Here Are 10 Fascinating Findings from the Study
The Harvard Study of Adult Development began in 1938. It is sometimes also called ‘The Grant Study’.
This longitudinal prospective study aimed to identify predictors of healthy ageing in real-time.
For 79 years, it has examined the lives of 268 physically and mentally healthy Harvard college sophomores from 1939–1944 until their death, including eventual US President John F. Kennedy. It has also incorporated many of their offspring and 456 disadvantaged inner-city youths who grew up in Boston between 1940 to 1945.
Earlier this year, I listened to the 2012 audiobook by George Vaillant, titled “Triumphs of Experience.” He was the previous director of the study.
The primary research findings include:
1. “Alcoholism is a disorder of great destructive power.”
- Alcoholism precedes marital difficulties and is the leading cause of divorce, with 57% of divorces traced to alcoholism.
- Alcoholism can also lead to the later development of depression and neurosis.
- Alcoholism is the most significant predictor of early death alongside cigarette smoking.
2. “Above a certain level, intelligence doesn’t matter.”
- There is no significant difference in income earned by men with an IQ of 110–115 compared to men with an IQ higher than 150.
3. “Ageing liberals have more sex.”
- While political ideology has no significant impact on life satisfaction overall, most liberal men continue to have an active sex life into their 80s. In contrast, conservative men are likelier to cease having sex by 68.
4. “For good or ill, the effects of childhood last.”
- A warm childhood relationship with the mother predicts greater financial earnings later in life ($87,000 more than males who had uncaring mothers), greater effectiveness at work later in life, and a three times lower risk of dementia in old age.
- A warm childhood relationship with the father predicts lower rates of anxiety and pessimism during adulthood, increased life satisfaction later in life, reduced difficulties in letting others get close and greater enjoyment of vacations throughout life.
5. “It is not one thing for good or ill — social advantage, abusive parents, physical weakness — that determines how children adapt to life, but the quality of their total experience.”
- It means that what goes right during childhood matters much more than what goes wrong.
- If bad things happen, as long as they are outweighed by the good, you are likely to still turn out okay.
- “Bleak childhoods were not always associated with bleak marriages.”
- “Restorative marriages and maturing [psychological] defences” are “the soil out of which resilience and post-traumatic growth emerge.”
6. “People really can change, and people really can grow. So childhood need be neither destiny nor doom.”
7. “Even the death of a parent was relatively unimportant by the time the men were fifty. By age eighty, men who had lost parents when young were as mentally and physically healthy as men whose parents had lovingly watched them graduate from high school.”
8. “Prudence, forethought, willpower, and perseverance in junior high school were the best predictors of vocational success at age fifty.”
9. “All fifty-five Best Outcomes had gotten married relatively early and stayed married for most of their adult lives. Proportionately three times as many of the Best Adjusted men enjoyed lifelong happy marriages as the Worst.”
- The effect of marriage was even starker for the inner-city men of the Glueck Study: “two-thirds of the never-married were in the bottom fifth in overall social relations, 57% were in the bottom fifth in income, and the study raters classified 71% as mentally ill.”
- “It turned out that happy marriages after eighty were not associated either with warm childhoods or mature defences in early adulthood — that is, you don’t have to start ‘all grown up’ to end up solidly married.”
10. “It was the capacity for intimate relationships that predicted flourishing in all aspects of these men’s lives.” In other words, “Happiness is love. Full stop.”
- Spouses’ mutual dependence on each other was associated with happy and healthy marriages. For example, 76% of the men still alive at age eighty-five said their marriages were happy.
- “Most of the men who flourished found love before thirty, and that was why they flourished.”
See the latest director of the study Robert Waldinger talk about the key findings from the Harvard Study of Adult Development for more information. His TED talk has millions of views:
I hope you find these highly significant findings as fascinating as I do.
They also give us scientifically supported indicators of what to do if you want to live a happy, healthy, and long life.
Dr Damon Ashworth