You've likely heard it said, "Back in the good old days, people were much shorter. They were old at thirty-nine and dead at forty."
Maybe not. Such claims have circulated for years, but Carolyn Freeman Travers, Research Manager at Plimoth Plantation, disagrees. She also has evidence to back up her claims.
Travers says that the average height for an early 17th-century English man was approximately 5' 6". For 17th-century English women, it was just over 5'. While average heights in England remained virtually unchanged in the 17th and 18th centuries, American colonists grew taller. Averages for modern Americans are just over 5' 9" for men and about 5' 3¾" for women. The main reasons for this difference are improved nutrition, notably increased consumption of meat and milk, and antibiotics.
Excavations of cemeteries dating back to medieval England have provided a range of heights for both men and women and a mean average for both. Across the sites, the mean average height for males was about 5' 7'. For females, it was about 5' 1½". Excavations of graves dating to the American colonial period provide averages of 5' 7 ½" for males and 5' 2¼" for females.
By the time of the American Revolution, native-born Americans were nearly as tall as today's citizens.
You can read Carolyn Freeman Travers' full article at http://www.plimoth.org/learn/history/myth/fourfttwomyth.asp