Love Is All You Need: Insights from the Grant Study

The Grant Study, which has tracked the lives of nearly 5,000 men for more than 75 years, showed that happiness and marital satisfaction are not contingent on financial success. Men who were divorced or widowed had a similar level of life satisfaction in their later years as those who never married.

The “what is the biggest predictor of an early death among the participants in the grant study” is a question that has been asked many times. The answer is that it was not one particular thing, but rather a combination of factors.

Old couple dancing at home with plants at the back.

Why do two guys with identical financial and educational origins occasionally follow drastically different courses in life?

Is it more significant for a man’s success in his relationships and job to be born or raised?

What physiological and psychological characteristics in a man’s youth determine his chances of living a long and prosperous life?

Researchers at Harvard Medical School launched a study in 1938 with the goal of answering these intriguing issues and determining what elements contribute to a “optimal” life. The research enlisted 268 sophomores from the university’s all-male classes of 1939-1944 and set out to investigate every element of their life for at least two decades. The males chosen were physically and mentally healthy, and were seen to have a good chance of realizing their potential and becoming successful adults. While many of them hailed from wealthy backgrounds, others were bright children who had been recruited from low-income homes and given full scholarships.

Participants agreed to have their lives probed extensively as part of the research. They were given physical exams and psychological evaluations; researchers interviewed their parents and three generations of relatives at their homes; the men filled out an extensive questionnaire every year about their health, habits, family, political views, career, and marriage; and the men were interviewed face-to-face every 10-15 years.

This study effort, known as the Grant Study, is still going strong more than 75 years later. It has since been extended many times, making it one of the world’s longest longitudinal studies. George Vaillant, the study’s director for decades, began working on the research when he was thirty-two years old and the participants were in their forties; now, Vaillant is nearing eighty years old, and the men are in their nineties. Participants are still filling out their yearly surveys, and Vaillant is still studying their responses.

Nothing like the Grant Study has ever been done before; as Vaillant puts it, it’s “one of the first vantage points the world has ever had on which to stand and gaze prospectively at a man’s life from eighteen to ninety.” The mounds of data accumulated over more than seven decades have become a gold mine for researchers looking into what elements present in a man’s earlier years best indicate whether he would be successful and happy in later life. Researchers at the study have been sifting through the data and reports in an effort to find these potential features. Some of the researchers’ initial assumptions did not play out, as Vaillant explains in The Triumphs of Experience, and the task of untangling questions of cause and association continues. Nonetheless, some key conclusions have emerged from the data, providing brightly lit guideposts to a life well lived.

Relationships and Their Importance

Vaillant devised a list of ten accomplishments to determine what factors predicted a man’s ability to become a successful, well-adjusted adult, including professional success and prominence, mental and physical health, a good marriage, supportive friendships, closeness to one’s children, the ability to enjoy work, love, and play, and a subjective level of happiness. He used the term “Decathlon of Flourishing” to describe how far each guy in the research had progressed through these “events” between the ages of 65 and 80. Vaillant next went back over the men’s personal histories to see what elements from earlier in their lives most accurately predicted their Decathlon result.


When Vaillant crunched the facts, he found no link between a man’s degree of thriving and his IQ, his physical type (mesomorph, ectomorph, endomorph), or his parents’ wealth and education level.

Relationships were one of the elements that loomed big and predicted all ten Decathlon events. The following items were included in the rubric:

  • A kind and supportive childhood
  • A mature “coping style” is one that is used to deal with a variety of situations (being able to roll with the punches, be patient with others, keep a sense of humor in the face of setbacks, delay gratification, etc.)
  • During college, overall “soundness” was assessed (resilient, warm personality, social, not overly sensitive)
  • Between the ages of 37 and 47, warm adult relationships exist (having close friends, maintaining contact with family, being active in social organizations)

Vaillant discovered that the men who scored highest in these categories throughout their adolescence and mid-life were the happiest, most successful, most well-adjusted in later life. This is the most significant conclusion of the Grant Study: “It was the ability for close connections that predicted thriving in all facets of these men’s life.”

