4
Sentinel Populations

Key Messages Noted by Participants

  • Study of some specific groups within a population may provide insights into the relationship between food insecurity and obesity in broader populations.

  • Economic and cultural variations between specific groups may be related to varying rates of obesity later in life, although obesity is high throughout the general population.

  • Government food and antipoverty programs have varying impacts on specific population groups because of geographic, cultural, linguistic, and political differences.

  • Young, low-income children may be an important sentinel population, if food insecurity influences nutritional programming during development and increases risk of obesity later in life.

  • New immigrants have high rates of food insecurity and share characteristics that may mediate between food insecurity and obesity.

  • Very high rates of obesity and food insecurity among Native Americans point to possible causal mechanisms linking the two.

  • In rural populations, the relationship between food insecurity and obesity is likely bidirectional and may be affected by the persistent poverty, reservation of food for children, tendency to binge when food is available, and lack of quality mental health services and health promotion programs, all of which have been reported in these populations.



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4 Sentinel Populations Key Messages Noted by Participants • Study of some specific groups within a population may pro- vide insights into the relationship between food insecurity and obesity in broader populations. • Economic and cultural variations between specific groups may be related to varying rates of obesity later in life, although obesity is high throughout the general population. • Government food and antipoverty programs have varying im- pacts on specific population groups because of geographic, cultural, linguistic, and political differences. • Young, low-income children may be an important sentinel population, if food insecurity influences nutritional program- ming during development and increases risk of obesity later in life. • New immigrants have high rates of food insecurity and share characteristics that may mediate between food insecurity and obesity. • Very high rates of obesity and food insecurity among Native Americans point to possible causal mechanisms linking the two. • In rural populations, the relationship between food insecurity and obesity is likely bidirectional and may be affected by the persistent poverty, reservation of food for children, tendency to binge when food is available, and lack of quality mental health services and health promotion programs, all of which have been reported in these populations. 51

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52 HUNGER AND OBESITY In the third session of the workshop, four speakers discussed “sen- tinel populations”—specific groups within a population that might help to elucidate possible links between food insecurity and obesity. As modera- tor Mariana Chilton, associate professor in health management policy at Drexel University, pointed out, such groups cannot easily and clearly be bounded. Children, immigrants, American Indians, and rural populations— the four groups discussed in the session—could all be represented in the same household. Nevertheless, focusing on distinct subgroups within an overall population offers a way to examine more closely the relationship between food insecurity and obesity. YOUNG CHILDREN AS A SENTINEL POPULATION John Cook, associate professor in the Department of Pediatrics at the Boston University School of Medicine, has been studying children under the age of 3 years in five states as a sentinel population to detect the effects of food insecurity on child health. He began his talk by pointing out, as described in Chapter 2, that the link between food insecurity and obesity is elusive. Although a few studies have found that children living in food- insecure households are more likely to be obese than children who are food secure, most studies have found no evidence of a direct relationship (Larson and Story, 2010). Still, the question remains whether sentinel surveillance of a population of young children could yield useful information about the prevalence or incidence of obesity among different groups, including the overall population of young children, subpopulations of young children, subpopulations distinguished by socioeconomic status (SES) or ethnicity, adolescents, all children, or adults. Sentinel surveillance is a system in which a prearranged sample agrees to report all cases of one or more notifiable conditions. Such systems have been established for HIV infection, sexually transmitted diseases, influenza, and other diseases. Surveillance involves monitoring the rate of occurrence of specific conditions to assess the stability or change in health levels of a population. The study of disease rates in a specific cohort, geographic area, or population subgroup can point to trends in the larger popula- tion, revealing notable changes before they affect the general population, said Cook. A subpopulation may be especially vulnerable to a disease and experience higher disease rates before the general population. It also could be a subpopulation in which the occurrence of or exposure to a disease at one age or life-cycle phase reliably predicts occurrence of disease at a later age or life-cycle phase. “That is the sense in which it makes sense to think of young children as a sentinel population,” Cook said. The prevalence of obesity varies by age and race/ethnicity (Figure 4-1). The prevalence is not as high for younger children ages 2 through 5 years

