Physical Activity and Weight
Controlling weight through proper nutrition and regular physical activity is an important part of a healthy lifestyle. Lack of exercise and being overweight are risk factors for serious illnesses such as coronary heart disease, hypertension and diabetes, and contribute to premature death.
• Overweight is defined as having a Body Mass Index (BMI) that is greater than or equal to 25 and less than 30, and obese is a BMI of 30 or more. (figure 1) The BMI is the ratio of weight to height.
• Over the last 20 years, the proportion of King County adults who were either overweight or obese has increased to 55.5% in 2007. In 2007, the combined percent of overweight and obese adults in Washington State was 62.1% and 63.0% in the nation (data not shown).
• The percent of King County adults who are obese continues to increase while the percent of overweight adults has remained level in the past 10 years. In 1997, 34.4% of adults were overweight and 12.6% were obese. In 2007, the percent of overweight adults was unchanged (34.3%), but the percent of obese adults had risen to 21.2%.
• The combined percent of overweight and obese adults has increased in each of the four regions since 1994, the first year of data available by region (data not shown).
• From 2005-2007, 34.6% of King County adults were overweight and 20.0% were obese. (figure 2) The proportion of adults who were obese in North Region and East Region was similar to King County. Obesity rates were highest in South Region—higher than each of the other regions and King County as a whole. Seattle had the lowest percentage of obese adults.• Obesity rates in King County increased with age until age 65 when the rate declined.
• African Americans and American Indian/Alaska Natives were more likely to be obese than whites and Asians. (figure 3) Asians were least likely to be obese. Obesity rates among Hispanic/Latinos was similar to whites.
• Averaging data over 2005-2007, those in the highest income category were less likely to be obese than those earning less income, although this difference was not statistically significant in each case. While other research has shown a strong association between lower incomes and higher obesity rates, this correlation is not seen in King County. Significant differences in obesity rates by income group are not consistent over time in King County.
• Persons with the highest educational achievement (college graduates) were less likely to be obese.
• Local data by gender are not reported here. While national survey data that are based on physical measurement indicate that adult men are more likely to be overweight or obese than women, local survey data are based on self-report only and result in underestimations of weight.
• An adult has met the recommended level of physical activity if he or she reports having at least 30 minutes of moderate-intensity physical activity at least 5 days per week, or at least 20 minutes of vigorousintensity physical activity at least 3 days a week.
• On average, for years 2003, 2005 and 2006, 55.4% of King County adults reported meeting the recommended level of physical activity. (figure 4) Since 2001, the first year this question was asked on the survey reported here, the percent of adults meeting physical activity recommendations has not changed (some data not shown).
• The percentage of adults who met the recommended level of physical activity was lowest in South Region and highest in Seattle. No significant differences occurred between other areas.
• In 2007, 23.0% of Americans, nationwide, reported that they had not participated in any physical activity in the preceding month. This compares with 17.6% in Washington State and 15.9% in King County (data not shown).
• Persons ages 18 to 24 were more likely than those over the age of 44 to meet the recommended level of physical activity.
• 57.7% of whites met the recommended level of physical activity.(figure 5) This percentage is higher than any other race/ethnicity group except Native Hawaiians and Other Pacific Islanders. African Americans, American Indian/Alaska Natives, Asians and Hispanic/ Latinos were less likely to meet recommendations.
• Men and women met the recommended level of moderate/ vigorous physical activity in equal proportions.
• The likelihood of meeting physical activity recommendations increased with income. 60.4% of those with incomes of $50,000 or more met recommendations, compared to 47.5% of those with incomes less than $15,000.
• As education increased, so did the likelihood that recommended levels of physical activity were met. 59.4% of college graduates met recommended levels while only 38.9% of those without a high school degree met the standard.
• A Washington State survey asks youth in grades 8, 10, and 12 to report their physical activity levels and body weight. (figure 6) Youth are overweight if their BMI is greater than the 95th percentile on gender-specific BMI-for-age growth charts. Youth are at-risk of overweight if the BMI is between the 85th and 95th percentiles.
• In 2006, 9.0% of King County youth in grades 8, 10 and 12 were overweight and 13.3% were at risk of becoming overweight. Youth in East Region and North Region were less likely to be overweight or at-risk of becoming overweight and South Region youth were more likely, compared to King County overall. Seattle youth were similar to the County as a whole.
• Nationally, 13.1% of youth in grades 9 through 12 were overweight and 15.7% were at risk of overweight in 2005 (data not shown).
• African American (14.1%), American Indian/Alaska Native (14.9%) Hispanic/Latino (12.9%) Native Hawaiian and Other Pacific Islander (23.7%), and multiracial (11.4%) youth were more likely to be overweight than whites (7.0%) and Asians (6.9%). Similar patterns by race/ethnicity are seen for youth at risk of overweight (data not shown).
• Physical activity recommendations for youth are at least 60 minutes of activity on 5 or more days per week.
• In 2006, 39.1% of youth in grades 8, 10, and 12 met the guidelines for physical activity. (figure 7) Seattle youth were least likely to meet these recommendations. Youth in East Region were more likely to meet physical activity recommendations than youth in other regions except North Region.
• Nationally, 35.8% of youth in grades 9 through 12 met recommended levels of physical activity in 2005 (data not shown).
• In 2006 in King County, 8th, 10th, and 12th grade males (45.6%) were more likely to meet physical activity recommendations than females (32.2%) (data not shown).
• Asian (29.1%), Hispanic/Latino (29.9%), and multiracial (35.3%) youth were least likely to meet recommendations for physical activity. White (43.2%) youth were more likely than King County overall to meet recommendations. African American (38.9%), American Indian/Alaska Native (42.6%) and Native Hawaiian and Other Pacific Islander (39.0%) youth were similar to King County overall (data not shown).
Data Source, Definitions, and Limitations
Data on adult physical activity and weight are from the 2007 Washington State and national Behavioral Risk Factor Surveillance System (BRFSS). The BRFSS is a random telephone interview survey of non-institutionalized adults ages 18 and older that has been conducted in King County every year since 1987. Starting in 2003, the BRFSS was administered in English and Spanish. The question on physical activity level (how long and how many times per week) has been included since 2001 and was asked again in 2003, 2005, and 2006. The question on any physical activity in the previous month is asked every year. The limitations of an English-and-Spanish-only telephone survey include the following: a) people who do not have a land line telephone or who do not speak English or Spanish are excluded, and b) people who have less education and lower incomes are underrepresented.
Local data on youth physical activity and weight are from the 2006 Washington State Healthy Youth Survey. National data are from the 2005 National Youth Risk Behavior Survey.
