10 Psychological Predictors of Happiness Across the Lifespan

predictors of happiness positive aging

Why do people age differently? Why do some people grow better and happier with age, constantly improving like a fine Cabernet Sauvignon, while other people simply decay with age? Can we find predictors of happiness?

The only way to discover the secrets of a long and happy life would be to recruit a large group of young people into a study, then continually follow and assess them over the course of their lives.

This would be a monumental task.


The Harvard Grant Study

Eighty years ago a team of physicians at Harvard University began exactly that. They recruited two hundred and sixty undergraduates into a longitudinal study and followed them for life.

The subjects received ongoing physical and mental health examinations, as well as assessments of personality type, career success, marital status, alcohol use, life satisfaction and more. Over the decades the study was expanded to include men and women from more diverse backgrounds.

Initially, the study identified risk factors we now take for granted, such as the harm caused by smoking, obesity, alcoholism, and loneliness. Moreover, the study went on to discover the psychological predictors of health and happiness across the lifespan.

So what psychological factors predict a long and happy life?

Defence Mechanisms

Firstly, it’s important to understand something about defence mechanisms.

Since the days of Sigmund Freud psychotherapists have studied defence mechanisms to better understand how different people cope with stress. Defence mechanisms are the shock absorbers of the soul. They protect us against the harshness of reality by allowing us to distance ourselves from unpleasant thoughts and feelings. For example, most people are familiar with ‘denial’ as a common defence mechanism, but there are more than twenty others.

A key finding of the study was that not all defence mechanisms are equal. Those whose lives turned out badly, as measured by early death, or poor mental and physical health, or low life satisfaction, tended to rely on the same unhealthy defence mechanisms throughout their lives. In contrast, the happiest and most successful people used certain ‘mature’ defences throughout their lives.

Immature Defences

The researchers used the terms immature Vs. mature defences to distinguish between the different coping styles. Examples of immature defences are shown below. These are strategies to avoid. They predict lousy lives. It’s also important to understand people use these mechanisms unconsciously. Those who employ these strategies will deny they are doing anything of the sort.


Denial is a familiar example of how some people buffer themselves against stress. If reality is unpleasant, then reality is wrong! “I don’t have a drinking problem because I hardly ever crash my car. My daughter would never spend the money I give her on drugs. The person I’ve been seeing for five years is trapped in an unhappy marriage and will leave soon. The dark mole on my shoulder hasn’t spread much, and besides doctors don’t know everything.”

The problem with denial is reality usually catches up. We pay a long-term price for short-term comfort.

Passive Aggression

The passive-aggressive person deals with stress by sabotaging the demands placed on them. As if hitting back at the world they punish others by being constantly late, or ‘accidentally’ breaking something when asked to help or claiming they didn’t mean to say anything hurtful. They may use loaded language such as “I know you’re too busy to help me,” or “you’ve done so well given your background.”


Projection is when we condemn in others what we fear in ourselves. Like a movie projector, we project our faults onto other people. It’s always someone else who is dishonest, or lazy or selfish. This is why when two people clash they have more in common than they can admit; – perhaps better not to point this out!

Reaction formation

With reaction formation, a person reduces stress by adopting the opposite feeling or impulse to what they truly feel. More than simple denial where we insist it isn’t so, with reaction formation we go further and insist the opposite is true.

For example, a romantic attraction towards someone unobtainable is transformed into hostility. Or resentment towards an overbearing boss or a difficult relative is transformed as respect. This is why self-righteous people end up in sex scandals. As Hamlet once said, “methinks thou protest too much.”
So what are Mature Defences?

Mature Defences

In contrast to the immature defences above, the happiest and healthiest people in the study used ‘mature’ defences throughout their lives. Here are five examples. Using these strategies in the face of life’s challenges will very likely promote your own happiness and extend your life!


With sublimation, we deal with tension and stress by re-channelling the energy into something more constructive or socially acceptable. You might throw yourself into sports or vent your feelings through a hobby. Interestingly, in 1900s Vienna, Freud believed public interest in erotic artwork was an example of rechannelling sexual impulses that were otherwise socially unacceptable at the time. Freud must have been a fun guy.


Unlike repression where you convince yourself you are not angry with your boss, or your partner or the police officer writing you a ticket, with suppression you know absolutely that you are angry. However, you are insightful and stoic enough to bite your lip and to count to ten. Whereas repression is unhealthy (Woody Allen once said “I don’t get angry, I get a tumour”) suppression involves insight and maturity (yes I am angry, but I’m also in control).


Instead of avoiding stressful issues or deadlines by living in a dream world, it’s better to focus on challenges and plan accordingly. By acknowledging challenges and preparing for them we don’t become overwhelmed. However, burying your head in the sand, or self-medicating with drugs or alcohol gets nothing done and only creates more stress tomorrow. Anticipate, don’t avoid.

