Food Assistance: How Strong Is the Safety Net?
Food assistance programs
increase food spending and combat poverty, but their
effect on nutrition is more uncertain.
Lin, and David
assistance programs, particu-larly the
Food Stamp Program, increase food spending
and household income.
2004, adding food stamp benefits to
recipients' incomes raised 9 percent
of recipients out of poverty.
effects of food assistance programs
article is drawn from . . .
of Food Assistance and Nutrition Programs
on Nutrition and Health: Volume 4, Executive
Summary of the Literature Review,
by Mary Kay Fox, William Hamilton, and Biing-Hwan
Lin, FANRR-19-4, USDA, Economic Research Service,
Stamp Benefits and Childhood Poverty in the
1990s, by Dean Joliffe, Craig Gundersen,
Laura Tiehen, and Joshua Winicki, FANRR-33,
USDA, Economic Research Service, September
may also be interested in . . .
in Food Assistance—How Unemployment
Affects the Food Stamp Program, by
Kenneth Hanson and Craig Gundersen, FANRR-26-7,
USDA, Economic Research Service, October 2002.
Adequacy of Children Participating in WIC,
by Katherine Ralston, EB-8, USDA, Economic
Research Service, April 2006.
Stamps and Obesity: Ironic Twist or Complex
Puzzle?” by Michele Ver Ploeg, Lisa
Mancino, and Biing-Hwan Lin, in Amber
Waves, Vol. 4, No. 1, USDA, Economic
Research Service, February 2006.
Born during the Great Depression,
but growing to maturity during the 1960s, 1970s,
and 1980s, food assistance programs have provided
a safety net to help U.S. households purchase sufficient
food. Safety nets are created for moral, economic,
and political reasons. For economists, a safety
net is a policy that ensures a minimum income, consumption,
or wage level. Safety nets can be viewed as social
insurance to help people through livelihood shocks
and stresses, such as those caused by illness, unemployment,
or job displacement.
An original intent of food
assistance programs was to increase food access
and reduce food
insecurity. During the last few decades, food
assistance programs, particularly the school meals
programs and the Special Supplemental Nutrition
Program for Women, Infants, and Children (WIC),
have also been promoted as a nutrition safety net
offering access to essential nutrients and minerals.
In fiscal year 2005, Federal funding for the food
assistance and nutrition programs was nearly $51
billion, comprising 55 percent of USDA’s budget.
Farmers, food companies, and program participants
have benefited from the increased food spending
and improved food security. Evidence of improved
nutrition for program participants is more difficult
Food Assistance Increases
Food Expenditures . . .
U.S. agriculture and nutrition
policy includes a variety of farm programs and food
assistance and nutrition programs that support an
abundant food supply and affordable prices. The
core food assistance programs, managed and funded
by USDA, include the Food
Stamp Program, the school meals programs, WIC,
and commodity distribution programs. These programs
serve one in every five Americans at some point
during the year. The Federal Government partners
with State and local, public, and private agencies
to administer (and, in some cases, contribute funding
for) its food assistance efforts. Each program has
its own objectives, eligibility criteria, benefit
structure, and legislative oversight.
The Food Stamp Program is the
foundation of the food assistance safety net. It
provides benefits to qualifying families and supports
markets for agricultural products. With program
costs of $31 billion in fiscal 2005, it is the country’s
largest food assistance program. Using normal retail
marketing channels, the Food Stamp Program provides
qualified low-income households with increased purchasing
power to acquire food. It offers the only form of
assistance available nationwide to most households
on the basis of financial need only, irrespective
of family type, age, or disability. For many low-income
households, the program is an important source of
purchasing power. For a typical low-income family
with children, food stamps provide about 25 percent
of the family’s total purchasing power.
The Food Stamp Program increases
household food expenditures. Not only does the program
increase food expenditures beyond what households
would spend without the program, households spend
more on food than they would if the same amount
of benefit were given as cash. A dollar of food
stamp benefit is estimated to increase food spending
by 17 to 47 cents, versus 5 to 10 cents from a dollar
of cash assistance. Although the food stamps themselves
must be spent on food, a dollar of food stamps does
not lead to a dollar in additional food spending
because cash previously spent on food can be used
for rent, clothing, and other nonfood expenses.
. . . Reduces Food Insecurity
. . .
Do food assistance programs reduce
the probability that vulnerable households experience
food insecurity? That is, do the programs lessen
the likelihood that poor families have insufficient
food for an active, healthy life for all household
members? This question was recently answered by
George Borjas of Harvard University through ERS-supported
research. Borjas took advantage of a “natural
experiment” when Federal welfare reform legislation
limited the eligibility of immigrant households
to receive assistance, while some States chose to
continue offering State-funded assistance to immigrant
households. Borjas exploited these changes in eligibility
rules to examine the link between food insecurity
and public assistance.
