturers by 2020 is to provide more detailed information about added sugars in the ingredients list. Specifically, products that have sugar added (like granola bars, cereal, and fruit bars) will be required to group the different types of added sugars into a category called "sugars." For example, if a product adds brown sugar, fancy molasses, and sugar, the ingredients list would group them as "sugars (brown sugar, fancy molasses, and sugar)." In addition, the ingredients list on products with added sugars must list the ingredients by weight, beginning with the ingredients that contribute the most weight to the product. What this means for many products is that sugars will now appear as the first ingredient (indicating that it is the number-one ingredient by weight). The number of grams of protein is shown on the label in pink. Health Canada recommends 0.8 grams of protein per kilogram of body weight each day (54.5 grams for a person weighing 68 kilograms [150 pounds] ).
Step 5: Micronutrients
Micronutrients, such as vitamins and minerals, are especially important to your diet. You need to get 100 percent of these each day. Six types of micronutrients, four vitamins and two minerals, are highlighted in blue on the label. As you can see from the label in figure 14.6, one serving of the food provides 8 percent of daily calcium and iron, and between 8 and 40 percent of the vitamins.
Step 6: Footnote
Use the information in the white area at the bottom of the label to make adjustments for the total number of calories you consume. The total number of calories needed each day varies from person to person depending on age and body size. People who require more calories need to adjust the nutrient amounts, and the information presented at the bottom of the label helps you make these adjustments. For example, a person requiring 2,200 calories per day is allowed more fat, and needs more fibre, than a person requiring 2,000 calories per day.
Calories from soft drinks add up fast. Most soft drinks contain about 150 calories in a 12-ounce (about 0.4-litre) can - that's 450 calories in three cans - and many teens drink multiple cans per day. A 64-ounce (about 2-litre) drink, such as those sold at many fast food and convenience stores, contains almost 800 calories. Not surprisingly, studies show that excessive consumption of soft drinks may be one reason for the high incidence of overweight in developed countries. In fact, if all other aspects of your diet stayed the same, adding one soft drink a day would cause you to gain about 7 kilograms (~15 pounds) of fat in a year. The solution? Water quenches your thirst and contains zero calories.
Fitness Technology: What's in Your Food?
A calorimeter is an apparatus designed to determine the amount of heat generated by a chemical reaction. In Latin, calor means heat and metron means measure; thus a calorimeter measures heat. A special type of calorimeter is used to determine the amount of heat created when different types of food are burned. In this way, nutrition scientists have determined the calorie counts of various foods. The Dietitians of Canada provides a free website and app (eaTracker) that allows you to determine the calorie counts of many foods. The eaTracker is also a useful tool that can support you in reaching your goals with meal planning, food analysis, and physical activity. The U.S. Department of Agriculture's Food Tracker, a part of the SuperTracker found at the MyPlate website, will also help you determine the calorie counts of various foods. As part of their Healthy Canadians website, the Government of Canada has created a Healthy Eating resource that allows you to gather information about nutrients in foods, healthy eating recommendations, and nutrition programs that support Canadians.
The web has also made it relatively easy for you to find other information about food content. For example, some nutrition websites list the specific nutrient content (carbohydrate, protein, fat, vitamins, and minerals) of various foods. Some address foods of all kinds, and others provide information specifically about fast food.
Find the Dietitians of Canada eaTracker website (www.eatracker.ca). Notice that it includes online tools for meal planning, meal analysis, physical activity tracking, and goal setting. You could also try the SuperTracker at the MyPlate website (www.ChooseMyPlate.gov). Notice that it includes six different online tracking tools, including FoodTracker and Physical Activity Tracker. Alternatively, you could use a free web tool such as Food-O-Meter at webMD.com or MyFitnessPal at MyFitnessPal.com. Try one of the tools and write an evaluation of it that is several paragraphs long. Explain how the tool would or would not be useful.
Learn more about Fitness for Life Canada.