The impact of personal relationships may be evident in a range of aspects of a man’s life, including his financial situation:

  • Men who had at least one excellent connection with a sibling as a child earned $51,000 more per year than men who had no siblings or had bad relationships with their siblings.
  • Those from stable households earned $66,000 more per year than men from unstable homes.
  • Those with loving moms earned $87,000 more than men with unsympathetic mothers.
  • The 58 guys who scored highest for warm connections earned over $150,000 more per year than the 31 men who scored lowest.

Keep in mind that all of these individuals had a Harvard degree before they joined the business. Also keep in mind that their parents’ socioeconomic condition had little bearing on their own future earnings.

Vaillant discovered particular impacts that arose from a man’s youth and the relative influence of his mother and father, in addition to discovering that warm interactions in general had a good impact on the men’s lives.

Childhood Experiences Have an Impact on a Man’s Life

Vintage family eating dinner on table.

“Woe to the guy whose heart has not learnt to hope, love, and trust in life when he was young.” Joseph Conrad (Joseph Conrad, Joseph Conrad, Joseph Conrad, Joseph Conrad, Joseph Con

In order to assess the impact of a man’s upbringing on his future possibilities, Vaillant graded the participants’ upbringing on the following criteria:

  • Was the environment at home welcoming and consistent?
  • Was the boy’s connection with his father warm and encouraging, supportive of initiative and self-esteem, and favorable to autonomy?
  • Was the boy’s connection with his mother warm and encouraging, supportive of initiative and self-esteem, and favorable to autonomy?
  • Would the rater have preferred to grow up in that family?
  • Was there at least one sibling in the boy’s life?

When the men’s lives were studied and compared to this set of criteria, it became evident that “the consequences of infancy, for good or evil, persist a long time.” A happy childhood was shown to be a much better predictor of a man’s success later in life, including his general happiness in his late seventies, than his parent’s social status or his own money. When the males who had the warmest childhoods (named “the Cherished”) are contrasted to those who had the coldest childhoods (designated “the Loveless”), the consequences are especially striking:


  • The Cherished were paid 50% more than the Loveless.
  • At the age of seventy, the Cherished were 5X more likely to have deep connections and warm social support.
  • The Loveless were 3.5 times more likely than the general population to be diagnosed with mental illness (which includes serious depression, abuse of drugs and alcohol, and need for extended psychiatric care)
  • The Loveless were 5X as likely to feel nervous than the rest of the population.
  • The Loveless were twice as likely to seek medical treatment for minor physical concerns and consumed more prescription medicines of all types.

A caring, supportive childhood seems to increase a man’s chances of success in his relationships and job, as well as protect him against future mental illness.

Independence and resiliency are developed via a loving childhood.

While parenting experts have worried in the past that a home filled with unconditional love and support would produce a young man who was too coddled and dependent, the Grant Study discovered that abundant familial love, when combined with an emphasis on autonomy and initiative, produced the most stoic (able to keep a stiff upper lip) and independent men. Such guys, according to Vaillant, had learnt to be at ease with their emotions and “placed their confidence in life, which allowed them the guts to go out and confront it.” The guys who had the poorest childhoods, on the other hand, were the most reliant and unable to take initiative.

Even when compared to the usually male goal of achieving military rank, the association maintained true. Since the Grant Study started at the start of WWII, researchers were naturally interested in determining which features of the men’s physical and psychological makeup would best predict their chances of becoming officers during the conflict. They discovered that the men’s rank at the time of release had nothing to do with their physical type, IQ, or the socioeconomic position of their parents. Instead, a loving upbringing and whether or not a guy had good ties with his mother and siblings were the strongest predictors of better rank. “Of the twenty-seven men with the happiest childhoods, twenty-four rose to the rank of first lieutenant, and four rose to the rank of major. Thirteen of the thirty guys who had the worst childhoods did not achieve first lieutenant, and none of them made majors.” “We don’t breed excellent officers; we don’t even construct them on the playing fields of Eton; we grow them in loving households,” Vaillant finishes.

What is important is what is done correctly rather than what is done incorrectly.