His research indicates that a
10-percentage-point cut in the share of the population
that receives public assistance increases the share
of food-insecure households by about 5 percentage
points. Borjas’s research supports the hypothesis
that food assistance programs are an important determinant
of providing households with a minimal level of
. . . and Raises Incomes
Food assistance programs reduce
overall economic vulnerability, not just food insecurity—particularly
during downturns in the business cycle. Individuals
with longer term needs resulting from chronic illness,
disability, or old age also rely on these assistance
programs. Food assistance programs targeting those
who may be temporarily affected when events take
an unfavorable turn can be viewed as income insurance
to help people through temporary livelihood shocks,
such as those caused by illness or unemployment.
The Food Stamp Program is particularly
helpful during economic downturns for households
with stronger ties to the workforce. The amount
of food stamps given to a household depends on the
number of eligible people in a household and the
household’s net income. A 4-person household
with zero net income would receive the maximum food
stamp benefit of $506 per month. If the family’s
net income rose by $100 per month, its benefits
would fall to $476.
During a recession, as wages stagnate,
work hours decrease, and jobs are lost, food stamp
benefits increase for current participants, and
more households become eligible. But how many people
turn to the Food Stamp Program in the event of a
recession? ERS research suggests the 1-year effect
of a rise in unemployment by 1 percentage point
is about 700,000 additional food stamp recipients.
Over 5 years, the 1-percentage-point increase in
unemployment leads to a total of 1.3 million additional
A number of other studies indicate
food assistance programs, particularly the Food
Stamp Program, have significant positive effects
on household income. Although recent evidence suggests
a changing relationship between unemployment and
food stamps, historically, program effects have
been countercyclical. That is, more assistance is
provided to households during a downturn in the
economy and less during an economic expansion. A
report by the Congressional Budget Office indicates
that of all the federally funded assistance programs,
for which participant eligibility depends on income
and assets, only the Food Stamp Program was responsive
to changing economic conditions.
Food stamps succeed in raising
participants’ incomes. Adding the dollar value
of food stamp benefits to the income of food stamp
recipients yields a significantly different poverty
distribution. In 2004, adding food stamp benefits
to income was sufficient to raise 9 percent of food
stamp recipients out of poverty. Food stamp benefits
have an even greater impact on the poorest households,
raising 17 percent of food stamp households above
50 percent of the poverty guideline.
Food Stamps Reduce Child
In 2000, 8.8 million U.S. children
received food stamps. To illustrate the efficacy
of food stamps in helping households meet basic
needs, ERS researchers added the value of food stamp
benefits to household income and then measured the
effect on child poverty rates. This “food
stamp effect” reduced the number of children
in poverty in 2000 by 4 percent, lifting about 500,000
children out of poverty. Augmenting income with
the value of food stamp benefits also has the effect
of reducing the depth of child poverty by 20 percent
or more, as measured by the reduction in the poverty
gap or the amount of income needed to raise income
to the poverty threshold.
Nutrition Studies Are Dated,
Recent Results Are Mixed
The positive impacts of food assistance
programs on food expenditures and incomes are clear.
Less certain are the programs’ impacts on
nutrition. ERS has released a series of reports
providing the first systematic and comprehensive
review of the hundreds of studies on the effects
of various food assistance programs—especially
the main four—on nutrition and health.
The WIC program provides low-income
pregnant, breastfeeding, and postpartum women, infants,
and children up to age 5 with specific supplemental
foods, nutrition education, and referrals to health
care and social services. Most studies indicate
the WIC program—with its emphasis on iron-fortified
infant formula, infant cereals, and ready-to-eat
cereals—has helped reduce anemia in children.
Further evidence suggests that WIC has improved
children’s intakes of iron, vitamin B6,
and folate, and reduced their intake of added sugar
and fat. Recent studies, however, have failed to
reproduce earlier work showing that women in WIC
increased their intakes of food energy (calories),
protein, vitamin C, iron, and calcium. Moreover,
recent studies conducted using dietary assessment
methods recommended by the Institute of Medicine
indicate that, today, the vast majority of both
WIC and non-WIC children have nutritionally adequate
Schools that participate in the
National School Lunch Program (NSLP) and School
Breakfast Program receive cash and commodities from
USDA to offset the cost of providing the meals.
In return, the schools serve meals that meet Federal
nutritional standards and offer free or reduced-price
meals to low-income children.
Analyses of the impacts of the
NSLP are anchored by two national evaluations: the
National Evaluation of School Nutrition Programs,
conducted in 1980-81, and the first School Nutrition
Dietary Assessment Study, conducted in 1991-92.
In addition to these national evaluations, studies
have used national survey data or local data sets
to assess impacts.
These evaluations strongly indicate
that the NSLP increases children’s lunchtime
intakes of riboflavin, vitamin B12, calcium,
phosphorus, magnesium, and zinc. Evidence for riboflavin,
calcium, and phosphorus is particularly strong.
