Poor nutrition or underlying health conditions can sometimes cause a person to be underweight. Data from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) showed that an estimated 1.8% of U.S. adults are underweight. Between 1988-1994 and 2003-2006, a statistically significant decrease in the percentage of those underweight was found only among those aged 60 and over. In this age group, the percentage underweight was 2.3% in 1988-1994 and 1.2% in 2003-2006.
For more, visit http://www.cdc.gov/nchs/data/hestat/underweight_adults.htm.
Results from the 2003-2006 NHANES showed that about 3.3% of children and adolescents aged 2-19 years are underweight. Trends from 1971-1974 to 2003-2006 show that there has been an overall significant decrease in underweight children and adolescents, from 5.1% to 3.3%. Underweight significantly decreased from 5.8% to 2.8% among 2-5 year olds and from 5.3% to 2.7% among 6-11 year olds. Among adolescents aged 12-19, underweight decreased, although not significantly, from 4.7% to 3.8% during the same time period.
For more, visit http://www.cdc.gov/nchs/data/hestat/underweight_children.htm.