I'm sorry to have to be the one to break the bad news to you, but someone has to. Why don't you sit down first, though, OK? Now, here are a few things you may not know or may not have wanted to accept:

First, there's that nest egg you've worked so hard to build for your future -- it might not treat you as generously as you think. If you're about to retire and you've got a whopping $500,000 socked away, for example, think about this: Most experts, such as Robert Brokamp who edits our Motley Fool Rule Your Retirement newsletter, recommend withdrawing 4% to 6% from your nest egg annually. Just 5% of a half-million-dollar nest egg will give you a whopping ... $25,000 per year to live off.

And the Social Security payments you and I ultimately receive may not resemble those of our parents. According to the board of trustees for Medicare and Social Security, the Social Security trust fund's reserves will likely be depleted by 2041. Even Medicare is in trouble, with its trust fund expected to become insolvent by 2019.

Sickening matters
Can it get worse? You betcha. Health-care costs have been skyrocketing. Health-care crises occur to many retired folks, and can often wipe out much or all of their nest eggs. According to the National Coalition on Health Care, "Retiring elderly couples will need $200,000 [if not $300,000, per many experts] in savings just to pay for the most basic medical coverage."

Just think about that $300,000 number. To have that much available (just for health care) by age 70, you'll likely need to have a hefty sum invested already. Start with $45,000 at age 50, and if it grows at the stock market's historical (but not guaranteed) average annual rate of 10%, it will become about $300,000 by age 70. Look at it another way. Let's imagine (admittedly unrealistically) that you'll pay that $300,000 in 30 $10,000 installments, from age 65 to 95. If your nest egg is $1 million at retirement and you withdraw 5% per year, you'll be taking out $50,000, and losing a full 20% of it to health care each year.

Rising health-care costs are even making life difficult for pre-retirees. A survey of Iowa consumers found that fully 86% of respondents had cut back on their savings to pay for health insurance and health care. (Some 44% had even cut back on food and heating.) It's a catch-22: You need to save more now for retirement and its associated health expenses, but it can be harder to do so, given current health expenses.

Even more bad news
Because of the above and other factors, many modern would-be retirees are simply not retiring at all, or are at least retaining part-time jobs. Their golden-year travels are taking them to local casinos instead of Venice and Aruba. Their senior buffet dinners are featuring more macaroni and cheese than caviar and quail.

The bottom line is that many Americans can kiss their imagined retirement goodbye -- and you may be among them (for now).

The good news
Fortunately, your future doesn't have to be so bleak. There are plenty of things you can do right now to improve your retirement considerably. For example:

  • Work just two or three more years longer than you planned to. This article I wrote a while back shows you how you can save hundreds of thousands of extra dollars just by delaying retirement for a few years. Assuming Social Security is still around in a similar form, you can end up with much bigger payments by delaying them, too -- though that's not always the best thing to do. These can help you better afford health care in later years.
  • Beef up your savings and investments for retirement. If you're age 50 or older, you can make extra "catch-up" contributions to your IRA, for one thing -- of $1,000 per year. Extra contributions are permitted for 401(k)s and 403(b)s, too.
  • Invest as effectively as you can, perhaps via some solid mutual funds. ("Safer" options such as money market funds won't grow too rapidly over the long haul, leaving you less safe in retirement.) The Vanguard Capital Opportunity (VHCOX) fund, for example, has returned almost 17% annually, on average, during the past decade. It was recently invested in the likes of Research In Motion (NASDAQ:RIMM), NVIDIA (NASDAQ:NVDA), FedEx (NYSE:FDX), and Corning (NYSE:GLW). It's closed at the moment, but it may well reopen one day, which is why I'm watching it. In the meantime, here's a fund I invested in recently: The T. Rowe Price Media & Telecom (PRMTX) fund, which has averaged almost 18% during the past decade, and has included Amazon.com (NASDAQ:AMZN), AT&T (NYSE:T), and XM Satellite Radio (NASDAQ:XMSR) among its top holdings.          
  • Research shows that one of the biggest predictors of retirement success is the presence of a plan. If you (like most Americans) don't have one, today's your lucky day. Beginning Oct. 8, the Rule Your Retirement team will be taking subscribers through an eight-lesson "How to Plan the Perfect Retirement" online seminar. Reserve your seat for free by signing up for the Rule Your Retirement service. Get more details by clicking here.

So buck up. If you're willing to take a little action, you can make your golden years much more healthy.

Longtime contributor Selena Maranjian owns shares of no company mentioned in this report. Amazon.com, FedEx, and NVIDIA are Motley Fool Stock Advisor recommendations. The Motley Fool is Fools writing for Fools.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.