“It is not any one thing for good or ill—social advantage, abusive parents, physical weakness—that determines the way children adapt to life, but the quality of their total experience,” a corollary was discovered while studying the powerful impact a man’s childhood has on his prospects for health, happiness, and success. Basically, the Grant Study discovered that even if you had a lot of awful things happen to you throughout your childhood, if the positive things outnumber the bad, you’ll be OK. So, even if a guy had an absent father but a close connection with his mother and siblings, or if he had chilly parents but loving grandparents, his chances of future success were still excellent. According to Vaillant, the quality of one’s upbringing as a whole mattered more than any one aspect or set of circumstances.


The outcomes of a research conducted concurrently with the Grant Study elucidate this point. Because the Grant Study’s participants were not very varied, researchers started running the Gluek Study alongside it in 1940, which included 456 impoverished non-delinquent inner-city kids from the Boston region. Even though the family was poor, the father was on welfare, and the family had various other issues, boys who were loved by their moms, revered their fathers, and had strong friendships went on to become successful and acquire a better socioeconomic standing. This explains why guys who were up in poverty families yet went on to achieve success sometimes say things like, “Even though we were poor, we never recognized it as children since our parents made our home such a pleasant environment.”

“Even the death of a parent was relatively unimportant predictively by the time the men were fifty,” Vaillant continued, “and by the time they were eighty, men who had lost parents when they were young were as mentally and physically healthy as men whose parents had lovingly watched them graduate from high school.”

The Mother’s Influence

Vintage mother and sons at beach in swimsuits.

Not only did a man’s entire childhood experience have a significant effect on the remainder of his life, but so did his mother and father. According to the Grant Study, a man’s close connection with his mother was strongly related to his:

  • at work efficiency
  • greatest income in later life
  • Towards the conclusion of WWII, military rank
  • inclusion in Who’s Who in the World
  • In college, IQ
  • Scores on spoken tests
  • In college, you have a class rank.
  • Mental acuity at the age of 80

On the other hand, “a bad connection with his mother was very strongly, and quite shockingly, connected with dementia,” according to the study. Men who had a strained connection with their moms were three times as likely to develop dementia later in life.

Vintage mom posing with children on motorcycle.

“A mother who could appreciate her son’s initiative and autonomy was a huge asset to his future,” according to one of the study’s conclusions that I found most fascinating. Mothers of high-scoring males praised their sons’ aggressiveness, telling researchers that their sons were “fearless to the point of recklessness,” “could fight any youngster on the neighborhood,” and “is a tyrant in a manner that I like.” In other words, moms who encouraged their sons to embrace their boyishness increased their chances of becoming successful, mature men.

The Importance of a Father’s Influence

Vintage father and sons fishing in pond.

The Grant Study also discovered impacts that were only attributed to fathers. Fathers who loved their sons instilled in them the following values:

  • increased ability to play
  • vacations are more enjoyable
  • a higher chance of being able to utilize comedy as a healthy coping method
  • greater acclimatation to and satisfaction with life after retirement
  • In early adulthood, there is less worry and less bodily and mental symptoms.

In the negative column, “it was not the guys with bad mothering who were much more likely to have terrible marriages across their lives, but the ones with poor fathering.” Men who did not have a healthy connection with their dads were “far more likely to term themselves pessimists and to report having difficulty letting people get close,” according to the study.


If there was any question, dads are very important: When everything was said and done, a man’s connection with his father — “a variable not even suggestively connected with the maternal relationship” — very strongly predicted his total life satisfaction at age 75.

The Maternal Grandfather’s Mysterious Influence

When Grant Study researchers looked into whether a man’s direct family’ longevity influenced his odds of succeeding, they discovered that the age at which his mother, father, maternal grandmother, and both paternal grandparents died had no effect on his Decathlon score. However, there was a “significant and surprising relationship between maternal grandfathers’ [MGFs] age at death and the mental health of their grandsons”:

  • Guys with the highest Decathlon of Flourishing scores had MGFs who lived nine years longer than men with the lowest scores.
  • Guys who never visited a psychiatrist had MGFs who lived nine years longer than men who saw psychiatrists often.
  • Guys with the most mentally well MGFs lived 15 years longer than men with the most depressed MGFs.
  • MGFs of guys with the least anxiety lived 27 years longer than MGFs of those with the highest worry(!)

Vaillant draws the conclusion that “long-lived maternal grandfathers indicate extraordinary psychological stability in their grandchildren” based on these fascinating data points. It’s unclear why this is the case; it’s possible that a man’s mental health is partially inherited and stems from the MGF.


