are you sure its fat free
The food industry bases its figures on the weight of the product and not the calories the product contains.
This is the reason certain foods can be advertised as 97% fat free.
For example, suppose a 10-ounce serving of a food contains 240 calories, and the label states that it contains
9 grams of fat. The food industry then converts 10 ounces
to grams by multiplying each ounce by 29 grams;
hence, the total weight of the product is 290 grams, and if
there are 9 grams of fat, the percentage of fat is
× 100% = 3.1%
The procedure used by the food industry is misleading. The correct way to calculate the fat content is to multiply the number of grams of fat by 9 to get the calories.
(Each gram of fat is converted to 9 calories.) In this case,
9 × 9 = 81 calories. Next, divide the fat calories by the
total calories and multiply by 100% to get the percentage of calories derived from fat. In this case, the label
stated that a 10-ounce serving contained a total of 240
× 100% = 33.75%
Hence, 33.75% of the calories come from fat, not 3%
Gather three of your favorite packaged foods; perhaps one from each: breakfast, lunch and dinner. Use the model explained in the “Are You Sure It’s Fat Free?” to analyze, through the mathematical formula explained, the fat content and protein content from your foods. To analyze the protein content use 4 calories per gram of protein, rather than the 9 calories for grams of fat.