Overweight and Obesity Epidemic in America – Part I:

Suggested Citation: Garko, M.G. (2010, October). Overweight and obesity in America – Part I: Disturbing statistics and trends. Health and Wellbeing Monthly. Retrieved (insert month, day, year), from www.letstalknutrition.com.

Overweight and Obesity Epidemic in America – Part I:
Prevalence and Trends Among Adults

Michael G. Garko, Ph.D.
Host – Let’s Talk Nutrition

Introduction

Obesity is among the most serious public health threats to American adults and children in the 21st century. According to a report supported in part by the National Institute on Aging (NIA) and submitted by Olshansky et al. (2005), obesity is a public health crisis which possibly threatens to decrease life expectancy in the United States by as much as five years, unless dramatic efforts are made to turn the tide of the rising rates of obesity among adults and children.

Olshansky et al. (2005) give the following ominous warning about the potential negative impact of the obesity epidemic on life expectancy: “Unless effective population-level interventions to reduce obesity are developed, the steady rise in life expectancy observed in the modern era may soon come to an end and the youth of today may, on average, live less healthy and possibly even shorter lives than their parents” (Olshansky, et al., 2005, p. 1143). They warn further that “if the negative effect of obesity on life expectancy continues to worsen, and current trends in prevalence suggest it will, then gains in health and longevity that have taken decades to achieve may be quickly reversed” (Olshansky, et al., 2005, p. 1143).

This is just one of the potential health consequences of the obesity epidemic undermining the health of Americans. Other health problems associated with obesity include coronary heart disease, stroke, high blood pressure, high cholesterol, type 2 diabetes, gallbladder disease, osteoarthritis, respiratory problems, cancer (e.g., endometrial, breast, prostate & colon cancer), insulin resistance and psychological problems, among others (see U.S. Department of Health and Human Services, 2010).

The October, 2010 issue of Health and Wellbeing Monthly (HWM) is the first in a series on Overweight and Obesity Epidemic in America. The focus in this issue of HWM will be on the disturbing statistics and trends in overweight and obesity among adults in the United States. Next month in HWM, Part II of Overweight and Obesity Epidemic in America will focus on children.

Overweight and Obesity Defined

The term “overweight” refers to an excessive amount of body weight, which can be constituted of muscle tissue, bone, adipose or fat tissue and water, while the term “obesity” refers to an excessive amount of adipose or fat tissue (see National Institute of Diabetes and Digestive and Kidney Diseases, 2010).

Body Mass Index

The statistics and trends reported below from the 2007–2008 National Health and Nutrition Examination Survey (NHANES). Body mass index (BMI) was used in the NHANES to determine who in the survey was overweight, obese or extremely obese. As a formula, BMI is expressed as weight in kilograms divided by height in meters squared (kg/m2). The BMI taxonomy is used quite often to classify overweight (BMI 25.0–29.9), obesity (BMI greater than or equal to 30.0), and extreme obesity (BMI greater than or equal to 40.0) (Ogden & Carroll, 2010).

Prevalence of Overweight, Obesity and Extreme Obesity Among Adults

According to the National Center for Health Statistics (NCHS) of the Centers for Disease Control and Prevention (CDC), the National Health and Nutrition Examination Survey (NHANES) revealed that in 2007-2008, when adjusting for age, an estimated 34.2% of American adults 20 years of age and older were overweight, while 33.8% were obese (Ogden & Carroll, 2010).

Prevalence of Overweight and Obesity Combined

The overall prevalence estimates for overweight and obesity when combined for adults 20 years of age and older (BMI  25) was a stunning 68.0% (Ogden & Carroll, 2010).  Another way to think about the overweight and obesity epidemic is that less than a third of adults (i.e., 31.6%) in the United States are at a healthy weight. Of the total percentage of healthy weight adults, 36.5% and 26.6% are women and men, respectively (see National Institute of Diabetes and Digestive and Kidney Diseases, 2010).

Gender Differences in Prevalence of Overweight and Obesity

Of the total percentage of adults 20 years of age and older who were obese or overweight (i.e., 68%), 64.1% and 72.3% of women and men were overweight or obese, respectively (Ogden & Carroll, 2010).

Gender Differences in Prevalence of Obesity

Of the total percentage of adults 20 years of age and older who were obese (i.e., 33.8%), 35.5% and 32.2% of women and men were obese, respectively. It is worth noting that 5.7% of all obese adults were extremely obese (Ogden & Carroll, 2010).