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53 SENTINEL POPULATIONS 30 25.1 24.4 25 21.7 Non-Hispanic White 19 19.4 20 Percentage Non-Hispanic Black 15.6 14.2 15 Hispanic 11.4 9.1 10 5 0 6-11 Years 2-5 Years 12-19 Years FIGURE 4-1 Obesity (gender- and age-specific BMI ≥ 95th percentile) prevalence by age and race/ethnicity, National Health and Nutrition Examination Survey 2007-2008. Obesity rates are higher for non-Hispanic black and Hispanic children than for non-Hispanic white children at different ages. SOURCE: Adapted from Ogden et al., 2010. Figure 4-1 for NAP.eps as for older children. However, the prevalence of obesity for this group has risen over time, although it has leveled off in recent years (Figure 4-2). Obesity Across the Life Span Research that has examined the link between obesity in young children and later obesity has found strong links. According to Guo et al. (2002), children and adolescents with a high body mass index (BMI) percentile according to the Centers for Disease Control and Prevention’s (CDC’s) BMI-for-age growth charts have a high risk of being overweight or obese at age 35, and the risk increases as those individuals grow older. Stettler et al. (2003) proposed that early infancy is a critical period for the develop- ment of obesity, based on their findings that rapid weight gain during early infancy is associated with obesity in childhood as well as young adulthood. Whitaker et al. (1997) report that if parents are obese, it increases their children’s risk of adult obesity more than twofold, regardless of their obe- sity status during childhood. They also report that obese children under age 3 years without obese parents are at a low risk for adult obesity, but obesity among older children is an important predictor of adult obesity, whether or not the parents are obese. Additionally, food insecurity had significant effects on parental depres- sion, which in turn affected physical health, according to Bronte-Tinkew et al. (2007). They also reported that food insecurity affected parenting

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54 HUNGER AND OBESITY 12 10.4 10.4 10 8 7.2 Percentage 6 5 5 4 2 0 1971-1974 1976-1980 1988-1994 1999-2000 2007-2008 NHANES I NHANES II NHANES III NHANES NHANES Gender- and Age-Specific BMI ≥ the 95th FIGURE 4-2 The prevalence of obesity (gender and age-specific BMI ≥ 95th percen- tile) among children ages 2-5 has increased over the past four decades. SOURCE: Adapted from Ogden et al., 4-2 for NAP.eps Figure 2002, 2010. practices, which were significantly associated with infant feeding and sub- sequent toddler overweight. Perinatal Risk Factors Perinatal risk factors can affect birth outcomes and obesity. The In- stitute of Medicine (IOM/NRC, 2009a) has recommended weight gain between 16 and 40 pounds during pregnancy depending on the anthropo- metric characteristics of the mother. From 1990 to 2006, the proportion of mothers who gained less than 16 pounds increased nearly 50 percent, from 8.3 to 12.3 percent (Martin et al., 2009). Over the same period, the percent- age gaining more than 40 pounds rose 30 percent, from 16 to 20.7 percent. Weight gain of fewer than 16 pounds during pregnancy is associated with increased risk of intrauterine growth retardation, shortened period of gesta- tion, low birth weight, and spontaneous preterm birth. Weight gain of more than 40 pounds is linked with elevated risk for the mother of gestational diabetes, long-term maternal weight retention, and other adverse maternal outcomes. In addition, during the 1990s the diabetes rate during pregnancy increased by an average of 3 percent per year, and between 2000 and 2006 the pace of increase rose to 6 to 7 percent per year. Young children at both ends of the birth weight spectrum seem to be at risk with regard to weight gain during pregnancy. Gilbert et al. (2010) con-

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55 SENTINEL POPULATIONS cluded that “increasing epidemiological evidence links low birth weight to a syndrome of metabolic changes. These adverse health conditions include increased risk of developing obesity when embryo/fetal undernutrition oc- curred during the first half of pregnancy.” Other evidence indicates that larger babies are at greater risk for eventual obesity, measured by overall BMI (Oken and Gillman, 2003). Nutritional Programming The observations on perinatal risk factors relate to the idea of nutri- tional programming, which refers to the concept that an insult or stimulus applied at a critical or sensitive period may have long-term or lifetime ef- fects on the structure or function of an organism (Lucas, 2005). A growing body of evidence shows that too little or too much maternal weight gain in pregnancy can influence nutritional programming and obesity in offspring. Low birth weight infants are at greater risk for central obesity, while high birth weight infants are at risk of high BMI and obesity. Given these observations, young children may be a sentinel population for obesity, Cook said. Low-income young children may be an especially rel- evant sentinel population if food insecurity influences nutritional program- ming through the lack of availability of food to the mother during pregnancy. However, additional research is needed to clarify whether food insecurity influences nutritional programming and—if so—how, Cook said. IMMIGRANTS One way in which immigrants differ from other possible sentinel popu- lations is that fewer data are available to draw conclusions, said Sara Quandt, professor of epidemiology and prevention at Wake Forest Uni- versity School of Medicine. She therefore drew from small-scale studies and personal experiences to describe food insecurity and obesity among immigrants. In 2008, about 12.5 percent of the U.S. population was foreign born, representing an increase from 11.1 percent since 2000. About two-thirds of the growth in the U.S. population over those 8 years is attributable to the native-born population, and about one-third is due to immigrants. Mexico is the leading region of origin for immigrants to the United States. South and East Asia represent the next-largest contributor, followed by the Carib- bean and Central and South America. Combining Mexico and Central and South America, 45 percent of the foreign-born population in the United States comes from Latin American, stated Quandt. Although immigrants come from many regions, they tend to move to particular regions in the United States. Table 4-1 lists the states with

