Happiness with one’s life seems to be the elusive “secret” of those who age to 100 and beyond. 

However, researchers who have studied the lives of centenarians are still not sure how to define happiness. 

University of NSW scientist, Adrian Cheng, says the happiness of centenarians is important because examination of subjective wellbeing in “this unique group can reveal factors associated with good psychological health”. 

According to Mr Cheng, studies have revealed that while centenarians consistently have similar levels of happiness as younger age groups, it was unclear if this was the same for their life satisfaction, positive emotions, enthusiasm, and joy. 

So, researchers retreat to the empirical and observable certainty that maintaining physical and mental health, and a good dose of genetic luck, are crucial. 

He found that centenarians who think they are healthy are likely to lead a satisfied life. 

“Having a positive view about our own health, or possibly simply having better health, as we age is important as part of the ageing process,” he said. 

However, fatigue and vision impairment were linked to an unhappy older life. 

Sokola Radonic is a homemaker in Zagreb, Croatia. She is aged 101 at the time of writing and she confirms Mr Cheng’s findings. 

“What contributed to my longevity? Nature, food, singing in a choir until my 80s, and dancing,” she told The Guardian in a report on centenarians. 

“You need to have lots of patience and to endure some things. You shouldn’t quit right away. For happiness, health is the most important – and love for other people. Wealth is in last place.”  

You can read about the secrets of other centenarians here.  

A Boston University study of centenarians, the largest of its kind in the world, found they age slowly, delaying age-related diseases to much later in life. 

Genetics plays a huge role in our longevity. While getting to age 90 is roughly 30% genetics and 70% health behaviours, by age 110 it is likely the opposite: 70% genetic. 

The study says we can do four things to increase our chances of living longer: 

1. Manage stress. 
2. Eat right, keeping meat consumption to a minimum. 
3. Don’t smoke. 
4. Exercise regularly. 

Happiness is not on the shortlist. However, it could be that we can enhance the likelihood of happiness by achieving these other tips, and even a few more.

Researchers, writing in The Conversation found centenarians got up to 65% of their energy intake from carbohydrates, 12% to 32% from protein, and 27% to 31% from fat. 

Foods they eat include rice and wheat, fruits, vegetables, and protein-rich poultry, fish, and legumes. 

This dietary pattern, similar to the Mediterranean diet, is linked to lower risks of physical function impairment and death. 

Cutting down on salt might also help. 

Centenarians experience less hypertension (high blood pressure), and dementia or cognitive impairment. 

People reviewed in a University of NSW School of Population Health study took an average of 4.6 medications. The most frequently used medications included blood pressure medications and drugs for heart disease. Non-centenarians in this study took 6.7 medications on average. 

The researchers emphasise that while the type or number of prescribed medications may not be within a patient’s control, it’s important for doctors to prescribe medications only when necessary, fully inform patients about benefits and risks, and regularly review treatment plans. 

Getting good quality sleep supports the immune system, stress hormones, and cardiometabolic functions such as obesity, high blood pressure, and diabetes. Good sleep increases the years of good health and fewer and less severe chronic diseases. 

If you can, sleep for six to seven hours a day and keep a regular sleep routine by creating a restful environment, exercise regularly and manage stress.