Recently I’ve begun taking an interest in a field called public health. The World Health Organisation has defined public health as:
“The art and science of preventing disease, prolonging life and promoting health through the organized efforts of society” — Acheson, 1988
As time has gone on, there have been some studies that have helped public health to become less of an art and more of a science.
My favourite two public health studies are:
- The Longevity Project (also known as ‘The Terman Study’)
- The Harvard Study of Adult Development (also known as ‘The Grant Study’)
What makes these studies exceptional is their duration (80+ years) and the willingness of their participants to continue to be regularly assessed throughout their entire lives. Called prospective longitudinal studies, they both give us a rare chance to actually see which factors contribute to later illness or long-term health and well-being.
I aim to share these groundbreaking findings with you.
“The saddest aspect of life right now is that science gathers knowledge faster than society gathers wisdom.” — Isaac Asimov
1. The Longevity Project
Over 1,500 of the most promising and brightest boys and girls were initially recruited in 1921 by the Psychologist Lewis Terman. He died in 1956, but the study continued for decades afterwards. All participants were born around the year 1910 and were studied for over 80 years to figure out who would live the longest and why.
Although each of the children was considered to be potentially gifted at the time, not all of them lived long and happy lives. Fortunately, the extensive data of these subjects has been intensely assessed and analysed for over twenty years at The University of California, Riverside.
The significant findings of the study have been summarised in the 2011 book “The Longevity Project: Surprising Discoveries for Health and Long-Life from the Landmark Eight-Decade Study” by Howard Friedman and Leslie Martin. I listened to this audiobook recently, and was quite surprised with some of their key results:
The 10 TRUTHS of Longevity:
- It is important to live honestly
- “A key part of one of the healthy paths is called ‘The High Road.’ Such an individual has good friends, meaningful work and a happy, responsible marriage. The thoughtful planning and perseverance that such people invest in their careers and relationships promote long life naturally and automatically, even when challenges arise.”
- Do NOT send your children to school at an earlier age than their peers
- “Starting formal schooling at a very early age turned out not to be a great idea for most. Children need unstructured play time, and they need to get along with their peers; starting out young seemed to alienate them.”
- Illness is NOT random
- “Those that live longer are often healthier throughout their years and (managed to) avoid serious ailments altogether.”
- “Those who are healthier tend to be happier, and those who are happier tend to be healthier.”
- “It’s never too late to choose a healthier path. The first step is to throw away the lists and stop worrying about worrying.”
- “Thinking of making changes as taking ‘steps’ is a grand strategy, You can’t change major things about yourself overnight. But making small changes, and repeating those steps, can eventually create that path to longer life.”
- Good marriages lead to better health, especially for men
- “Marriage is only health-promoting for men who are well-suited to marriage and have a good marriage. For others, it is more complicated.”
- “Women who stayed single, were widowed or got divorced often thrived more than women who were married to troublesome husbands.”
- “Men who stayed divorced were at really high risk for premature mortality.”
- Divorce during childhood predicts early death in adulthood
- “The single strongest social predictor is parental divorce, as it often pushes the child into many unhealthy directions, including heavier drinking and smoking, less education, lower career achievements and a greater risk of later divorce themselves.”
- Follow the long-term recommendations that are right for you
- “The long-lived did not find the secret to health in broccoli, medical tests, vitamins or jogging. Rather they were individuals with certain constellations of habits and patterns of living. Their personalities, career trajectories and social lives proved highly relevant to their long-term health, often in ways we did not expect.”
- “You need to make changes that will be sustainable in the long term. We say, if you don’t like jogging, don’t jog! Instead, begin doing things that you really enjoy and can keep up, like a walk at lunchtime with a friend or vigorous gardening.”
- “The usual piecemeal suggestions of relax, eat vegetables, lose weight and get married are lifesaving for some, but neither effective or economical for many.”
- “Some of the minutiae of what people think will help us lead long, healthy lives, such as worrying about the ratio of omega-6 to omega-3 fatty acids in the foods we eat, actually are red herrings, distracting us from the major pathways. When we recognise the long-term healthy and unhealthy patterns in ourselves, we can begin to maximise the healthy patterns.”
- Conscientiousness is the most critical personality factor for longevity
- “Conscientiousness is very important. Unconscientious boys, even bright ones, are more likely to grow up to have poor marriages, to smoke more, to drink more, achieve less education, be relatively unsuccessful at work, and die younger.”
- “Conscientious people stay healthier and live longer for three reasons:
- They do more things to protect their health.
- They are biologically predisposed to be healthier, and
- They tend to end up in healthier situations and relationships.”
- Working hard can be useful for you
- “Those who worked the hardest often lived the longest…especially if they were involved in meaningful careers and were dedicated to things and people beyond themselves.”
- “It was clear that working hard to overcome adversity or biting off more than you can chew — and then chewing it — does not generally pose a health risk. Striving to accomplish your goals, setting new aims when milestones are reached, and staying engaged and productive is exactly what those heading to a long life tend to do. The long-lived didn’t shy away from hard work; the exact opposite seemed true.”
- Resilience is protective for health
- “Depending on the circumstances, a traumatic event such as parental divorce could actually contribute to a longer life if the child learned to be resilient.”
- “Resilience is important, and can be achieved via a sense of personal accomplishment, strength of character and maturity.”
- “Combat veterans are less likely to live long lives, but surprisingly the psychological stress of war itself is not necessarily a major health threat. Rather, it is a cascade of unhealthy patterns that sometimes follows. Those who find meaning in a traumatic experience and can reestablish a sense of security about the world are usually the ones who return to a healthy pathway.”
- Human connection is important
- “Having pets can improve well-being, but they do not help people live longer and are not a substitute for friends.”
- “People who feel loved and cared for report a better sense of well-being.”
- “The clearest health benefit of social relationships comes from being involved with and helping others.”
- “It is important to be well-integrated into your community.”
- “Connecting with and helping others is more important than obsessing over a rigorous exercise program.”
- “The groups you associate with often determine the type of person you become — healthy or unhealthy.”
2. The Harvard Study of Adult Development
The study began in 1938, and the goal of this longitudinal prospective study was 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 the years of 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:
- “Alcoholism is a disorder of great destructive power.”
- Alcoholism precedes marital difficulties and is the leading cause of divorce, with 57% of the divorces being 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.
- “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 with men who have an IQ higher than 150.
- “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 more likely to cease having sex by the age of 68.
- “For good or ill, the effects of childhood last a long time.”
- A warm childhood relationship with the mother predicts greater financial earning later in life ($87,000 more in comparison to 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.
- “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.”
- This essentially means that what goes right during childhood tends to matter much more than what goes wrong.
- If bad things happen, as long as they are outweighed by the good, you are more than likely to turn out okay still.
- “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 predictively by the time the men were fifty; by the time they were 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 of the 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 with 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.” or in other words — “Happiness is love. Full stop.”
- Spouses mutual dependence on each other was associated with happy and healthy marriages. At age eighty-five, 76% of the men still alive said that their marriages were happy.
- “The majority of the men who flourished found love before thirty, and that was why they flourished.”
For more information, see the latest director of the study Robert Waldinger talk about the key findings from the Harvard Study of Adult Development. His TED talk has over 16 million views at this time of publication:
I hope that you find these highly significant findings as fascinating as I do. They really do highlight the benefits of investing in ambitious public health studies such as these two.
They also give us the best scientifically supported indicators yet of the paths you want to go down or the changes you need to make if you’re going to live a happy, healthy, and long life.
Dr Damon Ashworth