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56 HUNGER AND OBESITY the largest foreign-born populations. Border states and traditional entry points for immigration top the list, but some states that traditionally have not had large foreign-born populations now do. For example, Geor- gia had a 58 percent change in immigration between 2000 and 2008; Virginia, a 39 percent change; and North Carolina, almost 50 percent. Immigrants to these and other states were moving to regions that do not have long-standing and established immigrant communities. It’s quite a different thing for these immigrants to arrive in Georgia, where there are few services equipped to help them, than to arrive in California or in Texas, said Quandt. The age structure of new immigrants also tends to be different than for native populations of earlier immigrants. There are few foreign-born His- panic children in the United States; most of the children in this population are native born, many living in families where their parents and perhaps older siblings are foreign born. Quandt focused specifically in her talk on the Latino population in the United States. Among the most important considerations in the life of new immi- grants is documentation status. “Those of you who work with immigrant populations and listen to what they say know that this runs everything. We have a lot of people here without legal documents, they’re reluctant to access services, they’re reluctant to drive, and in most states now they can’t TABLE 4-1 Change in the Foreign-Born Population, by State, 2000 and 2008 Percentage Change, Change, State 2008 2000 2000-2008 2000-2008 California 9,856,283 8,885,299 970,984 10.9 New York 4,224,175 3,864,227 359,948 9.3 Texas 3,874,847 2,900,232 974,615 33.6 Florida 3,404,395 2,666,010 738,385 27.7 Illinois 1,787,358 1,533,949 253,409 16.5 New Jersey 1,727,049 1,471,566 255,483 17.4 Arizona 938,300 662,174 276,126 41.7 Massachusetts 934,858 771,627 163,231 21.2 Georgia 911,770 578,636 333,134 57.6 Washington 806,131 616,840 189,291 30.7 Virginia 793,415 569,787 223,628 39.2 Maryland 707,450 516,935 190,515 36.9 Pennsylvania 664,202 507,847 156,355 30.8 North Carolina 642,409 432,083 210,326 48.7 Michigan 580,382 521,150 59,232 11.4 SOURCE: Pew Hispanic Center, 2010.

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57 SENTINEL POPULATIONS get drivers’ licenses, and so they have to have a very good reason to drive somewhere. Going to a grocery store or to a WIC [Special Supplemental Nutrition Program for Women, Infants, and Children] program may not be a good enough reason to put themselves at risk.” Even those who have legal documents fear that they will be assumed to be illegal, in which case they could be locked up and their children could come home from school and find no one there, noted Quandt. Many immigrant families have mixed documentation status. A child born in the United States is a citizen while parents may not have the appro- priate documents. “What happens is that the attitudes and activities of the family go to the lowest common denominator. If somebody in the family is not documented, then everybody acts like they’re not documented.” Eligibility for government benefits is another important consideration. Welfare reform has created considerable confusion about public assistance. Many immigrants have lost eligibility for SNAP (Supplemental Nutrition Assistance Program) and other programs. Many people do not know about benefits even if they are eligible for them, or people may harbor misconcep- tions about programs—for example, that they will need to pay back any money they receive. Finally, many immigrants are ashamed to admit that they lack food. “Oftentimes, people come and they live in communities with others from back home, and they’re very much afraid that word is going to get home that they can’t take care of their children.” Immigrants have to change the ways they shop, produce, and consume food in a new country. Many were food producers, and now they are food purchasers. They are exposed to an abundance of low-priced, high-sugar, high-fat foods. They also have access to unfamiliar foods, and they may have substandard housing or an inability to cook or store food. Many immigrants do not speak English, and those from Latin America may speak many different languages as a first language, with some of these languages being unwritten. New immigrants tend to be poor, with low- wage jobs, precarious employment, and seasonal pay cycles. They deal with racism and discrimination, which affects their willingness to use services and may restrict where they buy food. Sometimes women are working outside the home for the first time. Many of these households are transnational, so parents have left even their young children in their home country with grandparents. They need to send money home, so getting them to talk about food security is difficult. They see their family here and there as part of the same network, which creates complex issues for measures of food insecurity.