Trends in Overweight, Obesity and Extreme Obesity Among Adults

Data from the NHANES 2007–2008 for adults aged 20 and over show a trend increase in the prevalence of obesity occurring between the late 1980s to present day. The estimated age-adjusted prevalence for obesity moved upward from a previous level of 23% in NHANES III (1988–1994) to approximately 34% in NHANES 2007–2008 (Ogden & Carroll, 2010). See Table 1 and Figure 1 for overweight and obesity trends since 1988.

When going back further in time to examine overweight and obesity trends, NHANES data from 1960-1962 to 2007-2008 show that the prevalence of obesity among adults aged 20–74 more than doubled between 1976–1980 and 2007–2008, while the prevalence of overweight was stable during the same period (Ogden & Carroll, 2010).  See Table 2 and Figure 2 for trends since 1960.

Trends in Prevalence of Overweight and Obesity Among Women and Men

In terms of overweight and obesity trends among women and men, NHANES data between 1999–2000 and 2007–2008 show that there no significant change occurred among women. For men, however, NHANES data do show a significant linear increase between 1999–2000 and 2007–2008, with no change between 2003–2004 and 2007–2008 (Ogden & Carroll, 2010).  See Table 1 and Figure 1 for trends in obesity and overweight prevalence since 1988–1994.

Trends in Prevalence of Obesity Among Different Racial-Ethnic Groups

NHANES data reveal significant racial and ethnic disparities in adult obesity. See Table 3 for estimates in the prevalence for obesity by race/ethnicity for men and women since NHANES III (1988–1994) (Ogden & Carroll, 2010).

Trends in Prevalence of Male Obesity Among Different Racial-Ethnic Groups

NHANES data from 2007–2008 and 1988–1994 indicated no significant differences between racial and ethnic groups in the prevalence of obesity among men. However, the prevalence of obesity among men increased between 1988–1994 and 2007–2008 in the following ways:

• From 20.3% to 31.9% among non-Hispanic white men.
• From 21.1% to 37.3% among non-Hispanic black men.
• From 23.9% to 35.9% among Mexican-American men (Ogden & Carroll, 2010, p.1) See Figure 3.

Trends in Prevalence of Female Obesity Among Different Racial-Ethnic Groups

NHNES data indicated significant differences between racial and ethnic groups in the prevalence of obesity among women. In 2007-2008, “non-Hispanic black women (49.6%) were significantly more likely to be obese than non-Hispanic white women (33.0%)” and in a similar fashion “Mexican-American women (45.1%) were more likely to be obese than non-Hispanic white women (33.0%)” (Ogden & Carroll, 2010, p.1).

Going back to the period 1988-1994, a similar pattern of racial-ethnic disparity among women existed in that “22.9% of non-Hispanic white women, 38.3% of non-Hispanic black women, and 35.3% of Mexican-American women were obese” (Ogden & Carroll, 2010, p.1).

Trends in the prevalence of obesity among women of different racial-ethnic groups increased between 1988–1994 and 2007–2008 in the following ways:

• From 22.9% to 33.0% among non-Hispanic white women.
• From 38.2% to 49.6% among non-Hispanic black women.
• From 35.3% to 45.1% among Mexican-American women (Ogden & Carroll, 2010, p.2). See Figure 4.

Obesity and Mortality

Compared to those of healthy weight, obese individuals are at a significant increased risk of death from all causes. This increased risk of obese individuals dying varies by the specific cause of death. Cardiovascular disease accounts for most of the increased risk of dying, with more than 112,000 excess deaths of obese individuals attributable to cardiovascular disease. Further, it is estimated that there are more than 15,000 added deaths of obese individuals due to cancer and more than 35,000 added deaths of obese persons attributable to non-cancer, non-cardiovascular disease causes each year in the United States, compared to healthy-weight individuals (see Ogden & Carroll, 2010).

Conclusion

It is an understatement to say that overweight and obesity constitute an epidemic in the United States. In fact, together overweight and obesity pose one of the most serious health challenges facing Americans in the 21st century.  Stunningly, an estimated 68% of adults aged 20 and older are either overweight (34.2%) or obese (33.8%). Only 31.8% of adult 20 and older are at a healthy weight.

The prevalence and trend data from NHANES conducted over several decades reveal obesity to be a non-discriminating serial health killer of adult men and women. Furthermore, obesity threatens to reverse decades-worth of achievements in health and life expectancy.