Marriage and Men

Vintage couple on wedding photograph.

A man’s early interactions were not the only ones that influenced the course of his life. His friendships throughout his forties and fifties, as well as the quality of his marriage, all played a part.

Vaillant discovered the following when he assessed the men some decades ago using “Adult Adjustment Outcome determinations” (a type of older version of the Decathlon of Flourishing, from what I gather):

“All fifty-five Best Outcomes had married young and remained married for the majority of their adult life.” (We subsequently heard that just one of those men’s marriages had ended in divorce by the time they were eighty-five.) Five of the seventy-eight Worst Outcomes had never married, and thirty-five (45 percent) of the marriages had ended in divorce by the age of seventy-five. Three times as many of the Best Adjusted men had happy marriages for the rest of their lives as the Worst.”

For the inner-city males in the Glueck Study, the impact of marriage was even more pronounced: “two-thirds of the never-married were in the lowest five in overall social ties, 57 percent were in the worst fifth in income, and 71 percent were rated as mentally ill by the Study raters.”

These findings were not unexpected, given marriage has already been linked to improved life outcomes for males in other research. Vaillant did, however, uncover a few unexpected discoveries:

  • Earlier in his career, Vaillant believed that divorced men would have a difficult time remarrying – that their first marriages had failed due to psychological qualities and behaviors that would doom future efforts at nuptials. When he checked in with the men at the age of 85, he discovered that 23 of the 27 divorced and remarried men were in happy marriages that had lasted an average of 30 years. A man’s inability to thrive in a second marriage did not indicate he couldn’t succeed in his first.
  • Alcoholism – either the men’s or their wives’ – was the single most critical factor in all of the research participants’ divorces. It was shown to be the cause of 57 percent of divorces. While women were normally upfront about their husbands’ drinking issues, husbands were frequently hesitant to speak about their spouses’ drinking problems, therefore it took over 70 years for this discovery to be made.
  • While co-dependence is frequently associated with unhappy and unhealthy relationships in our society, it has been linked to happy and healthy marriages.
  • This reliance, like marriage bliss, grows with time. Only 18 percent of males between the ages of 20 and 70 said their marriage has been continuously joyful (as opposed to so-so or dissatisfied) for at least 20 years. (The low number might be due to generational differences; the WWII generation had different criteria for picking a mate and marital expectations.) However, 76 percent of those over the age of 85 stated their marriages were happy. As people become older, they become more reliant on one another, and we tend to recall only the positive things and forget the negative. As they approach the end of their lives, husbands and wives become more valuable to each other.

Overall, the Grant Study found that having a happy marriage is a huge plus in a man’s life. So, what constitutes a happy marriage? Vaillant doesn’t go into great detail about it, but he does provide an example of what is likely the most successful marriage in the research. This pair, whom Vaillant refers to as “the Chipps” (a pseudonym), loved a variety of hobbies, including sailing, an annual canoeing trip to Nova Scotia, and daily walks of three miles. They always maintained a sense of humour in the face of adversity. Instead of turning to passive hostility, the couple discussed their problems openly, and “even confrontation was filled with humor.” “He (and his wife) had been giving their marriage great ratings for six decades” by the time he was 80, and “I’ve lived happily ever after,” he gushed to his interviewer. Indeed, when Vaillant went through his notes on Mr. Chipps, he discovered that he had written that he was “probably the happiest guy in the study.”


Those Who Have Had an Unfavorable Start in Life Have Reason to Hope

Vintage kids eating at dinner table.

Vaillant finds that “the bulk of the men who thrived discovered love before thirty, and that was why they flourished” after studying the relationship between childhood, marriage, and a man’s life trajectory. Men who had warm interactions as children, whether familial, romantic, or platonic, went on to have the fullest, happiest, and most successful lives.

Why is this the case? Men who were loved as children and learnt to love as adults have excellent mental health, resilience, and closeness — attributes that “represent the process of replacing narcissism with empathy” and lead to more confidence, autonomy, social and emotional intelligence, and maturity. These characteristics lead to greater connections as well as success in other areas (such as one’s work). Men who had a difficult upbringing, on the other hand, have a harder time building close connections, are more likely to be “pessimistic and self-doubting,” and are “handicapped later in learning the assertiveness, initiative, and autonomy that are the foundations of successful adulthood.”

