A study started by Dr Terman in 1923 followed 1500 children. Two of his
graduate students continued the study after his death and recently published
a book on their results, The book is "The Longevity Project" by Dr. Friedman
and Leslie Martin. The authors found that:
The long-term health effects of parental divorce were often devastating--it was a risky circumstance that changed the pathways of many of the young Terman participants. Children from divorced families died almost five years earlier on average than children from intact families. In fact, parental divorce during childhood was the single strongest social predictor of early death, many years into the future.