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The ERS Loss-Adjusted Food Availability data (previously known as
the Food Guide Pyramid Servings data) are derived from ERS per
capita food availability data adjusted for food spoilage and
other losses to more closely approximate actual per capita intake.
The “loss-adjusted” food availability data are converted
into daily per capita food intake, which is presented in two
forms: the estimated number of calories consumed daily (per capita)
and the estimated number of MyPyramid equivalents consumed daily (per capita) (as defined
by the 2005 Dietary Guidelines for Americans and its supporting
guidance document MyPyramid Plan). These daily allowances were previously called Food Guide Pyramid Servings.
Coverage of the Data
Per capita calorie consumption and MyPyramid equivalents
are estimated for more than 250 agricultural commodities from
1970 to the most recent year of data available. Servings data
for individual commodities are aggregated into food groups to
ease comparison with recommendations for MyPyramid equivalents for the
U.S. population. Per capita calorie consumption is reported for
individual commodities and aggregated food groups.
History Behind the Data
In the mid-1990s, ERS undertook a major effort to expand the
usefulness of the food availability data for diet and nutrition
monitoring by converting the annual food availability data into
daily individual intake and by adjusting the data for estimated
spoilage and losses in the home and marketing system. The release
of the Food Guide Pyramid in 1992 provided researchers with a
new framework for assessing U.S. dietary status—one that
went beyond a traditional approach (adequacy of individual nutrients)
to a food-based approach linking diet and chronic disease risk.
While ERS recognized that adjusting the food availability data
for spoilage and waste was key to the integrity of the individual
servings series, data to make such adjustments were sketchy and
unreliable. Adjusting the data for losses would likely introduce
unknown errors into the series. There were no well-documented
estimates for food losses at the different marketing levels (for
example, farm, retail, or consumer) or for individual food commodity
groups (for example, peaches, corn, or beef). ERS first attempted
to estimate losses from the food available for consumption in
three selected sectors of the marketing system: retail stores,
foodservice institutions, and the home. ERS gathered existing
food loss coefficients from published literature and discussions
with commodity experts and applied these coefficients to the
food availability data for 1995.
ERS published this research in an article titled, “Estimating
and Addressing America's Food Losses,” in the January-April 1997 edition of FoodReview magazine. The
focus
of this article
was to understand the magnitude of food losses at the retail,
foodservice, and consumer levels and to look for solutions to
reduce these losses through food recovery, recycling, and education.
Losses were estimated for over 250 individual foods and commodity
groups aggregated into 10 food groups. Total losses varied by
food group. For example, in 1995, the fresh fruit and vegetable
category had the greatest food losses at 19.6 percent while the
added fats and oils category had losses amounting to 7.1 percent.
In 1998, ERS released a second report titled “A
Dietary Assessment of the U.S. Food Supply: Comparing Per Capita
Food Consumption
with Food Guide Pyramid Serving Recommendations.” This publication
applied the loss coefficients used in the previous study to a
broader time period (1970-96), and in the process assumed that
the loss rates remained constant over time. Servings based on
the 1996 Food
Guide Pyramid, Home and Garden Bulletin Number 252 were calculated for the same 250 individual foods and commodity
groups, which were aggregated into 5 Pyramid food groups, plus
added sweeteners and added fats and oils.
The loss factors presented in the data
tables are tentative
and are intended to serve as a starting point for additional
research and discussion. Many of the studies on which the loss
coefficients used in this research are based date from the mid-1970s
or earlier. Dramatic changes have occurred in the food marketing
system since then, including innovations in processing technology
and unprecedented growth in the foodservice sector. While ERS
has several efforts underway to improve the data—especially
updated data on foodservice, processing, and household food losses—additional
research is needed to add precision to these estimates and to
provide a more complete picture of food loss across the entire
marketing system. ERS welcomes suggestions to expand on and improve
its loss estimates.
Constructing the Data
The current ERS per capita food availability
data were converted into
daily per capita food servings comparable with those specified
in the 2005 Dietary Guidelines and MyPyramid Plan using
a multistage process. Each commodity was assigned to one of the
five major
food groups (fruits, vegetables, meat, dairy, and grains), or
to one of two additional groups for added fats and oils and added
sweeteners. Next, the data were adjusted for spoilage and other
losses by subtracting estimated losses from the consumption weight
reported in the food availability data. Loss was estimated at
several different stages in the marketing system (retail, household,
institution) and averaged 27 percent of total
available food supplies in 1997. Cooking losses for selected commodities and
nonedible portions of all foods—seeds, pits, and inedible
peels—were also subtracted from the data. Next, the data
were converted from pounds per capita per year to ounces per
capita per day to be comparable to MyPyramid servings.