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58 HUNGER AND OBESITY Food Insecurity and Obesity Among Immigrants Several small studies indicate that these families experience considerable food insecurity (Kasper et al., 2000). For example, one early-childhood longi- tudinal study has found that the children of foreign-born mothers have about twice as high rates of food insecurity as the children of native-born mothers (Kalil and Chen, 2008). However, the evidence for food security and obesity being connected in this population is “very mixed,” said Quandt. Some stud- ies say yes and some say no. The results appear to be closely related to issues of sampling and measurements, said Quandt (Quandt et al., 2006). Despite the ambiguity of current evidence, mixed-method studies that combine quantitative and qualitative approaches point to factors that could potentiate the relationship between food insecurity and obesity, including monotony, emotional eating, feeding children preferentially, and cycles of food restriction. For example, fathers might leave the house so that children are able to eat, or mothers will not eat so children can eat. Families also might choose less expensive items that are assumed to be equivalents, such as fruit-flavored sweetened beverages instead of orange juice. Acculturation appears to be related to obesity (Rosas et al., 2009). For example, boys have higher rates of obesity than do girls depending on whether the mother was born in the United States, moved to the country as a child, or moved as an adult (Van Hook et al., 2009). Language profi- ciency is also relevant. The lower the language proficiency of the mother, the more obesity is seen. Quandt pointed to several high-priority research topics: • Focusing on the heterogeneity of immigrants, including their country of origin, where they live, parental SES, and the gender of children • Documenting variation in the food insecurity experiences among immigrants, including persistent food insecurity and cyclical food insecurity • Untangling the processes by which food insecurity can affect body weight among immigrants “I’m a big proponent of mixed methods simply because then we can start to understand what’s going on,” Quandt said, in particular, how food ways and physical activity patterns change in immigrants. Quandt suggested longitudinal and retrospective studies to trace food security and other experiences over time. NATIVE POPULATIONS Researchers need to avoid what Derek Sayer termed the “violence of abstraction,” said Kathleen Pickering Sherman, professor and chair of the

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59 SENTINEL POPULATIONS Department of Anthropology at Colorado State University. These are real lives and real people. “There’s a lot of joy and humor on the Indian reser- vations where I’ve had the privilege to work, and I hope to share some of that with you as well,” she said. As with the immigrant population, incredible diversity exists across the 564 federally recognized tribes. This diversity further increased when the U.S. census made it possible to report ethnicity as mixed and more people began self-reporting as having Native ancestry. One-third of Native people live on reservations and Designated Statistical Areas, which refers mostly to Oklahoma. Some live in cities, while others live in extremely isolated reservations. A handful of very wealthy tribes have been able to profit from casinos, but that is not the experience of most Native people in the United States. Approximately 26 percent of American Indians in the United States live below the poverty line, and in some reservations, such as the Pine Ridge Reservation in South Dakota where Pickering Sherman has worked, more than half of the people live in poverty. All Native populations have “the shared history of land alienation, dispossession of resources, and having to adapt to a government that was imposed on them.” American Indians and Alaskan Natives, even those who are full-time, year-round wage workers, earn much less than the median income for the U.S. population as a whole. Also, the returns on education for Native Ameri- cans in general are lower than for other groups, in part because of their dedi- cation to returning to and giving back to their reservation communities. Among American Indians, 67 percent are overweight, and 34 percent of American Indian and Alaskan Native men and women are obese. These “astronomical” rates of obesity have dire health consequences. One in six American Indians is diagnosed with diabetes, and 95 percent of those with diabetes are overweight. Tribes such as the Pima demonstrate amazingly high rates of diabetes—more than 50 percent—so much so that they have become a research gateway for looking at the effects of genetics on obesity for Native Americans. Policy clearly plays a role in these rates, because in some cases the same tribal ethnic communities reside on both sides of the Mexican or Canadian borders, yet there are different rates of obesity for the populations across the borders. “There’s something more than just genetics going on,” said Pickering Sherman. Access to Food For many people on reservations, access to food can be a great chal- lenge. Many reservations have significant food deserts,1 where people have 1 A geographic area, particularly lower-income neighborhoods and communities, where ac- cess to affordable, quality, and nutritious foods is limited (IOM/NRC, 2009b).

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60 HUNGER AND OBESITY to go a long way to get food. As one person interviewed on a reservation said, “We don’t have big stores like in Rapid [City]. If you’ve gone into Sioux Nation [the local grocery store], and look, the first thing you see is pop, chips, donuts, and candy, and all of the fruits in the back. All of the [healthful food] is in the back of the store, everything that’s bad for you is right there in the front. I went and, you know, our food ain’t the best here. It’s not very good fruit. For this program, if we want really good fruit we have to go to Rapid (120 miles one way) and buy it at Wal-Mart, and you go for quantities.” Some of the research Pickering Sherman has done at the Pine Ridge Reservation looks at the coping strategies people use to maintain food security on a daily basis. These are very dynamic households, she noted. “Every aspect of economic life of households on a reservation is constantly moving—household composition, whether you’re in or out of wage work, what kinds of resources you’re bringing to bear, how you’re responding to short-term and long-term health conditions. You really miss the ball when you try to annualize any of these kinds of measures.” A survey developed in concert with community members asked whether there was a time in the past year when the person being surveyed did not have enough food. For the 300 participants on the Pine Ridge Reservation, half said yes. Most pointed to economic hardships as the reason they did not have enough food. Thirty-two percent mentioned the expectation of sharing, which also occurs with borrowed money. “For Lakota people it’s considered culturally shameful to be a borrower, but it’s considered a good thing to be generous, so people will report what they gave or what they loaned to other people, but will underreport what they received or whom they borrowed from.” Food Assistance Programs Special food access programs occur on reservations. The Food Distribu- tion Program on Indian Reservations (FDPIR), started in 1977 as one of the Food Stamp Act renewal programs, has a critical influence on nutrition availability and affordability. “The reach of this commodities program is tremendous.” Pickering Sherman’s research has found a strong association between poverty and food insecurity. Many social and cultural circumstances sur- round the consumption and distribution of food. Yet programs such as FDPIR and SNAP focus on individuals or household units. “We need to think about community-based measures for understanding food access and food insecurity,” Pickering Sherman said. When asked about food sharing, for example, 91 percent of the respondents said that they share food with people not living in their household, so a community-level orientation for

