My mother died in 2011, a little more than two months before she turned 65. The sad irony of the timing of her death -- just before what many still consider retirement age -- was not lost on me, a writer of retirement-related content for The Motley Fool. However, my mother was fortunate enough to have retired early and enjoyed several years out of the rat race before she passed away. 

Her early death was also a stark and rather frank reminder that, while most Americans are living longer, more active lives than ever before, it's not the case for everyone. None of us are guaranteed to live into our 80s or beyond. 

Smiling woman at her retirement party.

Image source: Getty Images.

The statistics on aging, and what it means for retirement savers

According to Social Security Administration data, Americans have steadily lived longer and longer lives. The chart below shows how many more years, on average, a 65-year-old American has lived since 1900, as well as the expectations that this trend will continue to the end of the current century. 

Table showing the increased life expectancy of American men and women aged 65 since 1900

Table source: Social Security Administration.

For today's seniors, this means most men who reach 65 will live another 19 years, while the average 65 year-old woman will live almost 22 more years.

The amazing news is that two decades of retirement -- assuming a retirement age of 65 -- is a lot of time to spend with family, travel, and otherwise pursue passions and activities that may not be compatible with full-time work. But it also requires a significant amount of money to pay for that many years without a steady paycheck. For instance, if you need to generate $50,000 per year in income from your retirement savings, you'd need to have a $1.25 million nest egg, based on the 4% retirement rule (which has flaws, but is a starting point).  

The idea of having to save up so much money is daunting. However, there's a big difference between saving $1.25 million and building a $1.25 million portfolio over the long term. For example, if someone started contributing 7% of their salary (with a starting salary of $50,000) in their retirement account at age 25 and invested in a low-cost S&P 500 index fund, they would have a $1.25 million retirement portfolio at age 59, based on the market's historical 10% average rate of return. 

The best part? Their total contributions would be around $175,000. That's the power of compound growth over a very long period of time. 

The point is, invest -- don't just save -- for retirement. Start as early as possible. Contribute as much as possible. 

The lesson of dying early 

My mother was diagnosed with non-Hodgkin's lymphoma at age 47. And while this disease would contribute to her early death 17 years later, she had every expectation of living much longer. After all, her mother lived into her 80s, and her father, even though he suffered from emphysema for decades, lived to 78. 

But as John Lennon wrote, ""Life is what happens to you while you are busy making other plans." Fortunately, she and her husband were able to generate enough income from a small business, which, combined with Social Security and retirement savings, was enough to make ends meet and allow my mother to quit work at age 60. They had to live within a budget, but they weren't in poverty. 

Unfortunately, too many people aren't in that same situation and struggle mightily. And the reason why is because most people simply don't take action to start preparing for retirement when they're young, and time is on their side.

Older couple sitting on a deck.

Image source: Getty Images.

It's what you do today that will determine if you can retire early

By the time most people find out they're not going to live as long as the average American, it's just too late to do anything about how much money they have for retirement. Too often that means either working until you're no longer able, or going without in retirement. 

Here's the bottom line: Nobody complains that they saved too much for retirement. But far too many Americans are faced with the exact opposite problem, and many will struggle in the years before they die because of it. So if you want to be in the position to retire early -- whether it's because you're faced with the unfortunate prospect of dying early or simply because you're ready to retire -- it's the steps you take now that could make all the difference.

My mother was fortunate to be able to step away from the workforce early, even though she died much sooner than expected and years younger than average. If you want to be able to do the same thing, it's up to you to start contributing as much to your retirement portfolio as you can, as soon as you can. 

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