Possible Implications for U.S. Agriculture From Adoption of Select Dietary Guidelines
by
Jean C. Buzby,
Hodan Farah Wells, and
Gary VockeEconomic Research Report No. (ERR-31) 35 pp, November 2006
The latest Dietary Guidelines for Americans was released in
January 2005. In April 2005, the Guidelines' companion MyPyramid
Food Guidance System was released and replaced the 1992 Food Guide
Pyramid. A major focus of the new Guidelines is to encourage
Americans to consume fruit, vegetables, dairy products
(particularly fat-free or low-fat milk products), and whole-grain
products, while staying within caloric recommendations.
What Is the Issue?
Currently, the average American diet falls short of the daily
recommendations for fruit, vegetables, whole grains, and milk and
milk products in the 2005 Dietary Guidelines for Americans and in
the supporting MyPyramid Food Guidance System. If Americans were to
bring their diets fully in line with these recommendations, changes
in the mix and quantity of foods produced in the United States
would undergo some major shifts.
What Did the Study Find?
If Americans were to fully meet the Guidelines' recommendations
for fruits, vegetables, total grains, and whole grains, U.S.
agriculture would need to harvest 7.4 million additional acres of
cropland per year, an increase of 1.7 percent of total U.S.
cropland in 2002. Additionally, U.S. dairy farmers would need to
raise annual production of milk and milk products by an estimated
108 million pounds (about a 65-percent increase) for Americans to
meet recommendations for dairy consumption. Such an increase in
dairy demand would likely require an increase in the number of
dairy cows, an increase in the volume of feed grains needed, and,
possibly, an increase in the acreage devoted to dairy
production.
Fruit. Americans would need to increase daily
fruit consumption by 132 percent to meet the new dietary
recommendations. The additional demand could require U.S. producers
to more than double harvested fruit acreage to 7.6 million acres
(from 3.5 million). U.S. fruit production is constrained by land,
labor, and climate, making it likely that imports would continue to
increase as a share of the total U.S. fruit supply.
Vegetables. To meet the new recommendations for
vegetables, Americans' daily vegetable consumption would need to
rise by about 31 percent and the mix of vegetables consumed would
need to change. For example, consumption of legumes would have to
increase by 431 percent, and consumption of starchy vegetables
would have to decline by 35 percent. To meet this increased demand,
the area harvested for vegetables in the United States would need
to increase by about 137 percent from 6.5 million acres to 15.3
million acres.
Milk and milk products. Americans would need to
increase their consumption of dairy products, including fat-free or
low-fat milks and equivalent milk products(e.g., nonfat yogurt), by
66 percent (requiring an additional 111 billion pounds of milk per
year) to meet the new dietary recommendations. Domestic production
could account for 108 billion pounds of that increase, most likely
by expanding dairy cow inventories, an action counter to long-term
industry trends.
Whole grains. To meet the dietary
recommendations, Americans would need to increase their daily
consumption of whole grains by an estimated 248 percent and reduce
their consumption of total grains by about 27 percent. Because it
takes less raw wheat to produce a whole-grain product than a
similar refined-grain product and because of the decline in
total-grain intake, the overall drop in demand could translate to
producers' harvesting about 5.6 million fewer acres of wheat each
year.
How Was the Study Conducted?
The authors used both the ERS Food Availability data and the ERS
Food Guide Pyramid Servings data, which are the ERS Food
Availability data adjusted for plate waste and other food losses
and converted to daily per capita servings. These data series are
proxies for actual food consumption. The authors assumed a
consumption level of 2,000 calories per day for the average
American, which corresponds with the level used throughout the
examples in the Dietary Guidelines and which is consistent with the
level on the Nutrition Facts labels that the Food and Drug
Administration requires on most packaged foods.
The analysis is a straightforward extrapolation from the data,
not an equilibrium model. For each food group covered here, the
authors calculated the percent change in per capita daily
consumption needed to meet the dietary recommendation and then
multiplied this percent change in consumption by the total
availability of that food group in the United States to estimate
the new level of food needed. Within each food group, the authors
then calculated the change in U.S. production needed to meet the
new recommendations using the consumption change estimates and
calculated the domestic acreage needed to meet the new production
levels. For these calculations, the authors (1) fixed the
consumption mix of individual foods at 2003 levels (i.e., no
substitution), (2) held exports constant at the average of
1999-2003 levels, and (3) fixed relative shares of production and
imports at the average of 1999-2003 levels.
The analysis did not analyze the decreases in meat, added fats
and oils, and caloric sweetener consumption needed for Americans to
meet the Guidelines' recommendations. Had these food groups been
incorporated in this analysis, their impacts may have offset the
increases in consumption and production noted here, but, without
explicit analysis, the net effect is uncertain.