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61 SENTINEL POPULATIONS food research is necessary. As one person said, “Everyone shares food here. It’s a Lakota trait. We share with whoever needs it. It’s a tradition that when someone comes into the house, you’re supposed to feed them.” Another respondent said, “No one has ever starved to death, because of the kinship system. Everyone has somewhere to go. Even strangers are treated as kin.” The U.S. Department of Agriculture (USDA) has tremendous potential to improve food security and the relationship with health on reservations, according to Pickering Sherman. The FDPIR and SNAP programs together represent 45 percent of the sources of food for reservation residents in Pine Ridge. In contrast, only 3 percent of the total food consumed is wild food, although 65 percent of households still hunt, fish, and gather wild plants. The Lakota people often mention the idea of restoring access to wild plants instead of using land for other purposes, such as leasing it for cattle production. Many households prefer to use SNAP rather than FDPIR, in part be- cause it is more flexible. About 58 percent of households use SNAP, and 41 percent use FDPIR. Also, some people suspect that the food provided by FDPIR cause diabetes, though there is no research substantiating such an association. The reduction of TANF (Temporary Assistance for Needy Families) benefit levels has caused confusion around SNAP. As people stay away from TANF, more pressure is being put on limited food dollars. The FDPIR program avoids some of these problems by providing foods that can be shared. A Holistic Approach Finally, Pickering Sherman said that people need places to engage in physical activity to help control weight. “I want to make a pitch for a ho- listic approach. When you link food security, health, physical activity, and economic (and cultural) revitalization, then you can start coming up with community-based solutions to food problems.” RURAL POPULATIONS In the United States there are two primary definitions of rural, said Christine Olson, professor in the Division of Nutritional Sciences at Cornell University. Using the definitions adopted for the 2000 Census of “rural” as open country and settlements less than 2,500 people, about 21 percent of the U.S. population was classified as rural in 2000. Nonmetropolitan areas, in contrast, are counties outside the boundaries of metropolitan areas. Using that definition, about 17 percent of the U.S. population lived in nonmetropolitan counties. There are 2,052 nonmetropolitan counties in

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62 HUNGER AND OBESITY the United States (Figure 4-3). Seventy-five percent of the land area in the United States today is nonmetropolitan. The low population density in rural areas means there are fewer ser- vices, and the services might be of lower quality. This is particularly true in the area of health, including mental health. “You might not have an M.D. psychiatrist within 200 miles of where you live in a rural community. You might get your primary health care related to mental health from a family physician.” Also, having a long distance to travel to services may influence the cost of those services or the adherence to treatment. The population in rural areas has a different composition than the population in urban areas. The population is older, and a higher propor- tion of people have disabilities. In self-rated health measures that are done in many surveys, rural residents are more likely to rate their health as poor than are urban residents. A smaller proportion of rural residents have gone to college. About 16 percent of the people in nonmetropolitan areas have 4-year college degrees, compared with about 27 percent in metropolitan counties. Metro (1,090 counties) Nonmetro (2,052 counties) FIGURE 4-3 Nonmetropolitan counties constitute 75 percent of the land area of the United States and contain about 20 percent of the U.S. population. 4-3 replace type.eps SOURCE: ERS, 2007. See http://www.ers.usda.gov/briefing/rurality/whatisrural/ (accessed January 10, 2011).

