By George Vaillant, Next Avenue Contributor

If the child really is father to the man, then it's reasonable to ask: Why is that true?

This is not a simple question. But research from the Harvard Study of Adult Development allowed me to link childhood environments with men's lives in old age. The project, commonly known as the Harvard Grant Study, is the longest longitudinal study of human development ever undertaken. Begun in 1938, it has charted the emotional and physical growth of more than 200 men, starting in their undergraduate days at Harvard University.

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For the study, research associates assessed the childhoods of 268 Harvard sophomores and, separately, 456 disadvantaged inner-city youth. At least two independent raters, blind to the men's identities, reviewed each subject's answers to questions about their childhoods. In all cases parents were interviewed, too. The raters were kept ignorant of the fate of the men after adolescence. Rater reliability was excellent.

The goal was to use the assessments to answer these questions:

  • Was the home atmosphere warm and stable?
  • Was the boy's relationship with his mother (and, separately, his father) warm and encouraging, conducive to autonomy and supportive of initiative and self-esteem?
  • Was the boy close to at least one sibling?

Researchers discovered that wealth and status, to the extent that they correlated with successful aging, were not predicted by social privilege in youth, but instead by childhoods experienced as warm and intimate.

Upending Expectations

There were other surprises as well. For example, among the college men, achievement of high military rank in World War II correlated more highly with a warm childhood than with social class, athletic success or intelligence. For the 456 inner-city men, none of whose parents were wealthy, warm childhoods and friendships were best the predictors of high income.

Equally important, what went wrong in childhood predicted future income and social class less robustly than childhood strengths. The early study staff noted that neither strict nor liberal toilet training exerted any significant effect on future personality.

Another faulty assumption, based on retrospective "evidence," is that alcoholism is "caused" by an unhappy childhood. Data from our inner-city sample suggests that alcoholism is caused more by heredity than environment. An alcoholic parent appears in the childhoods of many alcoholics, leading to a miserable upbringing as well as future alcoholism. However, miserable childhoods without a biological alcoholic parent do not lead to alcoholism.

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The college men in the bottom and top fifths of the study's scale of childhood warmth were termed the Loveless and the Cherished. By age 50, half of the Cherished, but only an eighth of the Loveless, had made excellent adjustments to adulthood. By the time the men were 70, only a seventh of the Cherished, but fully half the Loveless, had at one time been diagnosed as mentally ill, under which rubric we included serious depression, drug or alcohol abuse or a need for extended psychiatric care (more than 100 visits) or hospitalization.

The Loveless were five times as likely as the Cherished to be unusually anxious. They took more prescription drugs of all kinds and were twice as likely to seek medical attention for minor physical complaints. Warm childhoods were often followed by heavy smoking, alcohol abuse or regular tranquilizer use, but bleak childhoods were often associated with all three.

Unhappy Childhood and Lonely Old Age

The cruelest aspect of a bleak childhood was its correlation with friendlessness at the end of life. The Cherished were five times more likely to be rich in friendships and other social supports at 70 than the Loveless, who often trusted neither the universe nor their emotions and remained essentially friendless for much of their lives.