For each food supply commodity, a serving was defined, based
on the serving size identified in the 2005 Dietary Guidelines and MyPyramid
Plan, and on the weight identified in USDA's Nutrient
Database for Standard Reference (NDB). For example, the Food
Guide Pyramid defines one medium apple as a serving of fruit
and the NDB indicates that a medium apple with skin weighs 138
grams.
After defining Pyramid
serving weights for each commodity, daily
per capita consumption—adjusted for loss and nonedible
parts—was converted into grams and divided by the assigned
MyPyramid serving weight to calculate the number of per capita
MyPyramid equivalents for that commodity. Next, per capita servings
for individual commodities were aggregated to determine total
daily servings for each Pyramid Food Group and were then compared
with recommended servings for the U.S. population. This analysis
used the recommended servings for a sample diet of 2,200 calories,
because it approximates the daily Recommended Energy Allowance
(REA) of 2,247 calories for the United States, derived from the
population-weighted average of REAs for different age and
gender groups in the population. The Food Guide Pyramid bulletin
identifies the daily energy intake of 2,200 calories as appropriate
for most children, teenage girls, active women, and sedentary
men. For more historical information on the data series and its
construction, see A
Dietary Assessment of the U.S. Food Supply: Comparing Per Capita
Food Consumption with Food Guide Pyramid
Serving Recommendations.
Limitations of the Data
Just like the basic food availability data, the loss-adjusted
data series does not measure actual consumption or the quantities
ingested because neither series is based on direct observations
of individual intake. Therefore, data are not available by demographic,
State, or regional breakdowns, and it is not known where readers can obtain such data.
The limited ability of researchers to measure food loss accurately
suggests that actual loss rates, and hence the serving and calorie
estimates on which they depend, may differ from the estimates
reported here. Estimates of retail, foodservice, and consumer
food losses are probably understated due to limitations in the
underlying published studies. Food loss, particularly at the
consumer level, is by nature difficult to measure accurately.
Participants and household surveys on food waste, for example,
tend to be highly "reactive"—changing their behavior
during the survey period out of reluctance to acknowledge how
much food they typically discard, or misstating their true levels
of product discard.
In particular, food loss for individual commodities may well
vary over time, yet the ERS data currently do not capture these
changes. Some of the apparent increase in food loss probably
stems from increased waste and more trimming of food. Processed
foods, such as frozen dinners, generally have more trimmed than
if the raw ingredients were prepared at home. Smaller households,
with increased away-from-home eating, may also have more waste.
On the other hand, new food technologies and food production
and processing practices, such as improvement in the preservation
of bread, may reduce food losses over time.
Usefulness of the Data
Even with these limitations, both the per capita food availability
and per capita loss-adjusted food availability data are useful
for economic analyses because they serve as indirect measures
of trends in food use. In other words, both data series provide
an indication of whether Americans, on average, are consuming
more or less of various foods over time.
By converting the food availability data into daily individual
food servings comparable to Food Guide Pyramid serving recommendations,
ERS has contributed to the existing dietary assessment literature.
Researchers and policymakers can use these data to measure changes
in food consumption behavior over time relative to major nutrition
education or policy initiatives. Also, because the food servings
data were derived from consumption data for raw and semi-processed
agricultural commodities, rather than for final food products,
food servings could be readily converted back to farm-level data,
easing the translation of dietary recommendations into production
and supply goals for farmers and the food industry. Finally,
the time-series estimates reported here can be used as a baseline
to project future trends in food demand and for comparing these
trends against recommendations for MyPyramid equivalents.
For example, a 2006 ERS report “Possible
Implications for U.S. Agriculture From Adoption of Select Dietary
Guidelines” provides
one view of the potential implications for U.S. agriculture if
Americans fully met the recommendations in the 2005 Dietary
Guidelines for Americans and MyPyramid Plan for
fruit, vegetables, milk, and whole grains. A straightforward
extrapolation using ERS loss-adjusted
food availability data (previously known as the Food Guide Pyramid
Servings data) for these food groups suggests that the potential
long-term impact on food demand and production in the United
States could be substantial.
The data are also useful for helping researchers better understand
the differences and similarities between the food supply data
and USDA's Continuing
Survey of Food Intakes by Individuals (CSFII),
which measures food products actually eaten by individuals. In
essence, the serving estimates allow researchers to compare the
amount and types of food available in the food supply with information
on actual food intakes by Americans.
 For more information, see Estimating
and Addressing America's Food Losses, A Dietary Assessment
of the U.S. Food Supply: Comparing
Per Capita Food Consumption with Food Guide Pyramid Serving Recommendations, and the Food
Availability documentation. See also Related
Resources and Glossary.
View or download Excel spreadsheets of Loss-Adjusted Food Availability data.
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