Weird Things That Happen to Your Body After 40, Says Science Weird Things That Happen to Your Body After 40, Says Science A recent poll found that the average American considers 36 years-old to be the "perfect" age. Among the respondents, four in 10 even said they'd prefer to "freeze the clock" and stay in their late-thirties indefinitely. It all begs the question: Is turning the big four-oh really all that bad? Well, of course not. In fact, there's plenty of science to suggest that turning 40 may be one of the best things that will ever happen to you. According to one report published by the