We all have different goals as we plan for retirement. Many would say having enough money to live comfortably, travel, and enjoy life to its fullest is their main focus. Some would say that being able to move to a "retirement paradise" like a condo on the beach is what they're aiming for.

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However, research has shown that one factor contributes more to happiness (or misery) in retirement than financial security or warm weather: your health. Without good health, you can't enjoy your retirement as much as you'd like, and health problems can easily become a serious drain on even a large retirement nest egg.

What retirees are saying
According to a recent survey by Merrill Lynch, 81% of retirees say that having good health is the most important part of a happy retirement. It's considered even more important than being financially secure or being close with family and friends.

Your physical health can make or break your retirement and can even force you to retire before you're ready. Early retirement is normally considered a sign of financial success, but health problems are the No. 1 reason for retiring early, according to 37% of those who retired before they had planned. Losing one's job later in life came in second at 27% of early retirees, and having sufficient financial resources came in third at just 24%.

Plan to make your health a top priority after you retire
Baby boomers, who make up a majority of current retirees, are already taking a much more proactive role in their health than previous generations. Because of this, nearly 80% of this group believes they will be healthy and active at the age of 75.

For instance, 79% of Baby Boomers actively research health information on their own, as compared with just 18% of the previous generation. A lot of this can be attributed to how easily information can be found nowadays, but there are other indicators of their active role as well. For example, more than twice as many question their doctor's orders, and nearly half view their doctors as "partners" in their healthcare, rather than irrefutable experts whose word should never be questioned.

Invest in your health now
By far the best investment you can make right now is to do everything in your power to give yourself the best chances of a long, healthy retirement.

The same Merrill Lynch survey referred to above found that healthcare expenses are the No. 1 financial worry among retirees. Healthcare costs can be unpredictable, and they can easily eat into your retirement savings. Unexpected healthcare costs are the No. 1 cause of early retirement in America.

The best thing to do is to invest in your health before you retire by developing healthy habits and taking advantage of your healthcare options. See your doctor regularly, as catching a problem (like high cholesterol) early can make all the difference in the world. Sure, medical care can be expensive, but look at it as an investment rather than a burden.

Also, learn about Medicare in advance, including the potential out-of-pocket costs for you. One scary statistic is that only 19% of current Medicare recipients feel like they have a strong understanding of what costs are covered. Understanding Medicare takes some homework on your part. The Centers for Medicare and Medicaid has a good reference to get you started on this.

After all, what's the point of saving and investing for your retirement if you won't enjoy the fruits of your labor for decades to come?

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