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63 SENTINEL POPULATIONS Underemployment and unemployment are more common in rural areas. Farming is no longer the primary occupation among rural residents. For people who live in nonmetropolitan counties, nonfarm employment accounts for 61 percent of total income. At the same time, wages in non- metropolitan areas are only about 60 percent of those in metropolitan ar- eas for a similar job. The cost of living can be lower outside metropolitan areas, but the wage differential has been getting bigger rather than smaller. Poverty rates are higher in nonmetropolitan areas than metropolitan areas. Using 2008 data, food insecurity among all households is slightly lower in nonmetropolitan areas (14.2 percent) than in metropolitan areas (14.7 percent) (Nord et al., 2009). Yet using the same data, nonmetropolitan households with children are more likely to be food insecure (22 percent) than households with children in metropolitan areas (20.8 percent). The prevalence of obesity (defined as a BMI ≥ 30) is higher among rural adults (23 percent) than urban adults (20.5 percent) (Jackson et al., 2005). When childhood overweight is defined as a BMI for age and sex above the 95th percentile, rural children (ages 10-17 years) are more likely to be overweight than urban children (Liu et al., 2008). Thus, using the data presented, both food insecurity and obesity are more common in nonmetropolitan than metropolitan areas among households with children. Research Findings Olson has done much of her work in the area surrounding Ithaca, in upstate New York. In a longitudinal study of 28 rural households below 200 percent of the federal poverty line and having at least one child less than the age of 13, one observation that comes out “loud and clear,” said Olson, is that adults restrain their eating and divert food to their children (Bove and Olson, 2006). According to a quotation from Eliza, “I don’t like to waste food, so sometimes I’ll find myself eating what the kids left over on their plates. . . . When things are low you don’t think about sitting down and having that complete meal.” Or as Therica said, “I go hungry for like 2 days and then I’ll eat. . . . ’Cause I normally don’t eat, I let the kids eat, and then I go for 2 days without eating and then when I do eat, it’s big meals that I eat.” This is not healthful in terms of avoiding obesity in the long run, Olson said. Adults in Olson’s survey also consume large quantities of sugar-sweetened beverages to cope with eating few solid foods. “I can’t tell you how many women told us, ‘I buy a 2-liter bottle of sugared soda for 99 cents, and that’s what I consume for the day when things really get tight.’ Or they go to work—coffee is free at work—and drink coffee all day with two sugars and cream.”

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64 HUNGER AND OBESITY After a period of deprivation, when the check comes in or they have gone shopping, people can eat much more. One woman described such a period as being like Christmas because the household had cookies. Emo- tional eating as a response to stress, including the stress of food insecurity, was also common in the sample. Women described such eating as “bing- ing.” There also was an association between this emotional eating pattern and weight: 74 percent of overweight or obese women report binging, compared with only 44 percent of the normal-weight women. The only underweight woman in the sample reported that she had the opposite reac- tion to stress and did not eat. A longitudinal study that followed women from early in their pregnan- cies to 2 years’ postpartum provided a way to track food insecurity, body weight, and weight gain over time (Olson and Strawderman, 2008). Being obese early in pregnancy was associated with being food insecure 2 years after childbirth, but food insecurity in early pregnancy was not associated with obesity 2 years after childbirth. The interaction of initial obesity and food insecurity was strongly related to major weight gain over time. Based on this result, Olson and her colleagues looked for a common element that predicts both food insecurity and increased risk of weight gain. In a sepa- rate study of the consequences of growing up poor, there was an association between childhood socioeconomic status and being overweight or obese in adulthood (Olson et al., 2007). Olson and her colleagues looked at several mechanisms behind this observation, and an important one that emerged is overeating as a generalized response to negative emotions. In poor families, persistence of food insecurity is common. Olson said that more than half of the families with low food security in her survey re- mained there 1 year later. Among the factors that constrain becoming food secure are chronic health conditions and having depressive symptoms. Fac- tors that support becoming food secure are having more than a high school education and 2 years of employment prior to the time being sampled. Numerous studies have found a positive relationship between food insecurity and obesity in adult women but not men, said Olson. Few studies have explored in depth any of the possible mediating mechanisms, but suspected mediators include overconsumption of energy-dense, low- nutrient foods; decreased consumption of fruits and vegetables and associ- ated nutrients; and disrupted eating patterns and feelings of deprivation. In rural populations, a long-term history of poverty and food insecurity makes it challenging to achieve food security and healthful body weight in adulthood. The relationship between food insecurity and obesity is likely bidirectional. Obesity may increase the risk of becoming food insecure. Food insecurity may make it harder to lose weight. In addition, lack of quality mental health services and health promotion programs is a barrier to solving the problems of food insecurity and obesity in rural areas.

