It is written as if the reader is a time traveler going back to America in 1770. All the common place things that we would find really foul about life in that time period is discussed. It made me really happy to live when I do. I don't have to deal with rotten teeth and stinky, unwashed people (most of the time). This book certainly paints a rancid, unattractive picture of life during this time period.
I won't spoil it for you but it discusses the smells you would be inflicted with and what causes them, the bugs you would be dealing with, germs and diseases along with the medical practices used, and even what the people would have been wearing during these colonial years in American History.
I think the author may be right. I wouldn't be able to handle American life in 1770 knowing what I know now. My kids loved the grossness of this book and perhaps see things a lot differently when they "see" what life would have been like for the people of that day.