Altruism and Kindness

This is one mature coping mechanism that has been absolutely confirmed by positive psychology research. There is genuine satisfaction and pleasure in helping other people. Acts of kindness boost serotonin and lowers cortisol making us stronger in the face of our own challenges. Even in cases of great loss or grief, supporting others experiencing a similar loss is a healthy way of coping.


Humour has been called the Rolls Royce of coping mechanisms. Humour is the alibility to find one small positive in an otherwise bleak situation. If we can’t change the situation, we can still sooth our suffering. Even in extreme situations such as in concentration camps people have described keeping their spirits alive by inventing amusing nicknames for the guards or joking about the food.

People blessed with a sense of humour are difficult to provoke. When Groucho Marx was refused membership to a restricted country club, he didn’t get upset. He wrote back asking if his children, being only half Jewish, could join the club on the condition they would only go in the swimming pool up to their waists.*(Check notes)

All You Need is Love

Finally, the Grant study found the Beatles were right all along. In positive psychology we say ‘other people matter.’ The data from the Grant study shows this is overwhelmingly true. More than money, fame, career success, social class, intelligence or genes the single most important factor in a long and happy life is love. Intimate bonds protect us from life’s hardships, delay mental and physical decline and predict long-term happiness.

Putting it all together

Think about how much fun you are to be around when you are under stress. Not much. Worse still, if you are stuck in immature defences such as denial or projection you are, quite frankly, obnoxious. You will drive love away.

But if you cope by using mature defences such as sublimation, kindness or humour, you may actually bring love closer.

This matters. As Buddha said, ‘life is suffering’ (another fun guy). But if you have one or more people to support you during times of suffering, you’ll more likely bounce back. But if you are alone in the world, if you don’t have someone to support you through painful experiences, you’ll internalize problems, isolate yourself, and live a lifetime of pain.

So, the next time you are checking your phone instead of being present with your significant other, or you’re on social media instead of being with your friends, consider making a different choice.

Take care of love and it will take care of you.



George VaillantFor many years the principal researcher of the Harvard Grant Study was Professor George Vaillant.

When he retired from the study he said:

“The seventy-five years and twenty million dollars expended on the Grant Study points to a straightforward five-word conclusion… ‘Happiness is love. Full stop.’


      • The Grant study is officially known as the ‘Harvard Study of Adult Development. It takes its more popular name from its philanthropist W.T. Grant.
      • The study’s most famous recruit was John F. Kennedy.
      • *Jewish humour often takes the prize for defying those in power. But there are other traditions that support the underdog. Here’s an example of Aussie humour. In the splendid game of cricket, umpires stop play when the light fades. Before the days of digital technology umpires relied on their best judgment to do this. Very occasionally Australian teams would criticise English umpires, perhaps more accustomed to gloomy conditions, for being too slow to halt play. One day an Aussie batsman was struggling in the fading light. As the clouds grew darker he became increasingly frustrated with the English umpires for insisting the game should continue. Eventually he was bowled out. But he didn’t get upset. He reached into his pocket and produced a cigarette lighter. He balanced the lighter on the end of his outstretched bat and used the flame to find his way back to the changing rooms. True story. Sometimes the last laugh is the ultimate consolation prize.

      • Kramer, U. (2010). Coping and defence mechanisms: What’s the difference? Second act. Psychology and Psychotherapy: Theory, Research and Practice, 83(2), 207-221.
      • Johnson, N. J., Backlund, E., Sorlie, P. D., & Loveless, C. A. (2000). Marital status and mortality: The National Longitudinal Mortality Study. Annals of Epidemiology, 10, 224-238.
      • Malone, J. C., Cohen, S., Liu, S. R., Vaillant, G. E., & Waldinger, R. J. (2013). Adaptive midlife defense mechanisms and late-life health. Personality and Individual Differences, 55(2), 85-89.
      • Vaillant, GE (2002), Aging Well, Boston, MA. Little Brown

About the Author

Brad Desmond is an award-winning psychologist with additional post-graduate qualifications in education and training. He is a frequent presenter at national and international conferences and a twenty-year member of the Australian Psychological Society.


  1. Dolline Busolo

    I love this Brad. Very useful for me as am just about to start my masters thesis to character strengths among older people in Kenya. Can we chat by mail.

  2. Gary Makus MPH

    On growing old. There is a growing dichotomy. I usually say that people are like grape juice. You either turn into vintage wine or vinegar. As we get older there seems to be a natural separation of the goats and the sheep before death (which may continue after death).

  3. gillian

    This was lovely. Thank you.

  4. Eyo Asuquo

    Thanks so much. This was quite insightful!

  5. Vinay

    I’d love to learn more about positive Psychology. The title is exciting enough to dive deeper.

  6. Brad

    Hi Martin.
    I tell my teenagers they only need to do one thing in life; to do well enough to put me in a good nursing home. They respond by telling me they’ve already picked it out. Little bas@#rds!

  7. Martin Wilkinson

    Thanks Brad.
    As we get older it is always important to be able to rely on those around you, your family and friends and even very cheeky colleagues who think you are old before your time!!!


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