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65 SENTINEL POPULATIONS COMMON THEMES In the final talk of the session on sentinel populations, Valerie Tarasuk, professor in the Department of Nutritional Sciences at the University of Toronto, highlighted several key issues. All of the talks on sentinel popula- tions brought to life the hard statistics of poverty and obesity among these groups while also revealing the complexity of these conditions. The depth and persistence of poverty, the marginalization that comes with those con- ditions, the racism and discrimination these groups face, and their inability to access services are common threads across sentinel populations, even though each context is multifaceted and unique. At the individual level, food access and food consumption patterns are rooted in issues of profound poverty, but they also reflect variations in stress and in physical activity. In particular, Tarasuk affirmed that obesity is a product of both energy intake and energy expenditures, and both have to be examined to understand the problem. The complexity of these relationships is one reason why it is so dif- ficult to delineate a relationship between food insecurity and obesity, said Tarasuk. This complexity also has implications for future research. First, it is important to focus on the life experiences of food insecurity starting in the womb. Stress and nutritional deprivation are obvious aspects of these experiences, but life history encompasses much more, including food insecurity within households in general. A second research topic is the persistence of food insecurity, which takes a different toll on health and well-being. The measure of food insecurity used today does not go beyond 12 months, but body weights are attained and change over decades. Obesity is a much more widespread problem than food insecurity, Tarasuk observed. About two-thirds of American adults are overweight or obese, and one-third of American children are. Even if every food-insecure person in the country were to lose weight, many Americans would still be overweight or obese. As a consequence, all Americans have a baseline risk factor driven by sedentary lifestyles and suboptimal diets and food supplies. Finding measures of individual susceptibility within that baseline can be difficult. “That’s a fundamental epidemiological problem,” she said. “We don’t have enough variants in the population, because everybody has a baseline risk factor.” The possibility of a link between food insecurity and obesity is still a useful question, but Tarausk said that broader issues also need to be ex- amined. A meeting focused on obesity would treat food insecurity as just a minor factor because the former is so much more prevalent than the latter. At the same time, food insecurity is linked to publicly supported food as- sistance programs, which can make it a politically freighted issue.

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66 HUNGER AND OBESITY GROUP DISCUSSION Moderator: Mariana Chilton During the group discussion period, points raised by participants included the following: Obesity as a Contributing Factor to Food Insecurity Christine Olson raised the issue of obesity being a contributing factor to food insecurity rather than the other way around. She noted that obe- sity can be a stigmatizing condition in rural communities. “The kinds of jobs that lower-income women can get are in the service sector, and how you look—if you have good teeth, if you have a pleasing body shape—is important to being effective as you’re standing behind the desk at the local hotel, which might be the kind of service job you could get.” In this case, the link between food insecurity and obesity is not through a nutritional pathway but through an economic pathway. Tarasuk noted that the same argument can be made from the data showing that obesity declines with income and wealth, though she added that the widespread prevalence of obesity in society might be expected to reduce the stigma associated with being overweight or obese. However, Nicolas Stettler pointed to data showing that the stigma attached to obesity for children has gotten worse over time. Craig Gundersen speculated about the negative consequences of tying food insecurity too closely to obesity. For example, some policy makers might be tempted to link food assistance programs to obesity and conclude that such programs should be curtailed to reduce obesity. Another partici- pant echoed this concern, saying that she once heard a local official raise doubts about the existence of food insecurity and hunger based on the rea- soning that if those phenomena actually existed, then people wouldn’t be overweight and obese. Quandt agreed that members of the general popula- tion can use a link as “an avenue for discrimination and racism.” Native American Populations In response to a question about whether Native Americans on reserva- tions exhibit differences in food insecurity and obesity from Native Ameri- cans elsewhere, Pickering Sherman observed that Native Americans living in cities are very diverse both genetically and culturally. “The one thing that they have most in common genetically is white ancestry—what are you re- ally able to glean from that?”

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67 SENTINEL POPULATIONS Obesity and Housing Values Adam Drewnowski pointed to a study in Washington State that looked at the link between obesity and the value of the homes in which people live. This gives a much broader range of distinctions, since the housing values used in their study ranged from $100,000 to $4 million. Just within Seattle, this study found disparities of sixfold in obesity rates. “We had some [groups] with 5 percent obesity and others with 35 percent obesity.” These distinctions are most obvious for women. “If you are a woman, the best thing to do is own your house and make sure it’s worth more than a million dollars, and the obesity rates go way down.” Obesity and Diet Quality Tarasuk raised the issue of the link between obesity and diet quality, observing that the differences in obesity between groups of people with higher- and lower-quality diets are less than would be expected (Tarasuk et al., 2007). Role for Emergency Food Networks Elizabeth Campbell with the University of California at Berkeley At- kins Center for Weight and Health pointed to the role of emergency food networks in combating food insecurity. In particular, public-private part- nerships can be quite effective in fighting food insecurity. The relationship between the two may not be well documented now, but this solution should not be overlooked. REFERENCES Bove, C. F., and C. M. Olson. 2006. Obesity in low-income rural women: Qualitative insights about physical activity and eating patterns. Women and Health 44(1):57-78. Bronte-Tinkew, J., M. Zaslow, R. Capps, A. Horowitz, and M. McNamara. 2007. Food inse- curity works through depression, parenting, and infant feeding to influence overweight and health in toddlers. Journal of Nutrition 137(9):2160-2165. ERS (Economic Research Service). 2007. Measuring rurality: What is rural? http://www.ers. usda.gov/briefing/rurality/whatisrural/ (accessed November 2010). Gilbert, M. E., R. MacPhail, J. Baldwin, V. C. Moser, and N. Chernoff. 2010. Moderate de- velopmental undernutrition: Impact on growth and cognitive function in youth and old age. Neurotoxicology and Teratology 32(3):362-372. Guo, S. S., W. Wu, W. C. Chumlea, and A. F. Roche. 2002. Predicting overweight and obesity in adulthood from body mass index values in childhood and adolescence. American Journal of Clinical Nutrition 76(3):653-658. IOM/NRC (Institute of Medicine and National Research Council). 2009a. Weight gain during pregnancy: Reexamining the guidelines. Washington, DC: The National Academies Press.