In terms of who is at greater risk to become obese, there are more men than women aged 20 years and older who are obese. Compared to non-Hispanic White women, there are more non-Hispanic Black and Hispanic women who are obese. It is worth noting that there is a lower prevalence of obesity among Asian Americans than other racial and ethnic groups.

Notwithstanding gender and racial-ethnic differences, the prevalence of obesity has increased at a steady rate for men and women, all age groups, racial-ethnic groups, educational levels and smoking levels.

Perhaps what is most troublesome about the obesity epidemic is that it is not confined to just adults. Obesity is among the most serious, if not most serious health threat to American children in the 21st century. In the November, 2010 issue of Health and Wellbeing Monthly the health spotlight will be on the prevalence and trends of overweight and obesity among children.

Children are vital to creating a healthy and fit nation. The scientific data will reveal that the public health policy of creating and sustaining a healthy and fit nation is being undermined by an unprecedented increase in unhealthy and unfit overweight and obese children now suffering from adult diseases.

Suggested Citation: Garko, M.G. (2010, October). Overweight and obesity in America – Part I: Prevalence and trends among adults. Retrieved (insert month, day year), from www.letstalknutrition.com

Tables

Table 1. Age-adjusted prevalence of overweight, obesity, and extreme obesity among U.S. adults aged 20 and over
Sample size and weight status NHANES
1988-1994
NHANES
1999-2000
NHANES
2001-2002
NHANES
2003-2004
NHANES
2005-2006
NHANES
2007-2008
Sample (n) 16,679 4,117 4,413 4,431 4,356 5,555
Overweight
(25 ≤ BMI < 30)
33.1 34.0 35.1 34.1 32.7 34.2
Obese
(BMI ≥ 30)
22.9 30.5 30.6 32.2 34.3 33.8
Extremely obese (BMI ≥ 40) 2.9 4.7 5.1 4.8 5.9 5.7

NOTES: NHANES is National Health and Nutrition Examination Survey; BMI is body mass index. Age-adjusted by the direct method to the year 2000 U.S. Census Bureau estimates using the age groups 20-39, 40-59, and 60 years and over. Crude estimates (not age adjusted) for 2007-2008 are 34.4% overweight, 33.9% obese, and 5.7% extremely obese. Pregnant females were excluded from the analysis.

Source: Ogden, C.L. & Carroll, M.D. (2010).  Prevalence of overweight, obesity, and extreme obesity among adults: United States, trends 1976–1980 through 2007–2008. NCHS Health E-Stat. Hyattsville, MD:National Center for Health Statistics.

Table 2. Age-adjusted prevalence of overweight, obesity, and extreme obesity among U.S. adults aged 20-74
Sample size and weight status NHANES I
1960-1962
NHANES I
1971-1974
NHANES II
1976-1980
NHANES
III
1988-1994
NHANES
1999-2000
NHANES
2001-2002
NHANES
2003-2004
NHANES
2005-2006
NHANES
2007-2008
Sample (n) 6,126 12,911 11,765 14,468 3,603 3,916 3,756 3,835 4,881
Overweight
(25 ≤ BMI < 30)
31.5 32.3 32.1 32.7 33.6 34.4 33.4 32.2 33.6
Obese
(BMI ≥ 30)
13.4 14.5 15.0 23.2 30.9 31.3 32.9 35.1 34.3
Extremely obese
(BMI ≥ 40)
0.9 1.3 1.4 3.0 5.0 5.4 5.1 6.2 6.0

NOTES: NHES is National Health Examination Survey; NHANES is National Health and Nutrition Examination Survey; BMI is body mass index. Age-adjusted by the direct method to the year 2000 U.S. Census Bureau estimates using the age groups 20-39, 40-59, and 60-74 years. NHES included adults aged 18-79, and NHANES I and II did not include individuals over age 74, so trend estimates are based on ages 20-74. Pregnant females were excluded from the analysis.

Source: Ogden, C.L. & Carroll, M.D. (2010).  Prevalence of overweight, obesity, and extreme obesity among adults: United States, trends 1976–1980 through 2007–2008. NCHS Health E-Stat. Hyattsville, MD:National Center for Health Statistics.

