Obtain a package of your favorite snack food and examine the nutritional information on the label. Confirm the caloric value listed by using the conversions listed in the table in the Chemistry in Action feature 'Energy from Food' (p. 191). Alternatively, you can use the estimates for caloric value for a given food as provided in the table.
b. How long would you have to engage in each of the physical activities to burn the calories contained in your snack?

Verified step by step guidance

1. Step 1: Identify the total caloric value of the snack from the nutritional label. This is typically listed as 'Calories' or 'Energy' on the packaging.
2. Step 2: Break down the macronutrient composition of the snack (e.g., grams of carbohydrates, proteins, and fats) from the nutritional label. Use the following caloric conversion factors: carbohydrates = 4 kcal/g, proteins = 4 kcal/g, and fats = 9 kcal/g.
3. Step 3: Calculate the total caloric value of the snack by multiplying the grams of each macronutrient by its respective caloric conversion factor and summing the results. Use the formula: $\mathrm{Total}=(\mathrm{grams}\times 4)+(\mathrm{grams}\times 4)+(\mathrm{grams}\times 9)$.
4. Step 4: Compare the calculated caloric value to the value listed on the label to confirm its accuracy. Note any discrepancies and consider rounding or estimation errors.
5. Step 5: To determine how long you would need to engage in physical activities to burn the calories, use the caloric burn rate for each activity (e.g., running burns approximately 10 kcal/min, walking burns approximately 4 kcal/min). Divide the total caloric value of the snack by the burn rate for each activity to find the time required. Use the formula: $\mathrm{Time}=\frac{\mathrm{Total}}{\mathrm{BurnRate}}$.

Key Concepts

Nutritional Information

Nutritional information on food labels provides essential data about the contents of the food, including calories, fats, carbohydrates, proteins, vitamins, and minerals. Understanding this information is crucial for making informed dietary choices and managing energy intake. The caloric value indicates how much energy the food provides, which is vital for assessing how it fits into an individual's daily energy needs.

Caloric Conversion

Caloric conversion involves translating the macronutrient content of food into its total energy value, typically measured in calories. Each macronutrient contributes a specific number of calories per gram: carbohydrates and proteins provide 4 calories per gram, while fats provide 9 calories per gram. This conversion is essential for verifying the caloric value listed on food labels and understanding how different foods contribute to overall energy intake.

Physical Activity and Energy Expenditure

Physical activity and energy expenditure refer to the calories burned during various forms of exercise and daily activities. Different activities have different energy costs, often measured in calories per minute. Understanding how long one must engage in specific activities to burn off the calories consumed from food helps individuals manage their weight and maintain a balanced lifestyle by aligning energy intake with energy expenditure.