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68 HUNGER AND OBESITY IOM/NRC. 2009b. The public health effects of food deserts: Workshop summary. Washington, DC: The National Academies Press. Jackson, J. E., M. P. Doescher, A. F. Jerant, and L. G. Hart. 2005. A national study of obesity prevalence and trends by type of rural county. Journal of Rural Health 21(2):140-148. Kalil, A., and J. H. Chen. 2008. Mothers’ citizenship status and household food insecurity among low-income children of immigrants. New directions for child and adolescent development 2008(121):43-62. Kasper, J., S. K. Gupta, P. Tran, J. T. Cook, and A. F. Meyers. 2000. Hunger in legal immigrants in California, Texas, and Illinois. American Journal of Public Health 90(10):1629-1633. Larson, N., and M. Story. 2010. Food insecurity and risk for obesity among children and families: Is there a relationship? A research synthesis. Princeton, NJ, and Minneapolis, MN: Robert Wood Johnson Foundation Healthy Eating Research. Liu, J., K. J. Bennett, N. Harun, and J. C. Probst. 2008. Urban-rural differences in overweight status and physical inactivity among US children aged 10-17 years. Journal of Rural Health 24(4):407-415. Lucas, A. 2005. Long-term programming effects of early nutrition: Implications for the pre- term infant. Journal of Perinatology 25(2 SUPPL.). Martin, J. A., B. E. Hamilton, P. D. Sutton, S. J. Ventura, F. Menacker, S. Kirmeyer, and T. J. Mathews. 2009. Births: Final data for 2006. National Vital Statistics Reports 57(7). Martin, K. S., B. L. Rogers, J. T. Cook, and H. M. Joseph. 2004. Social capital is associated with decreased risk of hunger. Social Science and Medicine 58(12):2645-2654. Nord, M., M. Andrews, and S. Carlson. 2009. Household food security in the United States, 2008. Economic Research Report No. 83. Washington, DC: Economic Research Service. Ogden, C. L., K. M. Flegal, M. D. Carroll, and C. L. Johnson. 2002. Prevalence and trends in overweight among US children and adolescents, 1999-2000. Journal of the American Medical Association 288(14):1728-1732. Ogden, C. L., M. D. Carroll, L. R. Curtin, M. M. Lamb, and K. M. Flegal. 2010. Prevalence of high body mass index in U.S. children and adolescents, 2007-2008. Journal of the American Medical Association 303(3):242-249. Oken, E., and M. W. Gillman. 2003. Fetal origins of obesity. Obesity Research 11(4): 496-506. Olson, C. M., and M. S. Strawderman. 2008. The relationship between food insecurity and obesity in rural childbearing women. Journal of Rural Health 24(1):60-66. Olson, C. M., C. F. Bove, and E. O. Miller. 2007. Growing up poor: Long-term implications for eating patterns and body weight. Appetite 49(1):198-207. Pew Hispanic Center. 2010. Statistical portrait of the foreign-born population in the United States, 2008. Table 12. Washington, DC: Pew Hispanic Center. Quandt, S. A., J. I. Shoaf, J. Tapia, M. Hernández-Pelletier, H. M. Clark, and T. A. Arcury. 2006. Experiences of Latino immigrant families in North Carolina help explain elevated levels of food insecurity and hunger. Journal of Nutrition 136(10):2638-2644. Rosas, L. G., K. Harley, L. C. H. Fernald, S. Guendelman, F. Mejia, L. M. Neufeld, and B. Eskenazi. 2009. Dietary associations of household food insecurity among children of Mexican descent: Results of a binational study. Journal of the American Dietetic As- sociation 109(12):2001-2009. Stettler, N., S. K. Kumanyika, S. H. Katz, B. S. Zemel, and V. A. Stallings. 2003. Rapid weight gain during infancy and obesity in young adulthood in a cohort of African Americans. American Journal of Clinical Nutrition 77(6):1374-1378.

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69 SENTINEL POPULATIONS Tarasuk, V., L. McIntyre, and J. Li. 2007. Low-income women’s dietary intakes are sensitive to the depletion of household resources in one month. Journal of Nutrition 137(8): 1980-1987. Van Hook, J., K. S. Balistreri, and E. Baker. 2009. Moving to the land of milk and cook- ies: Obesity among the children of immigrants. Washington, DC: Migration Policy Institute. Whitaker, R. C., J. A. Wright, M. S. Pepe, K. D. Seidel, and W. H. Dietz. 1997. Predicting obesity in young adulthood from childhood and parental obesity. New England Journal of Medicine 337(13):869-873.

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