Nutrition Labels
Packaged foods must have a nutrition label like the one depicted in Figure 2A. The information given is based on a serving size (that is, 1 1/4 cup, or 57 grams [g]) of the cereal and on a diet of 2,000 Calories for women and 2,500 Calories for men. A Calorie is a measurement of energy. One serving of the cereal provides 220 Calories, of which 20 are from fat.
Fats
The body stores excess energy from nutrients under the skin and around the organs as fat. An overconsumption of total dietary fat, saturated fat, and cholesterol can lead to obesity and have adverse effects on health. High levels of saturated fat have been implicated in cancer of the colon, pancreas, ovary, prostate, and breast. Cholesterol and saturated fat contribute to the formation of deposits of plaque, which clog arteries (called atherosclerosis) and lead to high blood pressure, strokes, and heart attacks. A 2,000-Calorie diet should contain no more than 65 g (585 Calories) of fat because of health concerns. Knowing how a serving of the cereal will contribute to the maximum recommended daily amount of fat, saturated fat, and cholesterol is important. This information is found in the listing under % Daily Value.
Carbohydrates
Carbohydrates (simple sugars and polysaccharides) are the most readily available source of energy for the body. Breads and cereals contain complex carbohydrates, and foods such as candy and ice cream contain simple carbohydrates. Breads and cereals are preferable because they contain protein, minerals, and vitamins. Complex carbohydrates also contain fiber. Soluble fiber combines with the cholesterol in food and prevents the cholesterol from being absorbed from the digestive tract into the body. Insoluble fiber has a laxative effect. The nutrition label in Figure 2A indicates that one serving of the cereal provides 15% of the recommended daily carbohydrates.
Proteins
A woman should consume about 44 g of protein per day, and a man should have about 56 g of protein per day. Red meat is rich in protein, but it is usually also high in saturated fat. Therefore, it is considered good health sense to rely on protein from plant origins (e.g., whole-grain cereals, dark breads, rice, and legumes such as beans) to a greater extent than is customary in the United States. The nutrition label in Figure 2A shows that 5 g of protein are obtained from each serving of the cereal.
Other Molecules
The amount of dietary sodium (as in table salt) in a food product is of concern because excessive sodium intake seems to further elevate blood pressure in people already suffering from hypertension.
Figure 2A Nutrition label on the side panel of a cereal box.
Sodium intake should be no more than 2,400 milligrams (mg) per day for people with hypertension. What percentage of this maximum amount does a serving of the cereal in Figure 2A provide? Vitamins are organic molecules required in small amounts in the diet for good health. Each vitamin has a recommended daily intake, and the nutrition label on food products tells what percentage of the recommended amount is provided by one serving. The nutrition label for the cereal in Figure 2A indicates that, while the cereal provides no vitamin A or calcium, one serving does contain 10% of the suggested daily intake of vitamin C and 80% of the recommended daily intake of iron.