Adult American women, on average, stand about 5 feet, 3 inches, according to data collected by the Centers for Disease Control and Prevention between 2007 and 2010 and published in 2012. The average height for women varied according to ethnicity and a woman's height decreased gradually as she turned 40 and beyond. A woman's genetics played a major role in her height, while her nutrition also contributed.
According to the CDC's 2012 study, the average height for an American woman over the age of 20 was 63.8 inches, which is slightly taller than 5 feet, 3 inches. The study data indicates that, on average, women had that tallest average height between the ages of 30 and 39. Between these ages, the average woman was 64.3 inches, which is about 5 feet, 3.5 inches.
Non-Hispanic white women and non-Hispanic black women are slightly taller than the American average. Women over the age of 20 in each demographic had an average height of 64.2 inches, which is 5 feet, 3.5 inches. Hispanic women over the age of 20 were more than an inch shorter than the national average. On average, Hispanic women over the age of 20 stood 61.9 inches, which is 5 feet, 1.5 inches.
On average, American women, regardless of ethnicity, experience an increase in height through their 20s and into their 30s, but begin to experience a decrease in their height from their 40s and onward. The average woman who stood 64.3 inches in her 30s stood 64.2 inches in her 40s, 63.9 inches in her 50s, 63.6 inches in her 60s, 62.6 inches in her 70s and 61.4 inches over the age of 80.
A mother who tells her children to eat their vegetables to grow tall is partially accurate, but nutrition doesn't influence height as much as genetics. A 2006 article in Scientific American magazine reports that your genetics influence your height by as little as 60 percent and as much as 80 percent. The other 20 to 40 percent, the magazine reports, is the result of issues such as nutrition.