This summary report presents historical data on the nutrient content of the U.S. food supply. The data and trends presented in this report are invaluable for monitoring the potential of the food supply to meet nutritional needs; for examining relationships between food supplies, diet, and health; and for examining dietary trends of Americans.
Additionally, food supply nutrient estimates reflect Federal enrichment and fortification standards and technological advances in the food industry and contribute to the Federal dietary guidance system. Data are provided for food energy and the energy-yielding nutrients—protein, carbohydrate, and fat (total, saturated, monounsaturated, and polyunsaturated fatty acids); cholesterol; dietary fiber; 10 vitamins; and 9 minerals. Included are estimates of quantities of food energy and nutrients per capita per day for the years 1909 through 2004. Estimates of percentage contributions of nutrients by major food groups available for consumption are provided by decades from 1909-19 to 1990-99 and for individual years from 2000 to 2004.
From 1909-19 to 2004, the availability of food energy and many nutrients increased in the food supply. The availability of more food energy reflects higher levels of most macronutrients, principally fat in the 2000s, than in the early years of the series. Levels for most vitamins and minerals were higher in 2004 than in 1909. Higher levels of thiamin, riboflavin, niacin, and iron reflect Federal enrichment standards and the greater use of enriched grain products.
The higher folate level in 2004 reflects folate fortification of grain products beginning in 1998. The level of vitamin A was higher in 2004 than in 1909, but this level fluctuated over the series, depending on the mix of animal and plant foods in the food supply, as well as that available because of fortification of certain foods with vitamin A. The higher carotene level is linked to the increased use of vegetables, such as broccoli and carrots; whereas, the higher vitamin C level in 2004 was due to increased fruit availability, especially citrus fruits since the early 1900s.
The higher vitamin E level in 2004 reflects the greater use of vegetable fats and oils and is associated with increases of polyunsaturated fatty acids. Higher calcium and phosphorus levels in 2004 reflect the increased consumption of lowfat milk, cheese, yogurt, and other dairy products, such as dairy desserts; whereas, higher levels for vitamin B12 in 2004 were due to increased use of poultry, fish, and lowfat milk. Higher sodium levels indicate the availability of more processed foods, such as cheese and canned vegetables.
The higher levels of both iron and zinc in 2004 were mainly due to increased availability of grain products, dairy products (especially lowfat milk and cheese), and poultry; whereas, the higher level of selenium in 2004 than in 1909-19 was due to increased availability of meat, poultry, legumes, nuts, and soy. Levels for potassium were lower in 2004 than in 1909. This lower level of potassium reflects lower consumption of vegetables, especially white potatoes. The levels of vitamin B6, magnesium, and copper were similar throughout the series; whereas, levels for fiber were lower in 2004 than in 1909.
The lower level of dietary fiber in 2004 was attributable to decreased consumption of grains, fresh vegetables (mainly potatoes), and non-citrus fresh fruits since 1909. This publication is an update of Home Economics Research Report No. 56, “Nutrient Content of the U.S. Food Supply, 1909-2000,” issued in 2004. It includes revised estimates for 1909 through 2000 as well as new estimates for 2001 through 2004.
This publication is different from previous reports in that it presents data on nutrients by decade beginning with 1909-19 to 1990-99 and for individual years 2000-2004.