Every study that examined intakes of these nutrients
found that NSLP participants had significantly higher
intakes at lunch than non-participants. It is generally
accepted that this pattern is caused by increased
consumption of milk, which is a concentrated source
of all of these nutrients and a feature of NSLP
lunches, by participants.
However, NSLP operations changed
substantially after most of the research on health
benefits was completed. Responding to findings in
the early 1990s that school lunches were high in
fat, saturated fat, and sodium, and low in carbohydrates,
USDA launched the School Meals Initiative for Healthy
Children in 1995 to bring school lunches and breakfasts
in line with the Dietary Guidelines for Americans.
One cannot assume that findings from earlier research
apply to today’s NSLP. An updated survey (currently
underway by USDA) and new research are essential
to understanding the impact of the NSLP as it operates
Studies prior to the School Meals
Initiative indicate that the School Breakfast Program
had no impact on the likelihood of a child’s
eating breakfast, but availability of the program
was associated with a greater likelihood that low-income
students would eat a more substantial breakfast.
The program was found to increase intakes of three
minerals—calcium, phosphorus, and magnesium—both
at breakfast and over 24 hours. (Riboflavin intake
also increased at breakfast, but the effect did
not persist over the full day.) All of these nutrients
occur in concentrated amounts in milk.
The positive effect of the Food
Stamp Program on food expenditures has been extensively
analyzed and confirmed in many studies, with much
of the research using large national surveys. But
increased food spending does not necessarily lead
to improved nutrition. The effect of increased food
expenditures on household availability of food energy
and nutrients is mixed. Early studies of the program
found an effect on certain vitamins and minerals,
while more recent studies of the program as it is
currently structured show increases in the household
availability of food energy and protein. Earlier
studies indicate that the program may increase children’s
intakes of vitamins and minerals, but these findings
were not replicated in the most recent studies.
The most thorough studies of food
assistance programs suggest mixed nutrition effects.
Caution must be used in interpreting results, positive
or negative, from most nutritional studies of food
assistance programs. One cannot logically infer
that food assistance programs have no nutritional
effects from studies that fail to demonstrate positive
Weak evaluation designs and/or
inadequate data limit conclusions that can be drawn
about causality between food assistance participation
and nutrition and health outcomes (see
“Prior Nutrition Research Has Limitations”).
This is particularly true of longer term outcomes,
such as iron deficiency (anemia) and weight status.
Food assistance participation must precede such
outcomes by long enough and be robust enough to
provide a plausible impact. Reliable assessment
of impacts requires measurements both before and
after participation, preferably multiple measurements.
In addition, nutrition outcomes are influenced by
a complex interplay of economic, diet, genetic,
and environmental factors, making it challenging
to isolate the specific impact of food assistance
Prior Nutrition Research Has Limitations
Most existing research on
the nutrition and health effects of food assistance
programs shares three key limitations: the
potential for selection bias, relative age
of the data, and the use of dated approaches
to assessing dietary intakes.
Selection Bias Can Skew Outcomes.
The gold standard for program evaluation
is a randomized experiment where “alike”
individuals are randomly assigned to
two groups—a treatment group that
receives program benefits and a control
group that does not. The randomized
experiment has rarely been implemented
to evaluate food assistance programs,
mainly because it is considered either
illegal or unethical to withhold benefits
from those who meet eligibility requirements
and take the necessary steps to qualify.
The underlying problem is that, without
random assignment, the participant (treatment)
and nonparticipant (control) groups
may not be comparable. For example,
food stamp participants may be more
highly motivated to achieve the program-intended
outcomes than nonparticipants. Researchers
have used a variety of sophisticated
statistical procedures to counteract
selection bias, but some problems remain.
Older Studies Do Not Capture
Program or Population Changes.
Many studies use data sets from the
1980s and even the 1970s. Findings from
these early studies may not apply to
today’s programs because of significant
changes that have occurred inside or
outside the program. For example, there
have been dramatic changes in grocery
store offerings and in Americans’
eating habits over the past 20-25 years.
These changes have affected household
nutrient availability and individual
Finally, the design and implementation
of some food assistance programs, especially
the National School Lunch and School
Breakfast Programs, have changed greatly.
Studies based on data collected before
these changes may not apply to today’s
programs or participants.
Dietary Standards Have Changed.
Most dietary intake studies of food
assistance participants focus on mean
intakes or the percentage of the population
meeting an intake criterion, generally
the Recommended Dietary Allowances (RDAs).
Although a common practice at the time
most of the research was conducted,
this approach fails to capture the true
prevalence of inadequate nutrient intakes.
In 1997, the National Academy of Sciences’
Institute of Medicine began developing
revised dietary standards—the
Dietary Reference Intakes (DRIs)—as
well as a recommended method for estimating
nutrient inadequacy within population
groups. In particular, the Institute
recommends using longrun average, or
“usual,” intake, leading
to lower estimates of the prevalence
of nutrient inadequacy. Researchers
have just begun to use these improved
dietary assessment methods.