‘I would watch every episode’: charting the 30-year study into Australian women’s ageing

For far too long, says Prof Cassandra Szoeke, discussions about women’s health have focused on what she calls “bikini health”, that is, relating only to areas of the body covered by a two-piece. But when the principal investigator of the longest ongoing study of women’s health in Australia gives presentations on this topic, she talks about brains and hearts.

After all, women comprise two-thirds of people living with dementia and it is their leading cause of death, followed by heart disease and stroke.

“These are not things we think of as women’s health,” says Szoeke, “and maybe that’s why women are dying of them.”

In 1990, a team from the University of Melbourne embarked on an ambitious, landmark study that has by now followed hundreds of middle-aged Australian women into older age over three decades – and is still going – to shine a light on this long-neglected area of research. Szoeke joined the team 20 years ago.

“If this were a TV show, I would watch every episode,” Szoeke writes in her new book, Secrets of Women’s Healthy Ageing. “These women have shared so many aspects of their lives with researchers: health, social and emotional, and in many cases their deepest, darkest secrets.”

The book describes revelations gleaned from the study mingled with the body of research to date, highlighting the importance of exercise, diet, mental stimulation, sleep, social connectedness and attitude – no matter what the circumstances.

Information from hundreds of women involved in the study has formed a compelling narrative about women’s ageing. Szoeke continues with the TV show metaphor: “Picture more than 400 amazing female characters, appearing in more than 30 seasons and still going strong.”

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“The women at the heart of this story come from all walks of life ... many were married, some happily, some not,” writes Szoeke. “Some were dealing with the tumult of divorce. Some were single, some shared their lives with other women. Some, not all, were in paid work. Those caring for children or ailing parents could have told you their work was never-ending. Some lived in suburban homes with sports timetables stuck to the fridge; in apartments with freezers stocked with Lean Cuisine; or on new estates at the city’s fringes, where the mortgages were as big as the houses.”

If there’s just one lesson gleaned from the study’s observations, Szoeke tells Guardian Australia, it’s to make health a priority in our day-to-day lives. “Probably the most important thing is to think about our health, because it is something that just doesn’t get on our to-do lists.”

While women generally aren’t smoking as much as they used to and are getting their regular pap smears and mammograms, Szoeke’s concern is that they’re not following simple everyday guidelines for good health. A related health survey the team conducted with more than 20,000 women revealed that fewer than half of them had a healthy weight, fewer than a third were getting enough activity, fewer than a fifth were eating enough fruit and veg, and fewer than one in 10 were eating enough fish and legumes.

Given that, according to the World Health Organization, such lifestyle factors can prevent 80% of diseases, this is a glaring gap that prompted Szoeke to communicate the research findings in her book. Most surprising to her was the discovery that lifestyle habits are just as vital at 80 as they are at 40.

“Across 30 years we were expecting that what we do in middle life is the most important and that over time it would get less important,” she says. “But across all 30 years of the study to date, every single day counted. It was cumulative. Which meant you could make up for lost time.”

Being physically active, for instance, mattered regardless of what form it took. Contrary to expectations, people who did high-intensity workouts weren’t better off. What turned out by far to be most important is moving every day – even if it’s just housework or walking around the block. Indeed, a Harvard study found that 15 minutes of physical activity a day can prolong your life by three years. Most important is to do something you enjoy.

The benefits extend beyond physical health – for every day of being active, Szoeke’s participants were able to remember an extra word in a memory recall test. This corresponds with other research that shows outstanding benefits of physical activity for preventing dementia.

“So any physical activity is the really number one thing you can do for health,” she says. “And the more you do it, the better you’re at it.”

On reflection, Szoeke says the cumulative impact of daily habits makes sense. Chronic diseases of ageing, which include diabetes, hypertension, heart disease, dementia, osteoarthritis and osteoporosis, don’t happen overnight – they take decades to develop. Dementia, for instance, could start developing 30 years before symptoms start appearing.

The same goes for the food we eat – it’s daily habits that count. Going on a diet for a month or even two years or so is not going to allay chronic diseases in the long term. “So it really is about having the best possible food for your body each and every day,” says Szoeke. “You’re a wonderful machine and you want to be using you for a hundred years or so, so use premium fuel and avoid toxins.”

Simply put, the study confirmed that the foods most common to healthy ageing are vegetables and fruit. Close behind are legumes and fish. The worst were processed foods and sugar. “If you want to focus on a diet, I’ve just got one bit of advice: don’t have a western diet,” says Szoeke.

Healthy lifestyle factors become especially important following menopause. According to the Australian Bureau of Statistics, women over 65 are more likely than their male counterparts to experience “severe or profound disability limiting activities of daily living”. It’s now understood that hormones play vital roles in every aspect of health, yet there is much still to learn about them and their unique impact on women.

Another contributor to physical and mental health that cannot be underestimated is social connections.

“It doesn’t mean you have to be an extrovert, far from it,” says Szoeke. “Some people want to be alone, but that’s very different to being lonely.” It’s well established that people who are lonely or isolated have poorer immunity and are more likely to suffer health problems such as heart attack, stroke or depression.

A sense of purpose can play a role. One participant who considered herself a recluse was invited to join a club because she was a good bookkeeper. She didn’t get involved in many of the social events, but she came to realise that she was making an important contribution. “People were telling her it was of great value,” says Szoeke, “and she found that suddenly it became a big part of her life and she really valued it.”

Others found purpose and connection through joining a community organisation, the local choir, or – one who described herself as a hermit after her husband died – just being part of a monthly film club in her apartment complex.

Amid all of this, attitude emerged as another key factor to healthy ageing. “It is the surprising secrets that are the most precious,” Szoeke writes, “and one of the ones that surprised us most was that not all socially active women are fit and well.” Many women who engaged with grandchildren or volunteering reported aches and pains, but they took it in their stride and focused on their positive contributions.

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Indeed, those with a positive attitude maintained a positive mood years later regardless of their health status. And at a time of life that can bring massive changes with losing a partner, children leaving home or ill health, an ability to adapt was also important.

“If you act on the secrets our women have shared with you – to move, to eat well, to stress but not distress, to connect – you will build your intrinsic capacity,” writes Szoeke. “Intrinsic capacity is your ability to weather the storms life throws at us. It is what provides you with resilience in the face of inevitable changes.”

Importantly, Szoeke dedicates an entire epilogue to the need for science and medicine to recognise and address the vast differences between male and female health. For the new and ongoing insights from the study, she expresses enormous gratitude to the participants.

“We would know nothing without them,” she says. “These women are really quite unique in their altruism and their desire to help. And one thing I found is they actually changed our research through their suggestions. It’s been the women themselves giving us the questions they want answered.

“Through my 20 years [in the project], what has been the most important for me, and helped my health, is when these women give tips. The sharing of stories is so powerful and meaningful, and honestly it’s the best way to adopt advice.”

Secrets of Women’s Healthy Ageing by Prof Cassandra Szoeke is published by Melbourne University Press and is out now