For those readers who grew up with a lot of warm, loving support, the results above are likely an eye-opening look at some of the reasons they’ve been able to discover a good route in life. It is hoped that it would motivate individuals who are presently or wish to be dads to build a loving and caring environment for their own children.

However, these results may seem sad and fatalistic to readers whose upbringing was less than ideal. However, not all hope is gone. The Grant Study shows that having a bad upbringing does really stack the deck against you – there’s no getting around it. “People really can change, and people really can develop,” according to the research. Childhood does not have to be a source of gloom or destiny.” Some of the individuals who had a rocky start in life were able to turn their fortunes around and succeed in subsequent years. How did they pull it off? “Restorative marriages and growing [psychological] defenses,” according to Vaillant, are “the soil from which fresh resilience and post-traumatic development arise.”

As a Healer, Marriage

Vintage couple on wedding day holding "please do not disturb" card.

As we’ve seen, a man’s score in most of the events in the Decathlon of Flourishing was substantially influenced by his loving childhood. However, not all of them. “Dismal childhoods were not necessarily related with bleak marriages,” Vaillant discovered.

“With the exception of a man’s connection with his father, a man’s early environment did not predict stable marriage, and even in the absence of a warm parental bond, excellent marriages might be formed—eventually.” Indeed, marriage seemed to be a way of making up for a difficult childhood. “The most significant turning moments… for most of these disturbed people were finding a loving friend and marrying an accepted spouse,” psychologist Emmy Werner said after almost fifty years of tracking disadvantaged kids.

Vaillant discovered that the guys in the research who hadn’t learnt to love and be loved as a youngster but went on to succeed against the odds saw marriage as a second opportunity to learn about intimacy. (Having children allowed them to expand their hearts in new ways as well.) While Vaillant discovered that “the most reliant adults emerged from the most miserable childhoods,” as previously said, mutual dependency may be beneficial. It did, in fact, prove to be very therapeutic for these gentlemen. Finally, marriage “offers a chance to soothe some of the loneliness of dismal early years, however unsatisfactory.”


Even more intriguing, while many people believe that two people with “baggage” will have a difficult time forming a successful marriage together, Vaillant discovered that this is not always the case: “It turned out that happy marriages after eighty were not associated with either warm childhoods or mature defenses in early adulthood—that is, you don’t have to start out ‘all grown up’ to end up solidly married.” Marriage, on the other hand, may be the ideal “school” for learning how to be a mature guy.

Defenses that have matured

Aside from warm connections, developed defenses and character qualities were two of the most important elements in predicting a man’s Decathlon score.

Our “involuntary psychological coping style” – the ways we instinctively respond to and deal with setbacks, frustration, pain, and so on – is known as mature defenses. Passive hostility, projection, and denial are examples of immature defenses. They are attempting to shift blame for what occurs to others. Men with mature defenses, on the other hand, take responsibility for their actions and try to find a healthy way to deal with life’s challenges. Keeping a sense of humor, finding a pleasant alternative when you can’t obtain what you want, being selfless, and handling issues with tenacity and stoicism are all examples of effective coping skills. The twelve men with the most mature coping methods earned more than $200k per year than the sixteen guys with the most immature coping approaches.

These mature defenses, according to Vaillant, cannot be built only via willpower; your upbringing, environment, and even genetics all play a part. However, you have some influence over them and may actively build and grow them throughout your life.


There are a few character qualities that are significantly linked to thriving, and we can cultivate them to a larger extent than we think.

When Vaillant examined 26 personality qualities that the men in the Grant Study were assessed on in college, he discovered that the attribute “Practical, Organized” best predicted their mental health in middle life. Obviously, this attribute entails the capacity to plan one’s life as well as the ability to defer satisfaction. “Prudence, thoughtfulness, willpower, and tenacity in junior high school were the strongest predictors of occupational success at age fifty,” according to a linked research.

