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Midlife Milestones Past and Present

Today, as I celebrate my 40th birthday, I find myself at a unique crossroads between my personal journey and my professional trajectory as a gerontologist and epidemiologist. This milestone offers a moment of reflection, not just on the personal level but also on the profound shifts in the aging process that humanity has experienced over millennia, centuries, and recent decades. The way we perceive age and aging, especially the landmark of turning 40, has dramatically transformed from what it was 4000 years ago, 400 years ago, or even 40 years ago. This transformation is not just a testament to medical advancements but also to changes in societal structures, roles, and expectations.

Putting things into perspective, let's consider life expectancy in the context of aging dynamics. Around four thousand years ago, during the time of the ancient Sumerians and Egyptians, average life expectancy at birth was likely between 30 to 40 years; a figure skewed by high infant mortality rates. Those who survived childhood could live into their 50s or 60s, but reaching the age of 40 would be considered a significant achievement. What we would consider ‘older age’ by contemporary standards would be an age attained by a privileged few. Fast forward to 400 years ago, in the 17th century, the global average life expectancy was still under 40 years. It wasn't until the 19th and early 20th centuries that we began to see dramatic increases in life expectancy, thanks to improvements in public health, sanitation, and the advent of antibiotics. By the late 20th century, the global average life expectancy had risen to over 70 years, albeit with significant variations between countries. Today, turning 40 is often viewed not as a sign of impending senility, but as a midpoint of life, a time for reflection, growth, and anticipation of what the next decades will bring. This shift is not only due to increased life expectancy, which now stands at approximately 73.33 years globally (or 83.11 years for my fellow Canadians), but also to changes in how we live our lives. As one might imagine, the roles and expectations of individuals in their 40s have changed significantly.

Historically someone in their 40s might have been preparing for the twilight of their life, with major societal and familial contributions behind them. Now, many of us are in the prime of our careers, continuing to ascend professionally, or even embarking on new ventures and challenges. The notion of a ‘midlife crisis’ has given way to a ‘midlife opportunity’, where the experiences and wisdom gained over four decades can be leveraged in both personal and professional contexts.

The roles within families and societies for those in their 40s have also shifted. Consider my own situation: at 40, I am the father of a toddler. In another era, I could have been a grandfather or even a great-grandfather.[1] This change is reflective of broader demographic trends, where people are choosing to start families later in life for various reasons, including career aspirations, personal development, and/or financial stability.

As I stand at the threshold of my 40s, I am struck by the contrast between the historical perception of this age and my own experience. The advancements in healthcare and changes in societal norms have not only extended our life expectancies but have also enriched the quality of life we can expect as we age. Yet, this is not without its challenges. The increase in life expectancy brings with it the need to ensure those extra years are lived in good health, seeking to increase not only the quantity of years lived, but also the quality of those years. As a gerontologist, I am acutely aware of the importance of adopting a healthy lifestyle, staying mentally active, and maintaining strong social connections to enhance both lifespan and healthspan. These factors are crucial not just for individuals but for society as a whole, as we navigate the complexities of an aging population.

Celebrating my 40th birthday, I am filled with gratitude for the progress we have made in understanding and improving the aging process. I am also mindful of the challenges and opportunities that lie ahead, both personally and professionally. The journey of aging is a shared human experience, one that has transformed significantly over time and continues to do so. My hope is that we can all embrace this journey with knowledge, grace, and a sense of adventure, making the most of the years we have and enriching the lives of those around us.

[1] This would mean that three consecutive generations of mothers would have to conceive at around the age of twelve. Therefore, although this is biologically possible, we can safely assume that situations such as this were rare.

About the Author

Theodore D Cosco joined the Oxford Institute of Population Ageing in 2016 as a Research Fellow. Dr. Cosco is a Chartered Psychologist (British Psychological Society) trained in applied social research methods (MSc 2011, Trinity College Dublin) and epidemiology (PhD 2015, University of Cambridge), and Assistant Professor of Mental Health and Aging in the Department of Gerontology, Simon Fraser University. His research interests include resilience, mental health, and the interface between technology and healthy ageing. 

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