Table 3. Prevalence of obesity among U.S. adults aged 20 and over, by sex and race/ethnicity, for selected years 1988-1994 through 2007-2008

Characteristic NHANES 1988-1994 NHANES
1999-2000
NHANES 2001-2002 NHANES 2003-2004 NHANES 2005-2006 NHANES 2007-2008
Men, All 20.2 27.5 27.8 31.1 33.3 32.2
Men, Non-Hispanic white 20.3 27.3 29.1 31.1 33.1 31.9
Men, Non-Hispanic black 21.1 28.1 27.9 34.0 37.2 37.3
Men, Mexican American 23.9 28.9 25.9 31.6 27.0 35.9
Women1, All 25.4 33.4 33.3 33.2 35.3 35.5
Women1, Non-Hispanic white 22.9 30.1 31.3 30.2 32.9 33.0
Women1, Non-Hispanic black 38.2 49.7 48.3 53.9 52.9 49.6
Women1, Mexican American 35.3 39.7 37.0 42.3 42.1 45.1

1 Excludes pregnant females.

NOTES: NHANES is National Health and Nutrition Examination Survey. Age-adjusted by the direct method to the year 2000 U.S. Census Bureau estimates using the age groups 20-39, 40-59, and 60 years and over. Obesity is defined as having a body mass index (BMI) greater than or equal to 30.

Source: Ogden, C.L. & Carroll, M.D. (2010).  Prevalence of overweight, obesity, and extreme obesity among adults: United States, trends 1976–1980 through 2007–2008. NCHS Health E-Stat. Hyattsville, MD:National Center for Health Statistics.

Figures

Source: Ogden, C.L. & Carroll, M.D. (2010).  Prevalence of overweight, obesity, and extreme obesity among adults: United States, trends 1976–1980 through 2007–2008. NCHS Health E-Stat. Hyattsville, MD:National Center for Health Statistics.

Source: Ogden, C.L. & Carroll, M.D. (2010).  Prevalence of overweight, obesity, and extreme obesity among adults: United States, trends 1976–1980 through 2007–2008. NCHS Health E-Stat. Hyattsville, MD:National Center for Health Statistics.

Source: Ogden, C.L. & Carroll, M.D. (2010).  Prevalence of overweight, obesity, and extreme obesity among adults: United States, trends 1976–1980 through 2007–2008. NCHS Health E-Stat. Hyattsville, MD:National Center for Health Statistics.

Source: Ogden, C.L. & Carroll, M.D. (2010).  Prevalence of overweight, obesity, and extreme obesity among adults: United States, trends 1976–1980 through 2007–2008. NCHS Health E-Stat. Hyattsville, MD:National Center for Health Statistics.

References

National Institute of Diabetes and Digestive and Kidney Diseases (2010). Overweight and obesity statistics. Retrieved September 25, 2010, from http://www.win.niddk.nih.gov/publications/PDFs/stat904z.pdf

Ogden, C.L. & Carroll, M.D. (2010).  Prevalence of overweight, obesity, and extreme obesity among adults: United States, trends 1976–1980 through 2007–2008. NCHS Health E-Stat. Hyattsville, MD: National Center for Health Statistics. Retrieved September 25, 2010, from http://www.cdc.gov/nchs/data/hestat/obesity_adult_07_08/obesity_adult_07_08.pdf

Olshansky, S.J., Passaro, D.J., Hershow, R.C., Layden, J.L., Carnes, B.A., Bordy, J., Hayflick, L., Butler, R.N., Allison, D.B. & Ludwig, D.S. (2005). A potential decline in life expectancy in the United States in the 21st Century. The New England Journal of Medicine, 352 (11), 1138-1145. Retrieved September 25, 2010, from http://www.nejm.org/doi/full/10.1056/NEJMsr043743

U.S. Department of Health and Human Services (2010). The surgeon general’s vision for a healthy and fit nation. Rockville, MD: U.S. Department of Health and Human Services, Office of the Surgeon General.

Wang, Y. & Beydoun, M.A. (2007). The obesity epidemic in the United States—Gender, age, socioeconomic, racial/ethnic, and geographic characteristics: A systematic review and meta-regression analysis. Epidemiologic Reviews, 29 (1), 6-28. Retrieved September 25, 2010 from http://epirev.oxfordjournals.org/content/29/1/6.full.pdf+html

Suggested Citation: Garko, M.G. (2010, October). Overweight and obesity in America – Part I: Disturbing statistics and trends. Health and Wellbeing Monthly. Retrieved (insert month, day, year), from www.letstalknutrition.com