Vaillant discovered another similar feature, “Well Integrated,” which was linked to a whopping eight Decathlon events. Men who were “fully integrated” were described as “stable, dependable, thorough, truthful, and trustworthy,” but those who were “incompletely integrated” were described as “erratic, unreliable, sporadic, undependable, badly directed, and little organized.” The Well-Integrated males outperform the Incompletely Integrated men in the following ways:

  • Were they 4X more likely to have a happy marriage?
  • On average, they lived seven years longer.
  • In old age, they were far more likely to be physically active and mentally intact.

Being Involved

vintage young man riding bicycle with a smiling face in down street.

Finally, although physical type was not shown to be a major predictor of a man’s score on the Decathlon of Flourishing, athletic prowess was. That is, it seems that, although a man’s body type had no bearing on his life trajectory, what he did with that body did (remember, Churchill was born an endomorph who battled it every step of the way!). The benefits of physical training, as we know, can strengthen our discipline, boost our minds, and impart metaphorical life lessons about the importance of things like humility and consistency; staying in shape, as we know, can strengthen our discipline, boost our minds, and impart metaphorical life lessons about the importance of things like humility and consistency. It’s possible that this is why the participants’ performance in a physical endurance test was shown to be a greater predictor of their capacity to create successful relationships than their subsequent health. We become better persons as a result of exercise.


You Can Become the Man You Want to Be, Regardless of Your Upbringing

It’s hardly surprise that skills like organization, discipline, and reliability predict success in middle and late life; they’re “exactly the attributes individuals need to find ways around setbacks, and make the most of victories when they come along,” according to Vaillant. Fortunately, no matter how much or how little instruction we had in our childhood, we may acquire these abilities in ourselves. Those who were never taught as a boy the necessity of time management, perseverance in the face of failures, and building trustworthiness will have a more difficult road ahead, but these qualities may be learned at any age.

While it is easier to form new habits until the mid-twenties, when your brain is at its most malleable, our brains stay flexible and moldable throughout our lives. In reality, until the age of 60, the process of myelinization, which improves the functioning of our neurons, continues. Our prefrontal lobes (which serve as the practical, ordered CEO of our brains) may improve their ability to monitor the limbic areas of our brains at this period (which cause us to be unthinkingly impulsive). As a result, Vaillant discovered that research participants, regardless of their background, might evolve through time — becoming smarter, more patient, more mature. The more you actively seek and practice such attributes, the more you may help and speed that process. So, if you can, begin working on your character as early as possible, and continue to practice the attributes of mature masculinity throughout your life. “What the guys did with a lovely or dreary upbringing had as much to do with future achievement as the childhood itself,” Vaillant observes.

Conclusion: All You Need Is Love (Even If You’re a Dude)

Vintage family photo.

“The Grant Study’s recent years have proven that our lives as we get older are the sum of all our loves.” –Vaillant, George

For millennia, people have argued and pondered what makes life worthwhile. Is it because of your parents’ social standing? Is it a lucrative profession? Is it the body type you were born with?

Valliant’s explanation, based on decades of research into the lives of men aged 18 to 90, is this: “Happiness is love.” “End of story.” It’s a conclusion we’ve all known for a long time, but it’s good to be reminded of it, and to see that it’s supported not just by intuition, but by over 80 years of study.

Character characteristics are important as well, but their true value lies in assisting us in replacing sporadic narcissism with the constant maturity that leads to meaningful partnerships. Perhaps it seems corny, but we are all here to love and be loved in the end. Love gives us the capacity to “faith in life” and the confidence to achieve our objectives. All of the other wonderful things – job success, prominence, adventure – will inevitably come if we fill our lives with warm, deep connections.


Character characteristics are important as well, but their true value lies in assisting us in replacing sporadic narcissism with the constant maturity that leads to meaningful partnerships. Perhaps it seems corny, but we are all here to love and be loved in the end. Love gives us the capacity to “faith in life” and the confidence to achieve our objectives. All of the other wonderful things – job success, prominence, adventure – will inevitably come if we fill our lives with warm, deep connections.


George Vaillant’s The Triumphs of Experience: The Harvard Grant Study Men



“Love is All You Need: Insights from the Grant Study” is a book about the “mature adaptations” of humans. It discusses how love has been found to be one of the most important factors in human survival.

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